Clinical Evaluation of Integra® Cadence™ Total Ankle System in Primary Ankle Joint Replacement (CADENCE)

Inclusion Criteria: * The patient is skeletally mature. * The patient qualifies for primary Total Ankle Replacement (TAR) per the surgeon and has a diagnosis of one of the following: Primary Arthritis (e.g. Degenerative Disease), Secondary Arthritis (e.g. Post-Traumatic, Avascular Necrosis, if minimally 2/3 of the talus is preserved), or Systemic Arthritis of the ankle (e.g. Rheumatoid Arthritis, Hemochromatosis). * The patient is willing and able to complete scheduled follow-up visits, evaluations and questionnaires as described in the Informed Consent. * The patient reads, understands and signs the Institutional Review Board (IRB) approved Informed Consent. Exclusion Criteria: * The patient is Morbidly Obese (defined by Body Mass Index (BMI) \> 40 or BMI of 35 - 40 with significant medical problems caused by or made worse by their weight). * The patient has one of the following conditions, which could compromise the affected limb: ankle arthrodesis with malleolar exeresis, severe neurological (Charcot's Arthropathy) or vascular disease, loss of musculature or neuromuscular compromise. * The patient has an active local/systemic infection that may affect the prosthetic joint or has a recent history of infection. * The patient has a condition that may impair proper wound healing (e.g., poor soft tissue envelope). * The patient is pregnant or plans to become pregnant during the follow up period. * The patient has a metabolic disorder or disease that may compromise bone quality (e.g. arthrogryposis etc.), physiological or anatomical anomalies, and/or malignancy/local bone tumors. * The patient has inadequate neuromuscular status (e.g., prior paralysis, severe neuropathy). * The patient has a known sensitivity or allergic reaction to one or more of the implanted materials.