Serratus Posterior Superior – Third layer down, relieves arm numbness
Posted Jan 07 2010 12:33am
A client recently came to me complaining about the numbness on the posterior forearm and into his shoulder. My initial thought was that it was infraspinatus related, from the shoulder referred pain pattern, but after relieving the trigger points in his infraspinatus, the numbness persisted in his forearm. So more investigation was required.
I found a similar pattern described by Travell and Simons in the Serratus Posterior Superior muscle, which lies deep to the Rhomboids – the third layer of muscle tissue down, beneath the Trapezius and the Rhomboids. The muscle originates on the spinous processes of the vertebrae, out to the cranial surface of ribs 2 through 5. It assists in breathing by drawing the ribs superiorly and posteriorly. When it refers pain, it commonly refers into the anterior surface of the deltoid, and down into the forearm extensors.
So, I place my client prone and place the scapula bone abducted, away from the spine. This exposes the likeliest location of the SPS’ trigger point, the attachment spot at the second rib insertion. Stretching the trapezius and rhomboid lengthen and thin out their tissues, allowing me to access the deeper layers of muscle with less effort and more accuracy.
That’s one reason I love my robot table so much; it lets me put my clients into comfortable, fully supported positions that allow me to more effeciently and effectively access tissues that are much more difficult to do on an ordinary flat table.
When I palpated the client’s insertion on the second rib, the referred pain pattern in his forearm and front of the deltoid was elicited, and I felt a moment of relief, happy that I had correctly found the source of the pain. Since the muscle is so deep, feeling its tissues becomes easier when one moves the scapula out of the way, and lengthens the shallower muscles.
Using a vaulted hand, I applied ischemic compression into the trigger point, which slowly shrank away. I think part of what is happening is that the ribs are being pulled enough to impinge upon the pathway of the brachial plexus, compressing the nodes that ennervate the anterior deltoid, and forearm extensors.
The client reported the absence of numbness at the conclusion of the session. The client’s physician had thought that it would take a good massage therapist to be able to access this layer of tissue, and that an injection would probably have been necessary to alleviate the pain. I am hopeful that that the more invasive approach will not be necessary. My next steps will probably involve the application of ice for 20 minutes to the area before attempting a shiatsu compression with the client’s breath to stretch the muscle. I can modify my table to provide excellent side-lying support by changing out the head cushion and using the U-shaped chest cushion. I love my table!
Anyway, the challenges and satisfaction at being able to find touch-related pain relief for people is very gratifying for me. It’s fun and rewarding to help other people.