Unexpected early loosening was noted in some patients who had bipolar hemiarthroplasties using a specific combination of head and stem.
A review of all patients who had received this implant combination was performed to establish whether there was a higher than expected failure rate and to identify those patients who had evidence of early loosening requiring further intervention or monitoring.
Theatre records were reviewed to identify those who had undergone bipolar hemiarthroplasty using these products. All surviving patients were contacted and offered an appointment at which they underwent clinical and radiological review. Following review, revision rates were compared to published Australian joint registry data.
Of 247 eligible for recall, 139 attended for clinical and radiological review. The cumulative revision rate was 6.8 % at 4 years, with a mean time to revision of 26 months; however, there was a significantly higher revision rate of 12.1 % in those aged under 75 years at the time of surgery (p = 0.01). This is significantly higher than rates quoted for bipolar hemiarthroplasties in Australian joint registry data.
Overall, higher than expected revision rates due to early loosening were seen for this product combination, especially in patients aged < 75 years at the time of the initial surgery.