Augment® Injectable Bone Graft Compared to Autologous Bone Graft as a Bone Regeneration Device in Hindfoot Fusions

KEY INCLUSION CRITERIA:

• at least 18 years old and considered skeletally mature

• diagnosed with degenerative joint disease (DJD) affecting the hindfoot due to acongenital or acquired deformity, osteoarthritis, rheumatoid arthritis, post-traumatic arthritis or ankylosing spondylitis of the ankle, subtalar, calcaneocuboid,and/or talonavicular joints

• requires one of the following hindfoot fusion proceduress with supplemental bonegraft/substitute: ankle fusion (tibiotalar), subtalar fusion (talocalcaneal),calcaneocuboid fusion, talonavicular fusion, triple arthrodesis (subtalar,talonavicular and calcaneocuboid joints) OR double fusions (any combination of any twoof the following: subtalar, talonavicular and calcaneocuboid joints)

• fusion site able to be rigidly stabilized with no more than 3 screws across the fusionsite

• supplemental pins or staples allowed

• supplemental screws external to the fusion site(s) allowed

• signed informed consent document, independent, ambulatory, and can comply with allpost-operative evaluations and visits

KEY EXCLUSION CRITERIA:

• undergone previous fusion surgery at the proposed location, i.e., revision of a failedfusion

• more than one previous procedure at the involved joints

• retained hardware spanning the joint(s) intended for fusion

• procedure anticipated to require plate fixation (including claw plates), IM nails ormore than 3 screws to achieve rigid fixation based on pre-op planning

• procedure expected to require more than 9cc of graft material based on pre-op planning

• procedure expected to require structural bone graft, allograft, bone graft substitute,platelet rich plasma (PRP) or bone marrow aspirate

• procedure expected to require a pantalar fusion, i.e., fusion of ankle plus allhindfoot joints (talonavicular, subtalar, and calcaneocuboid) or an ankle fusion incombination with any hindfoot fusion

• radiographic evidence of bone cysts, segmental defects or growth plate fracture nearthe fusion site that could negatively impact the proposed fusion procedure

• tested positive or been treated for a malignancy in the past or is suspected of havinga malignancy or currently undergoing radio- or chemotherapy treatment for a malignancyanywhere in the body, whether adjacent to or distant from the proposed surgical site

• pre-existing sensory impairment, e.g., diabetics with baseline sensory impairment,which limits ability to perform objective functional measurements and may be at riskfor complications

• diabetics not sensitive to the 5.07 monofilament (Semmes-Weinstein) are to beexcluded

• metabolic disorder known to adversely affect the skeleton other than primaryosteoporosis or diabetes, e.g., renal osteodystrophy or hypercalcemia

• use of chronic medications known to affect the skeleton, e.g., glucocorticoid usage > 10mg/day

• pre-fracture neuromuscular or musculoskeletal deficiency which limits the ability toperform objective functional measurements

• physically or mentally compromised, e.g., current treatment for a psychiatricdisorder, senile dementia, Alzheimer's disease, etc., to the extent that theInvestigator judges the subject to be unable or unlikely to remain compliant

• allergic to yeast-derived products or bovine collagen or other bovine-sourced products

• received an investigational therapy within 30 days of proposed surgery or during thefollow-up phase of the study

• is a prisoner, known or suspected transient or a history of drug/alcohol abuse withinthe 12 months prior to screening

• pregnant or intending to become pregnant within 12 months of the study procedure

• morbidly obese defined as BMI > 45 kg/m2

• currently has an acute infection at the surgical site