Foot Drop: Looking Beyond Common Peroneal Nerve Palsy: A Neurophysiology Centre Experience

Area of Science:

• Neurology
• Neurophysiology

Background:

• Foot drop presents with varied etiologies, severity, and prognoses, posing diagnostic challenges.
• Understanding the underlying causes is essential for effective patient management and treatment strategies.

Purpose of the Study:

• To characterize the diverse etiologies of foot drop.
• To evaluate the diagnostic utility of neurophysiologic testing, including nerve conduction studies (NCS) and electromyography (EMG), in foot drop assessment.

Main Methods:

• Retrospective review of 59 consecutive foot drop referrals to a university hospital's neurophysiology department over two years (2012-2013).
• Analysis of initial working diagnoses and the impact of NCS/EMG findings on diagnosis.

Main Results:

• Common peroneal nerve palsy accounted for just over half of the cases.
• Central nervous system origins and motor neuron disease were identified in 5% each.
• Diabetes (10%) and cancer (12%) were significant contributing factors; 8% of cases were bilateral.
• NCS/EMG changed the initial diagnosis in 27% of cases and revealed additional remote pathologies in one-third of all cases.

Conclusions:

• Foot drop etiology is multifactorial, including peripheral nerve issues, central nervous system disorders, and systemic diseases.
• Neurophysiologic testing (NCS/EMG) is highly valuable, not only confirming diagnoses but also uncovering unexpected coexisting pathologies.
• Central and proximal causes of foot drop are underrecognized and warrant thorough investigation.