From the Guidelines
Foot drop, or peroneal nerve palsy, is most commonly caused by peripheral neuropathy, which is often a complication of diabetes, leading to nerve damage and subsequent muscle weakness or paralysis 1. The pathophysiology of foot drop in diabetic patients typically involves a break in the protective cutaneous envelope, usually due to trauma or ulceration, which can lead to infection and further complications. Key factors that contribute to the development of foot drop include:
- Peripheral neuropathy, which can cause sensory, motor, and autonomic nerve damage
- Foot ischemia, related to peripheral arterial disease, which can increase the risk of infection and worsen outcomes
- Hyperglycemia-induced advanced glycation end products, persistent inflammation, and apoptosis, which can lead to chronic wounds
- Traumatic etiology, deep or long-standing wounds, and chronic renal failure, which can predispose to foot infection In the context of diabetic foot infections, the anatomy of the foot and the presence of bacterial virulence factors can also play a role in the development of foot drop. Therefore, management of foot drop should prioritize addressing the underlying cause, such as treating peripheral neuropathy and preventing further complications, in order to improve morbidity, mortality, and quality of life 1.
From the Research
Causes of Foot Drop (Peroneal Nerve Palsy)
The causes of foot drop (peroneal nerve palsy) are diverse and can be attributed to various factors, including:
- Peroneal neuropathy at the neck of the fibula, which is the most frequent cause 2, 3
- Anterior horn cell disease 2, 3
- Lumbar plexopathies 2, 3
- L5 radiculopathy 2, 3
- Partial sciatic neuropathy 2
- Compartment syndromes of the lower leg 3
- Central nervous system related neuropathies, such as brain tumors 3
- Chiari malformation type 1, a rare cause of foot drop 4
- Habitual leg crossing, which can cause peroneal neuropathy at the fibular neck 2
Diagnosis and Evaluation
A meticulous neurological evaluation is essential in ascertaining the site of the lesion and determining the cause of foot drop 2. Additional diagnostic tools, such as:
- Nerve conduction and electromyographic studies, can help localize the site of injury and establish the degree of damage 2, 5
- Imaging studies, including ultrasonography, CT, and MR imaging, can aid in establishing the cause of foot drop 2
- A detailed history and physical examination are crucial in understanding the underlying pathophysiology and capacity for spontaneous recovery 5