Anatomy of the finger flexor tendon sheath and pulley system.

Additions and changes in the description of the anatomy of the finger flexor sheath and pulleys that I published in 1974 and 1975 have prompted me to restudy this system. Sixty-one fresh human cadaver fingers were dissected using the operating room microscope. This study demonstrated a flexor synovial sheath composed of visceral and parietal elements from the neck of the metacarpal to the distal interphalangeal joint, which was overlaid with a series of retinacular structures (pulleys). The pulleys identified were the palmar aponeurosis pulley, five annular pulleys, and three cruciform pulleys. Although significant variations were noted in the morphology of the first annular and the cruciform pulleys sufficient similarity exists between my first description and the present study to support the use of the original descriptive terminology. A significant addition to the pulley system is the palmar aponeurosis pulley described by Manske and Lesker.