Fibula flap in upper extremity segmental/critical size bone defects fixed with locking plates. Single-institution observational cohort.

INTRODUCTION: Management of bone defects in the upper extremity can vary depending on the size and location of the defect. Large defects may require complex reconstruction techniques. Vascularized bone grafts, mainly free vascularized fibula flap (FVFF), have many advantages in the treatment of bone or osteocutaneous defects. However, complications such as graft fracture are the most common, with a free fibula flap for bone defects in the upper extremity. This study aimed to describe the results and complications associated with the treatment of posttraumatic bone defects in the upper extremity using FVFF. We hypothesized that performing osteosynthesis using locking plates would prevent or reduce the fracture of the fibula flap MATERIALS AND METHODS: This was a retrospective single-centre cohort study. Patients with segmental bone defects caused by trauma who underwent reconstructive surgery with FVFF fixed with locking compression plates (LCP) between January 2014 and 2022 were included. Demographic variables and preoperative data, such as bone defect, location, and time until reconstruction, were collected. Bone defects were classified according to the Testworth classification. Intraoperative variables included the length of the FVFF, type of graft (osteocutaneous or not), type and technique of arterial and venous sutures, number of veins used as output flow, and the osteosynthesis technique used.

RESULTS: Ten patients were included (six humerus, three ulna, and one radius). All patients had critical-size bone defects, and nine patients had a history of infection. In 9 of 10 patients, bone fixation was performed with a bridge LCP and in one patient with two LCP plates. In eight cases, the FVFF was osteocutaneous. All the patients showed bone healing at the end of the follow-up period. There was one early complication, donor site wound dehiscence, and two long-term complications (proximal radioulnar synostosis and soft-tissue defect).

CONCLUSION: A high rate of bone union with a low rate of complications can be obtained with an FVFF in upper extremity segmental/critical-size bone defects. Rigid fixation with locking plates avoids stress fractures of the grafts, mainly in humeral reconstruction. However, in these cases, a bridge plate should be used.