title: Arm Abduction Provides a Better Reduction of the Bankart Lesion During Immobilization in External Rotation After an Initial Shoulder Dislocation.
abstract: BACKGROUND
  Shoulder dislocation often recurs, especially in the younger population. Immobilization in external rotation, in which a Bankart lesion is displaced in the anterior, medial, and inferior directions, was introduced as a new method of nonoperative treatment, but its clinical efficiency is controversial. In terms of reducing the lesion, it is reasonable to incorporate not only external rotation, which makes the anterior soft tissues tight to push the lesion posteriorly and laterally, but also abduction, which makes the inferior soft tissues tight to push the lesion superiorly.
  
  
  OBJECTIVE
  Abducting the arm during immobilization in external rotation will improve the reduction of a Bankart lesion.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  There were 37 patients with initial shoulder dislocation enrolled in this study. After reduction, MRI was taken in 4 positions of the shoulder: adduction and internal rotation (Add-IR), adduction and external rotation (Add-ER), 30° of abduction and 30° of external rotation (Abd-30ER), and 30° of abduction and 60° of external rotation (Abd-60ER). On radial slices, the separation, displacement of the labrum, and opening angle of the capsule were measured.
  
  
  RESULTS
  Add-ER improved the reduction of the anterior labrum but not the inferior labrum when compared with Add-IR. Both Abd-30ER and Abd-60ER improved the reduction of the inferior labrum as compared with Add-IR. Furthermore, Abd-60ER improved the reduction more than Add-ER.
  
  
  CONCLUSIONS
  Among the 4 positions tested, Abd-60ER is the best position in terms of reducing the Bankart lesion.
  
  
  CONCLUSIONS
  Abducting the shoulder during immobilization in external rotation is demonstrated to improve the reduction of the Bankart lesion. Therefore, this position is expected to reduce the recurrence rate after initial dislocation of the shoulder. Future clinical trials are necessary.
authors: Tohoku University School of Medicine, Sendai, Japan itoi-eiji@med.tohoku.ac.jp.
authors: Eiji
authors: E
authors: Itoi
authors: Kumamoto Orthopaedic Hospital, Kumamoto, Japan.
authors: Toshio
authors: T
authors: Kitamura
authors: Tohoku University School of Medicine, Sendai, Japan.
authors: Shin
authors: S
authors: Hitachi
authors: Tohoku University School of Medicine, Sendai, Japan.
authors: Taku
authors: T
authors: Hatta
authors: Tohoku University School of Medicine, Sendai, Japan.
authors: Nobuyuki
authors: N
authors: Yamamoto
authors: Sendai City Hospital, Sendai, Japan.
authors: Hirotaka
authors: H
authors: Sano
mesh_terms: D000293:Adolescent; D000328:Adult; D001132:Arm / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012008:Recurrence; D012399:Rotation; D012783:Shoulder Dislocation / Q000628:therapy*; D055815:Young Adult
keywords: Bankart lesion; abduction; capsulolabral complex; external rotation; immobilization; shoulder dislocation