Foot drop, sometimes called drop foot, is a general term for difficulty lifting the front part of the foot. If you have foot drop, you may drag the front of your foot on the ground when you walk.

Foot drop isn't a disease. Rather, foot drop is a sign of an underlying neurological, muscular or anatomical problem.

Sometimes foot drop is temporary. In other cases, foot drop is permanent. If you have foot drop, you may need to wear a brace on your ankle and foot to hold your foot in a normal position.

Foot drop makes it difficult to lift the front part of your foot, so it might drag on the floor when you walk. To counter this, you might raise your thigh when you walk, as if you were climbing stairs (steppage gait), to help your foot clear the floor. This odd gait might cause you to slap your foot down onto the floor with each step you take. In some cases, the skin on the top of your foot and toes may feel numb.

Foot drop typically affects only one foot. Depending on the underlying cause, however, it's possible for both feet to be affected.

When to see a doctor

If your toes drag the floor when you walk, consult your doctor.

Foot drop is caused by weakness or paralysis of the muscles involved in lifting the front part of the foot. The underlying causes of foot drop are varied and may include:

  • Nerve injury. The most common cause of foot drop is compression of the nerve that controls the muscles involved in lifting the foot. This can happen at the knee or in the lower spine. The nerve can also be injured during hip or knee replacement surgery. Long-term nerve damage associated with diabetes can also cause foot drop.
  • Muscle or nerve disorders. Various forms of muscular dystrophy, an inherited disease that causes progressive muscle weakness, may contribute to foot drop. Other disorders, such as polio or Charcot-Marie-Tooth disease, also can cause foot drop.
  • Brain and spinal cord disorders. Disorders that affect the spinal cord or brain — such as amyotrophic lateral sclerosis (ALS), multiple sclerosis or stroke — may cause foot drop.

The peroneal nerve controls the muscles that lift your foot. This nerve runs near the surface of your skin on the side of your knee closest to your hand. Activities that compress this nerve can increase your risk of foot drop. Examples include:

  • Crossing your legs. People who habitually cross their legs can compress the peroneal nerve on their uppermost leg.
  • Prolonged kneeling. Occupations that involve prolonged squatting or kneeling — such as picking strawberries or laying floor tile — can result in foot drop.
  • Wearing a leg cast. Plaster casts that enclose the ankle and end just below the knee can exert pressure on the peroneal nerve.

You're likely to start by seeing your family doctor or regular health care provider. Depending on the suspected cause of foot drop, you may be referred to a doctor who specializes in brain and nerve disorders (neurologist).

Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared for your appointment. Here's some information to help you.

What you can do

  • Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
  • Take note of key personal information, including any major stresses or recent life changes.
  • Make a list of all medications, as well as any vitamins or supplements, that you're taking.
  • Write down questions to ask your doctor. Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together.

For foot drop, some basic questions to ask your doctor include:

  • What's causing my symptoms?
  • What kinds of tests do I need?
  • Is my condition likely temporary or chronic?
  • What treatment do you recommend?
  • Do you have any brochures or other printed material that I can take home with me?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions anytime you don't understand something.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

  • When did you first notice symptoms?
  • Are your symptoms present all the time, or do they come and go?
  • Does anything seem to make your symptoms better?
  • Does anything seem to make your symptoms worse?
  • Do you notice any weakness in your legs?
  • Does your foot slap the floor when you walk?
  • Do you have numbness or tingling in your foot or leg?
  • Do you have a history of diabetes?
  • Do you have any other muscle weakness?

Foot drop is usually diagnosed during a physical exam. Your doctor will want to watch you walk and may check a number of your leg muscles for weakness. He or she may also check for numbness on your shin and on the top of your foot and toes. In some cases, additional testing is recommended.

Imaging tests

Foot drop is sometimes caused by an overgrowth of bone in the spinal canal or by a tumor or cyst pressing on the nerve in the knee or spine. Imaging tests can help pinpoint these types of problems.

  • X-rays. Plain X-rays use a low level of radiation to visualize a soft tissue mass or a bone lesion that may be causing your symptoms.
  • Ultrasound. This technology uses sound waves to create images of internal structures. It may be used to check for cysts or tumors that may be pressing on the nerve.
  • Computerized tomography (CT scan). Computerized tomography combines X-ray images taken from many different angles to form cross-sectional views of structures within the body.
  • Magnetic resonance imaging (MRI). This test uses radio waves and a strong magnetic field to create detailed images. MRI is particularly useful in visualizing soft tissue lesions that may be compressing a nerve.

Nerve tests

Electromyography (EMG) and nerve conduction studies measure electrical activity in the muscles and nerves. These tests can be uncomfortable, but they're very useful in determining the location of the damage along the affected nerve.

Treatment for foot drop depends on the underlying cause. If the underlying cause is successfully treated, foot drop may improve or even disappear. If the underlying cause can't be treated, foot drop may be permanent.

Specific treatment for foot drop may include:

  • Braces or splints. A brace on your ankle and foot or splint that fits into your shoe can help hold your foot in a normal position.
  • Physical therapy. Exercises that strengthen your leg muscles and help you maintain the range of motion in your knee and ankle may improve gait problems associated with foot drop. Stretching exercises are particularly important to prevent the development of stiffness in the heel.
  • Nerve stimulation. Sometimes stimulating the nerve that lifts the foot improves foot drop.
  • Surgery. In cases where foot drop is relatively new, nerve surgery may be helpful. If foot drop is long-standing, your doctor may suggest surgery that fuses ankle or foot bones or a procedure that transfers a functioning tendon to a different position.

Because foot drop can increase your risk of tripping and falling, you might want to take these precautions around your house:

  • Keep all floors clear of clutter.
  • Avoid the use of throw rugs.
  • Relocate electrical cords away from walkways.
  • Make sure rooms and stairways are well lit.
  • Place fluorescent tape on the top and bottom steps of stairways
Nov. 10, 2011