Foot weakness refers to a condition where there is a decrease in the usual strength or movements of the foot. This can be due to a variety of factors, including simple injury or fatigue, disorders of the nervous system, or other health disorders like diabetes or rheumatic diseases. Severity of the condition can range from mild discomfort to total inability to use the affected part.
Injury or fatigue can lead to a feeling of weakness. If the foot has been injured, there may be improper blood flow through the leg and foot area, causing foot weakness. Excessive use of leg muscles during or after strenuous activities like running or biking may cause tiredness and cramping, resulting in weakness. Lack of hydration or potassium imbalance may also lead to cramping and weakness.
Weakness in the foot is one symptom that could indicate a disorder of the nervous system, such as Charcot-Marie-Tooth disease. This is a neurological disease where there is degeneration of nerves, usually starting in the hands and feet. Multiple sclerosis, an autoimmune disease that attacks the nervous system and causes damage to the nerves, may also cause muscle weakness, difficulty walking, and possible paralysis.
Foot drop is a condition characterized by an inability to move the ankle and to flex the toes upward. This results in an abnormal gait, where the foot slaps down onto the floor when the affected person attempts to walk. The condition is caused by damage to the peroneal nerve, which is responsible for upward flexion of the toes. People suffering from foot drop may experience both ankle and foot weakness.
Weakness in the foot is also associated with medical conditions like diabetes and poliomyelitis. Diabetic neuropathy is a complication of diabetes wherein nerve damage occurs as a result of long-term high blood-sugar levels. Typical symptoms of the condition are pain, numbness, or tingling sensations in the feet. Poliomyelitis is an infectious disease caused by a virus that can attack the central nervous system and destroy motor neurons. One of its possible symptoms is muscle weakness, sometimes leading to leg paralysis.
Another possible and common cause of foot weakness is rheumatoid arthritis (RA), an inflammatory disorder that primarily affects synovial joints. A person suffering from RA will typically experience a swelling in the affected joints, which feel stiff, warm, and painful. The stiffness in the joints caused by RA is yet another example of foot weakness.