Drop Foot Syndrome
Causes and Treatments of Drop Foot Syndrome
Drop foot syndrome is an uncomfortable and distressing problem that affects how a person walks. People with drop foot are unable to fully lift their foot off the ground while walking and may drag their toe and slap their foot on the ground when coming down. As a result they may walk with exaggerated hip or knee movements to help their toes clear the ground, often appearing as though they are walking up stairs. This condition is usually a symptom of a more serious or complex condition and may require complex treatments. It may be temporary or permanent. Drop Foot syndrome may be caused by a variety of factors, including many neurological diseases, paralysis of muscles, or injuries to the legs or hips. Other causes may include stroke, drug toxicity, post-surgical infections, diabetes and tumors of the brain or spinal cord. It can affect both right and left feet equally.
The legs have many nerves that run down them to help transmit signals to facilitate movement and provide sensations for normal walking. The sciatic nerve runs down from the pelvic cavity then splits into the peroneal and tibial nerves located on the front and back of the legs. These then branch into even smaller nerves. Because the perneal nerve has less protective tissues and is located closer to the skin, this makes it more susceptible to injury from trauma or surgery. It is the perneal nerve located behind the knee that causes the symptoms and effects of drop foot.
A crushing, laceration or rupture injury to the perneal nerve disrupts the flow of nerve signals to the foot. Post surgical problems, mostly resulting from total knee or hip arthroplasties, can also alter the flow of nerve signals. Disrupted flow of the nerves can also lead to what is referred to as double crush phenomenon, or the concept that this disrupted flow also makes the perneal nerve even more susceptible to injury from use. Overly constrictive dressings or a post surgical hematoma can cause damage to the perneal nerve, resulting in drop foot syndrome. Because they directly affect the nerves, more complex neurological disorders such as Multiple Sclerosis, ALS, Parkinson’s disease, Lou Gehrig’s disease or Muscular Dystrophy may also cause nerve and muscular problems with walking and gait. Any condition that causes the paralysis of muscles in the feet or legs can also contribute to this problem, as well as tumors in the brain or spinal cord that may alter nerve flow. There is also some evidence that a behavioral cause of drop foot may result from habitual crossing of the legs, but this condition can be overcome if the habit is stopped.
The symptoms and walking problems associated with this condition can be diagnosed by a physical exam by your doctor, MRI imaging and with electromyelogram techniques. Treatments vary based on the causes and prognosis of the syndrome, but there are several options available. There are many different drugs that your doctor may prescribe. There is also ankle and foot orthosis (AFO) or using braces or inserts to help with ankle stability, foot push off, and toe dorsiflexion. Coupled with physical therapy and exercises, braces and therapeutic nerve stimulation may result in the patient regaining a normal walking motion. For conditions caused by neurological disorders, arthrodesis may be performed into order to help produce a stable and properly aligned ankle.
Devices that produce nerve stimulation may also help. Neuro-prosthesis devices can be attached internally or externally to the patient and stimulate the nerves and muscles at designated portions of the gait. These may help restore nerve function in stroke patients.
There are some surgical options available to patients that suffer from foot drop. A doctor may repair or remove the damaged nerves to help restore nerve signal continuity. They also may graft nerves and transfer tendons from other parts of the body to restore movement, and severe cases may require a lengthening of the Achilles tendon to properly align the foot. These surgical procedures may have long and difficult recovery periods, and also run the risk of complications.
Understanding the causes and treatment options for the conditions that cause drop foot syndrome can help you to overcome this distressing and disabling disorder.