Rectus Muscle Free Flaps for Coverage of Radiated Skull Bone and Cranioplasty Plates

Superficial Temporal Artery and Vein for Recipient Vessels.

The superficial temporal vessels are excellent recipient vessels when planning for free microsurgical tissue transfer of muscle flaps to the skull. The superficial temporal vessels can be easily palpated crossing the zygomatic arch just superior to the root of the ear. The superficial temporal vessels are frequently quite toruous as one dissects proximally. It is perfectly fine to leave the vessel in it's native configuration and anastamose distal to the corkscrew of the artery.



Typically the rectus abdominis muscle provides adequate bulk and surface area to cover plates that are placed on the skull in cranioplasties. The bulk of the muslce helps to obiterate any dead space that may be present after bony debridement.

Once adequte flow is confirmed in the muscle through adequate bleeding and appropriate doppler flow, a skin graft is usually harvested from the lower extremity and then placed on top of the muscle.

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Free Flaps to Poplitieal Artery-Anterior Tibial Artery Saphenous Vein Bypass Grafts

As the population ages, there are an increasing number of patients who have undergone vascular bypass procedures such as popliteal to anterior tibial bypasses with saphenous vein grafts. Often, in the aging population, the only patent blood vessel to the foot is the bypass graft. When these patients incur injuries or wounds to the most distal aspect of the lower extremity, planning free flap reconstruction can be quite challenging.

I have found that in those patients, magnetic resonance angiography and magnetic resonance venograms can be helpful to establishing a correct plan for the outflow of the microvascular anastomosis. In those cases when the saphenous vein has been used, the surgeon must rely on the venae comitantes of adjacent vessels to determine successful outflow.

I have encountered, that even when native arteries have been diseased, and new blood flow has been established via bypass grafts, the venae comitantes are still often of sufficient caliber. In that case it is important for the operating surgeon to determine the location of the bypass graft tract in relation to the defect, and then select an appropriate venae comitantes in the vicinity of the bypass graft.

Either a long and sufficient caliber leash on the venae comitantes should be mobilized, in addition a flap with a long venous leash that can easily be dissected free of the artery should be selected. I have found the rectus muscle to be an excellent muscle for these cases; In that, the muscle is long and wide allowing not only for adequate coverage, but also for greater margin of separation of vascular bypass and location of nearest venae comitantes.

When the rectus has been harvested, it is important for the surgical team to spend sufficient time and care with the deep inferior epigastric artery and vein to allow adequate mobilization between both vessels.

When there is a single vessel run-off to the lower extremity, I find it helpful to perform the arterial end-to-side anastomosis first so that the flap can be rotated to-and-fro. The vein can then be usually anastomosed so that it will not be kinked. If one anastomoses the vein first, the end-to-side arterial anastomosis is often more difficult as the vein anastomosis now prevents the to-and-fro motion of the flap.

When dissecting toward arterialized vein bypass grafts, I find it helpful to gain proximal and distal control with the vascular bull-dog clamps from the vascular set. One must be aware that there is often a significant amount of scar tissue present around these grafts as they have been tunneled from their proximal to distal locations. Once adequate control has been obtained, the operative surgeons need to spend sufficient time dissecting scar off the vessel before they reach lumen.

Once the muscle has been vascularized, the split thickness skin graft can be placed.

Gracilis Free Flaps for Coverage of Achilles Tendon Wounds

It is quite common these days to see defects of the lower extremity in the region of the Achilles tendon. These wound locations are becoming increasingly more common as the population ages, is more active, and is more affected by the possibility of peripheral vascular disease.

When patients have wounds with exposed tendon it is very painful. Often wounds in the location of tendons appear to have pain out of proportion to the depth, size, and condition of surrounding skin or adjacent structures. To put it simply, wounds with exposed tendons are painful!

It is not until these wounds are covered that the patient reports relief from pain and are able to ambulate properly again.

 There are many different options for covering wounds in the distal third of the lower extremity. Depending on the location, depth, structures that are exposed, and location of quality nearby recipient vessel, I often choose among the following free flaps: 1) Rectus Abdominus, 2) Gracilis, 3) Radial Forearm, 4) Latisimus, and 5)Serratus.

The gracilis free flap offers an excellent advantage in some cases in that the surgery is confined to one surgical site and there is minimal donor site morbidity associated with the flap harvest.The gracilis muscle inserts proximally onto the pubic symphysis while the distal insertion is the medial condyle of the tibia. The blood supply of the gracilis is from the ascending branch of the medial femoral circumflex femoral artery and vein.

These blood vessels are often an appropriate size match for the posterior tibial vessels deep distal in the lower extremity.

Free Rectus Muscle Flap to Scalp with Saphenous Vein Graft to External Jugular

Radiation is often a necessary adjuvant in the treatment of many cancers. While radiation is often necessary in cancer therapy, the radiation can also cause damage to normal healthy tissue and prevent wound healing.

When radiation is used on the head, not only can it cause injury to the skin and subcutaneous tissue, it can also cause damage to the underlying bone. When the bone develops osteoradionecrosis, it can often cause wounds to recur or simply become non-healing. When the bone is removed, often a titanium mesh or bone cement is used to cover the brain.

Usually there is not enough tissue on the scalp to close these defects, therefore free tissue transfer and microsurgery is necessary to bring in healthy tissue to the area to close the wounds.

The rectus muscle is a nice muscle to use in this scenario as there is a long pedicle leash and a muscle with a large surface area. Occasionally the superficial temporal artery is of good quality and the vein may be small. In this case we have found that the saphenous vein can be an effective vein graft from the flap to the external jugular. We find that in the past many have not advocated the use of vein grafts. However, often is more advantageous to use a vein graft to a more suitable outflow than to rely on a marginal vein in the vicinity of the wound.

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Limb Salvage with Free Rectus Muscle Flap

Occlusion of vessels of the leg can significantly impair wound healing when the integrity of the skin is violated. In the distal third of the leg where there is limited leg laxity, it is necessary to bring well vascularized tissue from one region of the body to another.

When one of the three blood vessels to the leg is occluded, it is important to maintain the remaining blood supply of the lower extremity. In that case, the rectus muscle is removed from the abdomen and transferred to the leg using and end-to-side anastamosis off of the posterior tibial vessel. Using an end-to-side anastamosis can preserve the blood supply to the foot.

Drains are placed beneath the muscle and the muscle is then covered with a split thickness skin graft. Elevation of the lower extremity is important post-operatively.

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