1502 - Bilateral Peroneal Neuropathy Following Rapid Weight Loss After Stroke: A Case Report

Case Diagnosis: Bilateral peroneal neuropathy at the fibular head secondary to significant post-stroke weight loss.

Case Description: Seven months prior to presentation, the 44-year-old female patient experienced a right paramedian stroke causing left-sided hemiparesis. She subsequently regained full strength over four months with concurrent, intentional, 80-pound weight loss as part of an overall health plan. Six months post-stroke, she developed left dorsiflexion weakness (2/5) progressing to bilateral weakness (right 4/5). Gait assessment revealed left hip hiking and foot slapping. Brain and lumbar spine MRI were unremarkable; EMG demonstrated bilateral focal peroneal neuropathy at the fibular head. Metabolic and nutritional labs were unremarkable. She failed to improve with bracing and physical therapy. Surgical decompression of the peroneal nerves at the fibular head was performed, resulting in complete resolution of symptoms after six weeks of therapy.


Discussions: Foot drop has a broad differential diagnosis, including recurrent stroke, peroneal nerve entrapment or compression, lumbar radiculopathy, lumbosacral plexopathy, motor neuron disease, peripheral polyneuropathy, metabolic derangements, and iatrogenic injury. In this case, central causes were concerning due to initial weakness presenting ipsilateral to her prior hemiparesis. Peroneal nerve palsy associated with weight loss is often due to loss of protective subcutaneous fat, increasing vulnerability to compression at the fibular head, particularly at the fibrous opening of the peroneus longus muscle. Rapid weight loss may transiently increase risk for ischemic stroke events. As the incidence of medication-assisted rapid weight loss increases, this case underscores the importance of considering both central and peripheral causes of foot drop.

Conclusions: Suspicion for neuropathy symptoms is warranted following significant weight loss, as it is an important risk factor for peroneal neuropathy. Electromyography is valuable for both diagnosis and monitoring recovery. Conservative management with bracing and physical therapy should be initiated, but surgical decompression may be necessary, followed by a structured rehabilitation program to achieve optimal outcomes.