MIGRATION AND WEAR OF A HYDROXYAPATITE-COATED HIP-PROSTHESIS

A consecutive series of 30 total hip replacements using a hydroxyapati te (HA)-coated, modular implant (Omnifit) was followed clinically and by roentgen stereophotogrammetric analysis for two years and compared with two control groups, one of 27 cemented Charnley sockets and one o f 40 cemented Charnley stems, Omnifit sockets with a central gap betwe en the dome of the socket and the acetabular bone in the postoperative radiographs, migrated less than sockets without such gaps (p=0.01). A fter adjustment for patient-related factors (age, gender and weight), no significant difference was found between the two prostheses with re spect to micromotion and wear, We conclude that the early fixation of the HA-coated Omnifit prosthesis compares with that of the cemented Ch arnley prosthesis.