Shoulder pain can make even the smallest day to day activities like putting on a shirt painful. When it comes to shoulder pain:
- 14.7 out of 1000 people go to their primary care doctor for shoulder pain.(1)
- There is a 70% chance that you will have shoulder pain once in your lifetime. (1)
- 50% of people will have recurring shoulder pain.(1)
To better understand the causes of shoulder pain, it's helpful to know more about how the shoulder works.
The shoulder joint is a “ball-and-socket” joint. Think of it like a softball sitting on a golf tee. The shoulder is the most mobile joint in the body. Because of that, it can come under a large amount of stress, even in day-to-day activities.
It is made up of 3 main bones: the scapula (shoulder blade), clavicle (collar bone), and the humerus (arm bone). There are two main joints that make up the shoulder: the glenohumeral joint and the acromioclavicular joint.
Muscles help coordinate movement of the shoulder. The shoulder has 2 groups of muscles with 2 distinct roles: major movers and stabilizers. The major movers of the shoulder are the biceps, triceps, and deltoid. Other muscles like the pectoralis and latissimus dorsi also pitch in. The most well known shoulder stabilizers are the supraspinatus, infraspinatus, subscapularis and teres minor. You may know them as the "rotator cuff". Yes, they help to rotate the arm, but they are critical to the stability of your shoulder. Last but not least, we need to talk about bursae. Bursae are small, jelly-like pouches that act as a cushion to reduce friction between bones and soft tissues. There are two bursa in the shoulder, helping everything to move without rubbing.
Shoulder impingement:
When you hear "impingment", think "pinched." Impingement occurs when something in the shoulder is getting pinched during movement. If you experience pain when raising your arm out to the side or over your head, we would check for impingement. The muscles, ligaments, and bursae of the shoulder become pinched with abnormal reptitive movement. That pinching causes friction, which causes inflammation.
Tendinitis/Bursitis:
When you see a word end in "itis", it means "inflammation". So these two words mean inflammation of the tendon or the bursa. Also, when you see "tendinitis" or "bursitis", think "overuse". That's because these two conditions are frequently caused by overuse. The tendon or bursa experience high amounts of friction when repetition accompanies overuse. That friction causes the tendon or bursa to become inflamed. That inflammation is then perceived by your brain as pain.
Rotator cuff sprain/strain:
A sprain or strain occurs when a ligament or a muscle is overstretched or even torn. These tears can be either acute or chronic. Chronic rotator cuff sprains/strains happen with an overworked rotator cuff. When the major movers aren't doing their job, the rotator cuff will try to step up and fill in. It can be successful for a while, but eventually, the small muscles tire from the extra workload. That fatigue leads to inflammation from repetitive motion and stress (tendinitis). If that inflammation goes untreated, it becomes chronic (tendinosis). Over time, tendinosis causes the muscle to fray, leaving it vulnerable to tear. Fatigue or pain with extended activity leads us to check for a chronic rotator cuff injury. It is more common with overhead activities and sports, like baseball, volleyball, and tennis.
Labrum tears:
The labrum is a piece of cartilage in then shoulder that helps hold the ball on the socket. Acute tears happen when you dislocate your shoudler. Chronic tears happen from degeneration, as a result of repetitive use. It is frequently seen with pain in overhead movements. Painful clicking or popping in the shoulder with movement leads us to check for a tear of the labrum.
Radicular pain:
Some times you have pain that radiates into the arm. More often than not, that is less of a shoulder issue and more of a neck issue. Two causes of radiating pain into the arm are a cervical disc bulge/herniation or thoracic outlet syndrome.
For the average shoulder pain, x-rays and other advanced imaging is not needed. Imaging identifies arthritis, rotator cuff tendinsois, and labrum tears in the shoulder. Yet, these are all normal findings in healthy and pain-free patients. For example:
· In elite tennis players with no pain, 46% of them had some abnormal findings on MRI(2)
· In overhead athletes 40% had tears in their rotator cuff (partial or full thickness) (3)
· In normal adults, 34% had rotator cuff tears(4)
While imaging may be beneficial, it should used to rule out more serious causes for shoulder pain. We call those serious causes "red flags," as they do not respond to conservative treatment. As chiropractors, we use our examination to spot those "red flags." If one is present, we refer you to speak to a primary care physician or the appropriate specialist.
If our examination makes us think that you have one of the following, we will get you to the right specialist ASAP.
- Fractures: direct trauma can cause fractures. In some cases of no trauma, there might be some underlying process that leads to the bone weakening.
- Cancer: If cancer spreads to the bone, sometimes the bone will change in density. The change in density can make the bone more brittle, leading to fracture. How we “look for” cancer is by listening for subtle clues in your story. Clues like rapid weight loss without any change in diet or activity, or excessive night sweats.
- Infection: bone infections can cause a lot of pain and can have dangerous consequences if not treated soon enough.
- Heart attack: one sign of a heart attack is pain that refers to the left shoulder. If you are experiencing shortness of breath, lightheadedness, and/or discomfort in the jaw and shoulder, call 911 immediately.
Proper evaluation and understanding of the cause of your pain are critical so that you can get to the appropriate specialist as soon as possible.
During an evaluation, your doctor will review your medical history with you. Then, they will perform a thorough physical examination. This process is to rule out any serious causes of shoulder pain.
When you have pain in the shoulder or arm, it is our job to determine what structure is causing the pain. For example: is the pain local from a tendon or bursa? Or is the pain radiating into the arm because of a disc bulge or a nerve irritation?
Finding out the “what” is only half the job. The “what” is the structure that is causing you pain. Finding out the “why” of your shoulder pain is of utmost importance. We need to find out “why” the “what” is being irritated. The sooner we know the “why”, the sooner you can figure out how to move so that the “what” is no longer irritated.
Corrective exercises and mobility can help with most cases of shoulder pain. A study5 showed that physiotherapy [exercises] were as effective as surgery for treatment success and quality of life. The study also recommended that patients stick to the physiotherapy program for at least 12 months before the option of surgery is seriously entertained.
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3127806/
- https://bjsm.bmj.com/content/48/7/612.2
- https://pubmed.ncbi.nlm.nih.gov/12975193/
- https://journals.lww.com/jbjsjournal/Abstract/1995/01000/Abnormal_findings_on_magnetic_resonance_images_of.2.aspx
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6539146/