Augment™ Injectable Bone Graft Compared to Autologous Bone Graft in Foot and Ankle Fusions

Study Objective: To demonstrate equivalent clinical and radiologic outcomes as "gold standard" (ABG) in a representative clinical model (foot and ankle fusions)

Study Hypothesis: Augment™ Injectable is an equivalent bone grafting substitute to autologous bone graft in applications as shown by superiority analysis for safety and non-inferiority analysis for effectiveness

Study Rationale: Evaluate a fully synthetic bone graft material to facilitate fusion in conditions or injuries requiring bone graft in a representative clinical fusion model and thus the opportunity to provide equivalent union rates as ABG without necessitating an additional invasive procedure to harvest the graft

Musculoskeletal problems are pervasive throughout the population in all age groups and in both sexes. Half of Americans will need services for fractures at some point in their lifetime according to a widely published article presented at the 2003 annual meeting of the American Academy of Orthopedic Surgeons (AAOS). Many musculoskeletal problems, such as fractures and non-unions require bone graft to ensure adequate bone healing. One of the most widely used options for bone graft is autologous bone however; clinical difficulties have been associated with ABG (autologous bone graft). Most of these difficulties result from the harvest of the bone graft, including increased operative time, hospital stay and cost, increased blood loss, post-operative pain, risk of infection and/or fracture. The morbidity associated with ABG and its limited amount available to be harvested has directed surgeons to look for a better alternative for a chemotactic, mitogenic, and angiogenic bone graft substitute as an alternative for fracture augmentation to accelerate healing (St. John et al, 2003).

Currently, there are no generally accepted alternatives to ABG for fusion procedures of the foot or ankle. In order to demonstrate a product's effectiveness, it is necessary to show equivalence to autogenous bone graft in terms of safety and effectiveness. The purpose of this study is to examine the safety and efficacy of Augment™ Injectable Bone Graft (Beta-TCP/ Bovine Collagen matrix + rhPDGF-BB) in facilitating equivalent mean time to union as ABG in this foot and ankle fusion model. Our hypothesis is that the intraoperative application of Augment™ Injectable Bone Graft (Augment™ Injectable) in foot and ankle fusion procedures will demonstrate at least equivalent efficacy to that of the gold standard of autogenous bone graft while avoiding the trauma and sequelae associated with an additional surgical procedure.

• Device: Augment™ Injectable
  Beta-TCP/Bovine Collagen matrix + rhPDGF-BB
• Procedure: Standard of care
  Autologous Bone Graft

• Active Comparator: Group 1
  Standard Rigid Fixation plus Autograft
  Intervention: Procedure: Standard of care
• Experimental: Group 2
  Standard Rigid Fixation plus Augment™ Injectable
  Intervention: Device: Augment™ Injectable

Inclusion Criteria:

• Bone defect in the hindfoot or ankle requiring fusion with supplemental bone graft/substitute, requiring one of the following procedures:

  • Ankle joint fusion
  • Subtalar fusion
  • Calcaneocuboid fusion
  • Talonavicular fusion
  • Triple arthrodesis (subtalar, talonavicular and calcaneocuboid joints)
  • Double fusions (any combination of any two of the following: subtalar, talonavicular and calcaneocuboid joints)

Exclusion Criteria:

• Previous fusion surgery of the proposed site
• Patient uses chronic medications known to affect the skeleton (e.g., glucocorticoid usage >10mg/day)
• Pregnant or a female intending to become pregnant during this study period
• Morbidly obese (BMI >45 kg/m2)
• Currently has untreated malignant neoplasm(s), or is currently undergoing radio- or chemotherapy or has been diagnosed with hypercalcemia.