Radial head subluxation (nursemaid's elbow) is characterized by all the following EXCEPT

Correct Answer: C

Rationale: Radiographs are not typically needed for nursemaid's elbow as it's a clinical diagnosis reducible without imaging.

Correct Answer: A

Rationale: Hypokalemia causes episodic paralysis due to potassium shifts affecting muscle function. Other conditions don't feature episodic paralysis.

Correct Answer: D

Rationale: Kearns-Sayre syndrome (mitochondrial disorder) features external ophthalmoplegia. Other conditions don't affect eye muscles this way.

Correct Answer: D

Rationale: All (cardiomyopathy, intellectual impairment, respiratory weakness, scoliosis) are characteristic of Duchenne muscular dystrophy, so E (moved to D) is correct.

Correct Answer: D

Rationale: Myasthenia gravis is primarily an autoimmune disorder (antibodies against acetylcholine receptors), not inherited or purely postinfectious.