[Vascular supply of the unsheathed segment of the extensor tendons of the 2d to 5th fingers of the dorsum of the hand].

The dorsal approach to the metacarpal bones is through the peritendinous connective tissue of the extensor tendons. Knowledge of the vascular supply of the distal parts of these tendons, between the distal end of the tendon sheath and the tendon's osseous insertion is important, especially with respect to atraumatic technique. The course and distribution of the vessels to the extensor tendons II-V were investigated. Superficial and deep layers of connective tissue were found to contain blood vessels. The superficial vessels reach the dorsal aspect of the extensor tendon, originating from subcutaneous arteries and the large arteries of the hand. The deep vessels reach the lateropalmar aspect of the tendons and originate from the peritendinous muscular arteries. Vessel distribution suggests a direct relationship between the number of nourishing arteries and the tendon surface area. The vascular supply to the unsheathed parts of the extensor tendons shows morphological adaptations to differential mechanical stress during tendon excursion.