Frozen shoulder, also known as adhesive capsulitis, isn’t as official as it sounds. Frozen shoulder just refers to shoulder pain that leads to restricted range of motion. It is a catch-all diagnosis for shoulder pain and immobility for which the underlying cause is unknown.
Janet Travell, the author of Myofascial Pain and Dysfunction: The Trigger Point Manual, speaking of the medical literature on frozen shoulder, says, “When so many authors agree that the cause of a disease is enigmatic, there is good reason to expect that a major etiologic factor is being overlooked.”
This major factor, according to Travell, is trigger points in the subscapularis muscle. Acupuncture can eliminate these trigger points, wiping out frozen shoulder for good and offering people an alternative to the common—yet usually only temporarily effective—protocol of pain killers, cortisone shots, and surgery.
The signature pain-referral pattern of subscapularis trigger points
The subscapularis is one of the four muscles that comprise the rotator cuff. It attaches to the inner surface of the scapula and to the front of the humerus bone. Its primary responsibility is to hold the humerus in place during arm movements, preventing displacement. It also helps internally rotate the head of the humerus.
Trigger points are sensitive nodules in the musculature that cause referred pain. In the subscapularis muscle, they produce a signature pain-referral pattern. Pain concentrates on the back of the deltoid muscle. From there, it can extend onto the back, over the scapula, and/or down the back side of the upper arm. Pain usually skips the forearm but appears again as a band around the wrist (see picture at right).
Early-stage subscapularis trigger points normally don’t prevent people from reaching up. However, reaching backward—as if you were getting ready to throw a ball—tends to be painful. This is why frozen shoulder and adhesive capsulitis are sometimes referred to as pitcher’s arm.
Another tell-tale sign of early-stage subscapularis trigger points is wrist pain that concentrates on the back of the wrist, sometimes making it uncomfortable to wear a watch.
Common causes of shoulder pain from trigger points in the subscapularis
Is it sounding like your shoulder pain might be coming from trigger points in the subscapularis muscle? Here are some common ways in which these trigger points get activated:
Overdoing it at activities that require medial rotation of the arm. Examples include freestyle swimming and throwing a baseball.Forceful overhead lifting while adducting the arm (bringing it closer to your body). An example is the kettleball swing exercise, where you use outstretched arms to raise the kettleball from between the legs.Sudden stress placed on the shoulder muscles due to a humerus fracture or shoulder-joint tear, or breaking a fall.
Once a trigger point is activated—in the subscapularis or any muscle—it’s commonly perpetuated or exaggerated by everyday movements. Sleeping on one’s side or having slumped-forward posture can make subscapularis trigger points worse.
Cures for subscap-related shoulder pain
Once you’ve identified subscapularis trigger points as the source of your shoulder pain and immobility, there are several steps you can take to reduce them.Get acupuncture
Trigger points in the subscapularis can be released by inserting acupuncture needles directly into the muscle. While extremely effective at eliminating shoulder pain, having these trigger points needled can be uncomfortable due to the location of the subscapularis. To access the muscle, the acupuncturist needs to palpate somewhat forcefully inside the underarm (see picture at right).
Another acupuncture technique for addressing pain from trigger points includes needling away from the actual pain site, choosing points along the acupuncture meridians that transverse the painful part of the body.
For example, the Small Intestine meridian runs directly along the signature pain-referral pattern for subscapularis trigger points. An acupuncturist might choose to needle an acupuncture point on the Small Intestine meridian that’s farther down the body.
Small Intestine 3, for example, is an acupuncture point on the side of the hand (see picture at left) that’s frequently used to alleviate shoulder and upper back pain around the scapula. You can massage this point yourself to help reduce pain in that area.
Adjust your posture
Something else you can do yourself to reduce subscapularis-related shoulder pain is adjust your posture—while awake and sleeping.
During waking hours, try and avoid the slumped-forward posture that so many of us have unfortunately developed as a result of sustained computer use. This position forces the arms into a medially rotated position, which perpetuates trigger points in the subscapularis.
When standing, try hooking your thumbs into your belt or pants to prevent your arms from touching your sides. You can also try the amazingly simple palms-up trick for improving posture. When you’re at your desk, remember to frequently move your arms—a simple movement of reaching the arm up and behind the head will do it—to help keep the subscapularis muscle stretched.
Sleep with a pillow
At bedtime, grab an extra pillow. If you’re sleeping on the painful side, place the pillow between your elbow and side of the body. Again, this abducts the arm away from the body, which stretches the subscapularis muscle. If you sleep on the pain-free side, put the pillow in front of you so that the painful arm can rest on it (pretend you’re hugging the pillow).
Any pillow will do, but if you want to get fancy, I have heard good things about this side-sleeper pillow.
Do the doorway stretch
A final self-care technique for reducing subscapularis trigger points is the doorway stretch. Stand in a doorway and place both hands on either side of the door, at about shoulder height. Lean forward to give a nice passive stretch to the subscapularis.
If your shoulder pain is coming from trigger points in the subscapularis muscle, no amount of pain killers, cortisone shots nor surgeries is going to solve the problem. Those treatments have their place, but why not try the less invasive path first?