The shoulder is an exceptionally complex joint involved in many everyday activities such as reaching, pulling, waving and pointing, as well as in sport-specific movements such as swinging a bat or throwing a ball. Because the joint is so complex (to allow for a large range of motion) it is vulnerable to injury. In my own physical therapy practice, I treat many clients (especially men) for shoulder impingement. As such, it is important, as a fitness professional, to understand the in’s and out’s of shoulder impingement in order to safeguard your clients against it and treat it properly should it occur.
This article will review the following about shoulder impingement:
Common signs and symptoms and contributing factors
Physical therapy management
Exercises that are contraindicated with rationale
Shoulder impingement (SI) is the mechanism in which the supraspinatus tendon of the rotator cuff becomes impinged as it passes through a narrow bony space called the sub acromial space. With repetitive movement, the supraspinatus tendon can become irritated and inflamed. SI can also be caused by a decrease in posterior capsule mobility and weakness of scapulothoracic musculature. Evidence-based research has shown that shoulder impingement is a common condition believed to contribute to the development or progression of rotator cuff disease (Ludewig, P. 2011).
Decrease in sub acromial space comprises the supraspinatus tendon, predisposing it to micro tears leading to degeneration and ultimately tearing
Tightness of the posterior capsule causes the humerus to migrate anterosuperior into the AC joint
Weakness of scapulothoracic muscles leads to abnormal positioning of the scapula
Clients will complain typically of pain in the front of the shoulder, described as a deep, dull ache with stiffness. Reaching overhead and behind one’s back will elicit pain.
Poor posture, repetitive overhead work and tight posterior capsule are some contributing factors. Per the research, the development of SI has been correlated to abnormal muscle activation. Specifically, those with SI, present with overactive upper trapezius and underactive lower trapezius muscles (Chester, R., et al. 2010).
The goal with physical therapy is to restore scapular mobility, followed with stretching to restore full range of motion (figure 2). Strengthening focuses on targeting the weaker upper posterior musculature, including; the rhomboids, low trapezius, external rotators and serratus anterior muscles. Then the patient is taught scapular stabilization and dynamic strengthening exercises.
Once discharged from physical therapy, transitioning to the gym should be simple and based on science, NOT guesswork. The focus on post rehabilitation training is to strengthen the scapular stabilizers (rhomboids, low trapezius, posterior deltoid and external rotators) and posterior shoulder. Core strengthening should progress from static to dynamic exercises.
Low trapezius pull downs (figure 4) with cable standing or tubing depresses and retracts the scapula, unloading the anterior shoulder, improving posture and posterior stability.
Seated mid row, one arm dumbbell row and seated reverse flyes (posterior deltoid) strengthen the weaker phasic muscles of the posterior chain.
External rotation with cable, seated reverse flyes and seated dumbbell side raises.
Core strengthening exercises that are safe include, but arebnot limited to; standing trunk rotation with cable/tubing, diagonal with cable tandem in place lunge, planks, planks with ball, trunk rotation with forward lunge.
Seated dumbbell shoulder press (creates excessive load to the medial deltoid).
Lat pull downs behind the head (at end of range places greatest stress on all glenohumeral ligaments as well as on the labrum).
Upright row (at end of range the shoulder is maximally internally rotated which places stress on all glenohumeral ligaments, labrum and connective tissue).
Shoulder impingement is a common shoulder condition that a fitness professional may encounter. Understanding the anatomy, biomechanics and proper programme design with evidence-based training strategies, will provide you with a better understanding to work with clients suffering from this condition.
Bernhardsson, B., et al (2012), ‘Evaluation of an exercise concept focusing on eccentric strength training of the rotator cuff for patients with sub acromial impingement syndrome, Clinical Rehabilitation, pp. 1-9.
Chester, R., et al. 2010, ‘The impact of subacromial impingement syndrome on muscle activity patterns of the shoulder complex: a systematic review of electromyographic studies’ BMC Musculoskeletal Disorders, vol. 11, issue 45, pp 1-12.
Holmgren, T., 2012, ‘Effect of specific exercise strategy on need for surgery in patients with sub acromial impingement syndrome: randomized controlled study,’ British Journal of Medicine, pg. 344.
Kuhn, J., 2009, ‘Exercise in the treatment of rotator cuff impingement: A systematic review and a synthesized evidence-based rehabilitation protocol,’ Journal of Shoulder Elbow Surgery, vol. 18, pp. 38-160.
Ludewig, P., 2011, ‘Shoulder Impingement: Biomechanical Considerations in Rehabilitation,’ Journal of Manual Therapy, vol. 16, issue, pp. 33–39.