Publication At A Glance

Triangle Tilt Surgery: Effect on Coracohumeral Distance and External Rotation of the Glenohumeral Joint

For individuals with obstetric brachial plexus injury (OBPI), the primary injury is the nerve injury and among the secondary injuries are muscle imbalances and bone deformities. We study many aspects of the shoulder and functional movement pre and post surgery. One area that is highly interesting is the "coracohumeral distance" - the distance between the coracoid process and the humeral head. These 2 structures hold the ligaments of the front of the shoulder. When the ligaments become too tight after brachial plexus injury, 2 things happen: (1) Shoulder outward (external rotation) movements are hindered and decreased (2) The distance between the coracoid and the humeral head is decreased (this can be seen on CT scans)

For our study, we took twenty (OBPI) patients that had the secondary muscle imbalances and bone deformities. We measured the coracohumeral distance pre and post Triangle Tilt surgery through the use of CT scans. The measurement of functional movement (Mallet Scale) was accomplished through video recordings.

This is what our study concluded about the Triangle Tilt Surgery:

• (1) there was significant improvement in the distance between the coracoid process and the humeral head
• (2) this increase in distance significantly improved all external rotation and total Mallet scores (function was improved)
• (3) it also reduced excessive tightness in the ligaments in the front of the shoulder