What is gracilis free flap surgery?
Gracilis free flap or gracilis free tissue transfer is a muscle transplant surgery, where a muscle from the inner thigh called gracilis is used to substitute paralyzed or missing smile muscles. Using a gracilis muscle leaves a scar in the inner thigh. Borrowing the muscle does not affect leg function long term, because there are multiple muscles in the inner thigh responsible for a similar function. Therefore, gracilis is currently the most popular free flap choice for facial paralysis reanimation due to a very favorable donor site, hidden scar and pliability of the muscle to shaped into smile muscles.
Once gracilis muscle is taken from the inner thigh, it is shaped into smile muscles prior to transplantation into the face. The shape and smile vectors are customized to each patient. In order to survive, transplanted muscles’ blood supply has to be re-established once it was transferred a long distance from the thigh to the face. In order to do that, the muscle is harvested with its own artery, vein and nerve.
Gracilis is harvested with its nerve called obturator nerve, so it can be powered by either patient’s native facial nerve or various nerve transplants. Connecting the obturator nerve to the nerves in the face lets patients use it as a smile muscle. It is commonly connected to a cross-face nerve graft or a combination of cross-face nerve graft and nerve to masseter. Similarly, the vessels between the gracilis free flap and the arteries and veins in the neck are connected under a microscope in order to establish blood flow to the transplant and therefore keep the muscle alive.
The gracilis muscle is monitored in hospital for 7-14 days after surgery to make sure the reconnected blood vessels maintain blood flow. Patients regain movement in 8-12 months after gracilis free flap surgery, because the transplanted nerves need time to regrow. Our expert facial physiotherapists train the gracilis transplant once it begins to move, therefore helping patients strengthen their smile.
When do I need gracilis free flap surgery?
Patients with flaccid facial paralysis for more than 2 years may no longer have functional facial muscles, because the muscles waste away if they are not used. In rare cases, patient’s smile muscles may be removed during cancer surgery. In those circumstances, patients do need both a nerve transplant and a gracilis free flap in order to achieve most natural movement on the paralyzed side.
Usually nerve transplant or cross-face graft surgery is performed first, allowing 6-12 months for the nerves to grow across the face. Your surgeon will test the readiness of the nerve for muscle transplant by tapping on the skin in a location where it was placed, which is called the “Tineal sign”. Tapping the nerve will produce pins and needles sensation signalling that the nerve cells have grown to the tapped end.
As a second stage surgery, the gracilis free flap is brought from the inner thigh and shaped into a smile muscles (called double paddle gracilis) in order to simulate the most natural smile. Gracilis free flap essentially replaces wasted smile muscles due to long standing flaccid facial paralysis. A free flap means that the muscle is brought up with its own artery, vein and nerve like a transplant. It is then connected to the cross-face nerve graft performed 6-12 month prior and the arteries and veins in the neck under a microscope. The muscle transplant then slowly learns movement from the nerve transplant over additional 8-12 months
How do I prepare for gracilis free flap surgery?
Prior to gracilis free flap surgery, your surgeon may get an electromyography (EMG) study of your facial muscles to determine if you are a candidate for the gracilis free flap or if nerve transplant alone would be sufficient.
What happens during gracilis free flap surgery?
Patients are taken in to the operating room and surgery is performed under general anesthesia. Facial nerve monitoring system to carefully monitor the facial nerve to ensure its integrity. This system is able to monitor the transplanted nerves and it can also help in obturator nerve identification in the inner thigh.
The incision is made in natural facial grooves, similar to a facelift incision, but it continues into the neck in a natural skin crease. Extension into the neck is necessary in gracilis free flap surgery because the muscle vessels are connected to neck vessels in order to ensure the transplanted muscle stays alive. Face is prepared for muscle transplant and skin is lifted all the way to the corner of the mouth. Preoperative photos and videos are used in the operating room in as a guide for smile creation. Function of the normal side of the face determines how the surgeon insets the gracilis muscle. Sutures are placed in the corner of the mouth and customized till the surgeon gets the smile just right according to preoperative photos and videos. The neck vessels are identified and prepared for the transplant under the microscope.
The leg is also sterilely prepared and an incision is made in the inner thigh similar to a thigh lift surgery. The gracilis muscle is identified along with its artery, vein and the obturator nerve. Two thirds of the muscle are usually taken for smile muscle creation. The muscle is shaped into two strips (double paddle) connected by arteries, veins and nerves. The two strips allow for the most natural smile creation. Each end of the cut muscle is carefully sutured to make a tendon so that it can be properly sutured in the face. The gracilis muscle is then disconnected from its blood supply in the leg and brought to the face. The thigh is sutured back together with a surgical drain and a special wrap is placed over the thigh.
The gracilis is then inset into the corner of the mouth and upper face where your smile muscles used to be using the created tendon. Then the transplanted muscle’s artery is hand-sutured to the arteries in the neck, and the vein is connected to a neck vein using a vein connector under a high-powered microscope. The nerves are also hand stitched together under a high-powered microscope. Special nerve sheaths are also placed on suture connections in order to improve and expedite nerve growth. The nerves do not function right away, but the surgery creates new pathways or conduits for nerves to grow and therefore create movement on the paralyzed side of the face. The face and neck incision are closed with surgical drains.
What is the recovery after gracilis free flap surgery?
After gracilis free flap surgery you will be admitted to hospital for 7-14 days. This timeline allows your surgeon to monitor the transplant closely, in order to make sure no problems arise with the blood flow. You will be started on aspirin during your hospital stay to help reduced the chance of clotting, which you will continue taking for 1 month after surgery. Your transplant will be monitored with an ultrasound probe multiple times per day and night to ensure that the blood flow through the blood vessels does not become compromised. If there are problems during your recovery, a surgery may be required to re-establish blood flow to muscle.
The recovery can be uncomfortable, but you will be kept comfortable with either oral or iv pain medicine. You will be also on intravenous antibiotics to prevent infection. The donor thigh will be wrapped in special bandage to prevent bleeding under the skin. There will be surgical drains under the skin in the face hidden in your hairline and the thigh. Surgical drains will generally come out on day 3-7 after surgery, depending on the recovery process.
After discharge from the hospital, keeping your head and donor leg elevated will decrease pressure on the incision. You should take it easy for at least two weeks and your doctor will let you know what level of activity you can resume. Call your doctor if you have increasing redness of the incision, fever, bleeding, pus, drainage, the incision opens or you have worsening pain. Also, let your doctor know if you have any other concerns. You will see your surgeon regularly after discharge from the hospital. You usually can be performing normal activities within two weeks of surgery.
What are the risks gracilis free flap surgery?
The risk of any free tissue transplant surgery is free flap loss due to occlusion of blood vessels by a clot. The probability of complete loss of transplant is 0.5-1%. If there are signs of compromise of the blood flow during your admission to hospital, your surgeon will bring you back to the operating room to try to save the transplant by re-establishing the blood flow.
The general risks of any facial surgery include scarring, bleeding, bruising, infection, fluid or saliva collections under the skin, injury to nerves, donor site issues, numbness, the need for additional surgery, hair loss, chronic pain, numbness, temporary or permanent loss of facial movement on the functional side effects of general anesthesia. Preparing for surgery and following your surgeon’s instructions are useful to help minimize risks.