What is the best treatment approach for an adult patient with a history of neurological condition or traumatic injury presenting with foot drop?

Treatment of Foot Drop

Ankle-foot orthoses (AFOs) are the first-line treatment for foot drop, as they are the most effective method for compensating motor impairments, improving mobility, and normalizing ankle and knee kinematics. 1

Initial Assessment and Etiology

Before initiating treatment, determine the underlying cause through:

• Neurological localization: Identify whether the lesion is at the common peroneal nerve (most common), L5 nerve root, lumbar plexus, sciatic nerve, or central nervous system 2, 3
• Nerve conduction studies and EMG: Essential for localizing the injury site, establishing severity, and predicting recovery 2
• Imaging studies: MRI for suspected radiculopathy or central causes; ultrasound, CT, or MRI for peripheral nerve lesions along the sciatic nerve or popliteal fossa 2, 3

Common pitfall: Assuming all foot drop is due to peroneal nerve injury at the fibular head—always evaluate for L5 radiculopathy and proximal sciatic nerve lesions, as these require different management strategies 2, 3

First-Line Conservative Management

Ankle-Foot Orthoses (AFOs)

AFOs should be prescribed immediately for any patient with significant foot drop causing gait impairment, as they:

• Maintain the foot in neutral position during swing phase, preventing toe dragging 1, 4
• Improve gait velocity and stride length 1
• Reduce energy cost of walking 1
• Normalize paretic ankle and knee kinematics 1

Functional Electrical Stimulation (FES)

FES is an equivalent alternative to AFOs and can be offered based on patient preference 1, 4:

• Works by electrically stimulating the peroneal nerve during swing phase 1
• Can be delivered via surface electrodes or implantable nerve stimulators 1
• May help maintain muscle mass through active contraction compared to passive orthoses 1, 4
• Equally effective as AFOs in improving gait speed 1

Physical Therapy (Mandatory Regardless of Other Treatments)

All patients with foot drop require intensive physical therapy 1, 4:

• Intensive, repetitive mobility-task training 1, 4
• Balance and functional exercises with gait training 1
• Strength training and moderate-intensity aerobic activity 1
• Circuit training in group settings 1

Surgical Indications

For Compressive Neuropathies

Any patient with clinically suspected compressive peroneal neuropathy at the fibular head should be informed about surgical decompression, which can be performed with minimal risk 3:

• Consider neurolysis if there is realistic chance of nerve recovery 3
• Timing depends on severity and progression of symptoms 5

For Disc Herniation Causing Foot Drop

Urgent surgery (within 4-24 hours) is indicated for progressive neurologic deterioration, as delayed surgery results in incomplete recovery 4:

• Immediate MRI required for progressive motor weakness developing over hours to days 4
• Surgery reasonable after 4-6 weeks of persistent foot drop despite conservative management 4
• Discectomy alone (without fusion) is the standard surgical approach—fusion should only be added for preoperative instability or recurrent herniation with chronic axial pain 4

Critical pitfall: Delaying imaging in patients with progressive weakness or cauda equina symptoms (urinary retention, bowel dysfunction) worsens outcomes 4

For Permanent Foot Drop

When nerve recovery is not expected, tendon transfer surgery should be considered 5, 6, 3:

• Posterior tibial tendon transfer is the most common palliative procedure 6
• Ankle arthrodesis is an alternative for severe cases 6
• Goals include producing a balanced functional foot and reducing dependence on braces 7

Cause-Specific Considerations

Habitual Leg Crossing

Most patients with peroneal neuropathy from habitual leg crossing improve when they stop this habit—conservative management with behavior modification should be attempted first 2

Spastic Foot Drop

Botulinum toxin injections should be evaluated for patients with spastic foot drop 3

Multiple Sclerosis

Dalfampridine (10 mg twice daily) is FDA-approved to improve walking speed in MS patients, though this addresses the underlying MS pathology rather than foot drop specifically 8

Treatment Algorithm

For acute/subacute foot drop (<6 weeks):

• Immediate AFO or FES fitting 1, 4
• Initiate physical therapy 1, 4
• Investigate underlying cause with nerve studies and imaging 2, 3
• If compressive lesion identified with realistic recovery potential, refer for surgical evaluation 3

For chronic foot drop (>6 weeks) without recovery:

• Continue AFO/FES and physical therapy 1, 4
• Consider tendon transfer surgery if patient desires improved function without orthosis 6, 7
• Ankle arthrodesis reserved for severe, refractory cases 6

For progressive weakness or cauda equina symptoms:

• Immediate MRI and urgent neurosurgical consultation 4
• Surgery within 4-24 hours to prevent permanent nerve damage 4