What is the peroneal nerve?
The common peroneal nerve branches from the sciatic nerve. It includes the deep and superficial peroneal branches. These nerves provide sensation to the anterior (front) and lateral (side) parts of the legs and to the top of the feet. They innervate muscles in the legs which lift the ankle and toes upward (dorsi flexion).
What is peroneal nerve injury (foot drop)?
A peroneal nerve injury (also called foot drop or drop foot), is a peripheral nerve injury that affects a patient’s ability to lift the foot at the ankle. While foot drop injury is a neuromuscular disorder, it can also be a symptom of a more serious injury, such as a nerve compression or herniated disc.
Causes of peroneal nerve injury (foot drop)
Foot drop injury can be caused by an injury to the spinal cord or from other underlying diseases, such as amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), or Parkinson's disease. Sometimes, drop foot is a complication from hip replacement surgery, or other injuries (e.g., knee or joint dislocation or fracture, herniated disc).
Symptoms of peroneal nerve injury (foot drop)
Symptoms of peroneal nerve injury (foot drop) may include:
- Inability to point toes toward the body (dorsi flexion)
- Numbness (on the shin or top of the foot)
- Loss of function of foot
- High-stepping walk (called steppage gait or footdrop gait)
Diagnosis of peroneal nerve injury (foot drop)
Proper diagnosis of drop foot requires the expert attention of experienced neurologists and nerve specialists.
Diagnosis will include:
- A comprehensive clinical exam, including neurological exams
- Complete medical history
- Electrical testing
- Imaging studies, such as X-rays or high-resolution 3-T MRI (magnetic resonance imaging)
Diagnosis is necessary to determine the cause of foot drop, so the appropriate treatment plan, including a surgical option, is considered.
Treatment for peroneal nerve injury (foot drop)
Depending on the severity of your drop foot injury, your physician may recommend the following:
Nonsurgical treatment for peroneal nerve injury (foot drop)
- Orthotics, including braces or foot splints, which may be custom-built into the patient’s shoe
- Physical therapy, including gait training
Surgery for peroneal nerve injury (foot drop)
Surgical treatment for drop foot depends on the cause of the injury. A physician may recommend decompression surgery, nerve sutures, nerve grafting, or nerve transfer or tendon transfer.
Dr Allan Belzberg is a world-renowned neurosurgeon in the treatment of peripheral nerve injuries. He treats on average 500 nerve injuries every year and has published research publications focusing on improving surgical repairs of nerve injuries and discovering new treatment options. Catch up on the latest research on nerve injuries.