Myofascial self care always starts with establishing a foundation of diaphragmatic breathing. Once you have taken a few moments get in touch with your breath, we move on to self-compression.
Recall that the subscapularis muscle is on the INSIDE of your shoulder blade. This nice lady with the big foam roller might be doing some good, but there is no chance she is going to get underneath her scapula to find that muscle.
In fact, as you can see from relative size of the shoulder blade and the tennis ball, that is will be hard to get any type of roller or ball in there.
However, if you position yourself carefully, on your side, with your arm extended, you might be able to access a small part of subscapularis in this way.
In most cases, you will have better luck with a knobber of some type that has a smaller head. We like the Back Knobber from Pressure Positive.
This type of tool allows you get into the armpit and into the space behind the shoulder blade. Approach this slowly and gently. If it is too painful you are pushing too hard, or too fast. You may need to experiment with your tool and a body position that faciliates accessing subscapularis.
There are a lot of blood vessels and nerves in the armpit, so any self- release should be done with caution. If you feel tingling or circulation changes in your arm you should reposition and take a different approach.
In the end, you may find that you can do it effectively without any self care tools and just using the opposite hand. This video provides and excellent example of manual self release of subscapularis. Most of the muscle is accessible in this position. You can also use this same technique lying on your back if the seated position is uncomfortable.
Placing the hand of the affected arm on the opposite shoulder, if possible, gently pulls the shoulder blade forward and improves access. The tenderest spot should be identified and held for 30 seconds until pain subsides. You can repeat the technique up to five times. Massage across the taut bands may also help relieve symptoms.
You can also learn to release tightness in the subscapularis by slowly and firmly stretching it using the the middle hand positions in the doorway. It is a little like a doorway stretch to open your chest. However, in this stretch, you are externally rotating your upper arm and stretching the subscapularis.
A firm, but gentle and pain-free stretch can be held for 30 seconds and repeated three to five times. You can augment this stretch with a PNF hold-relax technique.
push into the door frame with internal rotation to minimally contract the subscapularis muscle for five to ten seconds, followed by relaxation. Then gently stretch
the muscle into external rotation by rotating the body away from the doorframe.
Another approach is to use your breath to deepen the stretch. As you inhale, gently push into the doorframe. As you exhale, gently stretch by rotating the body away from the doorframe. You can repeat this sequence three to five times, up to four times per day.
Following pressure release or stretching a cold pack may be helpful.
If tightness of the posterior capsule develops it is essential that the connective tissue function with the joint be addressed in addition to restoring normal mechanics of your arm and shoulder while treating trigger points in the subscapularis. If treatment is limited to this individual muscle without addressing the mechanics of the entire joint will fail and pain relief will be temporary.