THOUGHTS ON PAIN...
There are many sources of pain in the human body. From the chiropractic point of view, the muscular guarding patterns that develop to protect an injured body part are a common source of pain.
Pain felt by a person in one part of their body might NOT be the site of the problem! Pain can be remote from an injury, but related.
If I were to ask you to grab hold of something in your hand and grip it really hard, how long would it be before you began to develop pain in the muscles of the hand and fingers from the effort to grip? This same type of pain can occur around some vital component of the body that is about to come apart or is displaying dysfunctional or unstable motion patterns. The body is going to read these abnormal conditions as a signal of impending disaster for that area. The sensory apparatus, the nerve endings in the tissues, are delivering distress messages to the spinal cord. (See illustration P-1. - coming soon).
The human body is genetically pre-programmed for self-preservation and survival. Joint failure - such as a shoulder coming apart - represents a serious threat to survival. So the body will institute mechanisms to protect an injured joint, making muscle groups rigid and restricting a limb from certain motions. It's the same with the vital cavities of the spinal canal, pelvis and rib cage (I cover these in the other sections). The neurological structures in the joints will constantly send messages to the spinal cord, where they are transferred by reflex out to the muscles.
To protect the compromised area, some muscles will be required to become hard in order to reduce the range of motion of the different body components in the area. The insertions that attach a muscle's tendon into the cortex ( outer layer) of the bone are called Sharpey's Fibers (see illustration P-2, coming soon), and they can become strained, inflamed, and painful.
-William Ruch, D.C.