Background: Metal on metal resurfacing of the hip is an attractive conservative treatment option for the younger, active arthritic patient. It has the advantages of bone preservation and the longevity of metal bearing surfaces. Concerns remain over the performance of these implants due to historical failure of similar devices. The possible longer-term survival of these implants can only be justified if the early results are as successful as conventional hip replacement.
Patients &
Methods: The clinical and radiological follow-up of our first 25 consecutive resurfacing patients is presented. The Birmingham Hip Resurfacing prosthesis (Midland Medical Technologies, Birmingham, UK) was used, and all procedures performed by the senior author (EHM). Clinical assessment was done using the modified Harris Hip Score, and functional outcomes measured using the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC). Radiographs were examined for radioleucent lines, migration of components, osteolysis and heterotropic ossification.
Results: 28 primary hip resurfacings in 25 patients were reviewed. The mean follow up period was 18 mts (12– 36mts). The mean age of patients at time of operation was 51yrs (37–64 yrs). Main indication for surgery was Osteoarthrosis. The mean Harris Hip Score improved from 44 preoperative, to 94.5 postoperative. The mean preoperative WOMAC score was 30 and the mean postoperative score 88.The average duration of hospital stay was 5 days, and the average operative blood loss 3g %. All patients in paid employment returned to work at an average of 8 weeks postoperatively, and majority of patients are able to participate in sports and recreational activities. There were no cases of dislocations, femoral neck fractures, avascular necrosis or osteolysis.
Conclusion: Hip resurfacing using metal on metal hybrid fixed components, offers a viable treatment alternative in younger active patients. Early outcomes are at least comparable to total hip replacement in terms of pain relief and restoration of function.
Despite the lack of long-term data, the relative absence of complications and the potential benefits justify its continued use. We believe the future is very promising for this procedure.
