Abstract
Introduction
Hydroxyapatite (HA) coated femoral stems require a press fit for initial stability prior to osteointegration occurring. However this technique can lead to perioperative femoral fracture.
Materials and Methods
506 consecutive patients under 72 years who underwent primary total hip replacements (THR) under 72 years were investigated for perioperative femoral fractures. All patients were independently assessed pre- and post-operatively in a research clinic. Assessment was made by Merle d'Aubigné and Postel (MDP) hip scores and radiographs. Between 1995 and 2001 patients were randomised to a partially HA coated, Osteonics Omnifit or fully HA coated Joint Replacement Instrumentation Furlong stem. Between 2001 and 2004 all patients received an Anatomique Benoist Girard (ABG II) stem partially coated. Fractures were identified from check radiographs and operative notes. The type of fracture was classified according to the modified Vancouver classification. The incidence of revision was also recorded.
Results
There were 38 fractures (7.5%) overall. The Omnifit group had 9 fractures (7.4%) the Furlong 11 (8.9%) and the ABG II 18 (6.7%). Twenty-four cases were treated by internal fixation at the time of primary surgery. Four cases had an unsatisfactory result and two were revised. Fourteen had conservative treatment. Seven of these had an unsatisfactory result and four required early revision. The difference between the operated and conservative treatment groups was significant (P<0.01). There was a correlation between Vancouver classification and outcome.
Conclusion
Perioperative fracture is relatively common. The type of fracture has an influence on the outcome. Unstable fracture patterns require internal fixation at the time of initial surgery.
