You may have read my recent columns about two rotator cuff muscles of the shoulder: the infraspinatus and the supraspinatus. The rotator cuff is made up of four muscles that stabilize the shoulder joint and help provide its diverse range of motions. Like the hip, the shoulder is a ball-and-socket joint -- one where a knobby bone fits into the cavity of another bone, allowing great freedom of movement when healthy.
So, how about when it is not so healthy? Well, another of the little-known muscles of the rotator cuff is called the teres minor. It can cause a lot of discomfort when injured, irritated or overworked. Like the last two muscles I wrote about, the TM has a unique role to play. It attaches from the outside edge of the scapula (think very outer edge of your upper back) to the head of the humerus and weakly rotates the shoulder backwards. This movement is also called external rotation.
I've seen this muscle create very deceptive tricks when it has active trigger points. One example is what I call "mouser's arm." This can happen when a person has been using the computer mouse too much, which statically engages the teres minor. I say "statically" because there isn't a lot of broad movement when we are using this little device.
Mousing doesn't create a lot of blood flow to the muscle, but it does contract it. This long-term contraction can irritate the TM, and the result can be tingling or numbness through the pinky finger side of the forearm and wrist, and sometimes even into the hand. I say it is a deceptive trick because all of these sensations come from the overworked teres minor -- which is way up in the shoulder. The key giveaway that this is the scenario is that when the TM is palpated or pressed on, the symptoms in the wrist and forearm will show up and/or be amplified. By releasing the restricted points, the uncomfortable symptoms fade away.
To continue with its deceptiveness, consider that referred pain from the TM is sometimes masked by deeper pain in the front of the shoulder which originates in the infraspinatus. When the infraspinatus is treated, sometimes clients begin to sense discomfort in the back of the shoulder, which is caused by teres minor. This pain in the back of the shoulder is actually the most common trigger point referral for TM and becomes pretty obvious when it is treated.
Whichever area you feel the bite of TM, you will probably agree that although it has "minor" in its name, it can become a major pain.
David Pratt is a Licensed Massage Therapist with multiple advanced certifications. He has been serving Holmes County clients since 1997 and has a private practice, True Nature, in Millersburg. He can be reached at 330-473-0402 or firstname.lastname@example.org. As always, Holmes County residents receive a discounted rate.