Abstract
Purpose: Prosthetic arthroplasty is the most common method of reconstruction of segmental bone defects following resection of bone sarcomas about the knee. The purpose of this study was to determine the survivorship of the reconstructions in short- and long-term follow-up.
Methods: A retrospective study was performed on all patients diagnosed with a bone sarcoma between 1984 and 1995 who were treated with a limb-sparing osteoarticular resection and rotating hinge prosthetic knee arthroplasty. Prosthetic survival was calculated with endpoints of analysis based on any event, any prosthesis-related event and aseptic loosening of the prosthesis, which led to prosthetic revision, removal or limb amputation.
Results: A total of 154 reconstructions were performed involving the distal femur (n=111) and proximal tibia (n=43). The median resection length was 155 mm (105–250mm) for the distal femur and 117 mm (85–150 mm) for the proximal tibia. All implants were fixed with polymethylmethacrylate cement. Early complications (within one year postoperatively) developed in fewer than 2 % of patients. Aseptic loosening accounted for the majority of events resulting in prosthetic failures (distal femur = 17 [median failure 34 mos]; proximal tibia = 10 [median failure 100 mos]). Polyethylene bushing wear was observed in seven patients (median time to replacement = 156 months).
Conclusion: The early outcome of prosthetic arthroplasty was extremely favorable supporting this method of reconstruction following excision of high-grade bone sarcomas about the knee. Long-term survival of these prostheses is suboptimal and can be anticipated to be poor for the proximal tibia. Aseptic loosening continues to be the primary cause of prosthetic failure about the knee.
The abstracts were prepared by Nico Verdonschot. Correspondence should be addressed to him at Orthopaedic Research Laboratory, University Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
