Gracilis free tissue transfer
In patients who have long-term flaccid facial palsy (generally
longer than 2 years), the native facial muscles are no longer
functional as they have not had nerve input for a prolonged period
of time. At the Facial Nerve Center, we often take a small piece of
muscle from the inner thigh, the gracilis muscle, and transplant it
to the face to replace the muscles which make patients smile. When we transplant the gracilis muscle to the face to recreate the smile, we connect it to blood vessels to nourish the muscle, and to a nerve to innervate the muscle to restore smiling movement. There are no side effects of borrowing a small piece of gracilis muscle from the inner thigh to help patients smile again.
The gracilis free tissue transfer (aka gracilis free flap) is performed under general anesthesia. During the procedure, the surgeon will make a facelift incision on the affected side that extends into the neck below the jaw bone in a natural skin crease. Through this incision, the surgeon identifies blood vessels in the face which will supply the gracilis muscle once it is transplanted to the face. He or she will also lift the fat and skin of the cheek so that the gracilis muscle can sit in the proper plane and vector to help patients smile again. While this is being performed, another surgeon will make a small incision along the upper inner thigh and harvest the small piece of gracilis muscle along with its blood vessels and nerve. Ordinarily, two facial nerve surgeons work together at the same time during the procedure to minimize the amount of time patients are under general anesthesia. Once the muscle is harvested and the face prepared, we sew the muscle to the upper lip on the affected side, and hook it up to blood vessels in the face and to the nerve which will innervate the muscle.
The surgeon and patient decide together which nerve will drive the gracilis muscle. The options include the contralateral smile branches of the facial nerve, usually using a nerve graft connected to one or two branches of the facial nerve on patients’ healthy side (see cross facial nerve graft section), and/or a branch of the masseteric nerve, one of the chewing nerves. While using a nerve graft connected to the healthy facial nerve allows for the possibility of a spontaneous smile, it is not as reliable as when the operation is perfomed using the masseteric nerve. However, using the masseteric nerve usually menas that people have to think to bite down or clench slightly to smile, particularly when they first start seeing movement. At the Facial Nerve Center we spend a great deal of time helping patients decide what procedure is best for them.
A. The zygomaticus major smile is the most common (67%). (Rubin LR. Expression of emotions: the role of nasolabial fold and the anatomy of the smile. In: Rubin LR, ed. The paralyzed face. St. Louis: Mosby-Year Book, 1991; 11-15.) It is produced by a dominant zygomaticus major muscle and the buccinator (green) that results in the corners of the mouth being elevated first. B. The canine smile is the next most common (31%) smile and results from a codominant levator labii superioris, which contracts first upon initiation of a smile followed by activation of the zygomaticus major and buccinator for elevation of the corners of the mouth. C. The full denture smile is the least common (2%) smile. It results from full activation of elevators and depressors of the lips and angles of the mouth, thus displaying both maxillary and mandibular teeth.
After a gracilis free tissue transfer procedure, patients usually stay in the hospital for two days and go home the third day after surgery. Patients have a drain in the thigh and face, both which are removed prior to discharge home. Patients will have some discomfort in their leg and face as well as swelling in their face, both which peak around 2-3 days after surgery. Patients are able to walk around the day after surgery. There are sutures in the face incision that will need to be removed 1-2 weeks after surgery (either here or with a local surgeon, for patients who travel from a distance for this surgery). Depending on the nerve which is used to innervate the gracilis muscle, patients may start to see movement from the muscle 5-12 months after surgery, at which time we have them work with our physical therapists to learn how to optimally use their new smile muscle.