Hydroxyapatite-coated hip prostheses:Difficulties with revision in 4 cases

The introduction of hydroxyapatite ceramic (HAC) coating on hip implants in 1985 (Furlong and Osborn 1991) was hailed as a major advancement for fixation of uncemented prostheses. A problem that is now becoming evident is the extraction of these securely fixed prostheses for purposes of revision. We report on 4 patients who have had HAC-coated prostheses implanted (2 as revision procedures and 2 at primary hip replacement) who had either continuing pain or a proven infection, so that it became necessary to carry out a revision hip arthroplasty. The prostheses were well-fixed and difficult to remove. A transfemoral, longitudinal osteotomy was used in 3 cases.