Many individuals may notice they have decreased shoulder ranges of motion (movement). Either they have pain with movements in certain directions or they have the inability to move their shoulders due to a pinch or 'block'. Most commonly the movements to the front or side that go overhead or past 90 degrees horizontal are the most limited. Putting your hand behind your back to access your back pocket or clip your bra is also a common struggle we see in patients.
What can cause this pain?
The shoulder is a complex joint with many muscles, ligaments, bones and nerves in and around it. A very common source of shoulder pain is the impingement of the rotator cuff muscles (supraspinatus mostly). This impingement develops when there is a decrease in the space between the coracoacromial arch and the head of the humerus (where your collar bone and tip of shoulder meet your upper arm - see image below). Over time and with repetitive use, the muscles and tendons that pass through this space may begin to fray and/or tear because they are pinched between these hard surfaces. This repetitive pinching leads to tendon damage and inflammation causing pain.
What causes these joint spaces to narrow?
First of all let's become a little more aware of our anatomy. The thoracic spine is you back and spinal column from the base of your neck to your mid-lower back. Your scapula is your shoulder blade, humerus is your upper arm bone, pectoralis major and minor are your chest muscles, and kyphosis means rounding.
The space where your rotator cuff muscle passes through can narrow due to degenerative changes, bony spurs, poor postures, overhead activity, or soft-tissue thickening. Functionally, these can be affected by improper synchronicity of the rotator cuff muscles, altered scapular-humeral rhythms, or biomechanical dysfunctions with scapular positioning during arm movements. Tight and/or weak muscles usually contribute to these issues. Increased thoracic kyphosis (rounding of the upper back and spine), reduced thoracic mobility, or rounding shoulders from pectoralis minor tautness can contribute to shoulder impairment and injury as well. Below is a picture of someone with all of the above, and likely with shoulder pain and reduced mobility.
Thoracic mobility is key for shoulder motions especially overhead movements. Normal scapular and thoracic spine motion allows optimal mechanics for shoulder motions. With todays phones and laptops we are all hunched over, we don't spend nearly enough time moving our thoracic spine into extension (bending back) or rotation and thus become stuck forward. Try this exercise: standing up, hunch your upper back letting your head poke forward and shoulders as well. Now in this position, try to lift your arms straight up ahead of you and over your head, you won't get very far and could even feel pain in the shoulder. Now stand tall in upright good posture with shoulders slightly rolled back and try again. You may now achieve close to full 180 degrees of shoulder motion and the pain may be less or even gone. This just shows the importance of thoracic spine position and mobility in how the shoulder can move.
How do you fix thoracic stiffness?
Stretching: tight muscles in front of the chest and neck ie. pecs, upper traps, and suboccipitals.
Strengthening: middle and lower traps, rhomboids, deep neck flexors of the neck.
Therapy: Physiotherapists and Chiropractors can adjust and mobilize the spine as well as teach you proper exercises to increase movement.
Poor posture and chronic shoulder problems can take awhile to brew and show themselves, but when left untreated can linger for a long time and get worse. It's never too late to start working on your thoracic and shoulder mobility, strength, and posture to prevent pain!