Onlay vascularized fibular grafting as a salvage procedure for the management of nonunion after reconstruction of the femur following tumor resection.

Purpose: The femur is prone to nonunion after biologic reconstruction following tumor resection, due to high bending forces. Nonunion at the host-graft junction is difficult to treat since the graft is in an avascular state. We aimed to investigate the clinical and radiographic results of an onlay free vascularized fibular grafting (VFG) as a salvage procedure for nonunion management after biologic reconstruction of the femur following bone tumor resection.

Methods: We retrospectively reviewed 10 patients (8 men and 2 women, median age: 15.5 years, range: 10-47) who underwent an onlay VFG for nonunion after intercalary reconstruction of the femur using an allograft ( n = 7) or pasteurized autograft ( n = 3), following tumor resection. The median follow-up period after VFG was 85.7 (24.6-163.5) months.

Results: The median time to union between the host bone and the VFG osteotomy sites was 3.5 (2.8-4.5) months. The median time to union at the host-graft junctions was 10.6 (6.6-12.7) months. Two postoperative complications requiring revision surgery occurred in two patients: one graft fracture and one deep infection with synchronous graft fracture. Internal fixation was required in the patient with graft fracture. The patient with the infection and synchronous graft fracture was treated using debridement, antibiotics, and an external fixator. The median Musculoskeletal Tumor Society functional score was 88% (60-97%) at the final follow-up.

Conclusion: Onlay VFG as a salvage procedure for nonunion of a biologic intercalary reconstruction of the femur after tumor resection is a useful treatment option.