Free Functional Muscle Transfer Surgery (FFMT) Risks and Complications

Free functional muscle transfer surgery (FFMT) and alternative treatments:

Free functional muscle transfer involves taking a muscle from an area of the body where it can be spared and transferring it to an area of greater need. It requires the artery, vein and nerve to the muscle to be repaired using microsurgical techniques and is dependent on nerve regrowth to achieve movement. This process can take up to 3 years to become evident and is not guaranteed.

Alternative treatments include tendon transfer surgery, tenodesis, the use of an orthotic splint or not doing anything.

Risks and complications of surgery:

Anyone considering surgery should approach the decision with a healthy amount of respect and caution especially when the surgery is elective (or planned) and is non-essential surgery (as FFMT surgery is). All surgical procedures have limitations in terms achievable outcome and it is important that your expectations match what is possible through surgery. The choice to go ahead with surgery is always (or should always be) taken after due consideration of the risk benefit balance for the procedure. Although the majority of patients do not experience problems it is important that you fully understand all the potential risks and complications of FFMT surgery. Mr. MacQuillan will have discussed these with risks and complications with you during your consultation however it is important that you take the time to read over them again prior to your next consultation.


It is possible, though unusual, to experience a bleeding episode during or after surgery. Drains are often used to reduce the risk of haematoma formation (a collection of blood within the surgical site beneath the skin) post operatively. Significant post-operative bleeding will require a return to theatres to remove the collection of blood and seal (coagulate) any bleeding points. Avoid the use of Aspirin for 2 weeks prior to surgery as this increases the propensity to bleed, as can certain other medications (particularly non-steroidal anti-inflammatory medications, if in doubt please ask Mr. MacQuillan). Significant bleeding is unusual with FFMT surgery but if this occurs a blood transfusion may be required. High blood pressure is a risk factor for having a post-operative bleed, as is taking certain dietary supplements, in addition to the medications described above. The facial skin is at risk of pigmentation, poor healing or necrosis in the event of a significant haematoma and this can result in adverse scarring.

Blood Transfusion:        

If blood transfusions are needed to treat blood loss, there is a risk of blood-related infections such as hepatitis and HIV (AIDS). Heparin medications that are used to prevent blood clots in veins can produce bleeding and decreased blood platelets.


Whenever the skin is cut there is always the risk of infection. With FFMT surgery the risk of infection is low, but if it occurs it may require further treatment ranging from specialist dressings, to antibiotics or hospitalization and can in certain circumstances require further surgery. Infection can affect either the donor site (where the muscle is taken from) or the recipient site (where the muscle is placed).

Changes in sensation:   

Patches of numbness or decreased sensation around the sites of incisions in FFMT surgery are common however these usually resolve with time. It is possible that these changes can be permanent. Very infrequently pain or uncomfortable sensations may be caused nerve entrapment within scar tissue (neuropathic pain). An area at particular risk is the inner aspect of the foot in the territory of the saphenous nerve.

Contour irregularities of the skin: 

Following FFMT surgery it is possible to get loss of smoothness of the surface of the skin (depressions or irregularities of the contours of the skin). It is also possible to get corrugation or pleating of the scar, tethering of the scar to underlying tissues and ‘dog ear’ formation at the ends of the scar. Such problems usually respond to massage and maturation of the scar with time, though very infrequently may require additional surgery to correct them. This can affect either the donor site or the recipient site.


It is normal for scars to heal well following FFMT surgery however adverse scarring is always a possible outcome following any form of surgery. Scars can appear thick, red and raised all or part of the way along the incision line (a hypertrophic scar) or more rarely can involve tissues beyond the incision itself (and can resemble a badly healed burn), this is known as a keloid scar. Additionally scars can tether to underlying structures or become abnormally pigmented. It is possible that additional treatments may be required for adverse scarring.

Skin discolouration:       

Although bruising (together with swelling) is an inevitable consequence of lift surgery it is possible to get pigmentation changes in the skin nearby to the site of surgery. In Caucasian skin this often takes the form of increased pigmentation or darkening of the skin, in darker skin colours pigmentation may decrease around the scar site and lighten. With extensive bruising it is possible to get permanent increased pigmentation within the bruised areas (though this is unusual).

Fat necrosis:                

Fat cells in the subcutaneous tissue (under the skin) have a relatively poor blood supply and are quite susceptible to traumatic damage. With the effects of surgery it is possible for some of the fatty tissue to die and form scar tissue (which can be felt a lumpiness beneath the skin). If there are large areas of fatty tissue that suffer from necrosis this may require removal, or can result in prolonged discharge from the incision. If an area of fat necrosis became infected this would cause and abscess, which would require surgical drainage. It is possible that skin contour abnormalities can be caused by fat necrosis.

Seroma formation:        

A seroma can be best thought of a collection of fluid beneath the skin at a surgical site. The composition of a seroma is much the same as that of blood but without the actual blood cells (it contains similar proteins and salts to blood) and is usually the result of lymphatic fluid accumulation (this is the 10% of the fluid that escapes from capillaries within tissues but does not return back to the veins via the small blood vessels but rather by the lymphatic drainage vessels) or by direct production from inflamed tissue (think of the tissues ‘sweating out’ the fluid). If this occurs there is the possibility it will need to be drained (often by simple aspiration with a needle or syringe, though in rarely can require a further operation to remove completely). If a seroma were to become infected (the leg donor site being the commonest location) then this would require a return trip to theatres and a washout of the abscess.


There will be asymmetry of the legs following the procedure both in terms of scarring and possibly overall leg bulk as a result of harvesting of the gracilis muscle. The recipient sites will also be asymmetric following surgery both in terms of scar placement and muscle bulk.

Compartment syndrome:

If the muscle within a limb becomes swollen it can lose its blood supply – this requires emergency treatment to decompress the muscles in the form of a fasciotomy. Further reconstructive surgery may be required (such as a skin graft) and the muscle may die and need to be debrided. This can affect both operated and non operated limbs.

Delayed healing:

Wounds can break down following surgery (wound dehiscence) or after suture removal or may be slow to heal. If this occurs dressings may be required for a prolonged period of time (weeks to months) prior to wound healing and in occasional cases a further operation may be needed. Scar revision may be necessary in cases of delayed wound healing.

Skin necrosis:   

If the blood supply to the skin is insufficient following surgery (which can be for a variety of reasons) the skin, particularly at the incision site, can necrose (die). If this happens the skin will form an eschar (scab) which may need to be removed surgically. Dressings are likely to be required for a period of time and further surgery may be needed.

Damage to deeper structures:    

The deeper tissues of the limbs are at risk of damage during a FFMT surgery. The blood vessels, muscle and nerves are the areas of particular concern and the risk varies depending on the type of procedure being performed. The injury may be temporary or permanent and may lead to limb threatening sequelae requiring additional surgery. Limb loss may be the ultimate result.

Nerve injury:     

Both the motor and sensory nerves that supply the donor and recipient limbs can be damaged in FFMT surgery. This can result in altered sensation, loss of sensation (numbness) or (rarely) pain if a sensory nerve is injured. Impairment or loss of movement to part or all of a limb can occur if a (or multiple) motor nerve (s) is (are) injured. Areas that can be affected if one or more of the nerve to a limb are injured (resulting in partial or complete loss of movement) include the hip, knee, ankle and foot in the leg and the shoulder, elbow, wrist and hand in the arm. If there is loss of sensation or movement this is often temporary and recovers by itself, however with more serious injury to the nerve the loss can be permanent and require further surgery.


You will have pain following surgery. The intensity and duration of the pain varies from individual to individual following face and neck lift surgery. Very infrequently chronic pain due to nerve damage or nerve entrapment in scar tissue may arise following face and neck lift surgery (neuropathic pain).

Microvascular thrombosis:          

Although every effort is made to perform a technically perfect microvascular anastomosis failure of the blood supply to the muscle flap may occur. Buried doppler monitors are used to keep track of blood flow status and if loss of signal occurs this will require a return to theatre. If it is not possible to re-establish blood flow to the flap it would be necessary to remove the flap and abandon the reconstruction.


Most operations involve the routine use of deeply placed sutures (stiches) within and beneath the skin. Such sutures are usually designed to be dissolving however in some individuals they make take longer to dissolve than intended or may provoke a reaction from the body. In such instances they may form small pockets of inflammation (stitch granulomas or abscesses) which resemble an infection but are in fact due to the underlying stitch. Similarly the stitch may poke through the skin and become uncomfortable. In such cases the stitches will require removal.

Donor site problems:                 

It is unusual for patients to experience significant donor site issues however operating on a limb may result in limb dysfunction or reduced level of function (or limb strength). This problem may be temporary or permanent.

Surgical plan:               

Although a pre operative plan will have been discussed prior to the operation, there are multiple ways of undertaking an individual procedure. Each technique has been developed to achieve the same end result (though may result in differing scar patterns). It may sometimes be necessary to alter the initial plan discussed with you at the time of operation due to anatomic considerations that become apparent during the course of the surgery.

Allergic Reactions:        

In rare cases, local allergies to tape, suture material and glues, blood products, topical preparations or injected agents have been reported. Serious systemic reactions including shock (anaphylaxis) may occur to drugs used during surgery and prescription medications. Allergic reactions may require additional treatment.

Deep vein thrombosis, cardiac and pulmonary complications:         

Any procedure requiring general anaesthesia and immobilization for a period of time increases the risk of the formation of blood clots in the legs. Such clots can dislodge and move to the lungs, causing shortness of breath and strain on the heart. Such clots can potentially be fatal. Air travel, inactivity and other factors (medications such as the oral contraceptive pill or increased tendency to form clots) can increase the risk of clot formation. It is important you tell Mr. MacQuillan of any previous history of swollen legs or blood clots prior to surgery. If you experience shortness of breath, chest pains or feel palpitations (abnormal heart beats) following your surgery it is important you seek medical advice immediately.

Non functional result:     

Although good results are expected, there is no guarantee or warranty expressed or implied, on the results that may be obtained. It is possible to re-establish connection of a motor nerve supply to the transferred muscle however sufficient axonal regrowth cannot be guaranteed (this is essentially up to nature) and so no functional outcome can be guaranteed.

Additional or revision surgery:     

If you have a complication following your procedure further surgery (or other interventions) may be necessary in order to obtain optimal results. Although the risks and complications occur infrequently, the above risks are particularly associated with FFMT surgery. In addition to the risks and complications outlined above there are others that can and do occur, though these are even more uncommon. The outcomes of surgery and medicine are influenced by many factors beyond the control of the doctor and as such it is not an exact science. Although good results are expected, there is no guarantee or warranty expressed or implied on the results that may be obtained.