Foot drop is a symptom rather than a condition. It describes the inability to raise the foot upwards (dorsiflex the ankle), as if pulling the toes up towards the shin.
A patient with foot drop may drag the foot along the floor when walking. Or, in order to combat this, they may raise the hip and knee higher so that the foot clears the ground. They may also slap the foot back to the floor once the heel hits the ground as they cannot control the downward motion.
Causes of foot drop
Foot drop may be a temporary condition, or may be permanent, depending on it's cause. There are many different causes which may include:
- Injury to the peroneal nerve (peroneal nerve palsy) .
- Injury to the ankle dorsiflexor muscles, such as Tibialis Anterior.
- Spinal canal stenosis.
- Peripheral neuropathies.
- Compartment syndromes.
- Muscular conditions such as Muscular Dystrophy.
- Neurodegenerative disorders such as Multiple Sclerosis.
- Following a stroke.
- Motor neuron disorders, e.g. Polio.
- Following surgery (such as knee replacement). This may be due to a haematoma causing compression or irritation of the nerve which is temporary, or nerve damage during surgery.
- Habitual crossing of the legs when sitting - compresses the peroneal nerve.
Diagnosis of foot drop
It is important to establish the cause of foot drop. In some cases it will be obvious and in others it may be more complicated.
If you have foot drop you should visit your Doctor who will observe the injury and look at your medical history for possible causes. If the cause is not clear then diagnostic tests such as an MRI scan, CT scan, EMG (electromyography - to look at the nerves) or blood tests for detecting conditions such as Diabetes.
Treatment of drop foot
Treatment of foot drop varies depending on the cause of the problem and how temporary or permanent the condition may be.
Braces and Splints
A foot drop splint is often the first line of treatment. These help to hold the foot up off the ground to make walking easier. These tend to be plastic splints which are inserted into the shoe.
Physical therapy may be used to 're-educate' a patients gait cycle (walking pattern). A physical therapist may also be used in treating the underlying cause of the foot drop. For example a back strengthening rehabilitation programme for those with spinal canal stenosis.
Nerve stimulation may be effective in those which dropped foot is due to a stroke. A battery operated unit may be strapped to the leg just below the knee, or in some cases a tiny stimulator may be implanted within the leg.
Treatments for other causes of foot drop may include epidural or steroid injections and anti-inflammatory medications.
Surgery may be required in a number of the conditions listed above, usually once non-surgical treatment has failed. Surgery will vary depending on the cause of the drop foot. It may be aimed at the cause such as with spinal canal stenosis or other back problems, or may be used to fuse the ankle joint to prevent the downward drop.