Fourteen cadaveric wrists were dissected to investigate a modified dorsal approach that involved osteotomy of the small and dorsal tubercles without opening the third compartment. This approach could be safely made with good exposure of the dorsum of the wrist. The mean normal angle formed by the extensor pollicis longus tendon at the level of the dorsal tubercle was 144°. An approach that involves division of the third compartment may lead to effective lengthening of the extensor pollicis longus musculotendinous unit by 8 to 17 mm with corresponding decrease in the tension generated by its contraction. The modified approach permits restoration of the normal alignment of the extensor pollicis longus tendon, and may be useful for performing arthrodesis of the non-rheumatoid wrist in young manual workers.
