title: Rotational stability of the carpus relative to the forearm.
abstract: To perform rotational tasks adequately, the rotational laxity between the radius and the carpus must be constrained within a certain limit. The contribution of nine individual capsuloligamentous structures to the rotational stability of the radiocarpal joint was studied using 14 fresh-frozen human cadaveric specimens. Torque-rotation curves, with sequential section of the soft-tissue structures, were used to calculate the percentage contribution of each individual structure. The primary pronation constraint was the palmar radioscaphocapitate ligament. The contributions to supination constraint were more complex; the dorsal radiotriquetral ligament was dominant, assisted by the palmar ulnolunate ligament. Structures originating from the ulna changed their major constraint contribution with forearm orientation, whereas those with a radial origin had a constant contribution independent of forearm rotation. Injury of these structures may lead to rotational instability at the radiocarpal level and should be considered when treating carpal instabilities.
authors.affiliation: Department of Orthopedics, Mayo Clinic/Mayo Foundation, Rochester, MN 55905, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Ritt
authors.forename: P R
authors.initials: PR
authors.lastname: Stuart
authors.forename: L J
authors.initials: LJ
authors.lastname: Berglund
authors.forename: R L
authors.initials: RL
authors.lastname: Linscheid
authors.forename: W P
authors.initials: WP
authors.lastname: Cooney
authors.forename: K N
authors.initials: KN
authors.lastname: An
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D005542:Forearm / Q000502:physiology*; D006801:Humans; D066298:In Vitro Techniques; D007593:Joint Instability / Q000503:physiopathology; D008023:Ligaments, Articular / Q000502:physiology; D008297:Male; D008875:Middle Aged; D011403:Pronation / Q000502:physiology; D012399:Rotation; D013484:Supination / Q000502:physiology; D014955:Wrist Joint / Q000502:physiology*