Background: There have been few reports on the mid- and long-term follow-up results of the proximally HA-coated femoral stem. We evaluated this type of stem prospectively, with 6-12 years of follow-up.
Methods: The survival rate, Harris hip score and radiographic features of 106 hips in 100 consecutive patients were evaluated. The mean age at operation was 51 years (SD 8.2).
Results: The mean Harris hip score at the time of the latest follow-up was 95 points. Spot welds occurred in 95% of the patients and were first observed at a mean follow-up of 1.4 years in one or more of the Gruen regions, corresponding to the coated part of the femoral stem. A higher grade of stress shielding correlated with a less favorable Harris hip score and pain subscore. According to the criteria of Engh, all stems were graded as stable and durable bone-ingrown. No femoral component was revised.
Interpretation: At an average follow-up of 8 years, this proximally HA-coated femoral component showed favorable clinical and radiological outcome and excellent survivorship.