Here are the basics.  Our fascia (a.k.a. one type of connective tissue) condenses in three dimensional space and gets stuck that way.  I refer to it as "pattern," while other may may call them muscle knots, adhesions, etc.  Pattern in the fascia can cause all sorts of issues.  We call it something different depending on where it is happening in the body.  If it happens in the head it can cause headaches, tinnitus, and jaw pain (TMJD).  If it happens in the neck (cervical spine), it can cause a stiff neck, kink in the neck, neck pain, torticolis, and also possibly thoracic outlet syndrome.  If it happens in the shoulder it can cause thoracic outlet syndrome, stiff or frozen shoulder, rotator cuff issues.  If it happens in the forearm it can cause carpal tunnel syndrome, wrist pain, hand/palm pain, even finger pain.  If it happens in the rib cage (aka thoracic spine)... you are starting to get the idea, aren't you?  Pattern happens everywhere in the body.

​

Pattern in the fascia limits our movement, including the internal movement that happens within our bodies as well.  Your arm is made up of lots of tissue and fibers.  All of that has to be able to stretch, such that it can extend and expand outward as you reach your arm out to grasp for something with your hand. If pattern is present in the arm, the arm's function or ability to move is limited compared to when the tissue is free of pattern.

To learn even more about fascia, read the Structural Integration page.