Reconstruction of lower limb defect with a variant sural neuro-fasciocutaneous flap: A case report.

Introduction: The sural neuro-fasciocutaneous flap is widely used for reconstructing skin defects in the lower calf. Variations of the sural nerve in the calf are infrequent, which may require a variation in the traditional surgical procedure.

Case Presentation: A 76-year-old male patient had soft tissue defect of the right lateral ankle and lower leg caused by an accident 18 years ago. He had exposed bones and had osteomyelitis. He underwent two primary operations, and finally, we used a sural neuro-fasciocutaneous flap to effectively cover the defect. We observed that the course of the sural nerve was atypical during the surgery, and we adjusted the flap axis laterally to bring the lateral sural cutaneous nerve inside the flap to improve the success rate of the surgery. The flap entirely survived, and there was no sensory impairment in the calf. The patient was discharged from the hospital after 10 days.

Clinical Discussion: Some type of variant of the sural nerve makes the flap harvest without the neurovascular component of the sural nerve and the cutaneous chain, which might decrease flap survival. Moving the flap axis laterally and bringing in the lateral sural nerve or peroneal communicating nerve offers an adequate blood supply to the vascular territory and the flap region.

Conclusion: In patients with sural nerve variants, the procedure does not have to follow the traditional theory of the sural neuro-fasciocutaneous flap. Preoperative and intraoperative protection of the sural nerve variant should also be considered.