Outcomes of glenohumeral dysplasia after brachial plexus birth injury using the Sup-ER orthosis.

We investigated the efficacy of the supination-external rotation ('Sup-ER') orthosis, designed as a non-operative treatment to maintain normal anatomical growth of the shoulder, on the progression of glenohumeral dysplasia in patients with brachial plexus birth injuries. The Sup-ER orthosis was fabricated for 20 infants diagnosed with glenohumeral dysplasia after brachial plexus birth injuries and its success in correcting glenohumeral dysplasia was confirmed by objective calculations of the alpha angle on serial ultrasound findings and improvement in Active Movement Scale scores. Of the 20 patients, 14 had successful resolution of glenohumeral dysplasia, confirmed by shoulder abduction, shoulder flexion, external rotation and supination, Active Movement Scale scores and improving alpha angle measurements. Failure to rectify glenohumeral dysplasia, evidenced by worsening ultrasound findings and Active Movement Scale scores, necessitated a change to operative management in six patients.Level of evidence: IV.