Foot drop, also referred to as drop foot, is the inability to raise the front portion of the foot. The result of this is that the toes have a tendency to drag on the floor or ground when walking. To avoid this tendency for the toes to drag, a person suffering drop foot may lift their knee higher than is normal with each step, as though they were climbing up stairs. This high-stepping gait is the most common symptom of foot drop.
Foot drop is not considered a disease. Rather, it's a symptom of an underlying problem, either anatomical, muscular or neurological. It can occur in a person of any age and may affect either one foot or, less frequently, both feet at the same time.
Generally speaking, the cause of drop foot is a weakness or paralysis of the muscles used for lifting the foot. There may be numerous causes for this and the variety of treatments available vary, depending on the specific cause.
Common Causes of Drop Foot
The following are some common causes that are known to be responsible for foot drop:
Nerve Injury - injury to spinal nerve roots may be responsible for drop foot, but more commonly it's an injury to the peroneal nerve. This is a branch of the sciatic nerve that runs from the back of the knee to the shin. Because this nerve is very close to the skin's surface it can be easily damaged. This may also cause numbness or pain along the shin or top part of the foot.
The peroneal nerve may be damaged through any of the following:
- Sports injuries
- Long hours spent squatting or sitting cross-legged
- Replacement surgery for a hip or a knee
- Time spent in a leg cast
Spinal or brain disorders – certain neurological conditions may cause drop foot, including:
- MS (Multiple Sclerosis)
- Cerebral Palsy
- Charcot–Marie–Tooth disease(CMT), a hereditary sensory/motor neuropathy of the peripheral nervous system with the characteristic of having a progressive loss of touch sensation and muscle tissue
Muscle Disorders may also play a role in drop foot, including polio, MS (muscular dystrophy) and Lou Gehrig's Disease.
Drop foot is typically diagnosed by your doctor during a physical examination. This would include observing the way you walk, checking your leg muscles for any weakness and examining your shin, foot and toes for numbness.
Some other conditions that may be responsible for drop foot may include bone overgrowth in the spinal canal or pressure on the spine or nerve in the knee by a tumor or cyst. These may be checked by your doctor through any of several imaging tests including X-ray, ultrasound, MRI or CT scan.
Depending on the underlying cause, treatments for foot drop may vary. For certain underlying causes, treatment must be directed to them before the drop foot disorder can be dealt with. An example is a herniated spinal disc in the lower back that may be putting pressure on the nerve going to the leg. The herniated disc must first be treated to see if this will be successful in relieving the foot drop symptoms.
If treatment is successful, the foot drop may improve or disappear altogether. If not, the disorder may be permanent. Some other viable treatments may include:
Lightweight braces or splints – having a brace on your foot and ankle or a splint that goes into your shoe may help in holding your foot in a more normal position.
Nerve stimulation – sometimes stimulating the nerve that lifts the foot may help the condition. Electronic devices may be used that stimulate leg nerves while you're walking.
Physical therapy – certain exercises to strengthen leg muscles and to help in maintaining ankle and knee range of motion may help and improve your gait. Stretching exercises are also important in preventing stiffness.
Surgery – nerve surgery may be recommended to repair a damaged or compressed nerve. Permanent foot drop may be treated by a surgery that fuses the foot and ankle joint or a transfer of tendons from a stronger muscle in hopes of improving stability.
How ankle foot orthotics can help
Those with foot drop can be greatly helped through the use of appropriate ankle foot orthotics. Foot drop can be a danger to the sufferer as there's a tendency to trip, stumble and fall. Your toes may get caught when walking on carpet and walking on uneven surfaces can be especially challenging.
Podiatric medicine has developed numerous products that have been engineered to address the complex and varied mobility issues facing individuals with foot drop. Ankle foot orthotics (AFOs), which envelop the calf as well as the ankle and foot, are designed to support the front of the foot, minimizing flexion in the foot and ankle. They are manufactured in both solid and hinged versions. Foot drop is often treated with a “dynamic assist” AFO, see KLM’s
Motion Pro Dynamic Assist, which has special hinges to encourage “dorsiflexion” of the foot, or lifting the toes toward the knee.
Foot drop is not an uncommon problem and affects millions of people worldwide. As you have learned above, there are a number of means for dealing with the disorder to either cure it completely or to aid the patient in regaining a greater degree of mobility. Often, several solutions working together such as nerve stimulation, physical therapy and orthotics use can bring great relief with this condition.