Functional Neuro-Vascularized Muscle Transfer for Oncological Reconstruction of Extremity Sarcoma

Introduction: Functional neuro-vascularized muscle transfer (FMT) is a beneficial tool for restoring joint movement involving the reconstruction of “movement” in the affected extremity. Until now, however, the clinical application of FMT was mainly limited to trauma cases and to date, very few studies have focused on musculoskeletal oncology. In this study, we reviewed patients who underwent wide resection for extremity sarcoma and functional reconstruction using FMT and discussed the advantages, indications and complications of the procedure.

Methodology and Material: We reviewed 28 patients who underwent wide resection and subsequent reconstruction by FMT. The patients comprised 16 males and 12 females and their mean age was 48 years (range 9-70). All patients had high grade sarcoma. Reconstructed muscles were the quadriceps femoris muscle in 14 patients, hamstring in 3, triceps brachii (pedicled transfer) and tibialis anterior in 3, finger flexor in 2 and finger extensor and triceps surae in 1. Latissimus dorsi muscle was transferred in 23 patients and gracilis muscle was in 5. After tightly attaching both stumps of the muscle, microsurgical anastomosis of the vessels was performed. Finally, nerve repair was performed as close as possible to the muscle to decrease the denervation period.

Results: Three patients (11%) died of metastatic disease and local recurrence occurred in three. One case developed venous thrombus immediately after surgery and was rescued by re-anastomosis of the vein. Postoperative infection was not observed at the donor and recipient site. 27 (96%) transferred muscles showed evidence of re-innervation electrophysiologically between 4 to 7 months after surgery. Muscle power was improved to an MMT score of 2 in average after re-innervation of the transferred muscle. This increase in MMT resulted in a meaningful QOL improvement.

Conclusions: Conventional myocutaneous flap transfer (non-neurotized) is a beneficial tool for achieving stable wound closure and successful soft tissue coverage in one step, prevention of lymphedema, thus decreasing the infection rate. Besides these advantages, neuro-vascularized functioning muscle transfer achieves the additional benefit of restoring joint movement. The selected donor muscle should have the properties of 1) adequate strength, 2) a suitable range of motion, and 3) an adaptable shape for the recipient area.