It’s a good thing nerves aren’t claustrophobic, because in many spots in the body they have to make a tight squeeze—through narrow tunnels, beneath a band of fascia, between muscles and bones, and more.
When spaces get too cramped, however, nerves can be damaged or inflamed, causing tingling, numbness, burning or shooting pain, and other issues. This is called nerve compression (or nerve entrapment), and is quite common in the peroneal nerves of the legs and feet for a variety of reasons, including poor diet (particularly too much sugar), poor posture, repetitive injuries, and more.
Common Peroneal Nerve Compression
The common peroneal nerve innervates the lateral side of the lower leg and the ankle. It leaves the sciatic nerve behind the knee, and it enters a tunnel at the lateral side of the knee, formed by the two heads of the peroneus longus muscle. It passes beneath the fibrous border of the peroneus muscle as it leaves the head of the tibia. This narrow region is where the nerve enters the front of the lower leg.
Peroneal nerve entrapment gives sensory symptoms related to numbness or burning pain from the knee to the top of the foot, and motor symptoms that range from the leg giving out to restless leg syndrome. Compression of the peroneal nerve branches is most commonly seen in patients with neuropathy, like diabetes, or in those who have had a knee injury or knee surgery, or who have had a sports injury like a sprained or broken ankle or knee.
The most common site of compression is at the side of the knee, where the nerve is compressed by white fascial structures against the underlying fibula bone. The fascia is released at surgery.
In the surgical treatment of nerve compression, an incision is made beneath the fibular head. (The fibula is indicated by a dashed line beneath the common peroneal nerve and its branches).
Fascia surrounding the nerves to the lateral side of the leg is released. (The fibrous edge of the peroneus longus m. is divided and the muscle is shown slightly pulled away from the nerve at the site of incision).
Deep Peroneal Nerve Compression
The next most common site of compression is at the top of the foot where a small tendon compresses the deep peroneal nerve against the underlying bone. Symptoms here are only sensory, and may feel like a knife sticking in the top of the foot, and pain between the first and second toes. This happens after a crush injury to the foot, wearing tight shoes or tightly laced boots, a broken foot bone, or foot surgery. The treatment is to remove the small tendon and decompress the nerve.
In the surgical treatment of deep peroneal n. entrapment in the foot, a ligament from the extensor digitorum brevis m. that crosses over the deep peroneal nerve, putting pressure on it and causing pain, is released, as indicated by the dashed lines in the inset to the right.
Superficial Peroneal Nerve Compression
The least common site is in the lateral leg where the superficial peroneal nerve can be compressed. This may occur in young athletes and require the white fascial covering of the muscles to be released. The symptoms are pain and burning on the outside of the foot while exercising. This area can be damaged in soccer or with a broken fibula or crush injuries.
Trust Houston’s Top Extremity Nerve Surgeon for Peroneal Tendon Issues
A past president of the American Association of Extremity Nerve Surgeons, Dr. Parker has decades of experience treating cases of nerve compression throughout the legs, ankles, and feet. Our office in Houston has helped patients from around the country and the world, and can help you too. To schedule an appointment, give us a call at 281-497-2850.