What Is the Common Peroneal Nerve?

It is one of the two terminal branches of the sciatic nerve, and is composed of fibers from the anterior branches of the spinal nerves 4 to 5 and the iliac 1 to 2. After the sciatic nerve is separated, it goes down along the medial edge of the biceps femoris, penetrating the proximal end of the fibula longus muscle around the fibula neck to the front of the fibula neck, and is divided into the anterior peroneal and deep peroneal nerves. Its muscles innervate the lateral group of the calf muscles, the anterior group and the dorsum muscles; the skin branches are clothed on the skin of the lateral surface of the calf, the back of the feet and the back of the toes.

It is one of the two terminal branches of the sciatic nerve, and is composed of fibers from the anterior branches of the spinal nerves 4 to 5 and the iliac 1 to 2. After the sciatic nerve is separated, it goes down along the medial edge of the biceps femoris, penetrating the proximal end of the fibula longus muscle around the fibula neck to the front of the fibula neck, and it is divided into the anterior and deep peroneal nerves. Its muscles innervate the lateral group of the calf muscles, the anterior group and the dorsum muscles; the skin branches are clothed on the skin of the lateral surface of the calf, the back of the feet and the back of the toes.

Chinese name

Common peroneal nerve

Foreign name

Common peroneal nervous

Location

Down along the upper and outer edges of the popliteal fossa through the inner edge of the biceps femoris

Companionship

Accompanying anterior tibial artery

Anatomy of the common peroneal nerve

After the common peroneal nerve is separated from the upper corner of the popliteal fossa by the sciatic nerve, it descends outward along the medial edge of the biceps femoris muscle, covering about 1/3 of the cases. Later, the common peroneal nerve passes behind the lateral head of the gastrocnemius muscle, and is located in the depression between the biceps femoris tendon and the lateral edge of the gastrocnemius tendon, where it directly adheres to the knee joint fiber capsule. Common peroneal nerve Behind the head of the fibula and around the neck of the fibula, close to the periosteum and enter the gastrocnemius muscle, where it is divided into superficial and deep peroneal nerves.

1 Superficial peroneal nerve: It descends between the long and short fibula and long extensor toes, and sends out muscles to innervate the long and short fibula. Its trunk line is downward, and a deep fascia is penetrated under the lower leg. Divided into the medial and lateral dermal branches, distributed on the inner side of the calf, the back of the foot and the skin of each toe except the border of the toe and the second toe.

2 Deep peroneal nerve: on the deep side of the long peroneal long muscle, the common peroneal nerve is sent around the peroneal head, and then passes through the long peroneal muscle, between the long toe extensor and the tibialis anterior muscle, in the calf with the anterior tibial artery The anterior interosseous membrane descends to the front of the ankle joint, and it branches along the way to dominate the tibialis anterior muscle, toe long extensor, long extensor, and third fibula muscle, and the joint branches to the ankle. The deep nerve is divided into two terminal branches in front of the ankle: the lateral branch is on the deep side of the short toe extensor, which innervates the short extensor, toe extensor, dorsal interosseous muscle, and nearby small joints; Travel forward to the 1st metatarsal space and distribute on the back of the 1st metatarsal space; the lateral sural cutaneous nerve and the medial sural cutaneous nerve merge into the sural nerve.

Body surface projection of the common peroneal nerve: Draw a line from the upper corner of the popliteal fossa to the fibula head, which represents the stroke of the common peroneal nerve.

Common peroneal nerve injury

The common peroneal nerve is also known as the peroneal nerve or external phrenic nerve, which comes from the posterior thigh of the 4th and 5th lumbar nerves and the 1st and 2nd phrenic nerves. After leaving the sciatic nerve, follow the deep side of the biceps femoris and pass through the outer edge of the popliteal fossa to the small head of the fibula, then bypass the outer fibula neck, enter the long fibula muscle, turn to the anterior side of the calf, and divide it into two superficial fibula and deep perone nerve. The superficial peroneal nerve is mainly sensory, descending along the peroneal muscle between the peroneus longus and peroneus. After the branches dominate the peroneus longus and peroneus shortus, it goes to the dorsal side of the foot and is distributed on the dorsal skin of the foot. The deep peroneal nerve, also known as the anterior tibial nerve, is dominated by movement. It moves from the lateral side of the fibula neck to the anterior side to the calf extensor muscles and branches dominate, such as the anterior tibialis muscle, long extensor muscles, and third fibula muscle. Short extensor muscles and skin around the back of the first and second toes.

Common peroneal nerve injury is more common. Because it is superficial when passing around the fibula neck, it is particularly vulnerable. Common causes are: local compression, such as fracture and dislocation, improper plaster or splint fixation. Ischemia can be caused by tourniquets or other causes of prolonged ischemia. Pull injury. Above the knee is part of the sciatic nerve injury.

Symptoms and signs appear depending on the level of injury. The calf extensor muscles often atrophy, and the affected foot is drooping and valgus, and cannot be abducted or valgus. Feet and toes cannot be dorsiflexed, and the affected foot should be held high while walking. Feeling of the skin on the back of the foot and the outside of the calf is lost.

Closed injury is usually treated with conservative methods, and braces are used to prevent the foot from sagging. The effect of surgical repair is not satisfactory. For nerve damage that cannot be repaired at a later stage, it can be considered for tendon transposition, three-joint fusion or wearing orthopedic shoes as appropriate.