Combining Shelf Osteotomy With Proximal Femoral Reconstruction After Oncologic Resection

Introduction: Oncologic proximal femoral resection and reconstruction in skeletally immature children remains a formidable task due to the risk of developing hip instability with patient growth or interval leg lengthening through the prosthesis. Shelf pelvic osteotomy increases femoral head coverage and containment, and favorable long-term results have been reported in the setting of developmental dysplasia of the hip and Perthes disease. We present a technique of combining shelf osteotomy with expandable proximal femoral endoprosthesis reconstruction in pediatric limb-sparing surgery. Materials and Methods: Four surgeons at 2 centers from 2012 to 2020 performed proximal femoral reconstruction with shelf osteotomy. Data were collected retrospectively on operative technique, radiographic measurements, and complications including dislocation, subluxation, implant loosening, pain, function, and radiographic outcomes. Results: Five patients were included in the study. The mean follow-up was 49 months (range: 17 to 104 mo). The mean lateral center edge angle status postproximal femoral resection and reconstruction shelf osteotomy was 56.1 degrees (±30.5). There were no reported incidences of subluxations, dislocations, periprosthetic fractures, or soft tissue complications. The 3 patients with the longest follow-up at 3, 5, and 8 years tolerated serial lengthening of the endoprosthesis totaling 1 cm, 7.25 cm, and 9 cm, respectively, and demonstrated earlier triradiate cartilage closure in the operative side compared with the nonoperative side. All patients have returned to independent ambulation. Discussion: Combining proximal femoral reconstruction with shelf osteotomy in limb salvage pediatric orthopedic oncology may help to improve hip stability with serial lengthening and patient growth.