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Hand & Upper Limb
intermediate
X-Type

Anterior Interosseous Nerve - Anatomy and Clinical Syndromes

Nerve Anatomy

A 42-year-old man presents with inability to make an "OK" sign with his thumb and index finger. He has no sensory loss in the hand. Examination shows weakness of thumb IP flexion and index finger DIP flexion. The surgeon suspects anterior interosseous nerve (AIN) syndrome and discusses the anatomy and clinical features with the registrar. Regarding the anterior interosseous nerve:

Mark each as TRUE or FALSE

A

The AIN is a pure motor branch of the median nerve that supplies three muscles: flexor pollicis long...

B

Kiloh-Nevin syndrome (AIN palsy) presents with inability to make a proper "OK" sign producing a tear...

C

Martin-Gruber anastomosis is a crossover from ulnar to median nerve in the forearm; AIN syndrome alw...

D

Martin-Gruber anastomosis is a crossover from median (AIN) to ulnar nerve in the forearm present in ...

E

Parsonage-Turner syndrome (neuralgic amyotrophy) can mimic AIN palsy and is characterized by severe ...

Answer the questions to see explanations

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