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Basic Science
intermediate
X-Type

Radial Nerve Anatomy - Spiral Groove, PIN, and Superficial Branch

Upper Limb Neuroanatomy

A 45-year-old man presents with wrist drop after falling asleep with his arm over a chair back while intoxicated. He cannot extend his wrist, fingers, or thumb. He has sensory loss over the dorsal first web space. The brachioradialis reflex is absent. Regarding the anatomy of the radial nerve:

Mark each as TRUE or FALSE

A

The radial nerve arises from the posterior cord of the brachial plexus (C5-T1); it enters the arm po...

B

In the spiral groove, the radial nerve lies in direct contact with the humeral shaft for approximate...

C

The radial nerve supplies all muscles of the anterior compartment of the forearm; it is the only ner...

D

In the arm, the radial nerve innervates triceps (all three heads), anconeus, brachioradialis, and ex...

E

Spiral groove palsy (Saturday night palsy) presents with wrist drop and finger/thumb drop, but trice...

Answer the questions to see explanations

Click T (True) or F (False) for each option