Background and Objectives: The placement of megaprostheses in patients with bone sarcoma is associated with high rates of infection, despite prophylactic antibiotic administration. In individual cases, secondary amputation is unavoidable in the effort to cure infection. Methods: The infection rate in 51 patients with sarcoma (proximal femur, n ¼ 22; proximal tibia, n ¼ 29) who underwent placement of a silver-coated megaprosthesis was assessed prospectively over a 5-year period, along with the treatment administered for infection. The infection rate was compared with the data for 74 patients in whom an uncoated titanium megaprosthesis (proximal femur, n ¼ 33; proximal tibia, n ¼ 41) was implanted. Results: The infection rate was substantially reduced from 17.6% in the titanium to 5.9% in the silver group. Whereas 38.5% of patients in the titanium group ultimately had to undergo amputation when periprosthetic infection developed, these mutilating surgical procedures were not necessary in the study group. Conclusions: The use of silver-coated prostheses reduced the infection rate in the medium term. In addition, less aggressive treatment of infection was possible in the group with silver-coated prostheses. Further studies with longer term follow-up periods and larger numbers of patients are warranted in order to confirm these encouraging results.

We evaluated the clinical results and complications after extra-articular resection of the distal femur and/or proximal tibia and reconstruction with a tumour endoprosthesis (MUTARS) in 59 patients (mean age 33 years (11 to 74)) with malignant bone or soft-tissue tumours. According to a Kaplan-Meier analysis, limb survival was 76% (95% confidence interval (CI) 64.1 to 88.5) after a mean follow-up of 4.7 years (one month to 17 years). Peri-prosthetic infection was the most common indication for subsequent amputation (eight patients). Survival of the prosthesis without revision was 48% (95% CI 34.8 to 62.0) at two years and 25% (95% CI 11.1 to 39.9) at five years post-operatively. Failure of the prosthesis was due to deep infection in 22 patients (37%), aseptic loosening in ten patients (17%), and peri-prosthetic fracture in six patients (10%). Wear of the bearings made a minor revision necessary in 12 patients (20%). The mean Musculoskeletal Tumor Society score was 23 (10 to 29). An extensor lag > 10° was noted in ten patients (17%). These results suggest that limb salvage after extra-articular resection with a tumour prosthesis can achieve good functional results in most patients, although the rates of complications and subsequent amputation are higher than in patients treated with intra-articular resection.

The use of silver-coated prosthesis reduced the infection rate in a relatively large and homogeneous group of patients. In addition, less-aggressive treatment of infection was possible in the group with silver-coated prosthesis.

These results suggest that limb salvage with tumour prostheses after intra-articular resection can achieve good functional results with an active extension of the knee in the majority of patients. While mechanical complications can be treated successfully with revision surgery, periprosthetic infection continues to be the main reason for secondary amputation.

Using a silver-coated proximal femoral replacement nearly halved the overall infection rate. When infections occurred, it was usually possible to avoid two-stage prosthesis exchanges in the silver group.