Abstract
Introduction
The treatment osteonecrosis of the femoral head remains uncertain. Core decompression is the standard technique for the early stages (ARCO I and II). A new alternative is core decompression combined with the insertion of an osteonecrosis rod. This implant is supposed to reduce the intraosseous pressure and to give additional structural support. The aim of this study was to evaluate the clinical and radiological outcome via magnetic resonance imaging (MRI) of this new technique.
Methods
Twenty-three patients were included in this study. All patients underwent a core decompression combined with the insertion of an osteonecrosis rod.
Results
A survival rate of 44 % (10 of 23 patients) was found. The conversion to a total hip arthroplasty was performed after a mean interval of 529 days (range, 120 to 1348 days) because of persistence of pain or destruction of the joint. In five cases, a conversion to a long-stem hip arthroplasty, in seven cases to a short-stem arthroplasty, and in one case in an external hospital, to a hip resurfacing was performed. The majority of patients within the surviving group revealed an almost unchanged stage (mean follow-up of 477 days). In two cases, a radiological regression was obvious. A follow-up MRI of one of those patients showed complete regression.
Conclusion
The outcome after core decompression combined with the insertion of a tantalum osteonecrosis intervention implant did not show superior results compared to core decompression. This is in contrast to prior studies. In addition, the surgical procedure and rehabilitation was prolonged and the costs higher than for isolated core decompression. An advantage is low risk of fracture post-operatively. In the case of conversion to total hip arthroplasty, no problems appeared during explantation of the tantalum implant.
