Peripheral Neuroanatomy, Human Anatomy, USMLE Step 1 - Full Vignette with Extended Explanations скачать в хорошем качестве

Peripheral Neuroanatomy, Human Anatomy, USMLE Step 1 - Full Vignette with Extended Explanations

A 54-year-old man develops right-sided foot slapping, weakness, and numbness over the outer leg and dorsum of the foot after squatting outdoors in hot weather. He has a complex medical history and examination reveals localized neurologic deficits, with preserved upper-extremity strength. What anatomic considerations and bedside findings are most important for localizing this patient s lesion and guiding urgent management? VIDEO INFO Category: Peripheral Neuroanatomy, Human Anatomy, USMLE Step 1 Difficulty: Hard - Advanced level - Challenges experienced practitioners Question Type: Differential Physical History Case Type: ED Case Explore more ways to learn on this and other topics by going to https://endlessmedical.academy/auth?h... QUESTION A 54-year-old man presents to a United States emergency department in midsummer after working outdoors laying sod in humid heat. He reports generalized fatigue and cramps earlier in the day and now new right-sided foot slapping and lateral leg numbness that began after a prolonged squat while installing edging stones. On arrival, temperature is 41.2 degreesC (active cooling initiated), pulse 120/min, respiratory rate 17/min, blood pressure 147/101 mm Hg, and oxygen saturation 96% on room air.... OPTIONS A. Common peroneal (fibular) nerve compression at the fibular neck (fibular tunnel) producing foot drop with dorsiflexion and eversion weakness, preserved inversion, sensory loss over the dorsum of the foot and lateral shin, normal plantar sensation, symmetric reflexes, focal fibular-neck tenderness... B. Common fibular division neuropathy of the sciatic nerve within the popliteal fossa causing foot drop with similar dorsiflexion and eversion weakness but typically lacking focal fibular-neck tenderness and more often showing short head of biceps femoris involvement on electrodiagnostics rather tha... C. L5 radiculopathy from foraminal stenosis presenting with foot drop that also weakens ankle inversion and sometimes hip abduction, often with dermatomal back-to-leg pain, root tension signs, and reflex asymmetry rather than isolated dorsum-of-foot numbness with preserved plantar sensation. D. Deep peroneal nerve entrapment at the anterior tarsal tunnel presenting with first-web-space sensory loss and toe extensor weakness limited to distal muscles, with preserved eversion, no focal findings at the fibular neck, and no lateral-leg sensory deficit. CORRECT ANSWER A. Common peroneal (fibular) nerve compression at the fibular neck (fibular tunnel) producing foot drop with dorsiflexion and eversion weakness, preserved inversion, sensory loss over the dorsum of the foot and lateral shin, normal plantar sensation, symmetric reflexes, focal fibular-neck tenderness, and a positive Tinel sign after prolonged squatting. EXPLANATION "Common peroneal (fibular) nerve compression at the fibular neck (fibular tunnel) producing foot drop with dorsiflexion and eversion weakness, preserved inversion, sensory loss over the dorsum of the foot and lateral shin, normal plantar sensation, symmetric reflexes, focal fibular-neck tenderness, and a positive Tinel sign after prolonged squatting." This localization fits the bedside pattern. The common peroneal nerve wraps superficially around the fibular neck, making it vulnerable to compression from leg-crossing, squatting, weight loss, and external pressure.... --------------------------------------------------- Our cases and questions come from the https://EndlessMedical.Academy quiz engine - multi-model platform. Each question and explanation is forged by consensus between multiple top AI models (GPT, Claude, Grok, etc.), with automated web searches for the latest research and verified references. Calculations (e.g. eGFR, dosages) are checked via code execution to eliminate errors, and all references are reviewed by several AIs to minimize hallucinations. Important note: This material is entirely AI-generated and has not been verified by human experts; despite stringent consensus checks, perfect accuracy cannot be guaranteed. Exercise caution - always corroborate the content with trusted references or qualified professionals, and never apply information from this book to patient care or clinical decisions without independent verification. Clinicians already rely on AI and online tools - myself included - so treat this book as an additional focused aid, not a replacement for proper medical education. Visit https://endlessmedical.academy for more AI-supported resources and cases. This material can not be treated as medical advice. May contain errors. ---------------------------------------------------