Anatomical Study of the First Dorsal Interosseous Tendon for its Use as a Plasty of the Radial Collateral Ligament of the Index Metacarpophalangeal Joint

Abstract

Purpose The authors present an anatomical study to justify the use of the distal portion of the tendon of the first dorsal interosseous muscle (FDIM) for the repair of the chronic rupture of the radial collateral ligament (RCL) of the metacarpophalangeal joint of the index finger. Methods Ten hands of cryopreserved specimens were used and thawed at room temperature for dissection with optical magnification. Five were hands of women, and their ages ranged from 46–96 years (mean: 72.8), and 8 corresponded to the right hand. Results The length of the tendon of the FDIM ranged from 20 to 40 mm (mean: 25 mm). The length of the RCL ranged from 14 to 24 mm (mean: 18.2 mm). The difference between both structures of the same specimen averaged 6.8 mm (2–16 mm). Therefore, the dorsal portion of the tendon of the FIDM is always at least 2 mm longer than the length of the RCL. Conclusions In conclusion, this is a simple technique that allows the surgeon to perform a plasty of the RCL without sacrificing another tendon in the absence of the palmaris longus, which is more commonly used for this purpose. The maintenance of its distal insertion may also help in the revascularization of the repaired area.