How to treat posterior glenohumeral instability
Previous research has underestimated the incidence of posterior glenohumeral instability (PGI). This systematic review aimed to determine the best evidence-based conservative treatment for patients with PGI.
Patients with PGI often showed an increased glenohumeral retroversion. Especially individuals who are engaged in activities that bring the shoulder repetitively in a position of flexion, adduction and internal rotation and individuals with a generalised ligamentous laxity are at a high risk for the development of PGI.
Patients with PGI often complain about an aching pain and weakness along the posterior glenohumeral joint line or a tightening sensation felt around the posterior cuff. Frequently, there can be a clicking sensation around the posterior joint line.
A systematic review had been carried out. Only 5 low quality studies could be found:
2 studies that have used EMG biofeedback to enhance posterior deltoid recruitment showed pain relief or even full pain resolution.
1 strengthening study aimed to strengthen the deltoid and rotator cuff muscles using a theraband, found good to excellent post-intervention results.
2 studies on scapular stabilization with the focus on an optimal scapular and humeral head positioning, showed an overall recurrence of 18-24%. It was found that those with an atraumatic history of instability have more favorable outcomes than those with a traumatic onset.
Scapular stabilization prior to strengthening yielded promising results for instability recurrence, however only those without a surgical history responded well to stabilization and strengthening programs. This might be caused because the instability in those who received a surgery was more severe. EMG biofeedback can be used to re-educate an abnormally underactive posterior deltoid, and may be effective in preventing or decreasing episodes of PGI, again mainly in an atraumatic population.
Thus, conservative rehabilitation focusing on rotator cuff and posterior deltoid
strengthening may reduce instability recurrence and pain and increase function in PGI.
> From: McIntyre et al., Phys Ther Sport (2016) (Epub ahead of print). All rights reserved to Elsevier Ltd. Click here for the Pubmed summary.