Skeletal muscle diseases — Flashcards

Flashcard 1: _____ muscular dystrophy typically presents before 5 years of age

Answer: Duchenne

Flashcard 2: _____ is a malignant tumor of skeletal muscle

Answer: Rhabdomyosarcoma

Flashcard 3: _____ is a trinucleotide repeat disorder that causes degeneration of the cerebellum and multiple spinal cord tracts

Answer: Friedreich ataxia

Flashcard 4: What type of hypersensitivity reaction is Graves disease and Myasthenia Gravis? _____

Answer: Type II HSR (cellular dysfunction)

Flashcard 5: What musculoskeletal disorder is characterized by metaplasia of skeletal muscle fibroblasts to bone? _____

Answer: Myositis ossificans

Flashcard 6: Loss of dystrophin (e.g. X-linked muscular dystrophy) results in myo-_____

Answer: necrosis

Flashcard 7: What is the term for infarcted tissue in the basal ganglia or internal capsule caused by occlusion of a lenticulostriate artery?

Answer: lacunar infarct

Flashcard 8: epidural hematoma

Answer: rupture of middle meningeal artery; fracture of temporal bone

Extra: rapid arterial bleedinglucid interval followed by decreased LOC; CN 3 palsy, increased ICPCT: biconvex, hyperdense blood; does not cross sutures; may cross falx, tentorium 

Flashcard 9: What is the cause of central pontine myelinolysis?

Answer: Often iatrogenic; caused by rapid correction of chronic hyponatremia.

Extra: - Pathogenesis: Massive axonal demyelination of pontine white matter tracts. - Clinical Features: Acute paralysis, dysarthria, dysphagia, diplopia, loss of consciousness; may progress to locked-in syndrome. - MRI (T2): Increased signal (hyperintensity) in the central pons. - Mnemonic: "From Low to High (Sodrum), your Pons will Die."

Flashcard 10: Which vessel is ruptured in a Subdural Hematoma?

Answer: Bridging veins rupture (crescent-shaped on CT)

Extra: Mechanism: Slow venous bleeding via rupture of bridging veins. Clinical: Decreased LOC, increased ICP. CT findings: Crescent-shaped, hyperdense blood (in acute phase); crosses suture lines; does not cross dural attachments (falx, tentorium). Risk factors: Brain atrophy, elderly, alcoholics, shaken baby syndrome.