This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2018, Subject name: Orthopaedics
A patient of supracondylar humerus fracture is unable to flex interphalangeal joint of the thumb. Which nerve is most likely injured? 
Select and explain. 
A. Median nerve, B. Superficial branch of ulnar nerve, C. AIN, D. Pin
C: AIN
Answer: C: AIN 
Explanation: Flexion of interphalangeal joint of thumb is carried out by flexor pollicis longus. It is supplied by AIN, a branch of median nerve. Muscles which are supplied by AIN are flexor digitorum profundus (Lateral 1/2 ), flexor pollicis longus and pronator quadratus. PIN a branch of radial nerve causes finger drop Supra condylar fracture of Humerus - Order of nerve involvement in children:AIN > Median Nerve > Radial Nerve > Ulnar Nerve