Pressure Changes in the Carpal Tunnel with Movement of the Pisiform Bone

Seven fresh cadaveric forearms were studied to investigate the effects of medial and lateral positioning of the pisiform bone on pressure within the carpal tunnel. The wick catheter, a device used to transmit interstitial fluid pressure, was inserted into the carpal tunnels of the cadavers. Pressures in the tunnel with the pisiform in a resting position, medial position, and lateral position were measured via a water manometer. A significant increase in pressure was noted between the resting position and both the medial and lateral positions (p = 0.001). No significant difference was found between the medial and lateral positions (p > 0.05). Findings suggest that the use of movement of the pisiform as a conservative treatment in carpal tunnel syndrome is questionable.