The ape-thumb deformity occurs due to lesion of: (A) Radial nerve, (B) Median nerve, (C) Ulnar nerve, (D) Musculocutaneous nerve
Answer is B. Injury to the median nerve at the wrist is much more common than at the elbow. This is due to the superficial position of the nerve at this site.It produces Ape thumb deformity where the thenar muscles are wasted, and the thumb is adducted and laterally rotated.Ref: BD Chaurasia; volume 1; 6th edition