PROXIMAL FRACTURE OF THE FEMUR: USEFULNESS OF FIRST-LINE REVISION PROSTHESIS

Abstract

Purpose: Treating fractures of the femur in patients with a total hip arthroplasty is a difficult task. The frequency of these fractures is estimated at 1% to 3%. The purpose of this work was to evaluate the long-term clinical and radiological outcome and to search, by type of fracture, for factors predictive of late complications in order to improve indications.

Material and methods: Since 1985, we collected data on 29 patients (17 women and 12 men) mean age 73.3 years who had a fracture of the femur after total hip arthroplasty. By definition, intraoperative fractures were excluded. Two independent operators noted epidemiological, therapeutic and imaging data and classed the fractures using the Vancouver classification. Treatments used were noted and clinical and radiological outcomes at mean follow-up of 24 months (6–140) were analysed.

Results: Falls were the cause of the fractures in 31 patients (84%). Six of these patients had a revision prosthesis. Five fractures were in a zone of unprotected weakness. The fractures were trochanteric (n=9), periprosthetic (n=18), or below the stem (n=2). Nine patients were treated by isolated osteosynthesis and eleven by replacing the prosthesis. The Beals score was used to assess outcome taking into account the stability and the quality of the implant fixation as well as fracture realignment. In patients whose fracture was around the stem, outcome was excellent in two, good in one, and poor in four. For fractures of the lesser trochanter (n=4), outcome was excellent in two and good in two. For fractures below the stem (n=2), outcome was good in both. There was one case of deep infection.

Discussion: Considering the same types of fractures, orthopaedic treatments produced poor results (6/11), unlike prosthesis replacement (2/11) and osteosynthesis (1/9). The number of loosenings was underestimated, leading to failure of orthopaedic treatment.

Conclusion: In the event of fracture of the proximal femur in patients with a total hip arthroplasty, any suspected loosening, particularly of a cemented stem, should lead to prosthesis revision rather than orthopaedic treatment or simple osteosynthesis.