Edited by Paul Juliano, MD
Transfering the peroneus longus tendon to the peroneus brevis tendon is a procedure where one of the tendons (peroneus longus) on the outside back part of the ankle (posterolateral) is rerouted to attach where the other tendon (peroneus brevis) normally attaches, on the outside of the midfoot.
The main indication for this type of procedure would be dysfunction or disruption of the peroneus brevis tendon, such as may occur in marked peroneal tendonitis. Both of the peroneal tendons serve to move the ankle and foot out to the side (eversion), and to help stabilize the ankle and foot when walking. The peroneus brevis attaches at the base of the mid foot (base of the fifth metatarsal), whereas the peroneus longus tendon runs in a similar direction but then wraps underneath the foot, and attaches on the base of the inside part of the foot (base of the first metatarsal bone).
A second less common indication for a peroneus longus to brevis transfer is if the peroneus longus tendon is overactive, causing the base of the great toe to be driven into the ground with each step. This may be seen in an excessively high arched foot. It is common in a condition like Charcot-Marie Tooth, where patients develop a pronounced high arched foot. When present, it may lead to pain at the base of the great toe. This can usually be managed with orthotics and other non-operative means. However, if non-surgical treatment fails, a peroneus longus to peroneus brevis transfer may be indicated either alone or in combination with other procedures designed to correct the associated deformity.
Performing a peroneus longus to peroneus brevis transfer procedure involves making an incision on the outside back part of the ankle, and exposing both of the peroneal tendons. If the peroneus brevis tendon is injured or disrupted and can not be repaired, it is often advantageous to transfer this tendon into the peroneus longus tendon, which runs besides it. This allows the muscle belly of the peroneus brevis to still function and pull the foot out to the side. A second incision may need to be made more distally, in order to attach or suture the peroneus longus tendon into the base of the fifth metatarsal, where the peroneus brevis tendon inserts.
To be successful, this procedure needs the tendon transfer to heal solidly. This usually requires a minimum of six weeks of either non weight-bearing or relatively limited weight bearing, with the foot and ankle immobilized in either a cast or a CAM walker boot. After this, the ankle is rehabilitated and the muscles are developed so that they can function in the new manner that they are being used.
Potential complications that are specific to this procedure include:
- Sural Nerve Injury. An irritation or injury to the sural nerve is relatively common. The nerve runs near the incision and can be stretched, irritated by scar tissue, or even cut. If a sural nerve injury develops, there will be numbness and/or a burning sensation on the outside of the foot.
- Failure of the tendon repair. Tendon failure is also a possibility. If this occurs, there would be limited or weak movement of the foot and ankle to the outside (eversion).
Edited December 8, 2015