PURPOSE: The purpose of this study was to determine biomechanically the relative contributions of the dorsal and palmar capsuloligamentous structures to dorsal and palmar carpal stability. METHODS: Seven fresh-frozen cadaver specimens were tested using a testing machine (MTS, Eden Prairie, MN) with low loads applied perpendicular to the axis of the radial diaphysis. We determined the loads required to achieve dorsal and palmar translation of the carpus on the radius as palmar and dorsal ligaments and capsule were sectioned sequentially. The relative contributions of the dorsal and palmar capsuloligamentous structures to dorsal and palmar stability were determined. RESULTS: The palmar structures provided a statistically significantly greater restraint (61%) to dorsal translation of the carpus than did the dorsal structures (2%). The palmar structures also provided a statistically greater restraint (48%) to palmar translation of the carpus than did the dorsal structures (6%). CONCLUSIONS: The palmar capsuloligamentous structures provided greater restraint to both dorsal and palmar translation of the carpus. We suggest that surgeons consider repair or reconstruction of traumatic injuries to these structures.
PURPOSE: The purpose of this study was to determine biomechanically the relative contributions of the dorsal and palmar capsuloligamentous structures to dorsal and palmar carpal stability. METHODS: Seven fresh-frozen cadaver specimens were tested using a testing machine (MTS, Eden Prairie, MN) with low loads applied perpendicular to the axis of the radial diaphysis. We determined the loads required to achieve dorsal and palmar translation of the carpus on the radius as palmar and dorsal ligaments and capsule were sectioned sequentially. The relative contributions of the dorsal and palmar capsuloligamentous structures to dorsal and palmar stability were determined. RESULTS: The palmar structures provided a statistically significantly greater restraint (61%) to dorsal translation of the carpus than did the dorsal structures (2%). The palmar structures also provided a statistically greater restraint (48%) to palmar translation of the carpus than did the dorsal structures (6%). CONCLUSIONS: The palmar capsuloligamentous structures provided greater restraint to both dorsal and palmar translation of the carpus. We suggest that surgeons consider repair or reconstruction of traumatic injuries to these structures.