Posterior Perspective of the Hand Muscles

Description

Dorsally, the extensor tendons form prominent longitudinal bands over the metacarpals and proximal phalanges, continuing distally into the extensor expansions on digits II to V. Between these tendon slips, the dorsal interossei occupy the intermetacarpal spaces, lying deep to the extensor apparatus and spreading laterally toward the proximal phalanges and extensor hoods. Proximally at the wrist, the extensor retinaculum spans transversely, with tendons of extensor digitorum, extensor indicis, and extensor digiti minimi tracking into the hand in parallel. Thenar and hypothenar muscle masses are referenced as regional landmarks at the radial and ulnar borders, even though their bulk is primarily palmar. A dorsal perspective matters when you need to teach or plan around the extensor mechanism, where small disruptions can produce disproportionate functional loss. Sagittal band rupture at the metacarpophalangeal joint, classic in rheumatoid arthritis or after a direct blow, allows extensor tendon subluxation and impaired active extension. Finger lacerations over the dorsum also map cleanly to extensor tendon zones and guide repair strategy, splinting position, and expectations for postoperative stiffness. Use this illustration in gross anatomy and upper-limb dissection labs to orient students to the layered relationship of dorsal interossei, extensor tendons, and the extensor hood. It also fits operative notes, hand therapy manuals, and patient education for extensor tendon repair, boutonniere and mallet injury mechanisms, and dorsal hand compartment anatomy at the wrist. Anatomical accuracy verified by SciePro's Medical Advisory Board.