3D X-ray Motion Analysis of Ankle-foot Motion After Total Ankle Arthroplasty

INCLUSION CRITERIA: * Between 18 to 79 years of age. Additional Inclusion criteria for mobile-bearing ankle prosthesis user group: * Able to walk independently with their prosthesis at different self-selected speeds * Implanted with Stryker Scandinavian Total Ankle Replacement (STAR) prosthesis at least one year prior to enrollment * Pain free and radiologically normal * Able to walk at preferred walking speed without an assistive device (e.g., cane, crutches, etc.) Additional Inclusion criteria for control group: * Within 3 years of age of one of the mobile-bearing ankle prosthesis user participants * Same gender as the matched mobile-bearing ankle prosthesis user participant * Not have a history of major musculoskeletal injuries * Not have a history of major neuromuscular injuries Additional Inclusion criteria for fixed-bearing ankle prosthesis users: * Able to walk independently with their prosthesis at different self-selected speeds * Implanted with INBONE 2 prosthesis at least one year prior to enrollment * Pain free and radiologically normal * Able to walk at preferred walking speed without an assistive device (cane, crutches, etc.) EXCLUSION CRITERIA: * Have dementia or an inability to give informed consent * Have significant or chronic loss of hip or knee joint motion * Have any subtalar or hindfoot fusion * Have a history of dizziness and/or balance problems * Have had any additional x-ray exposures in the past year that would put beyond the recommended annu…