PURPOSE: To demonstrate which structures of the extensor mechanism create a boutonniere deformity, when damaged, in a cadaver model. An analysis of how damage to these anatomical structures affects the biomechanical performance of the extensor mechanism was also performed.

METHODS: We secured 18 fresh cadaveric hands onto an apparatus consisting of a computer-controlled motor and tensiometer attached in series to the extensor communis tendon of the ring and middle digits. The central ...

The complex yet delicate anatomy of the hand allows for the array of functions it can accomplish. The coupled forces of flexion and extension with respect to each joint keep the digits in balance. To comprehend the sophisticated functions of the extensor tendons, one must have a clear appreciation for both the myriad of anatomical variations described in the literature and the dynamic forces occurring within this physical system. With an awareness of the possible aberrations and an ...