Common peroneal nerve dysfunction
Neuropathy - common peroneal nerve; Peroneal nerve injury; Peroneal nerve palsy
Common peroneal nerve dysfunction is damage to the peroneal nerve leading to loss of movement or sensation in the foot and leg.
Causes
The peroneal nerve is a branch of the sciatic nerve, which supplies movement and sensation to the lower leg, foot and toes. Common peroneal nerve dysfunction is a type of peripheral neuropathy (damage to nerves outside the brain or spinal cord). This condition can affect people of any age.
Peripheral neuropathy
Peripheral nerves carry information to and from the brain. They also carry signals to and from the spinal cord to the rest of the body. Peripheral n...
Dysfunction of a single nerve, such as the common peroneal nerve, is called a mononeuropathy . Mononeuropathy means the nerve damage occurred in one area. Certain body-wide conditions can also cause single nerve injuries.
Mononeuropathy
Mononeuropathy is damage to a single nerve, which results in loss of movement, sensation, or other function of that nerve.
Damage to the nerve disrupts the myelin sheath that covers the axon (branch of the nerve cell). The axon can also be injured, which causes more severe symptoms.
Myelin
Myelin is an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord. It is made up of protein and fatty ...
Common causes of damage to the peroneal nerve include the following:
- Trauma or injury to the knee
-
Fracture
of the fibula (a bone of the lower leg)
Fracture
If more pressure is put on a bone than it can stand, it will split or break. A break of any size is called a fracture. If the broken bone punctures...
- Use of a tight plaster cast (or other long-term constriction) of the lower leg
- Crossing the legs regularly
- Regularly wearing high boots
-
Pressure to the knee from positions during deep sleep or
coma
Coma
Decreased alertness is a state of reduced awareness. A coma is a state of decreased alertness from which a person cannot be awakened. A long-term co...
- Injury during knee surgery or from being placed in an awkward position during anesthesia
Common peroneal nerve injury is often seen in people:
-
Who are very thin (for example, from
anorexia nervosa
)
Anorexia nervosa
Anorexia is an eating disorder that causes people lose more weight than is considered healthy for their age and height. People with this disorder may...
-
Who have certain
autoimmune
conditions, such as
polyarteritis nodosa
Autoimmune
An autoimmune disorder occurs when the body's immune system attacks and destroys healthy body tissue by mistake. There are more than 80 types of aut...
Polyarteritis nodosa
Polyarteritis nodosa is a serious blood vessel disease. The small and medium-sized arteries become swollen and damaged.
- Who have nerve damage from other medical problems, such as diabetes or alcohol use
-
Who have
Charcot-Marie-Tooth disease
, an inherited disorder that affects all of the nerves
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease is a group of disorders passed down through families that affect the nerves outside the brain and spine. These are calle...
Symptoms
When the nerve is injured and results in dysfunction, symptoms may include:
-
Decreased sensation
, numbness, or tingling in the top of the foot or the outer part of the upper or lower leg
Decreased sensation
Numbness and tingling are abnormal sensations that can occur anywhere in your body, but they are often felt in your fingers, hands, feet, arms, or le...
- Foot that drops (unable to hold the foot up)
- "Slapping" gait (walking pattern in which each step makes a slapping noise)
- Toes drag while walking
- Walking problems
- Weakness of the ankles or feet
- Loss of muscle mass because the nerves aren’t stimulating the muscles
Exams and Tests
Examination of the legs may show:
- Loss of muscle control in the lower legs and feet
- Atrophy of the foot or foreleg muscles
- Difficulty lifting up the foot and toes and making toe-out movements
Tests of nerve activity include:
-
Electromyography
(EMG, a test of electrical activity in muscles)
Electromyography
Electromyography (EMG) is a test that checks the health of the muscles and the nerves that control the muscles.
-
Nerve conduction tests
Nerve conduction tests
Nerve conduction velocity (NCV) is a test to see how fast electrical signals move through a nerve.
-
MRI
MRI
A magnetic resonance imaging (MRI) scan is an imaging test that uses powerful magnets and radio waves to create pictures of the body. It does not us...
- Nerve ultrasound
What other tests are done depend on the suspected cause of nerve dysfunction, and the person's symptoms and how they develop. Tests may include blood tests, x-rays and scans.
x-rays
X-rays are a type of electromagnetic radiation, just like visible light. An x-ray machine sends individual x-ray particles through the body. The im...
Treatment
Treatment aims to improve mobility and independence. Any illness or other cause of the neuropathy should be treated. Padding the knee may prevent further injury by crossing the legs, while also serving as a reminder to not cross your legs.
In some cases, corticosteroids injected into the area may reduce swelling and pressure on the nerve.
Swelling
Swelling is the enlargement of organs, skin, or other body parts. It is caused by a buildup of fluid in the tissues. The extra fluid can lead to a ...
You may need surgery if:
- The disorder does not go away
- You have problems with movement
- There is evidence that the nerve axon is damaged
Surgery to relieve pressure on the nerve may reduce symptoms if the disorder is caused by pressure on the nerve. Surgery to remove tumors on the nerve may also help.
CONTROLLING SYMPTOMS
You may need over-the-counter or prescription pain relievers to control pain. Other medicines that may be used to reduce pain include gabapentin, carbamazepine, or tricyclic antidepressants, such as amitriptyline.
If your pain is severe, a pain specialist can help you explore all options for pain relief.
Physical therapy exercises may help you maintain muscle strength.
Orthopedic devices may improve your ability to walk and prevent contractures . These may include braces, splints , orthopedic shoes, or other equipment.
Contractures
A contracture develops when the normally stretchy (elastic) tissues are replaced by nonstretchy (inelastic) fiber-like tissue. This tissue makes it ...
Splints
A splint is a device used for holding a part of the body stable to decrease pain and prevent further injury.
Vocational counseling, occupational therapy, or similar programs may help you maximize your mobility and independence.
Outlook (Prognosis)
Outcome depends on the cause of the problem. Successfully treating the cause may relieve the dysfunction, although it may take several months for the nerve to improve.
If nerve damage is severe, disability may be permanent. The nerve pain may be very uncomfortable. This disorder does NOT usually shorten a person's expected lifespan.
Nerve pain
Neuralgia is a sharp, shocking pain that follows the path of a nerve and is due to irritation or damage to the nerve. Common neuralgias include:Posth...
Possible Complications
Problems that may develop with this condition include:
- Decreased ability to walk
-
Permanent
decrease in sensation
in the legs or feet
Decrease in sensation
Numbness and tingling are abnormal sensations that can occur anywhere in your body, but they are often felt in your fingers, hands, feet, arms, or le...
-
Permanent
weakness
or
paralysis
in the legs or feet
Paralysis
Muscle function loss is when a muscle does not work or move normally. The medical term for complete loss of muscle function is paralysis.
- Side effects of medicines
When to Contact a Medical Professional
Call your health care provider if you have symptoms of common peroneal nerve dysfunction.
Prevention
Avoid crossing your legs or putting long-term pressure on the back or side of the knee. Treat injuries to the leg or knee right away.
If a cast, splint, dressing, or other pressure on the lower leg causes a tight feeling or numbness, call your provider.
References
King JC. Peroneal neuropathy. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation: Musculoskeletal Disorders, Pain, and Rehabilitation . 3rd ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 75.
Peroneal neuropathy. In: Preston DC, Shapiro BE, eds. Electromyography and Neuromuscular Disorders . 3rd ed. Philadelphia, PA: Elsevier; 2013:chap 22.
-
Common peroneal nerve dysfunction - illustration
Common peroneal nerve dysfunction is a disorder characterized by loss of movement or sensation of the foot and leg caused by damage to the peroneal nerve.
Common peroneal nerve dysfunction
illustration
Review Date: 8/13/2015
Reviewed By: Joseph V. Campellone, MD, Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.