Arterial blood supply of the extensor apparatus of the long fingers

Background: The extensor apparatus vascularization is less studied compared with flexor tendons. The aim of the present anatomical work was to study it in a more systematic way and find clinical applications. Methods: The study was carried on 40 fingers from 10 fresh cadaver hands. Two catheters (16 gauge) were introduced into the radial and ulnar arteries on the volar side of the wrist. Acetone was used for arterial cleaning and color latex for the arterial system coloration. The authors proceeded with the dissections, always in the same manner: they first made the longitudinal dorsal incisions from the metacarpophalangeal to distal interphalangeal joints. Raising the skin, they identified the thin subcutaneous branches into the hypodermal plane; they followed their course until their origin, which allowed identification of the arterial branches of the extensor apparatus. For measurements, they used as a point of reference the emergence distance of those dorsal branches from the metacarpophalangeal and proximal and distal interphalangeal joints. Results: The extensor apparatus vascularization was segmental, realized through the paratenon from the branches of a vascular cutano-tendino-osseous complex through a common trunk, issued from the propria digital artery. This complex nourished not only the extensor apparatus but also the dorsal digital skin and periosteum. Its location was consistent at the level of both proximal and middle phalanges. Conclusions: This consistency explains the anatomical basis for the realization of composite-free tissue transfer in cases of banked fingers. The osteotomies could be performed at well-defined distances from the joints.