The Hip: Preservation, Replacement and Revision

External Rotation of Knee Joint



- See: Internal Rotation

- Discussion:
    - external-rotation laxity increases w/ knee flexion, w/ largest amount (20 degrees) being seen in the 30-40-deg range of flexion;
    - external rotation is not directly limited by cruciate ligaments;
    - only PCL, which becomes taut at 90 deg of flexion, would be expected to provide restraint should posterolateral structures be injured;
    - external-rotation laxity is markedly increased only when posterolateral structures or LCL, or both, are cut;
    - concomitant loss of PCL results in greater increases in rotation laxity



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, August 30, 2011 3:33 pm