Subscapularis means under (sub) the scapula (the wingbone). lt is the largest, strongest and most-used of the rotator cuff muscles of the shoulder, involved in rotating the arm inward, moving the arm towards the midline of the body (adduction) and stabilising the head of the humerus into the shoulder socket. It can be the hidden source of shoulder pain, weakness and reduced movement, yet it is often overlooked and undertreated. Let's face it, when we have pain and find it hard to move, it can affect far more than just our physical sense of wellbeing. Because of this, it is one of my favourite muscles to treat because it can make such a big difference to a person's ability to function and do normal daily activities.
Overhead athletes such as throwers, tennis players and swimmers can suffer injuries to subscapularis with tendonitis resulting in pain when raising the arm above the shoulder. This muscle is also often involved in frozen shoulder and tender trigger points can develop, referring pain to the back of the shoulder and shoulder blade, down the back of the arm to the elbow and around the wrist. These can be evident in reduced range of movement, particularly in actions such as taking the arm back to throw a ball, touch the back of the head or put a jacket on. This can extend to lifting the arm out from the side and the shoulder can become painful with both movement and when resting.
Activities that can result in trigger points in subscapularis include repetitive forceful internal rotation of the shoulder such as with throwing a ball, using a racket or freestyle swimming and repeated forceful lifting such as lifting a child overhead and down. Sleeping on one side, reaching back to grab a handrail when preventing a fall, dislocating the shoulder, and prolonged immobilisation of the shoulder after an injury can also cause trigger points to develop.
When treating subscapularis, I have found that a combination of trigger point therapy, muscle energy techniques and mobilisation are effective tools in addressing shoulder pain and reduced movement associated with this muscle. Engaging the client in the process with active movement and diaphragmatic breathing is also important as the only way of accessing the muscle is via the armpit – an often sensitive area. Homecare activities are an important part of treatment. Using a pillow as a bolster for the affected arm and elbow when sleeping on the opposite side helps by taking tension off the shoulder. Postural awareness through avoiding a slumped, forward head posture prevents the muscle becoming overly shortened. Stretches such as the doorway stretch can assist with improving muscle length, while resistance exercises with bands or small hand weights can help regain strength, together improving shoulder mobility and function.
Treatment may require a number of sessions to resolve symptoms depending on the underlying cause and chronicity of the condition, but results can make a huge difference to reducing pain and improving movement in daily activities.
Sources:
Davies, C. (2006). Frozen shoulder workbook: Trigger point therapy for overcoming pain & regaining range of motion. Oakland, CA: New Harbinger Publications.
Kent, D. (2008). Subscapularis: Overlooked and undertreated. Massage Today, 8(11). Retrieved from http://www.massagetoday.com/mpacms/mt/article.php?id=13889
National Association of Myofascial Trigger Point Therapists. (2015). Symptom Checker: Subscapularis. Retrieved from http://www.myofascialtherapy.org/symptom-checker/symptomcheck/symptom_upper_subscapularis.html
Physiopedia. (n.d.). Subscapularis. Retrieved from http://www.physio-pedia.com/Subscapularis
Simons, D. G., Travell, J. G., & Simons, L. S. (1999). Travell & Simons' myofascial pain and dysfunction: The trigger point manual, volume 1: upper half of body (2nd ed.). Baltimore, M.D: Williams & Wilkins.
Thurner, M. S., Donatelli, R. A., & Bascharon, R. (2013). Subscapularis syndrome: a case report. International journal of sports physical therapy, 8(6), 871-882. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3867080/#