Preliminary clinical research on epiphyseal distraction in osteosarcoma in children

BACKGROUND The feasibility of distal femur epiphysis preservation through epiphyseal distraction by external fixator in childhood osteosarcoma was explored. METHODS Between July 2007 and May 2011, 10 children who were suffering from distal femur osteosarcoma received epiphyseal distraction by external fixator, combined with tumor resection and repair with massive allograft bone to preserve the epiphysis of the distal femur and knee function. There were six male and four female patients, 9- to 14-years old (average 10.5 years old). The tumors were staged clinically according to the Enneking staging method: six cases were classified as stage in IIA and four cases as stage in IIB. All patients were diagnosed by biopsy, then received chemotherapy before and after surgery. All patients received tumor bone resection and the defects of the bone were repaired with massive allograft bone that was fixed by intramedullary nails; the distracted epiphysis and allograft bone were fixed with cancellous screws. RESULTS All cases received follow-up from 15 to 56 months (average 38.5 months). There were no local recurrences. One case died of lung metastasis and one case had poor incision healing for rejection of allograft bone. According to the functional evaluation criteria of the International Society of Limb Salvage (ISOLS) after operation, five cases were rated excellent, four cases good and one case fair. The ratio of excellent or good was 90.0%. There was no statistically significant difference in length between the operated and the normal lower limbs during the last review. CONCLUSIONS Epiphyseal distraction by external fixator can result in satisfactory limb length and joint function for children with a malignant bone tumor.