Accordion Maneuver for Delayed Regenerate Formation Following Pediatric Osteosarcoma Resection: A Case Report and Literature Review

Background and Clinical Significance: Reconstruction of large segmental bone defects following oncologic resection in pediatric patients remains a major challenge. Although distraction osteogenesis with bone transport is a well-established biological reconstructive option, regenerate formation may be compromised in patients receiving chemotherapy. The accordion maneuver, consisting of alternating cycles of compression and distraction, has been described as a method to stimulate bone regeneration, primarily in association with external fixation systems. However, its use in internal bone transport systems using intramedullary lengthening nails following oncologic resection, particularly in the setting of perioperative chemotherapy, remains rarely reported. Case Presentation: We report a case of a 12-year-old boy with high-grade telangiectatic osteosarcoma of the distal femur who underwent neoadjuvant chemotherapy followed by limb-salvage surgery, resulting in a 14 cm segmental bone defect. Reconstruction was performed using plate-assisted bone transport with a motorized intramedullary magnetic nail. During distraction osteogenesis, delayed and asymmetric regenerate formation developed. An accordion maneuver was subsequently initiated, resulting in progressive improvement in regenerate density and corticalization without the need for revision surgery. Conclusions: This case highlights the successful application of the accordion maneuver using internal bone transport following oncologic resection. It represents a minimally invasive technique to stimulate bone healing and may reduce the need for revision surgery; however, larger series are needed to confirm this potential benefit, particularly in biologically compromised patients receiving chemotherapy.