You Won’t Believe the Most Common Question after Back Surgery

By Admin

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As a healthcare professional in an orthopedic spine clinic, I field questions all day long from patients about their recovery.

The most common question after back injury or surgery is: “Doc, when can I have sex?”

Our LESS Institute Founder Dr. Kingsley R. Chin advises, “Remember -all our bodies are different, and your medical history, as well as the complexity of the injury or procedure ultimately determine how much time your body needs to heal.”

So although we can’t give an exact answer, there is a guideline that can help you answer that all-important question -just in time for Valentine’s Day.

Consult Your Surgeon

Before you attempt to engage in sexual activity, consult your surgeon to make sure your back is well enough.   You want to make sure that you don’t aggravate your pain or worsen your condition.

Learn

Learn more about your back condition.  Why is this happening? What can or can’t you do for now?  What precautions do you need to take?

Speak

Sit down and speak with your partner about what is happening. Tell them how you feel.  Communication is key as back pain can affect intimacy in the bedroom, as well as relationships in general.

Plan

Yes -that’s right: Plan your positions together.  Research how you can safely position your body to support your back and reduce your pain.  Also speak with your physical therapist for proper body mechanics or positions that will be safe during intercourse.

Explore

Be creative; be imaginative.  Surrender and approach new ideas together.  Try a little more sensuality versus sexuality by pleasuring your partner’s senses with some essential oils or music.

If you are experiencing back pain, don’t hesitate to contact us at the LESS Institute. We understand how challenging living with back pain can be and we’re here to help you.

About the LESS Institute

The LESS Institute is a private academic center of excellence revolving around a new philosophy of Less Exposure Surgery (LES), utilizing the least invasive techniques and technologies to achieve the best and most efficient outcomes so patients can return immediately to an active lifestyle. The LESS Institute prides itself in being the world leader in disc replacement surgery, where patents can get treated with the exclusive AxioMed Freedom cervical and lumbar disc replacements in Kingston, Jamaica. It also has locations in Florida and New Jersey.


Sentinel Sign in Standalone Anterior Cervical Fusion: Outcomes and Fusion Rate

By Dr. Kingsley Chin

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Scientific Paper

Kingsley R. Chin, Fabio J.R. Pencle, Luai M. Mustafa, Moawiah M. Mustafa, Amala Benny, Jason A. Seale

Interested medical professionals can read through the full paper, as published in the Journal of Orthopaedics, here.

Background

The authors aim to demonstrate the feasibility, outcomes and fusion rate of a standalone PEEK cage in the outpatient setting.

Methods

48 consecutive patients undergoing standalone ACDF (S-ACDF) (Group 1) were compared to control group of 49 patients who had ACDF with ACP (Group 2).

Results

Analysis of follow-up at the one year period postoperative outcomes between groups 1 and 2 demonstrated no intergroup statistical significant difference in VAS neck, arm and NDI scores p = 0.414, 0.06 and p = 0.328 respectively.

Conclusion

We conclude that S-ACDF can be safely done in an ambulatory surgery center with satisfactory clinical and patient-reported outcomes.

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Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

About Author Dr. Kingsley R. Chin

Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin is a board certified Harvard-trained orthopedic spine surgeon and professor with copious business and information technology exposure. He sees a niche opportunity where medicine, business and info. tech meet – and is uniquely educated at the intersection of these three professions. He has experience as Professor of Clinical Biomedical Sciences & Admissions Committee Member at the Charles E. Schmidt College of Medicine at Florida Atlantic University, Professor of Clinical Orthopedic Surgery at the Herbert Wertheim College of Medicine at Florida International University, Assistant Professor of Orthopaedics at the University of Pennsylvania Medical School, VisitingSpine Surgeon & Professor at the University of the West Indies, Mona, and Adjunct Professor of Clinical Biomedical Studies at the University of Technology, Jamaica.

Learn more about Dr. Chin here and connect via LinkedIn.

About Less Exposure Surgery

Less Exposure Surgery (LES) is based on a new philosophy of performing surgery, leading the charge to prove through bench and clinical outcomes research that LES treatment options are the best solutions – to lowering the cost of healthcare, improving outcomes and increasing patient satisfaction. Learn more at LESSociety.org.

The LES Society philosophy: “Tailor treatment to the individual aiding in the quickest recovery and return to a pain-free lifestyle, using LES® techniques that lessen exposure, preserve unoffending anatomy and utilize new technologies which are safe, easy to adopt and reproducible. These LES®techniques lessen blood loss, surgical time and exposure to radiation and can be safely performed in an outpatient center. Less is more.” – Kingsley R. Chin, MD

About The LESS Institute

The LESS Institute is the world leader center of excellence in Less Exposure Surgery. Our safe, effective outpatient treatments help patients recover quickly, avoid expensive hospital stays and return home to their family the same day. Watch our patient stories, follow us on Facebook and visit TheLESSInstitute.com to learn more.

Scientific Paper Author & Citation Details

Authors

Kingsley R. Chinabcd, Fabio J.R. Penclee, Luai M. Mustafab, Moawiah M. Mustafab, Amala Bennyae, Jason A. Sealeae

Author information

a. Less Exposure Surgery Specialists Institute (LESS Institute), United States
a. Less Exposure Surgery Specialists Institute (LESS Institute) USA
b. Herbert Wertheim College of Medicine at Florida International University, USA
c. Charles E. Schmidt College of Medicine at Florida Atlantic University, USA
d. University of Technology, Jamaica
e. Less Exposure Surgery (LES) Society, USA


The LESS Institute Fosters Adolescent Scoliosis Care With the Best in LES

By Abagail Sullivan

Written by Fabio Pencle & Garianne Bowen

Compiled & edited by Abagail Sullivan

Adolescent idiopathic scoliosis (AIS) is the most common form of pediatric scoliosis in individuals between the ages of 10 and 18,1 found in as many as 4 in 100 adolescents.2 By definition, idiopathic scoliosis implies the cause is unknown or not related to a specific syndromic, congenital or neuromuscular condition. Treatment options include conservative management, bracing or operative intervention.

Marketing Intern Garianne Bowen is no stranger to a life with adolescent scoliosis, although she may not have known it at first.

“Looking back, though I had the signs of scoliosis growing up, my family wasn’t aware of the potential for this diagnosis. We all thought nothing could be done of it – and though I tried to accept it, I somehow could not,” she said. Bowen spent years settling for a life that held so much more potential, in the physical and emotional space. In a world where lives are hyper visual with social media exposure, “I always felt uncomfortable in my own body. It sometimes felt like I didn’t know how to walk correctly, and that eyes were always on me. My breasts were two different sizes, my stride wasn’t straight, clothes fit awkwardly and I experienced occasional annoying back pain. My shoulder was damaged by birth and my parents attributed that to me being ‘different,'” said Bowen.

Eventually Bowen’s parents discovered an article on scoliosis – and as they read, realized she fit the mold so entirely. Because of this, they scheduled an X-ray to be read by an orthopedic surgeon, witnessing first hand their daughter’s 40 degree spinal curvature.

A proper adolescent scoliosis evaluation includes X-ray imaging from various angles.  Generally speaking, those with curves of 10 to 25 degrees are monitored for surveillance with serial X-rays. This is usually at three, six or 12 month intervals. Those with curves greater than 25 degrees but less than 40 to 45 degrees are candidates for bracing. And those with curves of over 40 to 45 degrees who are skeletally immature are considered operative candidates.3

Bowen’s 40 degree spinal curvature seen through X-ray

Bowen’s 40 degree spinal curvature seen through X-ray

During her preliminary orthopedic visit, her doctor at the time being highly encouraged Bowen to undergo a spinal fusion from the neck down, a more major procedure for an adolescent scoliosis case that would limit Bowen’s flexibility and motion. But Bowen was not so on board. She became determined not to undergo surgery, adapting to a life of covering her curvature and accepting pain as the norm.

Three years post scoliosis discovery, Bowen’s mother met Orthopedic Surgeon Dr. Kingsley R. Chin at a conference. Impressed by his profile as a successful Jamaican-born, Harvard-trained spinal surgeon, she brought her daughter to him straightaway to determine a second opinion regarding treatment options. Dr. Chin assured Bowen he would not be completing a full spinal fusion, introducing a Less Exposure Surgery procedure in its place – and clarifying her every concern regarding maintaining motion post-procedure.

Dr. Chin pioneered this LES procedure, a short segment scoliosis surgery with a focus on the apical curve, gearing treatment to the levels above and below – limiting fusion levels.

“As he reassured me, my perceptions of the procedure were altered for the positive,” she said, and after further personal research and consideration, she ultimately trusted Dr. Chin to perform the surgery. “I am so grateful to have gotten to that place,” attests Bowen.

We know it’s vital to prioritize our health, but we must also expose ourselves to our options that lie ahead. Explore your varying avenues of recovery and choose the most appropriate healing method for you.

I can personally vouch for Dr. Chin as a top orthopedic surgeon, as I begin enjoying my young years to my utmost potential – confident and free of pain.
— Garianne Bowen

And just like that, from curvature to confidence, Bowen leads a life of health, happiness and pain-free motion.

The Less Exposure Surgery Advantage

In advancing Less Exposure Surgery, The LESS Institute aims to reduce operative time, minimize blood loss and decrease instrumentation, while improving overall outcomes. For more on adolescent scoliosis cases with The LESS Institute, see the Jamaica Gleaner article and our post titled 15-Year-Old Jamaican Girl Appreciates Life Changing Scoliosis Surgery in Jamaica by Dr. Kingsley R. Chin.

About Dr. Kingsley R. Chin

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Dr. Kingsley R. Chin is a board certified Harvard-trained orthopedic spine surgeon and professor with copious business and information technology exposure. He sees a niche opportunity where medicine, business and info. tech meet – and is uniquely educated at the intersection of these three professions. He has experience as Professor of Clinical Biomedical Sciences & Admissions Committee Member at the Charles E. Schmidt College of Medicine at Florida Atlantic University, Professor of Clinical Orthopedic Surgery at the Herbert Wertheim College of Medicine at Florida International University, Assistant Professor of Orthopaedics at the University of Pennsylvania Medical School, Visiting Spine Surgeon & Professor at the University of the West Indies, Mona, and Adjunct Professor of Clinical Biomedical Studies at the University of Technology, Jamaica.

  1. , 3. https://www.ncbi.nlm.nih.gov/pubmed/29763083

  2. https://www.srs.org/patients-and-families/conditions-and-treatments/parents/scoliosis/adolescent-idiopathic-scoliosis 


Option for Transverse Midline Incision and Other Factors That Determine Patient’s Decision to Have Cervical Spine Surgery

By Dr. Kingsley Chin

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“I had my [cervical fusion and lumbar decompression] surgery ten days ago and I feel great, I’m wearing my heels and I’m ready to go!”

Introductory content by Fabio Pencle 

“[Dr. Chin] is a true professional… the whole team, the whole staff was great here at the LESS Institute.”

“[Dr. Chin] is a true professional… the whole team, the whole staff was great here at the LESS Institute.”

A newly published study has demonstrated that patients prefer a midline incision for cervical spine surgery.

The anterior approach to cervical spine surgery has become the standard for the treatment for degenerative disc, traumatic herniated disc and fracture dislocation. Cloward, Smith and Robinson have

devised operative techniques with modifications by several surgeons since 1958. There are varying types of skin incisions for cervical spine surgery; the incision is either on the right or left side of the trachea based on the surgical approach to the recurrent laryngeal nerve. Other factors determining the type of incision include a few pathological levels affected, if corpectomy is required and whetheraffected segments are contiguous.

Transverse midline incisions have been used by other surgical specialties such as ENT, vascular and general surgeons. This incision provides a more cosmetically acceptable result and allows for access to structures during surgery; however, few studies discuss the relevance of cosmesis. There are several named guidelines for determining surgical incision, most notably, Langer’s lines. A transverse midline incision would, however, follow the guideline by Kraissl, where the incision is made in a skin crease. The quality of surgery is judged immediately by the amount of relief of symptoms and the cosmetic.

Considering the patient-driven procedures offered to treat the same pathology, as well as recent trends in the increase in ambulatory surgery center (ASC) use, the authors felt it prudent to devise a questionnaire with the primary goal of determining the preferences of the patients. The secondary goal was to determine factors which lead to the decision to have anterior cervical spine surgery.

Scientific Paper

Fabio J.R. Pencle, Jason A. Seale, Amala Benny, Sephania Salomon, Ashley Simela, Kingsley R. Chin

To read the full paper & citations as published in the Journal of Orthopaedics, visit here.

Background

Authors aim to determine patients’ preference for surgical incision and factors affecting the decision for surgery to the anterior neck.

Methods

A questionnaire was presented prior to evaluation and if preceded to surgery followup given.

Results

243 patients completed questionnaire, with 60% female population and younger than 50 years. 151 patients preferred a transverse midline incision with a statistically significant increase in outcomes and cosmesis importance and a decrease in the importance of board certification.

Conclusion

Findings of questionnaire demonstrate that patients’ prefer a transverse midline anterior neck incision, with surgical outcomes being the overall factor affecting decision making.

About Author Dr. Kingsley R. Chin

Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin is a board certified Harvard-trained orthopedic spine surgeon and professor with copious business and information technology exposure. He sees a niche opportunity where medicine, business and info. tech meet – and is uniquely educated at the intersection of these three professions. He has experience as Professor of Clinical Biomedical Sciences & Admissions Committee Member at the Charles E. Schmidt College of Medicine at Florida Atlantic University, Professor of Clinical Orthopedic Surgery at the Herbert Wertheim College of Medicine at Florida International University, Assistant Professor of Orthopaedics at the University of Pennsylvania Medical School, VisitingSpine Surgeon & Professor at the University of the West Indies, Mona, and Adjunct Professor of Clinical Biomedical Studies at the University of Technology, Jamaica.

Learn more about Dr. Chin here and connect via LinkedIn.

About Less Exposure Surgery

Less Exposure Surgery (LES) is based on a new philosophy of performing surgery, leading the charge to prove through bench and clinical outcomes research that LES treatment options are the best solutions – to lowering the cost of healthcare, improving outcomes and increasing patient satisfaction. Learn more at LESSociety.org.

The LES Society philosophy: “Tailor treatment to the individual aiding in the quickest recovery and return to a pain-free lifestyle, using LES® techniques that lessen exposure, preserve unoffending anatomy and utilize new technologies which are safe, easy to adopt and reproducible. These LES®techniques lessen blood loss, surgical time and exposure to radiation and can be safely performed in an outpatient center. Less is more.” – Kingsley R. Chin, MD

About The LESS Institute

The LESS Institute is the world leader center of excellence in Less Exposure Surgery. Our safe, effective outpatient treatments help patients recover quickly, avoid expensive hospital stays and return home to their family the same day. Watch our patient stories, follow us on Facebook and visit TheLESSInstitute.com to learn more.

Scientific Paper Author & Citation Details

Authors

Fabio J.R. Penclead, Jason A. Sealead, Amala Bennyd, Sephania Salomond, Ashley Simelade, Kingsley R. Chinabcf

Author information

a. Less Exposure Surgery Specialists Institute (LESS Institute), United States
b. Herbert Wertheim College of Medicine, Florida International University, United States
c. Charles E. Schmidt College of Medicine, Florida Atlantic University, United States
d. Less Exposure Surgery (LES) Society, United States
e. Bronx Lebanon Hospital Center, United States
f. University of Technology, Jamaica


Here’s How to Choose the Right Spine Specialist for You

By Abagail Sullivan

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Content by Ana Williams

Navigating the healthcare landscape isn’t easy, but it feels like even more of a feat when you’re bogged down with chronic pain amidst your search. Here, we guide you with six helpful steps in choosing the best spine specialist for you.

Make a Decision for Action

The first step to choosing your spine specialist is determining you want to take action. Begin your search straight away once you’ve made the decision. The best spine specialists are prepped to help their patients as soon as they’ve determined the needed treatment, making moves as directly as possible after a consultation. When you feel it’s time to take action, it is!

Commence the Surgeon Search

The spine is a complex collection of bones, nerves and tissue. Make sure your spine specialist has the experience and training to properly handle your condition. Providers devoted primarily to spinal orthopedics will have more experience treating your discomfort than general doctors will. The LESS Institute specializes in spine care with Professor Dr. Kingsley R. Chin, our founder, providing first class care of his own. Dr. Chin is a Harvard trained, board certified and repeatedly honored top surgeon and innovator in less invasive outpatient surgery.

Remember to Reference

Studies suggest that almost 80% of Americans will experience lower back pain, which means you’re bound to know a family member, friend or coworker who’s been treated by or heavily researched a spine specialist. There’s nothing like a personal referral to start. If that particular specialist is booked up or not accepting new patients, be sure to ask their office for an additional reference in the right direction.

Take the Time for Testimonials

Patients can provide the most personal insight into the type of care you may receive from the doctor and facility. Ask your potential surgeon to see their testimonials, or check out the practice’s website and social media pages for further info. At the LESS Institute, we’re huge patient advocates and hope they, too, feel the same in return. For our dedicated patients’ testimonials, head here.

Meet the Doc

Sure, you can learn a lot from research and online reviews, but you’ll get a much stronger feeling about your doctor by sitting down with them in person. An appointment will give you the opportunity to talk through your situation and discuss treatment goals. To request an appointment with our LESS Institute team, call us any time at 855-411-LESS.

Prep Your Qs

Undoubtedly, there will be aspects of your condition or recommendations for relief that you may not fully understand. Make sure to bring your past records and questions at the time of your visit so your surgeon can use that face to face time to explain next steps. The LESS Institute S.E.R.V.E. team, our concierge gurus, personally sits down with you (and even your family!) to educate on the recommended procedure to guide you on your road to relief. The concierge hotline is open to those patients getting a procedure and who may have questions after hours.

We’ve witnessed the hardships of living with chronic pain through our patients, and we hope these tips help you navigate the often overwhelming world of healthcare – to find the best spine specialist fit for you.


Our LESS Institute Team Joins the Pack (Again!) With Food for the Poor

By Abagail Sullivan

Our team joined the pack and Food for the Poor for another successful day of providing sustenance to hungry families abroad.

Guatemala has one of the highest rates of chronic child malnutrition in the world, with less than half of rural Guatemalans with access to running water, only a quarter with availability of electricity and only about one in 10 with means of modern sanitation facilities. This severe food insecurity and lack of accessible, affordable medical care has led to high infant, child and maternal mortality rates.

So our team joined the pack to help gather a whopping 150,120 meals for families in Latin America and the Caribbean, alongside hundreds of generous volunteers at the Third Annual Join the Pack Event – featuring specially formulated MannaPack meals that provide direly needed sustenance to families abroad unable to afford for their own.

“Food for the Poor gave me a sense of purpose and desire to do more for the less fortunate. As I stood inside the gymnasium surrounded by all the other volunteers I noticed how happy everyone was and eager to work together toward a greater cause. We were all determined to make as many meals as possible in the allotted time, even if it meant our backs or arms became sore from standing for hours in an assembly line – because the thought of malnourished children made it more than worth it. Volunteers that entered as strangers were high-fiving by the final count and have become lasting friends. I can’t wait to join again for our third year in a row,” attests Marketing Manager Esther Rodriguez.

This day of giving is filled with such camaraderie, positivity and light.

And LESS Institute Scheduling Coordinator Ana Williams agrees. “After year one of ‘joining the pack,’ we knew we’d return. This day of giving is filled with such camaraderie, positivity and light, we encourage all those who can to get involved in making even a small difference in the worlds of so many families abroad.”

We send our sincerest thank yous and gratitude to Food for the Poor, our LESS Institute team members, our fellow Manna-packers, donation givers and everyone who spread the word of this noteworthy cause!

Discover more about Food for the Poor and the motivation behind this wonderful event. And visit us on Facebook to check out our team photos and beyond.

Photos by Food For The Poor


Utility of Mobile Apps for Video Conferencing to Follow Patients at Home After Outpatient Surgery

By Dr. Kingsley Chin

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Author Information

Fabio J.R. Pencle1 MB BS, Amala Benny1, Kathleen A. Quijada BS3, Jason A. Seale2 MB BS, Kingsley R. Chin2, 3 MD

  1. Less Exposure Surgery (LES) Society.

  2. Less Exposure Surgery Specialists Institute (LESS Institute).

  3. Herbert Wertheim College of Medicine at Florida International University and Charles E. Schmidt College of Medicine at Florida Atlantic University

Study Design

Prospective questionnaire

Background Data

The role of technology in medicine has been limited to patient use in decision making for finding and assessing physicians. Teleconference is real time and live interactive program in which one set of participants are at one or more locations and the other set of participants are at another location. The teleconference allows for interaction, including audio and/or video, and possibly other modalities, between at least two sites. A study by Augestad et al has demonstrated from the literature the use of video conferencing for surgeons and its benefits especially in rural areas. Newer technology has allowed mobile video conferencing with encryption specific to the application or mobile phone. Outpatient surgery has a great opportunity to demonstrate the role of utilizing video conference (VC) in the follow up of patients postoperatively. The authors aim to assess patient’s perception to the use of mobile app for video conference (VC) with surgeon and/or staff.

Methods

Patients who presented to an orthopedic institute were presented with a questionnaire. To determine patient attitudes regarding surgery and the use of mobile VC app, we asked the surveyed participants using a 5 point Likert scale. Consenting patients completed a questionnaire of 10 questions prior to being assessed by surgeon in order to minimize any bias resulting from evaluation and treatment. Patients who proceeded to have surgery completed the questionnaire to assess difference in opinion postoperatively.

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Results

120 patients completed the questionnaire preoperatively with 58% female population, 71% age younger than 65 years and 67% having a GED/higher education. A total of 36 patients had surgery with 54% female population and 60% age younger than 65 years. All patients had a mobile app for VC with 55% using WhatsApp, 40% using Facetime, 5% Skype and/or other. In person at office with a trained educator was the preferred mode and method for learning about surgical procedures. Eighty-three percent of patients thought that having mobile video app access suggested that their surgeon was more caring preop compared to 89% post op. Overall; four patients contacted the surgeon directly preoperatively. Post-surgery 5/36 patients (14%) utilized video conference to the surgeon directly, 24 patients contacted the concierge team with video conference.

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Conclusion

With advances in technology, the use of mobile video conferencing adds a new forum for communication with patients. In the outpatient surgical setting this forum would improve patient-physician relations.

About Author Dr. Kingsley R. Chin

Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin is a board-certified Harvard-trained Orthopedic Spine Surgeon and Professor with copious business and information technology exposure. He sees a niche opportunity where medicine, business and info. tech meet – and is uniquely educated at the intersection of these three professions. He has experience as Professor of Clinical Biomedical Sciences & Admissions Committee Member at the Charles E. Schmidt College of Medicine at Florida Atlantic University, Professor of Clinical Orthopedic Surgery at the Herbert Wertheim College of Medicine at Florida International University, Assistant Professor of Orthopaedics at the University of Pennsylvania Medical School, Visiting Spine Surgeon & Professor at the University of the West Indies, Mona, and Adjunct Professor of Clinical Biomedical Sciences at the University of Technology, Jamaica.

Learn more about Dr. Chin here and connect via LinkedIn.

About Less Exposure Surgery

Less Exposure Surgery (LES) is based on a new philosophy of performing surgery, leading the charge to prove through bench and clinical outcomes research that LES treatment options are the best solutions – to lowering the cost of healthcare, improving outcomes and increasing patient satisfaction. Learn more at LESSociety.org.

The LES Society philosophy: “Tailor treatment to the individual aiding in the quickest recovery and return to a pain-free lifestyle, using LES® techniques that lessen exposure, preserve unoffending anatomy and utilize new technologies which are safe, easy to adopt and reproducible. These LES®techniques lessen blood loss, surgical time and exposure to radiation and can be safely performed in an outpatient center. Less is more.” – Kingsley R. Chin, MD

About The LESS Institute

The LESS Institute is the world leader center of excellence in Less Exposure Surgery. Our safe, effective outpatient treatments help patients recover quickly, avoid expensive hospital stays and return home to their family the same day. Watch our patient stories, follow us on Facebook and visit TheLESSInstitute.com to learn more.

About SpineFrontier

The above study utilized LES Technology from SpineFrontier – leading provider of LES Technologies and instruments – offering surgeons and patients superior technology and services.

Correspondence

Kingsley R. Chin, MD

Professor of Clinical Orthopedics

Herbert Wertheim College of Medicine at Florida International University

Attending Spine Surgeon

Less Exposure Surgery Specialists Institute (LESS Institute).

3816 Hollywood Blvd, #102 Hollywood FL 33021.

Tel: 954-640-6010 Fax: 855-411-4647 Email: kingsleychin@thelessinstitute.com

Conflicts of interest and sources of funding: We did not seek or receive any funding from the National Institutes of Health (NIH), Wellcome Trust, Howard Hughes Medical Institute (HHMI), or others for this work. KRC is a shareholder in and receives other benefits from SpineFrontier Inc., none of the other authors (FJRP, AB, KAQ and JAS) have any potential conflicts of interest to declare for this work.

Acknowledgements

The authors would like to thank Saily Lopez and the Surgical Education Responsibilities Value and Empathy (S.E.R.V.E) ™ team for their assistance with this project.


Radiographic and Histologic Comparison of NanoFUSE® DBM and a Bioactive Glass in a Rabbit Spinal Fusion Model

By Admin

NanoFuse is a biologic tech company acquired by Dr. Kingsley R. Chin, through his private equity firm KICVentures.

Scientific Paper

James F. Kirk , Gregg Ritter, Michael J. Larson, Robert C. Waters, Isaac Finger, John Waters, John H. Abernethy, Dhyana Sankar, James D. Talton and Ronald R. Cobb

Abstract

Autologous bone has long been the gold standard for bone void fillers. However, the limited supply and morbidity associated with using autologous graft material has led to the development of many different bone graft substitutes. The use of bone graft extenders has become an essential component in a number of orthopedic applications including spinal fusion. This study compares the ability of NanoFUSE® DBM and a bioactive glass product (NovaBone Putty) to induce spinal fusion in a rabbit model. NanoFUSE® DBM is a combination of allogeneic human bone and bioactive glass. NanoFUSE® DBM alone, and in combination with autograft and NovaBone Putty, were implanted in the posterior lateral intertransverse process region of the rabbit spine. The spines were evaluated for fusion at 12 and 24 weeks for fusion of the L4-L5 transverse processes using a total of 64 skeletally mature rabbits. Samples were evaluated by manual palpation, radiographically, histologically, and by mechanical testing. Radiographical, histological, and palpation measurements demonstrated the ability of NanoFUSE® DBM to induce new bone formation and bridging fusion. The material in combination with autograft performed as well as autograft alone. In addition, the combination of allogeneic human bone and bioactive glass found in NanoFUSE® DBM was observed to be superior to the bioactive glass product NovaBone Putty in this rabbit model of spinal fusion. This in vivo study demonstrates the DBM and bioactive glass combination, NanoFUSE® DBM, could be an effective bone graft extender in posterolateral spinal fusions.

Introduction

The use of autograft material remains the gold standard for use in orthopedic procedures due to the fact that there is little chance of immune rejection and its innate osteoconductive, osteoinductive, and osteogenic potential. Due to the significant levels of pain and morbidity at the donor site, bone graft substitutes are commonly used [1-4]. Bone graft substitutes offer a wide range of materials, structures, and delivery systems to be used in bone grafting procedures. Common sources of bone graft materials include allogeneic bone, synthetic calcium phosphate salts, coralline materials and bioactive glass. These materials should possess one or more of the characteristics typical of autograft material including osteoconductivity, osteoinductivity and osteogenicity. Human derived demineralized bone matrix (DBM) has become a very common bone graft substitute which has shown the ability to aid in new bone formation in many different clinical settings including long bone defects, craniofacial reconstruction, and spinal fusion [5-9]. DBM in combination with local bone has been shown to perform as well as autograft, potentially eliminating the need for autogenous bone harvesting [8]. Studies have shown that allogeneic DBM possesses inherent osteoconductive and osteoinductive properties, as well as containing numerous bone morphogenic proteins (BMPs) that initiate the cascade of new bone formation [10-13]. There are several commercially available DBM products for use in spinal surgery. Many of these have been tested using rabbit spinal fusion model [14, 15] revealing differences in fusion rates. The different osteoconductive capabilities of these products have been explained as a consequence of the processing methods, as well as the age and quality of the donor bone [11, 16- 24]. NanoFUSE® DBM was created to take advantage of the osteoconductive and proangiogenic properties of bioactive glass as well as the osteoinductive properties of human-derived DBM. The bioactive glass portion of NanoFUSE® DBM is composed of 45S5 composition disclosed by Hench (also known as Bioglass® ). Previous studies have shown that the NanoFUSE® DBM is biocompatible and has both osteoconductive and osteoinductive properties [25]. During the last couple of decades, the development of new implant technologies have shifted from attempts to create a passive interface between the implant and the native tissue to the design of bioactive materials. Within this category are a wide range of synthetic calciumphosphate ceramics, bioactive glass, and bioactive glass-ceramics [26, 27]. Advantages of 4 synthetic materials include tunable resorption rates, increased mechanical strength compared with DBM products, controlled porosity, and ideal processing and molding parameters [28, 29]. Bioactive glass is the first man-made material to form a direct chemical bond with bone. When in contact with surface-reactive bioactive glass, osteoblasts undergo rapid proliferation forming new bone in roughly the same time period as the normal healing process. Bioactive glass has been proven effective in generating new bone in several different pre-clinical animal studies [30- 33], as well as in approved products on the market. In addition, only a minimal amount of bioactive glass is required to induce graft bioactivity. One such bioactive glass based material is the currently marketed NovaBone Putty. Numerous investigations examining implant resorption and bone formation of various bone graft substitutes and extenders have been performed [7, 8, 14, 34-36]. In the present study, NanoFUSE® DBM was evaluated and compared to a bioactive glass based material, NovaBone Putty to induce bone formation and bridging fusion in a rabbit posterolateral spinal fusion model. This animal model has been widely used for evaluating spinal surgery technique and spinal fusion implant materials. The surgery involves fusion of the L4-L5 motion segments without plating or stabilization. Test materials were implanted in the posterior lateral L4-L5 intertransverse process region of the spine and were analyzed for up to 24 weeks.

Materials & Methods

Implant Materials

The NanoFUSE® DBM used for these studies was prepared from DBM derived from the long bones of rabbits. The demineralization process was similar to that described by Urist [12]. The final particle size was a distribution spanning 125 to 710m. Bioactive glass, of the 45S5 composition, was purchased from Mo-Sci Health Care, LLC (Rolla, MO). The composition of the 45S5 (w/w%) was 43 – 47% SiO2; 22.5 – 26.5% CaO; 5 – 7% P2O5; and 22.5 – 26.5% Na2O with a particle size distribution of 90 – 710 µm (≥ 90%). NanoFUSE® DBM was formulated essentially as described [25]. The material was hydrated and warmed immediately prior to implantation. NovaBone Putty was obtained and prepared using aseptic techniques. Autograft was harvested in select animals from the iliac crests and morselized with Rongeur forceps to an approximate diameter of 5 mm or less. The target volume of bone graft material to be placed for each lateral side of the motion segment was 3cc.

Surgical Procedures

New Zealand White rabbits (64) were obtained from Western Oregon Rabbit Company (Philomath, OR), weighing approximately 4 kg each (Table 1 for experimental design). Animals were acclimated to the facility for a minimum of one week and completed a pre-study physical examination prior to research use. Each rabbit was weighed prior to surgery to enable accurate calculation of anesthesia drug dosages and to provide baseline body weight for subsequent general health monitoring. Glycopyrrolate (0.1 mg/kg) was administered intramuscularly (IM) approximately 15 minutes prior to anesthesia induction to protect cardiac function during general anesthesia. Butorphanol (1.0 mg/kg) and acepromazine (1-2 mg) were also administered for sedation and early post operative analgesia. General anesthesia was induced with an IM injection of ketamine (25-30 mg/kg) and xylazine (7-9 mg/kg), followed by endotracheal intubation. Anesthesia was maintained with isoflurane (0-4%, to effect) in oxygen. A 24 gauge intravenous (IV) catheter was introduced into the marginal ear vein and secured to the skin. Yohimbine (Yobine, Lloyd Laboratories, Shenandoah, IA), was administered intravenously (0.2 6 solution was administered intravenously at a rate of 10-20 ml/kg/hr during the surgical procedure. A dorsoventral radiographic image of the lumbar spine was obtained prior to operative site preparation to identify the targeted L4-5 operative site. The fur over the operative site was then removed with an electric clipper to expose a sufficient area of skin for aseptic surgery and autograft harvest, if indicated. The skin was subsequently scrubbed with a povidone iodine surgical scrub followed by 70% isopropyl alcohol rinse. This process was repeated at three times. Sites were then painted with a povidone iodine solution. The animal was transferred into the operating room and draped for aseptic surgery. The spine was approached through a single midline skin incision and two paramedian fascial incisions. The L4-L5 levels were identified during surgery by referencing the preoperative radiographic images and iliac crest palpation. The dorsal surfaces of the transverse processes (TPs) of L4 and L5 were then bilaterally exposed and approximately 2 cm of each TP was decorticated with a motorized burr [37] Hemorrhage was controlled with pressure and the judicious use of cautery. The gutters were flushed with 1-2 cc of saline to facilitate removal of bone dust and clots. Approximately 3.0 cc of each material was placed in the paraspinal gutters, forming a continuous bridge over and between the decorticated TPs of L4 and L5. (see Table 1 for experimental design). After the bone graft materials were implanted and TP bridging was verified by visual inspection, the fascia was closed with sutures in two layers and the skin was approximated with staples. The rabbits were recovered from anesthesia with supplemental heat and were returned to their home cages after they became ambulatory. Supplemental butorphanol (1 mg/kg) was administered for pain approximately 3 hours after extubation while fentanyl blood levels increased. At 3, 9 and 18 weeks after surgery, animals were humanely euthanized by intravenous injection of barbiturate solution. The lumbar spines were explanted during necropsy examination and the operative sites were evaluated for fusion using manual palpation, radiography, histological analyses, and mechanical testing.

Manual Palpation

Manual palpation is the gold standard for evaluating posterolateral lumbar fusion in experimental animals. In the present study, first the spines were explanted, and the L4-L5 segment was tested with manual palpation. Two reviewers independently evaluated the spines for fusion in a blinded fashion. Fusion was deemed successful whenever there was no segmental 7 motion between adjacent vertebrae in lateral bending and flexion and extension planes. When reviewers disagreed in their fusion evaluation, a third reviewer evaluated the explanted spines to make the final determination of fusion.

Mechanical Testing

All mechanical testing was performed by Numira Biosciences (Bothell, WA). Six samples from each group from the 24-week time point was be properly stored and then evaluated for uniaxial tensile testing. After the remaining muscle and facet joints were removed, pilot holes were drilled ventral to dorsal through two adjacent vertebral bodies. Just prior to testing, the intervertebral disc was divided with a scalpel so that only the intratransverse membrane and fusion mass was left to connect the two adjacent vertebrae. Stainless steel pins were inserted through the pre-drilled holes and connected to a steel wire attached to the material testing device. Biomechanical testing was performed using an Instron 5500R running Bluehill version 2.5 software. Using the jog up controller, each sample was brought to a point where no slack was present in the steel wires hooked to the pins. A tension load was applied to the specimen at a rate of 6mm/min until failure. To obtain maximum load, the cursor was placed at the peak of the load extension curve. To obtain stiffness, the steepest part of the load extension curve was identified and the cursor was placed at the lower end of the slope and then at the upper end. Stiffness was determined as the slope of this line. To obtain energy, if the curve continued to rise without a break or pause in the load-extension curve, the cursor was placed at the point where the curve began to rise and then at the point of the maximum load. If there was a break or pause in the load-extension curve, the cursor was placed at the point where the load-extension curve began to rise, then at the point where the load-extension curve began to pause, then at the point where the pause ended, and finally at the point of maximum load. Energy is the area under the curve, which is the sum of two energy values if there is a pause in the curve. Following cursor placement, the software performed the calculations and displayed the results. The software provided Maximum Load, Stiffness, Energy, and Extension (at Maximum Load).

Radiographic Assessment

Posteroanterior radiographs were performed immediately after surgery, and at approximately 4, 8, 12, 18, and 24 weeks post surgery. Radiographic images were evaluated for evidence of new bone growth, implant integration and radiographic fusion, defined as mineralized or trabecular bone bridging between the transverse processes of the L4-L5 lumbar 8 vertebrae. Images that were graded as fused were determined to have a mineralized bone bridge between the L4-L5 vertebrae. Images that were graded as not fused may have demonstrated considerable new bone in the L4-L5 interspaces, thin radiolucent fissures transversing the fusion masses or radiolucent zones near the vertebrae, interrupting what would otherwise have been a continuous bone bridge between the transverse processes. Images demonstrating significant radiodensity from the implants were graded as ‘fusion indeterminate’ and were not included in the fusion scores.

Histopathology

Three animals per group will be utilized for histological evaluations. Processing of the slides was performed by Laudier Histology (New York, NY). Freshly prepared samples of implant material were fixed in 10% formalin, embedded in methyl methacrylate, and then sectioned 5m thick. The sections were stained with toluidine blue to visualize new bone and cartilage formation. Histological scoring was performed based on bilateral assessment as described in Table 2. Pathologic evaluation was performed for the implant sites to determine degree of new bone development in the implant sites as well as to determine spinal fusion (bridging bone)

Results

Surgery

Sixty four (64) animals underwent surgery for this study (see Table 1 for experimental design), but a total of 63 survived the study. One sham treated animal died one week postsurgery and was not replaced. The rabbits recovered well from the general anesthesia and weight gain patterns throughout the study were normal. After several days, surviving rabbits were ambulating normally and demonstrated normal appetites and behavior patterns. These patterns remained normal for the study term.

Manual Palpation

Stiffness of the fused motion segment was assessed by manual palpation. The fusion was graded by two independent blinded observers. If no detectable motion was observed, this was graded as fused. The spines that demonstrated motion between the L4-L5 vertebrae were graded as not fused. As shown in Table 3, the sham control group did not demonstrate any spinal fusion at all time points. NovaBone Putty did not demonstrate any spinal fusion at all time points. The NanoFUSE® DBM group alone demonstrated 11% (1/9) fusion rate at the 24 week time point. The NanoFUSE® DBM plus autograft group demonstrated similar levels of fusion rates (56% – 5/9) when compared to the autograft alone group (67% – 6/9). At the 12 week time point, only the autograft group demonstrated any spinal fusion (2/2) while all other groups demonstrated 0% fusion (0/3).

Mechanical Testing

During preparation of the specimens, the facet joint (dorsal elements) connecting the vertebrae at the fusion level on one specimen from the NanoFUSE® DBM only group was not removed. Data from this one sample reflects the strength of both the fusion mass and the dorsal elements and therefore was removed from the dataset. The patterns of the data were similar for maximum load (Table 4) with autograft and NanoFUSE® DBM plus autograft demonstrating the highest scores. As shown, each of the treatment groups had higher maximum load compared to the sham control group. The maximum load was 159.77±44.58 N for the Sham group, 229.32±94.44 N for the autograft group, 198.69±136.65N for the NovaBone Putty group, 173.00±19.5 N for the NanoFUSE® DBM group and 248.92±74.74 N for the NanoFUSE® DBM+autograft group. However, these differences were not statistically significant. In a similar fashion, autograft and NanoFUSE® 10 DBM plus autograft demonstrated the highest stiffness scores. NanoFUSE® DBM alone had only slightly higher stiffness scores than the sham group, but was higher than the scores observed for NovaBone Putty. It is interesting to note that only the NovaBone Putty had scores that were lower than the sham group with respect to stiffness. The stiffness values were 62.62±16.86 N/mm for the sham group, 90.39±18.39 for the autograft group, 50.24±28.34N/mm for the NovaBone Putty group, 69.04±26.68 N/mm for the NanoFUSE® DBM group and 85.14±9.52 N/mm for the NanoFUSE® DBM plus autograft group. However, these differences were not statistically significant. NovaBone Putty demonstrated the highest extension scores. With respect to the other groups, there was little effect of treatment on extension. The extension values were 6.27±1.38 cm for the sham group, 5.13±2.73 cm for the autograft group, 8.45±3.91cm for the NovaBone Putty group, 5.99±1.69 cm for the NanoFUSE® DBM group and 5.70±1.37 cm for the NanoFUSE® DBM plus autograft group. However, these differences were not statistically significant. NanoFUSE® DBM plus autograft had the highest scores with respect to energy. NanoFUSE® DBM alone and autograft had similar numbers which were higher than the sham controls. NovaBone Putty had energy scores that were lower than the sham controls. The energy values were 299.33±123.32 mJ for the sham group, 339.21±283.28 mJ for the autograft group, 207±139.33 mJ for the NovaBone Putty group, 393.08±138.13 mJ for the NanoFUSE® DBM group alone, and 514.81±252.32 mJ for the NanoFUSE® DBM plus autograft group. However, these differences were not statistically significant. Overall, the load, stiffness, extension, and energy for NanoFUSE® DBM plus autograft were equivalent to the pure autograft, however the NanoFUSE® DBM alone demonstrated lower values for stiffness, extension, and load which were similar to the sham controls. NovaBone Putty demonstrated lower scores than the sham treated animals in stiffness and energy, but had the highest scores of all treatment groups with respect to extension.

Radioactive Analyses

Radiographic images generated for this study were evaluated for evidence of new bone growth, implant integration and radiographic fusion, defined as mineralized or trabecular bone bridging between the transverse processes of the operated segments. Radiographic fusion was judged by continuous trabecular bridge between L4-L5 transverse processes. Each side was scored independently and had to have continuous bridging bone between the transverse processes 11 to be scored as fused (Figures 1 and 2). Images demonstrating significant radiodensity from the implants were graded as “fusion indeterminate” and were not scored as fusion. At 4 weeks, the autograft group demonstrated 79% (19/24) fusion while the NanoFUSE® DBM plus autograft demonstrated a 54% (13/24) fusion rate (Table 5). NanoFUSE® DBM alone and the sham control did not demonstrate any fusion at this time point. All samples from the NovaBone Putty demonstrated significant radiodensity from the implant material and were scored as “fusion indeterminate.” At 8 weeks, the autograft group demonstrated 92% (22/24) fusion rate while the NanoFUSE® DBM plus autograft demonstrated a 75% fusion rate (18/24). Fusion was observed in the NanoFUSE® DBM alone group at eight weeks (4/24, 17%). No fusion was observed for either the sham or NovaBone Putty groups. Ten segments from the NovaBone Putty group demonstrated significant radiodensity and were scored as “fusion indeterminate.” By 12 weeks, the autograft and NanoFUSE® DBM plus autograft groups demonstrated similar fusion rates. Fusion was observed in the NanoFUSE® DBM alone group (7/24, 29%) while no fusion was observed in the sham or NovaBone Putty groups. By 18 and 24 weeks, autograft and NanoFUSE® DBM plus autograft demonstrated similar levels of fusion. The levels of fusion for the NanoFUSE® DBM alone group were similar in both the 18 and 24 week time points (56% and 61%, respectively). No fusion was observed in the sham or NovaBone Putty groups at the 18 and 24 week time points.

Histological Evaluation

Histologic results showed that all test articles were well tolerated in the test animal. There was no significant inflammation or foreign body giant cell response. Histologic data are provided in Table 6 and representative images are found in Figure 3 (12 week time point) and Figure 4 (24 week time point). Implant sites from all animals at the 12 week time point from the sham group , consisted of variable amounts of new bone with bone marrow, fibrosis and adipose tissue. New bone growth that was observed consisted of a minimal to mild amount of new bone and bone marrow. Two of the implant sites contained a minimal amount of cartilage. In addition, a minimal amount of neovascularization and adipose tissue infiltration was observed. A representative slide from this group is found in Figure 4A. The tissue samples from the autograft group consisted of new bone, bone marrow, fibrosis and adipose tissue at the 12 week time point. Three samples from this group demonstrated 51-100% of bridging of the defect with new bone. The new bone in all of the 12 implant sites consisted of minimum to mild amounts of new bone and a minimal to marked amount of bone marrow. The tissue reaction of these samples contained a minimal number of macrophages and multinucleated giant cells. A representative slide from this group is shown in Figure 3B. The autograft samples from the 24 week group demonstrated very little evidence of the implant material. The samples contained 51-100% of bridging of the defect site with new bone with a moderate amount of bone marrow. A minimal amount of neovascularization was observed in the tissue samples from this group. The tissue reaction of the samples contained a minimal number of macrophages and multinucleated giant cells. A representative slide from this group is presented in Figure 4B. At the 12 week time point, NovaBone Putty implant sites contained a significant amount of residual implant material (76-100%). The implanted material consisted of many variably sized closely packed pieces of pale blue anuclear material. The implant material was found within the new bone growth. All of the 12-week implant sites had 1-25% of bridging of the defect with new bone. The new bone consisted mainly of a minimal amount of new bone and bone marrow. The tissue reaction of the samples contained minimal numbers of lymphocytes. The minimal amount of adipose tissue that was observed was a healing response of the muscle tissue adjacent to the implant sites. A representative slide from this group is presented in Figure 3C. The 24 week NovaBone Putty implant sites consisted mainly of the implant material, new bone and bone marrow. All of the implant sites contained moderate levels of residual implant material (51-75%). The implant material consisted of many variably sized closely packed pieces of clear to pale blue anuclear material. The implant material was surrounded and divided by the fibrosis and chronic inflammatory cells. The samples contained 1-25% of bridging bone across the defect and the percentage of the implant site occupied by new bone was 1-25%. The tissue reaction of all of the NovaBone Putty implant sites contained a moderate number of macrophages and a minimal to mild number of multinucleated giant cells. The adipose tissue that was observed was a healing response of the muscle tissue adjacent to the implant sites. A representative slide is presented in Figure 4C. At the 12 week time point, the NanoFUSE® DBM implant sites contained a minimal amount of implanted material (1-25%). The implanted material consisted of small fragments of light blue anuclear material. The implant material was found within the new bone growth. There was 51-99% bridging of the defect with new bone and the percentage of the implant site 13 occupied by new bone was 26-75%. The new bone consisted of a minimal amount of new bone and a moderate amount of bone marrow. The tissue reaction of these sites contained a minimal number of macrophages and multinucleated giant cells and a minimal amount of adipose tissue. A representative slide is presented in Figure 3D. The NanoFUSE® DBM group samples at the 24 week time point contained a minimal amount (1-25%) of the implanted material. The implanted material consisted of small fragments of light blue anuclear material. The implant consisted of a minimal amount of new bone with a minimal to moderate amount of bone marrow and adipose tissue. The implant sites had 1-25% or 100% bridging of the defect with new bone and the percentage of the implant site occupied by new bone was 1-25% or 76-100%. The tissue reaction of all the samples contained a minimal number of macrophages and multinucleated giant cells. A representative slide from this group is presented in Figure 4D. The NanoFUSE® DBM plus autograft group implants at the 12 week time point contained a minimal amount (1-25%) of the implanted material. The implanted material consisted of small fragments of light blue anuclear material. The implant sites consisted of a minimal to mild amount of new bone, a mild amount of bone marrow and adipose tissue. There was 51-100% bridging of the defect with new bone and the percentage of implant sites occupied by new bone was 51-75%. The tissue reaction to these implants contained a minimal to mild amount of adipose tissue, a minimal number of macrophages, and a minimal number of multinucleated cells. A representative slide is shown in Figure 3E. At the 24 week time point, the NanoFUSE® DBM plus autograft group implant sites contained a minimal to mild amount of new bone and a mild to moderate amount of bone marrow. A minimal amount (1-25%) of the implanted material was still visible as variably sized closely packed pieces of pale blue anuclear material. All of the implant sites in this group had 100% bridging of the defect with new bone and the percentage of the implant site occupied by new bone was 51-100%. There was also a minimal amount of neovascularization observed. The tissue reaction of all the implants contained a minimal number of macrophages and multinucleated giant cells. A representative slide is presented in Figure 4E.

Discussion

The need for bone graft materials is an ongoing challenge in orthopedics. Many different biomaterials are becoming available for use in orthopedic reconstruction [38, 39]. The use of commercially available DBM as a supplement to autogenous bone is becoming increasingly common [7, 8, 15, 40]. However, autogenous bone remains the gold standard for use in orthopedic procedures due to its osteoinductive, osteoconductive, and osteogenic potential. Due to postoperative morbidity, and in revision cases where the autogenous iliac crest bone graft is limited, the search continues for effective alternatives. The development of novel bone graft substitutes with novel properties can expand the use of these materials in orthopedic treatments. Bone graft substitutes should possess one or more of the characteristics typical of autograft. These materials should be biocompatible, possess osteoconductive as well as osteoinductive properties, and should degrade in concert with bony replacement. Bioactive glass is the first man-made material to form a direct chemical bond with bone. It is also the first man-made material to exert a positive effect on osteoblastic differentiation and osteoblast proliferation [41]. The composition of the bioactive glass portion of NanoFUSE® DBM is the same as that of Hench’s Bioglass. Years of testing, preclinical, and clinical use have demonstrated the safety and efficacy of this material [42]. Bioactive glass has traditionally been employed for its osteoconductive and osteostimulative properties [41, 43, 44]. Recently, data has been presented demonstrating the proangiogenic potential of bioactive glass in vitro and in vivo [44]. In addition, these studies have shown that the soluble dissolution products of bioactive glass can stimulate the production of proangiogenic factors, thereby providing a potentially promising strategy to enhance neovascularization and resultant bone formation. Wheeler et al demonstrated equivalent rates of bone growth for bioactive glass particles, for autograft, and reported rapid proliferation of bone in contact with the bioactive glass particles [33]. Further studies have shown that new bone occupied an average of 50% of the femoral condyle defect area at three weeks in a group of animals treated with a phase pure porous silicate-substituted calcium phosphate ceramic [45]. Additional studies have suggested that Bioglass particles may have advantages over other bone graft substitute materials [33, 46]. In contrast, an evaluation of 45S5 bioglass for osteoconductive and osteoinductive effects in a calvarial defect demonstrated only 8% new bone formation and various degrees of inflammation [47]. Other authors also 15 described multinuclear giant cells associated with Bioglass particles in a rabbit distal femur model [48]. Previous studies have demonstrated the biocompatibility of the NanoFUSE® DBM material [25]. These studies also demonstrated that NanoFUSE® DBM materials meet the criteria for an ideal bone graft, namely because they possess osteoconductive as well as osteoinductive properties, degrade in concert with bony replacement, and are biocompatible. NanoFUSE® DBM combines the osteoconductive and proangiogenic properties of bioactive glass with the osteoinductive properties of human DBM. While each of these is important, it is the osteoinductive nature of DBM that enables bone generation to occur throughout a defect rather than simply at the edges [6]. The purpose of this study was to evaluate and compare the capacity of NanoFUSE® DBM and NovaBone Putty to induce osteogenesis and bridging fusion in a rabbit spinal fusion model. Test materials were implanted in the posterolateral inter-transverse process region of the spine and analyzed at various different time points. Samples were evaluated radiographically, histologically, by manual palpation, and by mechanical strength testing. Similar models have been used to verify autograft extenders with reproducible results. The manual palpation rate of 67% observed in the autograft control group is consistent with the rate demonstrated in previous studies [37, 49-53]. NanoFUSE® DBM in combination with autograft demonstrated increased fusion rates when compared to sham controls. NanoFUSE® DBM in combination with autograft demonstrated equivalent fusion rates when compared to autograft controls when measured with manual palpation or radiographically. The ability of NanoFUSE® DBM to homogeneously mix with the morselized autograft allowed a continuous mixture of substrate with minimal void within the graft site for new bone to develop and fuse the motion segment. Radiographic analyses also showed similar fusion rates when NanoFUSE® DBM plus autograft and autograft. In addition, implant sites from NanoFUSE® DBM alone group demonstrated >50% fusion rates as determined by radiographic analyses. In contrast, no fusion was observed either by manual palpation or radiographic methods for animals treated with NovaBone Putty. The results of this rabbit spinal fusion study demonstrate the biocompatibility of the NanoFUSE® DBM material. They also demonstrate that the NanoFUSE® DBM material is significantly resorbed (only 1-25% of the implanted material being observed) and replaced with 16 new bone within 24 weeks. The results also suggest that NanoFUSE® DBM is effective in producing a posterolateral fusion by radiographic and manual palpation criteria in an extender mode. This study demonstrates radiographically, histologically, and by manual palpation assessment the ability of NanoFUSE® DBM to induce new bone formation and bridging fusion comparable to autograft in the rabbit spinal fusion model. NanoFUSE® DBM performed well as an autograft extender application and as a stand-alone bone graft substitute in a rabbit model. Similarly, biomechanical data showed comparable values for load, stiffness, extension and energy between NanoFUSE® DBM plus autograft and autograft alone. While animal models cannot be translated into clinically successful human applications, the results of this study suggest further investigation into the clinical use of this material either as a stand-alone bone void filler or as a graft extender is warranted. NanoFUSE® DBM is a registered trademark of Nanotherapeutics, Inc.

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Figure Legends

Figure 1: Representative radiographs of spines from 12-week samples. (A) sham; (B) autograft; (C) NovaBone Putty; (D) NanoFUSE® DBM; (E) NanoFUSE® DBM+autograft.

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Figure 2: Representative radiographs of spines from 24-week samples. (A) sham; (B) autograft; (C) NovaBone Putty; (D) NanoFUSE® DBM; (E) NanoFUSE® DBM+autograft.


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Figure 3: Representative histological slides of spines from 12-week samples. Freshly prepared samples were fixed in 10% formalin, embedded in methyl methacrylate and then sectioned 5m thick. The sections were stained with toluidine blue. (A) Representative slide of a Group 1 (Sham Defect) 12 week implant site – whole implant site photo at 20x magnification; (B) Representative slide of a Group 2 (Autograft (Positive Control)) 12 week implant site – whole implant site photo at 20x magnification. ; (C) Representative slide of NovaBone Putty 12 week implant site – whole implant site photo at 20x magnification; (D) Representative slide of a NanoFuse® DBM 12 week implant site – whole implant site photo at 20x magnification. : (E) Representative slide of a NanoFUSE® DBM with Autograft 12 week implant site – whole implant site photo at 20x magnification.

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Figure 4: Representative histological slides of spines from 24-week samples. Freshly prepared samples were fixed in 10% formalin, embedded in methyl methacrylate and then sectioned 5m thick. The sections were stained with toluidine blue. Slides were fixed in 10% (A) sham; (B) Representative slide of an Autograft Positive Control 24 week implant site – whole implant site photo at 20x magnification; (C) Representative slide of NovaBone Putty 12 week implant site – whole implant site photo at 20x magnification; (D) Representative slide of a NanoFuse® DBM 24 week implant site – whole implant site photo at 20x magnification. ; (E) Representative slide of NanoFUSE® DBM with Autograft 24 week implant site – whole implant site photo at 20x magnification.


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About the LESS Institute’s Dr. Kingsley R. Chin

Dr. Kingsley R. Chin is a board-certified Harvard-trained orthopedic spine surgeon and professor with copious business and information technology experience. He sees a niche opportunity where medicine, business and information technology meet and is uniquely experienced at the intersection of these three professions. He currently serves as Professor of Clinical and Biomedical Sciences at the Charles E. Schmidt School of Medicine at Florida Atlantic University and Professor of Clinical Orthopaedic Surgery at the Herbert Wertheim College of Medicine at Florida International University and has experience as Assistant Professor of Orthopaedics at the University of Pennsylvania Medical School and Visiting Professor at the University of the West Indies.

Learn more about Dr. Chin here and connect via LinkedIn.

Scientific Paper Author & Citation Details

Dr. Kingsley R. Chin, founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin, founder of philosophy and practice of The LES Society and The LESS Institute

Authors

James F. Kirk1, Gregg Ritter1, Michael J. Larson2, Robert C. Waters1, Isaac finger1, John Waters1, John H. Abernethy1, Dhyana Sankar1, James D. Talton1 and Ronald R. Cobb1

Author information

  1. Research and Development Department, Nanotherapeutics, Inc., Alachua, FL

  2. Ibex Preclinical Research, Inc., Logan, UT 84321

References Cited

  1. Goulet, J.A., et al., Autogenous iliac crest bone graft. Complications and functional assessment. Clin Orthop Relat Res, 1997(339): p. 76-81.

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  18. Lee, J.H., et al., Biomechanical and histomorphometric study on the bone-screw interface of bioactive ceramic-coated titanium screws. Biomaterials, 2005. 26(16): p. 3249-57.

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  21. Desikan, R.S., et al., Automated MRI measures predict progression to Alzheimer’s disease. Neurobiol Aging, 2010. 31(8): p. 1364-74.

  22. Glowacki, J., A review of osteoinductive testing methods and sterilization processes for demineralized bone. Cell Tissue Bank, 2005. 6(1): p. 3-12.

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  24. Lomas, R.J., et al., An evaluation of the capacity of differently prepared demineralised bone matrices (DBM) and toxic residuals of ethylene oxide (EtOx) to provoke an inflammatory response in vitro. Biomaterials, 2001. 22(9): p. 913-21

  25. Kirk, J.F., et al., Osteoconductivity and osteoinductivity of NanoFUSE((R)) DBM. Cell Tissue Bank, 2013. 14(1): p. 33-44.

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  30. Fujishiro, Y., L.L. Hench, and H. Oonishi, Quantitative rates of in vivo bone generation for Bioglass and hydroxyapatite particles as bone graft substitute. J Mater Sci Mater Med, 1997. 8(11): p. 649-52.

  31. Oonishi, H., et al., Particulate bioglass compared with hydroxyapatite as a bone graft substitute. Clin Orthop Relat Res, 1997(334): p. 316-25

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  33. Wheeler, D.L., et al., Effect of bioactive glass particle size on osseous regeneration of cancellous defects. J Biomed Mater Res, 1998. 41(4): p. 527-33.

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  44. Xynos, I.D., et al., Gene-expression profiling of human osteoblasts following treatment with the ionic products of Bioglass 45S5 dissolution. J Biomed Mater Res, 2001. 55(2): p. 151-7.

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NanoFUSE® DBM: Bioactive Glass and DBM for Enhanced Bone Healing

By Admin

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NanoFuse is a biologic tech company acquired by Dr. Kingsley R. Chin, through his private equity firm KICVentures.

Background

Bone void fi llers comprised of human demineralized bone matrix (DBM) in a biologically acceptable carrier are an important tool for the orthopedic surgeon. DBM-based bone-void fi llers aid in bone healing, minimize the need for autologous graft material and eliminate donor site complications. NanoFUSE® DBM is a new demineralized bone matrix product that combines the osteoinductive capabilities of DBM with the osteopromotive properties of 45S5 bioactive glass. NanoFUSE® DBM is formulated to reconstitute into a paste, syringeable gel, or putty upon addition of a sterile fl uid, e.g., water for injection (WFI) or sterile saline. NanoFUSE® DBM, provided in single-use 2, 5, and 10cc sizes in a pre-fi lled syringe ready for reconstitution, is both sterile and pyrogen free. The dry product, in single-use syringes, is sterilized post packaging by ionizing radiation (electron beam). At point of use, the surgeon reconstitutes the product with an appropriate sterile solution of his/her choice (e.g. WFI or sterile normal saline). The coated particles rehydrate in less than 30 seconds and do not require mixing to form a uniform paste or putty. The material is then extruded by the surgeon into the appropriate bone voids. Results of studies conducted by both Nanotherapeutics and independent laboratories demonstrate that the osteoinductive capacity of the NanoFUSE® DBM with bioactive glass is preferable to other commercial bone void fi ller implant preparations with only DBM. Using histopathological observation of ectopic bone growth, including the appearance of cartilage-forming and bone-forming cells, the presence of new cartilage, new bone, and new bone marrow provides excellent measures for comparison. Additionally, the inclusion of calcium-based 45S5 bioactive glass, the fi rst humanmade material to release calcium and form a direct chemical bond with tissue, NanoFUSE® DBM produces an exceedingly strong interfacial bond between the graft and adjacent boney tissue within minutes. The original formulation of 45S5 bioactive glass was invented in 1971 (Hench, et al). The capacity for rapid interfacial bonding, which is the defi ning characteristic of a bioactive material, is the result of chemical reactions that take place on the surface of bioactive glass when it is exposed to bodily fl uids. This rapid bone bonding ensures positional stability of the graft during the critical period immediately following surgery. The ability of bioactive glass to rapidly bond with native tissue and trigger the cellular process of healing has prompted its use in an increasing number of clinical settings. NanoFUSE® DBM (K062459), a malleable putty-like bone void fi ller, is indicated for use in general orthopedic procedures (both elective surgeries and trauma injuries). NanoFUSE® DBM is comprised of human demineralized bone matrix and synthetic calcium phosphor-silicate particulate material (45S5 bioactive glass) particles, both coated with Type A gelatin (acid treatment, USP) derived from porcine skin. Gelatincoated particles are packaged dry in a polypropylene syringe, double-wrapped in peel-back pouches, and fi nal packaged in a dust cover paperboard carton. The product packaging is in the form of a luer-lock syringe, with a one-way check valve at the end, in which the device is reconstituted. The product is intended for single-patient use only.

Performance Measures

Cytotoxicity

Cytotoxic effects of NanoFUSE® DBM and the empty syringe assembly (vented syringe, luer lug, check valve fl uid path-way) were evaluated with the test protocol ISO MEM Elution Using L-929 Mouse Fibroblast Cells (also described in the USP 29 <87> Biological Reactivity Tests, In Vitro). NanoFUSE® DBM and the empty syringe assembly did not induce cytotoxicity and no abnormal events such as pH change or debris were noted in this assay. NanoFUSE® DBM is non-cytotoxic.

Mutagenicity

Mutagenicity was evaluated with the test protocol Bacterial Mutagenicity Test – Ames Assay, which evaluates the mutagenicity potential of a test article by measuring its ability to induce back mutations at selected loci of several strains of bacteria in the presence and absence of microsomal enzymes by a method compliant with the requirements specifi ed in ISO 10993- 3:2003. It was also determined that NanoFUSE® DBM did not cause increases in point mutation, exchanges or deletions. NanoFUSE® DBM is considered non-mutagenic.

Pyrogenicity

Since NanoFUSE® DBM includes a biologic component, information regarding endotoxin level and pyrogenicity are included in the release specifi cation for each manufactured lot. Intact, granular samples of NanoFUSE® DBM are submitted to an independent test laboratory to perform Limulus Amebocyte Lysate (LAL) testing on a lot by lot basis, using the Kinetic Chromogenic Method. To conform to current USP standards, blood-contacting devices must show endotoxin levels of <20 EU/device or <0.5 EU/mL. NanoFUSE® DBM may be considered non-pyrogenic.

Sensitization

Sensitization of NanoFUSE® DBM was evaluated using the test protocol ISO Guinea Pig Maximization Sensitization Test Method for Biomaterial Extracts which evaluates if the material stimulates the immune system to produce an allergic re-sponse. Since the response is usually due to leachable substances in the material, extracts are used for administration to guinea pigs. Extraction of NanoFUSE® DBM was performed according to the standard ANSI/AAMI/ISO 10993-12 Sample Preparation and Reference Materials. Freund’s Complete Adjuvant (FCA) and sodium lauryl sulfate (SLS) were used to enhance a potential weak sensitizing effect. NanoFUSE® DBM showed no sensitization response and was equivalent to negative controls.

Systemic Toxicity

Systemic toxicity of NanoFUSE® DBM was evaluated with the test protocol ISO Acute Systemic Injection Test which was conducted in accordance with the ISO 10993-11:1993, Biological Evaluation of Medical Devices – Part 11: Tests for Sys-temic Toxicity and USP 29, 2006. This test screens for potential toxic effects as a result of a single-dose systemic injection in mice. None of the NanoFUSE® DBM treated animals presented adverse clinical signs at any of the observation periods and none of the animals lost in excess of 2 g body weight over the course of the study. NanoFUSE® DBM does not elicit systemic toxicity.

Intracutaneous Reactivity

Intracutaneous reactivity of NanoFUSE® DBM was evaluated with the test protocol ISO Intracutaneous Reactivity Test which was conducted in accordance with the ISO 10993-10:2002, Biological Evaluation of Medical Devices, Part 10: Tests for Irritation and Delayed-type Hypersensitivity. This test evaluates chemicals that may leach out of or that are extracted from the test article are capable of causing local irritation in the dermal tissues of a rabbit. The mean test score both for NanoFUSE® DBM cottonseed-oil extract and for control extract was 0 (out of 0 to 4). NanoFUSE® DBM is considered a non-irritant.

Implantation

Intramuscular reactivity of NanoFUSE® DBM was evaluated with the test protocol ISO Intramuscular Implant Test 4 Week Duration in Rabbits which was conducted in accordance with the ANSI/AAMI/ISO 10993-6:1995, Biological Evaluation of Medical Devices, Part 6: Tests for Local Effects after Implantation. This test evaluates local toxic effects of a biomaterial in direct contact with living muscular tissue of the rabbit for four weeks. All animals survived to the scheduled endpoint of the study and no abnormal clinical signs were noted with all implants and implant sites appearing macroscopically normal. Tissue reactions such as granulation tissue with poly- and mononuclear cell infi ltration, fi broblasts, neovascularization, and capsule formation are common and expected in this model. Comparison of NanoFUSE® DBM to an inorganic material differential scoring reported NanoFUSE® DBM as a moderate irritant. Tissue reaction in the muscle tissue is not unexpected when using an implant made of organic fragmented material such as NanoFUSE® DBM. Human demineralized bone matrix (DBM) is xenograft material in a rabbit model.

Osteoconductivity: Critical-size Defect in the Rabbit Radius

Nanotherapeutics conducted a GLP compliant study at an independent test laboratory to evaluate the proprietary formulation of NanoFUSE® DBM for enhancing bone formation and subsequent healing of a criticalsize defect in the rabbit radius. A comparison was made among NanoFUSE® DBM, a FDA compliant Predicate Device, and autogenous bone graft, which is the gold standard in clinical practice. The Predicate Device for comparison was a DBM paste with inert porcine collagen carrier. In the comparison study, 54 male, New Zealand White Rabbits were assigned to one of fi ve study arms (n=6 for the con-trol and n=12 animals for each test article arm; Predicate Device, NanoFUSE® DBM, NanoFUSE® DBM w/o DBM, and NanoFUSE® DBM w/o bioactive glass). Each animal had one 1.5 cm defect surgically created in one of its front limbs and each animal was assigned one treatment. Each defect was fi lled with one of the four test articles or autogenous bone as a positive control. The autogenous control performed as expected with 5 out of 5 fusions (for animals completing the full 12 weeks). The Predicate Device had one animal scoring “likely fused” based on radiographic results and 11 animals without fusion. The most likely explanation for this outcome is that human DBM in the rabbit model would elicit an immune response that interfered with complete healing. Each of the remaining test articles had one animal that was scored as “fused” based on radiographic interpretations. All test articles and the Predicate Device produced less callus than the autogenous bone (p<0.001, Student’s t test, 2 tail, heteroscedastic). However, NanoFUSE® DBM produced more callus than the Predicate Device (p<0.159). The explanted tissue was decalcifi ed and sectioned for histology. Cross sections were taken at the proximal, midline, and distal ends of the explant. These slides were evaluated on the presence or absence of the following characteristics: 1) original DBM, 2) bone callus, 3) estimate % of normal bone involved in callus, 4) chondroblasts/ chondrocytes, 5) osteoblasts/ osteocytes, 6) cartilage/osteoid, 7) new bone, 8) bone marrow, 9) connective tissue admixed with bone elements, 10) foreign material. The histological fi ndings for NanoFUSE® DBM were substantially equivalent to those of the Predicate Device. Studies above were conducted in compliance with U.S. Food and Drug Administration Good Laboratory Practices regulations set forth in 21 CFR part 58. Nanotherapeutics contracted an independent test laboratory to oversee the long-term implantation study. Radiography and radiographic interpretations were performed by this facility. Histology preparations and histopathology readings were performed at another independent test laboratory. Scanning and digital analysis of radiographs were performed by Nanotherapeutics.

Osteoinductivity: Rodent Ectopic Implant Assay

The rodent ectopic (RE) bone assay is considered the “gold standard” of assays for osteoinductivity measurement (versus in vitro cell-based assays or antibodybased assays for bone morphogeneic proteins, McKay, et al. 2006, p. 10; ASTM F04.4 Division 2003). In brief, test materials are surgically implanted into intramuscular pouches. After 28 days, the implant site is excised and prepared for histolopathological examination for evidence of new bone formation. The ability of materials to induce bone formation in non-boney sites is characterized as osteoinduction. The following four materials were submitted for the RE assay: NanoFUSE® DBM, DBM raw material used to produce NanoFUSE® DBM, Osteofi l® RT DBM Paste, and Accell® DBM100. All test articles were tested either as dry powders to which, after weighting, several drops of saline were added to aid in handling or, in the case of Accell® DBM100, tested as received. Athymic “nude” male mice were implanted with 25 mg of test material in a bluntly-dissected muscle pouch in each hind leg. After 28 days, the explanted tissues were subjected to a thorough histopathological examination. Each explant was scored as either positive or negative for evidence of ectopic ossifi cation. Determination of ectopic ossifi cation was made using the following fi ve criteria: 1) presence of chondroblasts/ chondrocytes; 2) presence of osteoblasts/osteocytes; 3) presence of cartilage/osteoid; 4) presence of new bone; and 5) presence of bone marrow. Each implant site was graded on a scale from 0 to 4 for evidence of ectopic ossifi cation as follows: 0 = no evidence; 1 = 1-25% of fi eld shows evidence; 2 = 26-50% of fi eld shows evidence; 3 = 51-75% of fi eld shows evidence; 4 = 76-100% of fi eld shows evidence. Test materials for which at least one implant site scored 1 or higher were considered osteoinductive.

Figure 1 depicts the incidence of implantation sites exhibiting evidence of bone marrow cells, of osteoblasts/osteocytes, and of new bone formation. NanoFUSE® DBM and Accell® DBM100 each had only one implant site that scored a 0 on the three criteria exhibited in Figure 1. Notably, Osteofi l® RT DBM Paste scored a 0, for all three criteria, at 5 out of the 10 implant sites. Although they were scored similarly, there was a distinct and important difference between the osteoinductive performance of the NanoFUSE® DBM and Accell® DBM100; NanoFUSE® DBM produced more bone cells, bone, and marrow than Accell® DBM100. Figures 2 and 3 below are two different magnifi cations of an exemplar histograph for the NanoFUSE® DBM study arm. Over half of the new bone formation evidence detected for the Accell® DBM100 implant sites was related to presence of chondroblasts/chondrocytes and presence of cartilage/osteoid only. If one considers just the scores that indicate the presence of osteoblasts/ osteocytes, the presence of new bone, and the presence of bone marrow, then Accell® DBM100 would have scored exactly the same as Osteofi l® RT DBM Paste even though much of the new bone formation in Accell® DBM100 was non-mineralized. Both of these other two clinically available DBM bone void fi llers had a much lower incidence of sites exhibiting key characteristics of osteoinduction, namely the presence of osteoblasts/osteocytes, new bone, and bone marrow when compared to the NanoFUSE® DBM study arm.

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Conclusion

Ready to use or ready to mix bone void fi llers are chosen over native DBM because of their superior handling characteristics. The presence of a carrier, such as porcine gel, makes the fi ller a putty rather than a clump of DBM particles with little cohesion. The results of these studies of NanoFUSE® DBM with bioactive glass demonstrate superior bone formation to Osteofi l® RT DBM Paste or Accell® DBM100. NanoFUSE® DBM is a bone-void fi ller that combines 45S5 bioactive glass, a known osteoconductive and osteopromotive material, with DBM in a porcine gelatin carrier. As such, NanoFUSE® DBM combines the osteoconductive properties of bioactive glass with the osteoinductive properties of DBM, showing superior bone healing results when compared to Osteofi l® RT DBM Paste or Accell® DBM100. Most notably, the rodent ectopic assay demonstrates that DBM in combination with bioactive glass provides comparatively better osteoinductivity than the DBM-only products, as measured by the actual amount of bone cells, bone, and bone marrow observed. NanoFUSE® DBM has been implanted in more than 1200 patients with no adverse events reported (data derived from graft tracking records). More than 270 surgeons have used the device and reported procedures including: shoulder, arm, hand/wrist, leg/hip, knee, and foot/ankle surgeries (both primary and revision; both trauma and elective).

References

ASTM F04.4 Division. Draft Standard: Standard Guide for the Assessment of Bone Inductive Materials. Wolfi nbarger, Revision Date: 11/18/2003

Hench, L.L., et al. Bonding mechanisms at the interface of ceramic prosthetic materials. J. Biomed. Mater. Res. Symp. 1971;5(6):117-141.

McKay, W.F., et al. “The science of rhBMP-2”, Quality Medical Publishing, 2006, pp. 24-34

McKay, W.F., et al. “The science of rhBMP-2”, Quality Medical Publishing, 2006, p 10.

Bibliography

Adkisson, H.A., et al. A rapid quantitative bioassay of osteoinduction. J Orthopedic Res, 2000, 18:503-511.

Anajarwalla, N.K., et al. Posterior spinal fusion using bone graft substitutes. Intl. Soc. Lumbar Spine Ann. Meeting. Ade-laide, Australia. April, 2000.

Cunningham, B.W., et al. The use of bioglass for posterolateral spinal arthrodesis and iliac crest donor site repair – An In Vivo Sheep Model. Transactions ORS 45th Annual Meeting. 1999;p.357.

Elshahat, A., et al. The use of Novabone and Norian in cranioplasty: A comparative study. J. Craniofac. Surg. 2004;15(3):483-489.

Fujishiro, Y., et al. Quantitative rates of in vivo bone generation for Bioglass® and hydrosyapatite particles as bone graft substitute. J. Mater. Sci. – Mater. Med. 1997;8:649-652.

Gaisser, D.M., et al. Particulate bioactive glass in the repair of iliac crest autograft donor sites. Transactions Sixth World Biomaterials Congress. 2000;23:260.

Kawanabe, K., et al. Effects of injecting massive amounts of bioactive ceramics in mice. J. Biomed. Mater. Res. 1991;25(1):117-128.

Kotani, S., et al. Enhancement of bone bonding to bioactive ceramics by demineralized bone powder. Clin. Orthop. Relat. Res. 1992;(278):226-234.

Oonishi, H. Particulate bioglass compared with hydroxyapatite as a bone graft substitute. Clin. Orthop. Relat. Res. 1997;334:316-325.

Pajamaki, K.J., et al. Induction of new bone by allogeneic demineralized bone matrix combined to bioactive glass composite in the rat. Ann. Chir. Gynaecol. Suppl. 1993;207:137-143.

Piétrement, O. and E. Jallot. AFM mechanical mapping at the interface between a bioactive glass coating and bone. Nan-otechnology. 2002;13:18-22.

Rezwan, K, et al. Biodegradable and bioactive porous polymer/inorganic composite scaffolds for bone tissue engineering. Biomaterials. 2006;27:3413-3431.

Urist M.R. Bone: Formation by autoinduction. Science. 1965;150:893-899.

Vallet-Regi, M., et al. Bioactive glasses as accelerators of apatite bioactivity. J. Biomed. Mater. Res. 2003;66A:580-585.

Wheeler D.L., et al. Assessment of resorbable bioactive material for grafting of critical-size cancellous defects. J. Orthop. Res. 2000;18:140–8.

Wheeler, D.L., et al. Effect of bioactive glass particle size on osseous regeneration of cancellous defects. J. Biomed. Mater. Res. 1998;41(4):527-533.

Wilson J., et al.. Spinal fusion using titanium spacers with bioglass and autogenous bone: a comparative study in sheep. In Bioceramics 10. 1997; p. 65-70. L. Sedel and C. Ray (Eds). Elsevier Science. New York.

Wilson, J., et al. Toxicology and biocompatibility of bioglasses. J. Biomed. Mater. Res. 1981;15(6):805-817

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About the LESS Institute’s Dr. Kingsley R. Chin

Dr. Kingsley R. Chin, founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin, founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin is a board-certified Harvard-trained orthopedic spine surgeon and professor with copious business and information technology experience. He sees a niche opportunity where medicine, business and information technology meet and is uniquely experienced at the intersection of these three professions. He currently serves as Professor of Clinical and Biomedical Sciences at the Charles E. Schmidt School of Medicine at Florida Atlantic University and Professor of Clinical Orthopaedic Surgery at the Herbert Wertheim College of Medicine at Florida International University and has experience as Assistant Professor of Orthopaedics at the University of Pennsylvania Medical School and Visiting Professor at the University of the West Indies.

Learn more about Dr. Chin here and connect via LinkedIn.

Disclaimer: NanoFUSE® DBM is a registered trademark of Nanotherapeutics, Inc. Osteofi l® RT DBM Paste is a registered trademark of RTI Biologics, Inc. Accell® DBM100 is a registered trademark of Integra Orthobiologics (subsidiary of Integra Lifesciences Corporation). Bioglass® is a registered trademark of the University of Florida.

Decreasing Radiation Dose With FluoroLESS Standalone Anterior Cervical Fusion

By Dr. Kingsley Chin

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Scientific Paper

Kingsley R. Chin, MD, Fabio J.R. Pencle, MB BS, Jason A. Seale, MB BS

Interested medical professionals can read through the full paper, as published in the Journal of Spine Surgery, here.

Study Design

Level III

Objective

Adjacent segment disease and dysphagia remain concerns of anterior cervical discectomy and fusion (ACDF) with fixation using anterior cervical plates (ACPs). The authors aim to demonstrate the feasibility, outcomes and fusion rate of a standalone PEEK cage in the outpatient setting.

Methods

The medical records of 48 consecutive patients undergoing single level standalone ACDF (S-ACDF) (Group 1) were compared to our control group of 49 patients who had single-level ACDF with ACP (Group 2). Outcomes assessed included VAS neck and arm, NDI scores, and radiation dose.

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Results

Forty eight patients in Group 1 (S-ACDF) and 49 patients in Group 2 (ACDF-ACP). No statistical differences in gender, age or BMI were found between groups, p=0.286, 0.691 and 0.947 respectively. There was no intergroup statistically significant difference in preoperative and postoperative outcomes. Mean radiation dose in group 1 of 24.1+/-8.2mAS and 2.0+/-0.7mSv was significantly less compared to group 2 which was 29.8+/-5.4 and 2.5+/-0.5mSv, p<0.001. The average radiation dose for single level fusion in Group 1 was 15.6+/-1.5 mAs and 1.3+/-0.1mSv this is compared to average radiation dose in Group 2 of 27.8+/-3.9mAs and 2.3+/-0.3mSv, p=0.001. The average radiation dose for two level fusion in Group 1 was 30.9+/-3.5 mAs and 2.6+/-0.3mSv this is compared to average radiation dose in Group 2 of 33.9+/-6.0 and 2.9+/-0.5mSV, p=0.012.

Conclusion

In the outpatient setting, S-ACDF has shown statistically significant intergroup difference in overall radiation dose, as well as single and two-level fusions, (p<0.001). We conclude that S-ACDF can decrease overall radiation exposure to patients. This is comparable to single level ACDF-ACP in the outpatient setting.

About Author Dr. Kingsley R. Chin

Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin, Founder of philosophy and practice of The LES Society and The LESS Institute

Dr. Kingsley R. Chin is a board-certified Harvard-trained Orthopedic Spine Surgeon and Professor with copious business and information technology exposure. He sees a niche opportunity where medicine, business and info. tech meet – and is uniquely educated at the intersection of these three professions. He has experience as Professor of Clinical Biomedical Sciences & Admissions Committee Member at the Charles E. Schmidt College of Medicine at Florida Atlantic University, Professor of Clinical Orthopedic Surgery at the Herbert Wertheim College of Medicine at Florida International University, Assistant Professor of Orthopaedics at the University of Pennsylvania Medical School, Visiting Spine Surgeon & Professor at the University of the West Indies, Mona, and Adjunct Professor of Clinical Biomedical Sciences at the University of Technology, Jamaica.

Learn more about Dr. Chin here and connect via LinkedIn.

About Less Exposure Surgery

Less Exposure Surgery (LES) is based on a new philosophy of performing surgery, leading the charge to prove through bench and clinical outcomes research that LES treatment options are the best solutions – to lowering the cost of healthcare, improving outcomes and increasing patient satisfaction. Learn more at LESSociety.org.

The LES Society philosophy: “Tailor treatment to the individual aiding in the quickest recovery and return to a pain-free lifestyle, using LES® techniques that lessen exposure, preserve unoffending anatomy and utilize new technologies which are safe, easy to adopt and reproducible. These LES®techniques lessen blood loss, surgical time and exposure to radiation and can be safely performed in an outpatient center. Less is more.” – Kingsley R. Chin, MD

About The LESS Institute

The LESS Institute is the world leader center of excellence in Less Exposure Surgery. Our safe, effective outpatient treatments help patients recover quickly, avoid expensive hospital stays and return home to their family the same day. Watch our patient stories, follow us on Facebook and visit TheLESSInstitute.com to learn more.

Scientific Paper Author & Citation Details

Authors

Kingsley R. Chin, MD1,2,3,Fabio J.R. Pencle, MB BS3, Jason A. Seale, MB BS3

Author information

1. Herbert Wertheim College of Medicine at Florida International University

2. Charles E. Schmidt College of Medicine at Florida Atlantic University

3. Less Exposure Surgery (LES) Society

4. Less Exposure Surgery Specialists Institute (LESS Institute).