[Application of rotationplasty in treatment of osteosarcoma of distal femur in children].

OBJECTIVE

To investigate the effectiveness of rotationplasty in treating osteosarcoma of distal femur in children.

METHODS

A clinical data of 10 children with osteosarcoma of distal femur treated with rotationplasty between March 2014 and June 2016 was retrospectively analyzed. There were 7 boys and 3 girls with an average age of 6.7 years (range, 4-10 years). There were 4 cases of osteoblastic osteosarcoma, 4 cases of mixed osteosarcoma, and 2 cases of chondroblastic osteosarcoma. All children were staged as Enneking stage ⅡB. The disease duration ranged from 3.5 to 6.0 months (mean, 4.6 months). The lower limb functional scoring system of 1993 Musculoskeletal Tumor Society (MSTS93), Toronto Extremity Salvage Score (TESS), and knee mobility were used to evaluate postoperative function. Tumor recurrence and metastases were monitored by radiograph.

RESULTS

Poor superficial incision healing occurred in 1 patient, and healed after dressing change. The other incisions healed by first intention. All children were followed up 24-72 months (mean, 52.6 months). No local recurrence was observed during follow-up. Three of the ten patients suffered from metastases including 1 dying of multiple organ dysfunction syndrome, 1 alive with tumor, and 1 tumor free survival. Painful callosities and ulcers which related to prosthetic wear occurred in 2 patients and turned up after optimizing prosthetic fit and physiotherapy. The fracture healing time was 2.5-5.0 months (mean, 3.5 months). All children could walk independently at 4 months postoperatively. At last follow-up, the MSTS93 score was 19-25 (mean, 22) and the TESS score was 87-93 (mean, 90). The extension of knee joint mobility with artificial limbs was 0°-10° (mean, 5°), and the flexion of knee joint mobility with artificial limbs was 85°-95° (mean, 90.5°).

CONCLUSION

Rotationplasty in treating osteosarcoma of distal femur in children with limb salvage difficulties can effectively preserve the limb function and improve the quality of life, and it can be used as an alternative to amputation.