Adult Male Thumb, Anterior View

Description

Anterior anatomy of the adult male pollex is presented from the palmar side, with the distal phalanx and proximal phalanx aligned on the first metacarpal and oriented lateral to the thenar eminence. The interphalangeal crease and metacarpophalangeal region define the transition points where the flexor pollicis longus tendon traverses volarly toward its distal insertion. Radially, the abductor pollicis brevis and opponens pollicis form the bulk of the thenar contour, while the adductor pollicis lies deeper on the ulnar side of the first metacarpal, drawing the thumb toward the index ray. Skin and subcutaneous tissue are thin over the phalanges and thicker over the thenar pad. Palmar thumb anatomy matters because small changes in tendon glide and joint alignment translate into large functional loss during pinch and opposition. This view is a practical reference for understanding trigger thumb, where stenosing tenosynovitis at the A1 pulley causes painful catching at the metacarpophalangeal level, and for distinguishing it from interphalangeal joint pathology. It also supports surgical planning for thenar and volar approaches, where protecting the superficial palmar branch of the radial artery and the digital neurovascular bundles is non-negotiable. Pinch mechanics live here. Use this artwork in gross anatomy and hand surgery teaching files to anchor discussions of thumb flexion, opposition, and key pinch, or in medical publishing diagrams on trigger thumb release, volar lacerations, and tendon repair zones of the digit. Anatomical accuracy verified by SciePro's Medical Advisory Board.