Scapular musculature and function are extremely important when examining upper body health, strength, stability and ultimately, performance. A properly functioning scapula delivers significant stability for an individual. The scapula is connected to the thorax by the serratus anterior and subscapularis. These attachments allow the scapula to glide along the surface of the thoracic cage.
The scapulothoracic joint can elevate the scapula using the levator scapulae, upper trapezius, rhomboid major and minor. It can depress the arm using the pectoralis minor, lower trapezius, latissimus dorsi, pectoralis major. It retracts using rhomboid major and minor as well as the trapezius. As well it can protract the arm using serratus anterior and pectoralis minor.
There are many primary and secondary stabilizer muscles used in all of these different movements including the levator scapulae, the rhomboids major and minor, trapezii, and serratus anterior. If any of these are not working correctly, function is compromised and risk of injury to the notoriously fragile shoulder joint is greatly increased. Even weaknesses in these muscles can lead to shoulder impingements causing shoulder pain and a significant decrease in strength and performance.
Most sports related shoulder injuries are, at the core, the result of abnormal biomechanics which can be related to improper functioning of the scapular muscles. Scapular instability is found in 68% of rotator cuff problems and 100% of glenohumeral (shoulder) instability problems. The abnormal scapular biomechanics that happen as a result of dysfunction create abnormal scapular positions that decrease normal shoulder function and predispose the shoulder to injury. Shoulder mobility and strength are directly correlated to scapular stability, strength and functionality. As well, a strong rotator cuff is also important to shoulder health. Both complexes work as a unit when the shoulder is called upon to perform. A strong scapulothoracic joint can be rendered useless however by a weak glenohumeral joint and vice versa, so make sure your strength or rehabilitation program has you covered at all angles!
In order to restore normal scapular mechanics and function we must first re-educate the musculature surrounding it and then strengthen to reinforce this re-education. In addition to strengthening these muscles, it is also a good idea to stretch their antagonist muscles including the pectoralis major and minor, serratus anterior, and the anterior deltoid. This will allow the muscles being strengthened to work through a fuller range of motion and be less restricted during the strength building process.
There are a wide variety of exercises that exist to rehabilitate an unstable scapula. Some might be more beneficial than others and should only be selected after determining and assessing the original cause of the individual’s weakness..
First begin with stretching and mobilization exercises:
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Jeff Saibil – B.Sc. Kinesiology Strength and Conditioning Coach