Resurfaced allograft-prosthetic composite for proximal tibial reconstruction in children: intermediate-term results of an original technique

Background: Reconstruction of the proximal part of the tibia in children with megaprostheses or standard composite devices removes the distal femoral physis, and osteoarticular allografts have a high incidence of mechanical failure. We evaluated the results of an alternative original technique for proximal tibial reconstruction after tumor resection.

Methods: Nineteen children, ranging in age from six to sixteen years, who underwent surgical resection and reconstruction with a resurfaced allograft-prosthetic composite were retrospectively reviewed at a mean follow-up time of seventy-eight months. Eighteen children had high-grade sarcoma (fourteen had osteosarcoma and four had Ewing sarcoma), and one child had an aggressive giant cell tumor of the proximal part of the tibia. Surgical resection and its complications, disease-free survival of the patients, implant survival, and functional results according to the Musculoskeletal Tumor Society scoring system were analyzed at the time of the latest follow-up.

Results: In all patients, wide surgical margins were obtained and no local recurrence was observed. At the time of the latest follow-up, nine of the eighteen patients with a high-grade malignant tumor were continually disease-free, another six had had metastases but had no evidence of disease, and three had died of the disease. The patient with a giant cell tumor was continually disease-free after 168 months. The mean implant survival was sixty-eight months (range, six to 188 months). The major complications were one deep infection; two nonunions, which healed after surgical revision; and six allograft fractures. Limb-length discrepancy was the most frequent complication but, following contralateral epiphysiodesis, resulted in a mean discrepancy of 1.9 cm at the time of the latest follow-up. At the time of the latest follow-up, eight patients had a Musculoskeletal Tumor Society score deemed as excellent or good.

Conclusions: In children and young teenagers with bone tumors of the proximal part of the tibia requiring an intra-articular resection, knee reconstruction with a resurfaced allograft-prosthetic composite may represent a valid alternative to conventional megaprostheses or to osteoarticular allograft.