Your posture can be causing your shoulder pain
How your back may be contributing to shoulder impingement syndrome.
The following article shines light on a secret that many people with shoulder pain need to see. “Subacromial space in adult patients with thoracic hyperkyphosis and in healthy volunteers.1” This article caught my attention not because of the catchy title, no offense to the authors, but because of how common I see subacromial impingement syndrome being associated with misalignments in the back. Since subacromial impingement syndrome is becoming a more common diagnosis in people with shoulder pain I thought that I needed to share this with everyone who comes in contact with our practice.
The article basically correlates the narrowing of the subacromial space with hyperkyphosis (i.e. overly curved upper back due to organic causes or slouching due to poor posture muscle training). The more the curvature in the thoracic spine the smaller the subacromial space. This is important because the smaller the subacromial space the more likely the chances of getting irritation in that space and setting off subacromial impingement syndrome or subacromial bursitis or tendonitis.
The idea is that as our upper back curves into hyperkyphosis (excessive curvature of the thoracic spine) it automatically causes the scapulae to follow the rounded curve. This allows for the scapulae to slide anterior and encroach on the subacromial space.
Assuming the person does not have scoliosis or another organic cause of the curvature, the person could combat the narrowing subacromial space by doing a series of posture exercises. These posture exercises would strengthen the thoracic spinal muscles that hold posture and thus hold the scapulae from sliding forward and encroaching on the subacromial space.
In the case of posture, it is not a momentary glitch that causes the problem. It is years of poor posture that narrows the subacromial space and causes excessive wear and tear in the normal everyday movements. With time this excessive wear and tear brings about the most damage and eventually one day it catches up to the person. That day it may seem so random or out of the blue but when the lead up is taken into consideration it makes perfect sense.
Subacromial impingement syndrome is a complex condition that has roots in many different proposed mechanisms. The main associated causes of subacromial impingement syndrome are muscle weakness, shoulder overuse, tendonopathy, shoulder instability, degeneration of the acromioclavicular joint, thickening of the coracoacromial ligament, improper biomechanics-i.e. the way the shoulder muscles coordinate movement with each other.2
Subacromial impingement syndrome is mainly marked by the symptom of pain in the anterior superior shoulder. The pain is worsened when the arm is internally rotated and/or raised above the head. The pain is debilitating for most people. It is diagnosed mainly by history and physical exam but may need imaging to rule out other causes.
In people under 40 years of age it is hard to differentiate subacromial impingement syndrome from a glenohumeral laxity and in people older than 40 years of age it is often seen with concomitant findings such as rotator cuff tears and bursitis.
Since subacromial impingement syndrome is so painful it behooves all of us to focus on holding our thoracic spine and scapulae in good posture to help prevent it.
1Subacromial space in adult patients with thoracic hyperkyphosis and in healthy volunteers. Stefano Gumina, Giantony Di Giorgio, Franco Postacchini and Roberto Postacchini. LA CHIRURGIA DEGLI ORGANI DI MOVIMENTO (2008) Pages 93-96.
2Current Concepts Review - Subacromial Impingement Syndrome. LOUIS U. BIGLIANI, M.D., WILLIAM N. LEVINE, M.D., The Journal of Bone & Joint Surgery. 1997; 79:1854-68)