I've just been doing some investigation for a current medico-legal case and found a superb paper detailing exactly what I was looking for. It's good to see more case studies/papers being presented that lend good weight to a challenging orthotic case. Below is an excerpt and underneath that is a link to the full article.
Children with obstetric brachial plexus palsy often present with shoulder alignment issues. Shoulder subluxation may occur as a result of shoulder girdle muscle weakness and overstretching of the ligamentous support structure around the glenohumeral joint. Optimal alignment and support of the glenohumeral joint is essential for active functional shoulder movement and distal control. Shoulder support options are limited for children, because materials may not be suitable for daily wear and compliance is often poor. The purpose of this case study was to evaluate the effectiveness of a custom-fitted shoulder orthosis, the Dynamic Movement Orthosis (DMO), and its ability to support and improve upper limb function during active wear. The Wolf Motor Function Test assesses 17 tasks (2 strength based, measured by weight lifted and grip, and 15 function based, measured using time to completion). This test was used to objectively quantify active shoulder and elbow movements with and without the use of a custom-fitted DMO. This case study suggests that the DMO supported the shoulder during functional task and optimized active strength distally in the wrist and elbow. (J Prosthet Orthot. 2011;23:159 –164.)
Full paper is a very interesting read and can be found HERE.