Hip arthrodesis: current indications and techniques.

The management of young adults with severe osteoarthritis of the hip remains a problem because of the increased failure rates of total hip arthroplasty (THA) as well as the prospect of multiple revisions in this population. Although hip arthrodesis is not perceived favorably as an alternative by most orthopaedic surgeons or patients because of the presumption of less than optimal functional outcomes, it is a viable technique, especially for younger patients with a recent history of local infection and/or trauma. With current internal fixation techniques, a fusion rate >80% can be achieved with maximal preservation of bone stock. Proper patient selection and optimal arthrodesis position (flexion of 20 degrees to 30 degrees, adduction of 5 degrees, external rotation of 5 degrees to 10 degrees, and limb-length discrepancy <2 cm) are essential for a successful, long-term result. Back and ipsilateral knee pain are the most common complaints leading to secondary conversion of a hip fusion to a THA. Symptoms improve markedly after conversion. Survivorship of the conversion THA is comparable to that of a primary THA when the patient is older than 50 years of age and multiple surgical procedures have been avoided. However, the procedure can be technically challenging and has a high risk of postoperative complications.