http://nerve.wustl.edu/TOS.pdf

"Double Crush Syndrome
Patients with thoracic outlet syndrome usually have symptoms of tingling and numbness in the hand. These hand symptoms are similar to those of carpal tunnel syndrome and cubital tunnel syndrome. The “double crush” mechanism may play a role in the development of symptoms in patients with thoracic outlet syndrome. The nerve fiber begins in or near the spinal cord and then goes all the way to the hand to give sensation and movement to the arm and hand. If the nerve is pinched at one place, then it is less likely to tolerate any more pressure along the nerve. Therefore, other tight places, such as at the wrist (carpal tunnel) or elbow (cubital tunnel), are more likely to produce symptoms with very little added pressure.


i never really thought about this but it makes sense. thats why i can push on different places like my arm, first rib pec, arm pit blah blah and make my hands tingle



With thoracic outlet syndrome, it appears that arm overhead positions and downward pulling (like carrying a heavy bag) increases pressure on the brachial plexus...........
Because pressure on the brachial plexus is irritated with arm overhead positions and these positions often cause significant discomfort; the progression of nerve compression will be much slower because you will be uncomfortable in these provocative positions and quickly learn to avoid them. This protective habit may however limit your range of movement and make certain muscles very tight........


The idea of the “double or multiple crush” is that patients with nerve compression at one site are more likely to develop nerve compression at another site. There are some diseases that can be the first “crush”; for example patients with diabetes, hypothyroidism, rheumatoid arthritis or alcoholism are more susceptible to developing symptoms from nerve compression. Some people have a hereditary susceptibility to develop nerve compression.



in another article i read that p minor syndrome actually stretches the bp, its not compressing the bp (vasc. compression different story)