Innervated free flaps for foot reconstruction: a review

Whether to provide a sensate plantar weight-bearing flap to reconstruct the foot remains an unanswered, but frequently asked, question. It has been more than a decade since Graham and Dellon reviewed this subject. Increasing emphasis on outcome analysis of microsurgical reconstruction has prompted this new review. All published peer-reviewed literature related to reconstruction of the plantar surface of the foot was reviewed to identify whether the flaps were 1) local, regional or distant; 2) innervated or non-innervated and, if innervated, then 3) identified as to the donor and the recipient peripheral nerves. Outcome measures included direct measurement of sensibility, development of ulceration, and activities of daily living. It was concluded that it is still not possible to determine that innervated flap reconstruction of the weight-bearing portion of the foot is critical for either durability or ambulation. It is recommended that the original nerves that innervate the flap be blocked prior to harvest to improve flap design, i.e., that the flap actually contains the intended nerve. It is recommended that appropriate donor nerves are selected to innervate the flaps, e.g., the calcaneal nerve should be used to reinnervate heel reconstructions (rather than the sural nerve), and medial/lateral plantar branches be used to reinnervate the arch and the forefoot. Reinnervating a muscle flap with a sensory nerve will permit reinnervation of the muscle and the overlying skin, but whether this provides a superior result in durability and gait remains to be seen.