Noninvasive Expandable Endoprostheses From Reconstruction to Skeletal Maturity: A Surgical Technique and Lengthening Guide

Limb salvage is the benchmark for pediatric extremity bone sarcomas. However, reconstructive strategies must account for any anticipated remaining growth potential and the resultant limb inequality. Expandable endoprostheses offer the theoretical advantage of immediate weight-bearing, predictable function, and reliable maintenance of leg-length equality. The evolution of the lengthening mechanism now permits noninvasive lengthening, opposed to the multiple open procedures of the past. These design improvements have contributed to their growing popularity. Experience has indicated that these noninvasive implants more reliably achieve leg-length equality, have longer failure-free survival, and decreased complications, although some have noted gearbox and lengthening failures. Currently, no standardize technique exists for managing patients with noninvasive expandable implants from the time of reconstruction to final lengthening at skeletal maturity. This blueprint aims to provide a detailed surgical technique, lengthening schedule, and recommendations for the mitigation and management of complications to achieve successful limb salvage with noninvasive expandable endoprostheses.