Abstract
Abstract We have prospectively analysed a single-surgeon series of 35 consecutive revision THRs with AAOS bone loss grade II–III, requiring morcelised allograft (ethylene oxide sterilised) for acetabular defects. Patients have been followed up for a minimum of 5 years. Although the results are encouraging, we are observing migration patterns in some cases.
Method Twenty-one patients were eligible for final analysis (follow-up for at least 5 years, range 5 to 10 years). Follow-up has consisted of clinical assessment (Charnley activity, pain, function, satisfaction) and a radiographic assessment (AP X-ray) of the replacement hip. Our study end-points are 1) prosthesis revision and, 2) acetabular cup migration at last follow-up.
Results There were 6 deaths with less than 5 years follow-up (unrelated causes) and 2 cases have been lost to subsequent follow-up. Two cases had deep infection (revised to a girdlestones procedure at 9 months and 2 years respectively) and there were no early dislocations. One case underwent further revision at 4 years follow-up due to symptomatic (superior) cup migration and three cases are awaiting imminent out-patient assessment. Twenty-one cases have had a mean follow-up of 5.83 years. Eight cases (23%) have shown no cup migration. Five have shown only late stage migration, 4 cases have shown both initial and then late migration whilst 3 cases have shown only intermediate migration followed by stability. One case has shown progressive migration throughout follow-up. All 13 cases (37%) exhibiting migration are still asymptomatic.
Conclusion Our results show that use of morcelised acetabular allograft for revision hip surgery with deficient medial and superior acetabular wall is a useful surgical procedure. Our results over a minimum of 5 years follow-up are comparable to others in this field. However, the relatively high number of revision cases from our data which have shown, as yet, asymptomatic cup migration causes concern for future management of these patients. It is imperative that all such cases have regular (annual) indefinite follow-up. We are concerned that further cases may present with acetabular cup migration in view of our results.
Theses abstracts were prepared by Mr Peter Kay. Correspondence should be address to him at The Hip Centre, Wrightington Hospital, Appley Bridge, Wigan, Lancashire WN6 9EP.
