Suffering from shoulder pain can make simple tasks seem like a nightmare. A simple reach for a cup or a quick reach for a pen can strike early and often. Your shoulder’s first attach can come early. A simple reach towards a buzzing alarm could result in a knife-like pain. Forget reaching into the back seat of the car… ouch! Winter is coming… what about putting on a jacket? You’re likely putting the “bad” arm in first out of fear. Sound familiar?
What is causing the pain?
Interestingly about 44-65% of shoulder pain is caused by shoulder impingement (1). Impingement occurs when the rotator cuff muscles are pinched during movement. This pinching occurs as the rotator cuff muscles get smashed between the arm bone and the boney arch on the shoulder blade. No wonder it hurts! Why are you unable to perform these simple tasks pain free as you once did before? It’s easy to blame the arm; however, you may want to redirect your anger towards the close neighbor: the shoulder blade.
While the shoulder blade may seem like a distant thought on your back it is an extremely important part of the shoulder. The shoulder blade coordinates with your upper arm during tasks involving reaching at various angles. While it may seem simple, this coordination requires nearly flawless teamwork of the arm and shoulder blade to stay pain free. The shoulder blade has 17 muscles which help with its movement. All it takes is one muscle not working properly to throw off the whole scheme.
Lack of mobility
Limited mobility at the shoulder blade is common for those dealing with shoulder pain. Reaching overhead requires the shoulder blade to move outwards, rotate upwards, eventually tipping backwards at the top end of range. Proper movement allows for clearance of the arm bone and NO PINCHING of the rotator cuff muscles. Here’s where we throw sitting under the bus. Unfortunately, our prolonged, static, flexed postures make it rather difficult for the shoulder to move along the proper path.
Muscle Imbalance

Of the 17 muscles in the shoulder blade weakness in the lower trapezius and serratus anterior is the common culprit leading to shoulder pain (2). These muscles allow the blade to properly move out of the way of the arm bone during movement. Combine that weakness with the over worked upper trapezius (shrugging muscle) and deltoids and the result is poor movement and an eventual injured shoulder. Once this muscle imbalance (some too strong and others too weak) becomes prevalent it is a vicious cycle.
You can perform these two exercises to help with proper scapular mobility to prevent rotator cuff injuries:

Begin by shifting hips to LEFT and swinging your RIGHT hand towards your LEFT hip. Then shift your hips to the RIGHT and turn your thumb up towards the ceiling and swing your arm up and out to the side. Can perform without weight and as you improve add a light dumbbell. The exercise is meant to be one fluid motion. Perform on both sides.

Turn hips/shoulders towards LEFT hip and sweep RIGHT arm across body with palm facing downward. Turn trunk towards RIGHT hip and open palm up and continue until you feel restriction through your RIGHT hip. Perform in one smooth motion. Keep arm parallel to ground. Perform on both sides.
Avoid the painful pinch by making sure your shoulder blade and arm bone are working as a team. These two simple exercises will help the mobility of the shoulder blade. Add these to your morning routine and make waking up less painful!
To consult a physical therapist about your shoulder pain, click the link below to schedule your free discovery visit at Buffalo Rehab Group.
References
1. Ludewig, Paula M., Reynolds, Jonathan F. The Association of Scapula Kinematics and Glenohumeral Joint Pathologies. J Orthop Sports Phys Ther. 2009 February ; 39(2): 90–104
2. Scapular and Rotator Cuff Activity During Arm Elevation: A Review of Normal Function and Alteration with Shoulder Impingement. Rev Bras Fisioter, São Carlos. 2009. 13: 1-9.