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 a nerve in your leg that controls the muscles involved in lifting the foot. This nerve can also be injured during hip or knee replacement surgery, which may cause foot drop. A nerve root injury ("pinched nerve") in the spine can also cause foot drop. People who have diabetes are more susceptible to nerve disorders, which are associated with 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.