Foot drop, the inability to lift the front part of the foot, is usually caused by nerve injury or disorders of the brain, spine or muscles, according to WebMD. Other symptoms include dragging the toes, lifting the knees higher than usual or swinging the leg wide while walking.
Most incidences of foot drop are caused by injury to the peroneal nerve, which runs along the back of the knee and the top of the shin, explains WebMD. Its proximity to the skin's surface makes the peroneal nerve easy to injure in sports or when squatting too long or sitting cross-legged for extended periods. Sometimes diabetes, childbirth or hip or knee replacement surgery can affect the peroneal nerve enough to cause foot drop. Several brain and spinal disorders can cause foot drop. They include multiple sclerosis, stroke, cerebral palsy and Charcot-Marie-Tooth disease.
Conditions that weaken or destroy muscle tissue can also lead to foot drop, states WebMD. Chronic conditions such as polio, muscular dystrophy and Lou Gehrig's disease may be a factor. The most common treatment for foot drop is a lightweight brace to support the leg. Doctors may prescribe physical therapy to strengthen the leg and foot muscles. Surgery may be required to repair damaged nerves.