The Subscapularis
The Subscapularis Muscle: Trigger Points and Referred Pain
Where Is the Subscapularis Located?
By Anatomography (en:Anatomography (setting page of this image)) [CC BY-SA 2.1 jp], via Wikimedia Commons
About the Subscapularis
The Subscapularis is the largest of the four rotator-cuff muscles. It lies on the front surface of the shoulder blade, between the shoulder blade and the rib cage, and attaches to the front of the upper arm bone.
It helps rotate the arm inward and assists in keeping the upper arm centered and stable in the shoulder joint. Because most of the muscle is covered by the shoulder blade, only a small portion near the armpit can be reached directly.
Subscapularis Referred Pain and Related Symptoms
Trigger points in the Subscapularis may refer pain deep inside the back of the shoulder. Discomfort may also extend around the shoulder blade and down the back of the upper arm toward the wrist.
- Deep aching in the back or inside of the shoulder.
- Pain that may extend down the back of the upper arm.
- Discomfort around the shoulder blade.
- Pain on the top of the wrist.
- Difficulty reaching behind the back.
- Discomfort when raising or rotating the arm.
These symptoms may resemble those associated with the shoulder joint, rotator-cuff tendons, frozen shoulder, or irritated nerves. A referred-pain pattern may provide a useful clue, but it cannot confirm the cause of shoulder or arm pain.
The image above shows possible Subscapularis trigger points and referred discomfort.
What May Contribute to Subscapularis Trigger Points?
- Repeated throwing, swimming, or overhead movements.
- Forceful pulling or pushing activities.
- Holding the arm inward or across the body for long periods.
- A sudden increase in upper-body exercise or activity.
- Keeping the shoulder immobilized after an injury.
- Insufficient recovery between demanding shoulder activities.
How to Help Prevent Subscapularis Trigger Points from Returning
- Increase throwing, swimming, and overhead activity gradually.
- Take breaks from repetitive shoulder movements.
- Use comfortable shoulder positioning while working and sleeping.
- Warm up before demanding upper-body activity.
- Maintain comfortable shoulder mobility without forcing the movement.
- Allow enough recovery time between strenuous activities.
Reducing or modifying the aggravating movement may be as important as massaging the tender area.
Subscapularis Self-Massage
Gentle self-massage may help reduce tension and tenderness in the accessible part of the Subscapularis.
Subscapularis Massage
Subscapularis Massage Instructions
To massage the right subscapularis muscle raise your right arm only as high as is comfortable. With the fingertips of your opposite hand, gently explore the muscular area along the outer edge of the shoulder blade, just behind the armpit. Keep your fingers outside the armpit rather than pressing deeply into it.
My fingers are on the the lateral side (outside) of the armpit and not in the middle of the armpit! When you locate a tender area, apply light, comfortable pressure for a few seconds, then release. You may also use small, slow massage movements. This area can be sensitive, so work gradually and never force the pressure. The Subscapularis muscle and the Latissimus dorsi muscle are close together in this area, so this technique may allow you to massage both muscles at the same time. Avoid pinching deeply inside the armpit.
Use caution: Do not press deeply inside the armpit, where important nerves and blood vessels pass. Stop immediately if the massage causes sharp pain, numbness, tingling, weakness, dizziness, or discomfort traveling down the arm.
Sources and References
- Clair Davies and Amber Davies. The Trigger Point Therapy Workbook: Your Self-Treatment Guide for Pain Relief. New Harbinger Publications, 2013.
- Anatomy, Shoulder and Upper Limb, Subscapularis Muscle — NCBI Bookshelf.
- Anatomy, Rotator Cuff — NCBI Bookshelf.