Single-incision extensile volar approach to the distal radius and concurrent carpal tunnel release: cadaveric study.

PURPOSE: To determine whether a single-incision extensile approach to the distal radius used for open reduction internal fixation and a concomitant radial sided carpal tunnel (CT) release safely and effectively decompresses the carpal tunnel.

METHODS: Five pairs of cadaveric forearms were mounted to a tabletop with a cable pulley system attached to the long finger. Each paired specimen was randomized to volar plating via either the flexor carpi radialis approach (control group) or the extensile volar exposure (combined flexor carpi radialis and radial-sided carpal tunnel release). Before and after the respective exposure and plating, increased CT pressures were created with 2.27, 4.54, and 6.81 kg of distraction. We used a paired t-test to compare the change in CT pressure at each level of distraction before and after intervention for the 2 groups, with significance set at p </= .05. A dissection of each exposure was performed with attention given to the radial aspect of the transverse carpal ligament (TCL) and any possible iatrogenic injuries.

RESULTS: Carpal tunnel pressure increased with increasing distraction. We noted a statistically significant reduction in CT pressure after the extensile exposure and plating with 4.54 (p = .023) and 6.81 (p < .001) kg of distraction, respectively. No significant reduction in mean CT pressure for the control group specimens occurred at any level of distraction force. The average length of the radial TCL was 22 mm (range, 18-31 mm); the average distance between the recurrent motor branch and distal TCL was 11 mm (range, 8-15 mm). No iatrogenic tendon or nerve injury occurred with the extensile volar exposure.

CONCLUSIONS: Carpal tunnel pressure is safely reduced and the distal radius is adequately exposed for fixation with the extensile volar approach.