The Effect of Arthroscopic Rotator Interval Closure on Glenohumeral Volume
The role of rotator interval in shoulder pathology and the effect of its closure are not well understood. In addition, the effect of rotator interval closure on intra-articular glenohumeral volume (GHV) remains unknown.
We conducted a study to quantify the GHV reduction obtained with an arthroscopic rotator interval closure and to determine whether medial and lateral interval closures resulted in different degrees of volume reduction. We dissected 8 fresh-frozen cadaveric shoulders (mean age, 64.4 years) to the level of the rotator cuff. Volumetric measurements were taken before and after medial and lateral rotator interval closure incorporating the superior glenohumeral ligament and the upper portion of the subscapularis.
Arthroscopic closure of the rotator interval with 2 sutures reduced GHV by a mean of 45%. More volume reduction resulted with use of a single lateral interval closure stitch than with use of a single medial stitch (35% vs 24%; P < .02).
Arthroscopic rotator interval closure with 2 plication stitches is a powerful tool in reducing intracapsular volume of the shoulder and may be a useful adjunct in restoring glenohumeral stability. If a single plication stitch is preferred, a lateral stitch (vs a medial stitch) can be used for a significantly larger reduction in shoulder volume.
In a cadaveric study by Provencher and colleagues,16 open rotator interval closure with medial-to-lateral imbrication of the interval altered shoulder kinematics differently from what occurred with arthroscopic closure of the MGHL to the SGHL, resulting in superior-to-inferior shift. Comparing the 2 methods may therefore be inappropriate. Currently we reserve rotator interval closure for infrequent cases of revision instability and cases in which glenoid bone loss is marginal (5%-15%) and there is a willingness to potentially sacrifice ROM to restore stability and avoid an open stabilization procedure. Continued investigation into the clinical role of rotator interval closure in shoulder stability is needed. We should identify the pathology in a patient with instability and use this technique as an adjuvant to other stabilization procedures.
Conclusion
Arthroscopic rotator interval closure with 2 plication stitches is a powerful tool in reducing the intracapsular volume of the shoulder. If a single plication stitch is preferred, a lateral rotator interval closure stitch (vs a medial stitch) can be used for a larger reduction in shoulder volume.
