Care of the Foot and Ankle DaVinci Christopher W. DiGiovanni, MD Chief, Division of Foot and Ankle Professor & Program Director, Dept. Orthopaedic Surgery The Warren Alpert School of Medicine at Brown University Providence, RI, USA
An Introduction to Foot & Ankle Surgery Anatomy and Biomechanics Pathophysiology: What We Treat Foot/Ankle Care: What We Do The Problems We Currently Face The Solutions We Currently Use: Bone Graft in Foot & Ankle Surgery Looking Towards the Future: Augment Pivotal Study Overview Surgical Technique Q & A
The Foot and Ankle: A Complex Machine Inseparable! 26 bones and joints, working in concert Our ever-present, immediate contact with the environment Usually never complain! More work/unit area than anywhere else small surface area Stress = 1.5x BWwalking, 5-7x BW running, up to 10x BW jumping Several Million cycles/year
I Have Foot Pain Estimated that 40% of U.S. adults experience foot pain (problems) at some point in their lives. Am Fam Physician 2007;76:975-83. Karasick D, Wapner KL. AJR Am J Roentgenol 1990;155:119-23.
Orthopedic Foot and Ankle Specialists MDs, orthopedic surgeons Usually fellowship trained specifically for the foot and ankle WHAT DO WE CARE FOR? Sports Injuries: sprains and strains Fractures Congenital or Acquired deformity Nerve Disorders Tendinitis Diabetic Foot Conditions Infections, Tumors, etc. ARTHRITIS
Arthritis of the Foot & Ankle COMMON from many causes: OA, Inflammatory, Gout, Instability, Infectious Neuropathic, Congenital Post-Traumatic most common A deterioration of the cartilage lining within a joint space Can affect a single or multiple joints
TREATMENT OPTIONS For Arthritis Activity Modification Physical Therapy Medications, e.g. NSAIDs Cortisone Injection Footwear/Orthotics/Bracing Arthroscopy/Joint Debridement Corrective Osteotomy Distraction Arthroplasty Osteochondral Grafting Arthroplasty (Ankle) Arthrodesis (Fusion)
FUSION is the Gold Standard
6 wk XR 12 wk CT
1 Year Out
Foot and Ankle Fusion Procedures 14000 12000 10000 8000 6000 4000 2000 0 Ankle Triple Sub TAA 2001 2002 2003 Annual growth: 7% over past 5 years @ 80,000 in 2008 Projected 100,000 by 2011 Source: Ortho Fact Book 2005 Knowledge Enterprises
Non-Union STILL a Major F/A literature: @ 10% Concern immeasurable Much higher (16-41%) in high risk groups: Smokers Diabetics Revision surgery Post-traumatics Both a mechanical and biological problem Frey et al, FAI, 1994, Myerson et al 2000, Easley et al, JBJS, 2000, Thordarson et al 2003, Haddad et al, 2007
Risk Factors for Post-Surgical NONUNION Patient Factors Smoking Obesity Impaired Vascular Supply Diabetes Neuropathic Joint Local Factors Previous Open Fracture Articular Fractures (Pilon, Talus, Calcaneus) Avascular Necrosis of the Talus H/O Infection
Typically, Autologous Bone Graft (ABG) has been used to enhance fusion rates Stimulates the biological healing process Fills any joint irregularities (voids/gaps) Acts as a scaffold for new bone formation Can provide structural support in some cases
Disadvantages of Using ABG Harvest site pain and morbidity Other complications (up to 31% with ICBG) Increased operative time, anesthesthetic time, blood loss Amount and potency of graft material very variable However, ABG remains the standard because of its positive biological impact on the healing process
Some ABG Alternatives Allograft Synthetics e.g., CaPO4, CaSO4 Collagen Sponges Platelet Gels None of the above have clearly demonstrated equal or greater effectiveness to ABG
Augment Bone Graft North American Foot & Ankle Fusion Study Prospective RCT comparing a new BGS to the current standard of care Hypothesis: equivalent efficacy and superior safety to ABG Potential Benefits: Surgical time Anesthesia time Blood Loss Graft site pain Graft site morbidity
Augment Study Overview Largest PRCT to date involving rhgf in foot and ankle application 37 sites across the US and Canada All investigators are Foot & Ankle specialists 436 patients enrolled Treatment randomized 2:1 (Augment: ABG) 1 endpoint: Fusion at 24 weeks, as evaluated by CT scan All radiographic evaluations performed by a blinded independent musculoskeletal radiologist
Augment Study Demographics Male: 50% Female: 50% Age: Mean = 56 years Range = 19-86 years Tx/Control: Augment: 66% ABG: 34% Patients w/ 1 or more risk factors: 73% Smoker/Smoking History: 49% Diabetic: 12% BMI >30: 40%
Augment Study Demographics Fusion Type Ankle 38% Subtalar 27% Triple 25% T-N 7% C-C 2% Other 1% ABG Harvest Site Proximal Tibia 51% Distal Tibia 15% Calcaneus 13% Iliac Crest 11% Other 10%
Demonstrative Surgical Video http://www.extremeimedia.com/bio_video
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