Human Male Thumb Anatomy, Posterior View

Description

Dorsally, the male thumb (pollex) is presented from a posterior hand perspective, with the nail plate and dorsal skin overlying the distal and proximal phalanges and the first metacarpal. The interphalangeal joint lies distal to the metacarpophalangeal joint, and the first carpometacarpal articulation sits proximally where the base of the first metacarpal meets the trapezium. Along the dorsolateral contour, the extensor pollicis longus tendon courses toward the distal phalanx while extensor pollicis brevis tracks to the base of the proximal phalanx, defining the dorsal thumb profile. Key bony landmarks align in a proximal to distal sequence: first metacarpal shaft, head, proximal phalanx, and distal phalanx. A posterior view of the thumb matters because extensor tendon position and joint alignment are what you assess when extension is lost after laceration, crush injury, or postoperative stiffness. Clinical teaching often centers on the extensor pollicis longus because it can rupture after distal radius fractures, producing an inability to extend the interphalangeal joint even when the thumb remains stable at the metacarpophalangeal level. This angle also supports discussion of dorsal MCP collateral injury and mallet-type injuries of the thumb, where the terminal extensor mechanism at the distal phalanx becomes the focus. Use this artwork for upper limb anatomy modules, hand therapy education, and surgical or emergency medicine publications explaining dorsal thumb tendon anatomy, tendon repair zones, or exam findings for extensor pollicis longus and extensor pollicis brevis integrity. Anatomical accuracy verified by SciePro's Medical Advisory Board.