HOME HELP CONTACT US SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:
Sign In to gain access to subscriptions and/or personal tools.

This Article Full Text Full Text (PDF) All Versions of this Article: 36/6/1123    most recent 0363546508314391v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Request Reprints Google Scholar Articles by Mologne, T. S. Articles by Provencher, M. T. PubMed PubMed Citation Articles by Mologne, T. S. Articles by Provencher, M. T. Related Collections Biomechanics Shoulder Arthroscopy

The Addition of Rotator Interval Closure After Arthroscopic Repair of Either Anterior or Posterior Shoulder Instability

Effect on Glenohumeral Translation and Range of Motion

Timothy S. Mologne, MD, Kristin Zhao, MA, Michio Hongo, MD, PhD, Anthony A. Romeo, MD, Kai-Nan An, PhD and Matthew T. Provencher, MD, LCDR, MC, USNR^||,¶

From the Sports Medicine Center, Appleton, Wisconsin, the Biomechanics Laboratory, Division of Orthopaedic Research, Mayo Clinic, Rochester, Minnesota, Department of Orthopaedic Surgery, Division of Orthopaedic Sports Medicine, Rush University, Chicago, Illinois, and the ^|| Naval Medical Center, Department of Orthopaedic Surgery, San Diego, California

^¶ Address correspondence to Matthew T. Provencher, MD, Naval Medical Center San Diego, Division of Orthopaedic Shoulder & Sports Surgery, Department of Orthopaedic Surgery, 34800 Bob Wilson Drive, Suite 112, San Diego, CA 92134-1112 (e-mail: matthew.provencher{at}med.navy.mil).

Background: Although the use of rotator interval closure is frequently advocated as a useful supplement to shoulder instability repairs, the addition of a rotator interval closure after arthroscopic instability repair has not been fully investigated.

Purpose: The objective of this study was to investigate whether a rotator interval closure improves glenohumeral stability in an anterior and posterior instability shoulder model.

Study Design: Controlled laboratory study.

Methods: Fourteen fresh-frozen cadaveric shoulder specimens were dissected free of soft tissues, leaving the rotator cuff intact with simulated cuff loading. All specimens were mounted in a custom testing apparatus using infrared sensors to document glenohumeral translation and rotation. The specimens were then tested for stability in the following order: vented/subluxated state, after arthroscopic anterior (Group 1; 7 specimens) or posterior (Group 2; 7 specimens) instability repair with suture anchors, and then after rotator interval closure. For each of the 3 testing conditions, the following were measured: (1) external and internal rotation at neutral, (2) external and internal rotation at 90° of abduction, (3) posterior and anterior translation at neutral rotation (15 N and 25 N), (4) anterior translation at 90° of abduction and external rotation (Group 1; 15 N and 25 N), (5) posterior translation at 90° of flexion and internal rotation (Group 2; 15 N and 25 N), and (6) sulcus testing in neutral (7.5 N).

Results: Posterior stability was only improved after anchor capsulolabral repair (8.0 to 5.0 mm; P = .017, 25 N), but there was no improvement after rotator interval closure (5.0 to 4.6 mm; P = .453). However, anterior stability was improved after capsulo-labral repair (8.6 to 4.0 mm; P = .016, 25 N) and also improved further by rotator interval closure (4.0 to 2.4 mm; P = .007). The mean loss of external rotation was significantly increased by the addition of the rotator interval closure in both neutral and abducted glenohumeral positions, with a mean external rotation loss of 28° in neutral (P = .013). The addition of a rotator interval closure did not improve sulcus stability (P = .4).

Conclusion: The addition of an arthroscopic rotator interval closure after posterior capsulolabral repair did not improve posterior stability; however, anterior stability was improved further after a rotator interval closure. Inferior stability was not improved. Arthroscopic rotator interval closure significantly decreased external rotation at both neutral and abducted arm positions.

Clinical Relevance: Arthroscopic closure may be beneficial in certain cases of anterior shoulder instability; however, posterior instability was not improved. Predictable losses of external rotation after rotator interval closure are of concern.

Key Words: rotator interval • capsulorrhaphy • capsule • glenohumeral • shoulder instability • anterior shoulder instability • posterior shoulder instability