The Base Of The Distal Phalanx In Posterior View

Description

Rotating in a posterior (dorsal) view, the animation isolates the base of a distal phalanx of the hand and clarifies its relationship to the shaft distally and the distal interphalangeal (DIP) joint surface proximally. Along the dorsal margin at the proximal end, a low transverse ridge becomes apparent as the light and camera angle shift, separating the articular region from the nonarticular dorsal cortex. The contour transitions from the broader proximal base to the narrower distal body, keeping medial and lateral edges readable as the bone turns. For teaching DIP joint mechanics and extensor apparatus anatomy, that dorsal ridge is a useful landmark because the terminal extensor tendon inserts onto the dorsal base of the distal phalanx. This is where mallet finger injuries concentrate, when forced flexion of an extended DIP joint avulses a bony fragment from the dorsal base or ruptures the tendon, and the sequential rotation helps viewers appreciate why small avulsion fragments can be hard to interpret on a single radiographic projection. Surface orientation matters here. Subtle changes in dorsal profile can influence fracture classification and operative planning when a dorsal avulsion involves a large portion of the articular surface. Use this animation in gross anatomy and hand surgery teaching sessions to orient learners to the distal phalanx base before correlating with lateral finger radiographs, ultrasound of the extensor tendon insertion, or intraoperative fluoroscopy during DIP pinning. It also fits orthopedic and emergency medicine modules covering distal phalanx fractures, mallet finger, and dorsal avulsion patterns in the hand skeleton. Anatomical accuracy verified by SciePro's Medical Advisory Board.