March 13th, 2004
AOSSM Specialty Day

Immobilization in External Rotation after Shoulder Dislocation: An Interim Report of an Ongoing Trial

Authors:
  1. Eiji Itoi MD, Akita University School of Medicine, Akita, Japan
  2. Yuji Hatakeyama, Nakadori General Hospital, Akita, Japan
  3. Takeshi Sato, Honjo Daiichi Hospital, Honjo, Japan
  4. Tadato Kido, Tazawako Municipal Hospital, Tazawako, Japan
  5. Hiroshi Minagawa, Akita University School of Medicine, Akita, Japan
  6. Ikuko Wakabayashi, Akita City Hospital, Akita, Japan
  7. Moto Kobayashi, Akita University School of Medicine, Akita, Japan
  8. Hidetomo Saito, Akita University School of Medicine, Akita, Japan
Objective:  Recurrent dislocations have been reported in 66 percent to 94 percent of young patients after immobilization of the shoulder in internal rotation. Based on the previous studies that illustrated the benefits of external rotation both in cadavers and on MRI, we began a prospective study. Our early findings demonstrated that patients immobilized in external rotation avoided recurrent dislocations. The present study reports further results of this ongoing prospective multicenter study.
Methods:  Since January 2000, 96 patients with anterior dislocation of the shoulder were randomly assigned to immobilization in either internal rotation (IR group) or external rotation (ER group) for 3 weeks. After excluding patients with humeral fractures, and those whose shoulders were not immobilized within 3 days after injury, 80 patients were left for analyses. Sixty-four shoulders were initial dislocations and 16 were recurrent dislocations. There were 40 patients in each group (average age 37 yrs). The average follow-up period was 12.4 months.
Results:  The average immobilization period was 15.9 } 8.1 days in the IR group and 16.9 } 7.1 days in the ER group. Recurrence rate was 12/40 (30 percent) in the IR group and 4/40 (10 percent) in the ER group (p=0.0255). Among those who were younger than 29 years of age, recurrence rate was 9/24 (37.5 percent) in the IR group and 3/26 (11.5 percent) in the ER group (p=0.0319).
Conclusions:  Immobilization in external rotation after shoulder dislocation is better than the conventional immobilization in internal rotation in terms of reducing recurrent dislocations.
References:  
  1. Itoi E, et al. Position of immobilization after dislocation of the shoulder: a cadaveric study. J Bone Joint Surg [Am] 1999; 81: 385-390.
  2. Itoi E, et al. Position of immobilization after dislocation of the glenohumeral joint: a study with use of magnetic resonance imaging. J Bone Joint Surg Am 2001; 83: 661-7.
Acknowledgements:  
Keywords:
  1. Ligament
 Categories:
  1. CLINICAL: Shoulder - Anterior Instability