I regularly see clients with shoulder pain. Common presentations include, sub-acromial impingement either due to bursitis or a supraspinatus tendinopathy (sometimes described as tendinitis), lots of rotator cuff issues, tears and tendinopathies and simple postural issues with rounded shoulders leading to impingements.
The shoulder is a complex joint with massive range of motion (ROM). Because of this it’s easy to think a lot can go wrong with it. Much has been written in scientific journals about shoulder mechanics, particularly about the rhythm of humerus movement in relation to the scapular and the importance of relationship between the pectoral muscles at the front and the shoulder retractors at the back. It is common to hear that the serratus anterior is not firing properly or the upper traps have too much activity and this is leading to dysfunction but actually there is no good quality evidence to support these ideas and anecdotally I have often found they lead to a complicated diagnosis requiring very specific exercises. Over the years I have come to understand that the specificity of theses exercises can be confusing and if the patient is confused they are often less likely to comply with the exercise protocols. At LMC we therefore try to take a much simpler, common sense approach, to identify the movement (or movements) that cause pain and then focus specifically on rehabbing these patterns and actually this approach is supported by the evidence
Movement Dysfunction Evidence
It is accepted that when people have shoulder pain they are likely to move their shoulder differently and changing movement patterns is a valid treatment intervention but the one size fits all approach trying to rehab a specific ideal movement pattern, not supported in the literature. There are however a few studies that look at how kinematics change with rehab. Here are three that show people get better with either no change in kinematics (Carmargo 2016) or the rehab resulted in what many would consider poorer kinematics (e.g. decreased upward rotation, increased protraction seen in Struyf 2013 and McClure 2004)
The take away point here is if somebody has told you the reason your shoulder hurts is because of a specific muscle imbalance (the most common I hear is tight pectorals) then ask them for the evidence to support this. The truth would appear to be that if you have shoulder pain with movement doing exercises to change the way you move is probably a good idea but exactly how does not matter. You simply want to eradicate the movements that cause or maintain the pain. You can look at the massive variety of movement strategies in high performing athletes to see there are many good ways for the shoulder to move.