[Bipolar prosthetic replacement for proximal femoral tumors].

Objective: To evaluate the effectiveness of bipolar prosthetic replacement for proximal femoral tumors from the perspectives of patient survival, prosthesis survival, functional outcomes, and complication rates.
Methods: Between July 2001 and July 2010, 96 patients with proximal femoral tumors underwent wide resection and bipolar prosthetic replacement, including 83 cases of primary femoral tumors and 13 cases of soft tissue sarcomas involving the proximal femur. There were 50 male and 46 female patients with a mean age of 43.2 years (range, 15-69 years). Prosthetic replacement for proximal femoral tumors was used in 85 patients and deactivated bone-prosthetic complex was used in 11 patients. According to Enneking staging, the patients were divided into 3 groups: group A, 24 patients at stages IA, IB, and benign lesion; group B, 56 patients at stages IIA and IIB; and group C, 16 patients at stage III, myeloma, and lymphoma. The American Musculoskeletal Tumor Society 1993 version (MSTS93) functional score was used to evaluate the lower limb function.
Results: Primary healing of incision was obtained in 93 patients; 3 patients had poor healing, which was cured after debridement. Of the patients, 89 were followed up 6.5 years on average (range, 1-10 years). During follow-up, 28 patients died of tumor. The 5- and 10-year survival rates of patients were 100% in group A, and were 56.5% and 41.5% in group B respectively, and the 5-year survival rate was 18.4% in group C; there was significant difference among 3 groups (P < 0.01). The 5- and 10-year survival rates of prosthesis were 74.4% and 62.5%, which were significantly higher than those of patients in groups B and C (P < 0.01). Sixty-one patients were followed up 1-10 years (mean, 4.7 years) for functional evaluation. The mean MSTS93 score of the survival patients was 79% (range, 63%-95%) at last follow-up. Complications were observed in 15 patients (16.9%): hip dislocation in 2, delayed infection in 2, aseptic loosening in 8, severe acetabulum wear in 1, and hip pain in 2.
Conclusion: Bipolar proximal femoral prosthetic replacement for proximal femoral tumors can provide a satisfactory functional outcome, especially for tumors at stage II or III and myeloma and lymphorma patients. Revision is needed because of main late complications of aseptic loosening, hip pain, and acetabulum wear.