Should acute anterior dislocations of the shoulder be immobilized in external rotation? A cadaveric study.
The high recurrence rate associated with anterior shoulder dislocations may reflect inadequate healing of a Bankart lesion when the arm is immobilized in internal rotation. The effect of external rotation (ER) of the humerus on the glenoid-labrum contact of Bankart lesions was examined in 10 human cadaveric shoulders. The contact force between the glenoid labrum and the glenoid was measured in 60 degrees of internal rotation, neutral rotation, and 45 degrees of ER in 10 human cadaveric shoulders. No detectable contact force was found with the arm in internal rotation. The contact force increased as the arm passed through neutral rotation and reached a maximum at 45 degrees of ER. The contact force returned to 0 g when the arm was returned to neutral rotation. The mean contact force at 45 degrees of ER was 83.5 g. External rotation significantly increases the labrum-glenoid contact force and may influence the healing of a Bankart lesion.
Miller
Bruce S
BS
Orthopaedic Research Laboratories, Division of Surgery, University of New South Wales, Prince of Wales Hospital, Sydney, Australia 2031.
Sonnabend
David H
DH
Hatrick
Cameron
C
O'leary
Sean
S
Goldberg
Jerome
J
Harper
Wade
W
Walsh
William R
WR
D000208:Acute Disease; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D006801:Humans; D007103:Immobilization; D008297:Male; D008875:Middle Aged; D011187:Posture; D016059:Range of Motion, Articular; D018570:Risk Assessment; D012399:Rotation; D012680:Sensitivity and Specificity; D012783:Shoulder Dislocation / Q000628:therapy*