Abstract
Purpose: Periprosthetic fractures around hip prostheses are difficult problems because these fractures range from the very simple (requiring no surgical intervention) to the complex (requiring major surgery). This paper evaluates the primary stability and restoration of femoral bone stock following treatment of Vancouver type B-2 periprosthetic fracture of the femur using an extensively hydroxy-apatite coated revision stem implant.
Methods: We have prospectively reviewed 9 cases with B-2 periprosthetic fracture operated at our centre between 1996 to 2001. Of the nine patients, 4 were male and 5 female. The mean age was 76.7 years (50-92). All patients were treated by femoral revision using an extensively hydroxy-apatite coated titanium revision femoral stem (Restoration HA, Stryker, Rutherford, NJ). Fixation was augmented with a combination of cerclage cables and onlay cortical strut allografts.
Results: There has been no loss to follow-up. 1 patient died, but at most recent follow-up the fracture had united with radiological evidence of bone on-growth to the stem. Mean follow up in the rest of the cohort was 3.3 years. There was radiological evidence of fracture union in all patients. Mean subsidence of the stem was 0.22mm. At most recent follow-up the mean Harris Hip Score had improved to 77.2 (63-93). Favourable bone remodelling was observed in all patients with no evidence of stress shielding so far. At most recent follow-up there have been no cases of mechanical failure, deep infection or dislocations. No patient is awaiting further revision.
Conclusion and Significance: Te Restoration HA stem has produced excellent clinical results in our study. We have observed no intra operative fracture and low postoperative complication rate. We are extremely encouraged by the observed femoral remodelling. There has been no case of mechanical failure as yet and there is no reason to expect, once union and on-growth have occurred, that loosening will be a problem. In treating this challenging and increasingly common complication of total hip replacement, femoral revision using an extensively HA coated revision femoral component offers a reliable method of femoral fixation leading to successful fracture healing and early return to function.
Correspondence should be addressed to Mr Carlos Wigderowitz, Senior Lecturer, University Department of Orthopaedic and Trauma Surgery, Ninewells Hospital and Medical School, Dundee DD1 9SY.
