Definition

The peroneal nerve is found on the outside part of the lower knee. This nerve is responsible for transmitting impulses to and from the leg, foot, and toes. When damaged, the muscles innervated by the nerve may become weak and sensation may be lost. A condition called foot drop can occur. Foot drop is the inability to raise the foot upwards.

Causes

A peroneal nerve injury is commonly caused by an injury to the leg.

Trauma to the nerve can occur with:

    
  • Broken leg bone
  • Knee injury
  • Surgery to leg or knee
  • Ankle injuries
  • Peroneal Nerve Damage After Ankle Injury and Repair

    Peroneal injury

    Neuropathy is nerve damage.

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    Prolonged pressure on the nerve can occur with:

        
  • Sitting position
  • Cast on lower leg, particularly if it is too tight
  • Blood clots, tumors, or other masses
  • Risk Factors

    Factors that may increase your chance of peroneal nerve injury include:

        
  • Recent trauma to leg
  • Having a cast on your leg
  • Frequently sitting with legs crossed
  • Long periods of bedrest
  • Being very thin
  • Symptoms

    Peroneal nerve injury may cause:

        
  • Numbness or tingling in the lower leg
  • Pain in foot or shin
  • Foot weakness
  • Prickling sensation
  • Pins and needles sensation
  • Diagnosis

    Your doctor will ask about your symptoms and medical history. A physical exam will be done. An important part of your physical will be checking how well your nerves and muscles are working in certain parts of your leg. Your doctor may want to watch you as you walk.

    Tests may include the following:

        
  • X-rays
  • MRI
  • Electromyography (EMG) or other nerve conduction tests
  • Treatment

    Talk with your doctor about the best plan for you. Options include the following:

    Physical Therapy

    A therapist will work with you to strengthen your leg and foot muscles.

    Orthotics

    An ankle and foot brace is used to treat foot drop.

    Surgery

    In some cases, surgery is used to treat a peroneal nerve injury. Surgical involves taking pressure off the nerve (decompressive surgery).

    Prevention

    To reduce your chance of getting a peroneal nerve injury, take these steps:

        
  • Avoid crossing your legs
  • Move around frequently
  • If you work on your knees, wear protection
  • If you have a cast on your leg, let your doctor know right away if you are having numbness or tingling.