The purpose of this study is to evaluate the safety of the S.T.A.R. device for patients with bilateral disease.

The specific objectives are to show that the safety data of the S.T.A.R. ankle arthroplasty is similar for treatment of single ankle disease (as defined in the pivotal study) and bilateral ankle disease. The bilateral disease may be identified at the time of enrollment or may have progressed after enrollment and treatment of the first ankle in the pivotal study.

Inclusion Criteria:

• Moderate or severe pain, loss of mobility and function of the ankle
• Primary arthrosis, post traumatic arthrosis or rheumatoid arthrosis
• At least six months of conservative treatment for severe ankle conditions
• Bilateral ankle disease that have not been enrolled in the pivotal study or single ankle disease and enrolled in the pivotal study but have subsequently developed ankle disease in the contralateral ankle and require surgical intervention
• Willing and able to give informed consent

Exclusion Criteria:

• Patients who have not reached skeletal maturity
• Active or prior deep infection in the ankle joint or adjacent bones
• Prior arthrodesis at the involved site
• History of prior mental illness or patient demonstrates that their mental capacity may interfere with their ability to follow the study protocol
• Obesity (weight greater than 250 lbs)
• History of current or prior drug abuse or alcoholism
• Any physical condition precluding major surgery
• Prior surgery and/or injury that has adversely affected the ankle bone stock
• Severe osteoporotic or osteopenic condition or other conditions that may lead to inadequate implant fixation in the bone
• Insufficient ligament support