Many years ago now, I attended a talk by Dr. Emil Pascarelli to the RSI/Mass COSH group in Boston and was cheering to myself in the back of the hall when I heard him say that most Repetitive Stress/Strain Injuries start in the upper body. That had been just my experience in treating lots of RSI patients in my NMT Center near Boston. After months of treatment, the forearms would become less sensitive and stronger, but there would still be pain in the muscles of the upper body. Resolving those issues was a key that opened the door for me to be more successful in treating RSI and then of many other painful complaints in the arms and hands.
What is important to understand is that when the upper body muscles are tight they can block the flow of blood and nerve signals to the arms. If there is reduced blood flow to the working muscles, they can’t stay healthy, especially if they are overworked by hours on a computer or by one-sided vigorous exercise. They run out of energy, nutrients and oxygen and get strained and injured.
When the nerves are trapped, signals can’t get back and forth to the spinal cord and brain that control movement, systemic balance and all communication to and from the muscles.
When blood flow is reduced, not only do the muscles get starved, but waste products produced in the arms by the work the muscles are doing can’t be removed efficiently. They build up and cause a toxic condition which causes pain and breaks down the cells that make up the soft tissue. The lymphatic system, working with the circulatory system and essential to life also becomes blocked, adding to the toxicity and ill health.
The most important muscles that cause this condition are the scalene muscles in the neck, the pectoralis minor in the chest, the subclavius under the collarbone and the subscapularis in the armpit (axilla). The thoracic outlet pertains to the triangular space between two scalene muscles and the first rib. The nerves from the neck that go down the arm can be trapped in this triangle when the muscles are tight. The major artery from the heart joins the nerves, forming a neurovascular bundle that goes over the first rib and under the collar bone (clavicle) and pecoralis minor muscle before splitting in the axilla and going down the arm. Tension in the thoracic outlet space can cause “thoracic outlet entrapment” or the more serious “thoracic outlet syndrome.” Entrapment can block blood and nerve flow to the arms causing pain, tingling, numbness (dysesthesia) and unusual sensations (parasthesias).
Entrapment also commonly occurs under the pectoralis minor’s very strong tendon and can be felt as numbness when the arms are overhead.
In the axilla, the brachial plexus of nerves split into the various branches that send messages to different parts of our arms. Tension in the axilla, primarily in the subscapularis muscle can impact those nerves.
To reduce symptoms and improve soft tissue health, the tension and Trigger Points in all of these muscles must be relieved so that the blood, lymph and nerves can do their jobs. Then the muscles can begin to rebuild.