【Abstract】 Objective To evaluate the outcome of two-stage revision for prostheses infection in patients with bone tumor after knee prosthetic replacement. Methods Between August 2003 and August 2010, 22 patients with prostheses infection, who underwent knee prosthetic replacement in limb salvage treatment because of bone tumor, received two-stage revision. There were 11 males and 11 females with an average age of 29.6 years (range, 15-55 years). Prosthetic infection occurred after primary replacement in 20 patients and after revision surgery in 2 patients from 15 days to 89 months after operation. According to Coventry and Fitzgerald classification, type I was found in 3 cases, type II in 15 cases, and type III in 4 cases. The time from infection to admission was 5-47 months (mean, 10.2 months). The results of bacterial culture were positive in 9 cases and negative in 13 cases. Two patients had fever and leukocytosis. In one-stage, the implants and infected tissue were removed, and an antibiotic cement spacer with an intramedullary nail was implanted. In two-stage, a new endoprosthesis was inserted after infection was controlled. Results The C-reactive protein and erythrocyte sedimentation rate before one-stage debridement were significantly higher than those before two-stage revision (P lt; 0.05). All patients were followed up 5-63 months (mean, 23.6 months). Infection was controlled after one-stage debridement in 18 cases (81.8%); two-stage revision was performed in 17 cases, and 1 case refused to receive two-stage revision. Of 17 patients, 1 patient was amputated because of infection at 5 months after revision. Four patients (18.2%) underwent amputation because of failure to control infection after one-stage debridement. The limb salvage rate was 77.3% (17/22). One case of renal cell carcinoma with bone metastasis died of original disease after 1 year and 6 months of operation. The Musculoskeletal Tumor Society (MSTS 93) score was 69.4 ± 12.7 at last follow-up. Conclusion Two-stage revision should be performed in time and it has good results in the treatment of prostheses infection in patients with bone sarcomas after knee prosthetic replacement.
Objective To identify the postoperative function and short-term outcome of Global Modular Replacement System (GMRS) for reconstruction of defect after removal of tumor so as to supply information for cl inical appl ication. Methods Between March 2007 and May 2009, 30 l imb-salvage cases reconstructed with GMRS were retrospectively reviewed, including 18 males and 12 females with a median age of 25 years (range, 11-57 years). The preoperative diagnoses were osteosarcoma in 15 cases, mal ignant fibro-histiocytoma in 4, giant cell tumor in 3, chondrosarcoma in 2, and Ewing’s sarcoma and angiosarcoma in 1 respectively. The duration of symptom ranged from 1 to 15 months with an average of 5.6 months. There were 4 revision cases at mean time of 3.4 years after index surgeries. The locations were the proximal femur in 3 cases, distal femur in 22 cases, and proximal tibia in 5 cases. According to Enneking stage, 2 cases were rated as stage IB, 1 as stage IIA, and 27 as stage IIB. Four cases were compl icated by pathologic fracture. Results The average operation time was 165 minutes (range, 120-240 minutes); the mean blood loss was 448.3 mL (range, 100-1 500 mL); and the mean resection length was 14.1 cm (range, 7.5-22.5 cm). All the wounds healed by first intention. All 30 patients were followed up 10-35 months (22.3 months on average). Local recurrence occurred in 2 cases (6.7%) at 5 and 14 months respectively and distal metastasis occurred in 5 cases (16.7%) at 4-12 months (7.3 months on average) postoperatively. One patient died of multiple lung metastases at 10 months postoperatively. Twenty-nine patients survived at last follow-up, including 25 cases of tumor-free survival and 4 cases of tumor bearing survival. Aseptic loosening occurred in 2 cases (6.7%) at 1.5 years and 2 years postoperatively respectively. Deep infection occurred in 1 case (3.3%) at 1 year postoperatively. At last follow-up, the Musculoskeletal Tumor Society (MSTS) 93 scores were 4.6% ± 0.7% for pain, 3.7% ± 0.9% for function, 3.2% ± 1.3% for satisfactory degree, 4.3% ± 0.9% for orthesis, 3.7% ± 0.7% for walking, 3.3% ± 1.0% for gait; total score was 75.9% ± 14.2%. The Toronto Extremity Salvage Score (TESS) score was 87.0 ± 7.0. Conclusion Reconstruction for defect after removal of tumor with GMRS has satisfactory short-term outcome with good function recovery and low compl ication rate.