The musculoskeletal system is the means whereby we act out and express our human existence - 'the primary machinery of life' is what osteopathy's greatest researcher Irwin Korr1 called it. While medically speaking the musculoskeletal system may lack the glamour and fascination of vital organs and systems the fact is that the cardiovascular and neuroendocrine and digestive (and other) systems and organs exist only to service this great machine through which we live and function.
It is by means of our musculoskeletal system that we perform tasks, play games, make love, impart treatment, perform on musical instruments, paint and, in these and a multitude of other ways, interact with each other and the planet.
The musculoskeletal system is also the greatest energy user in the body as well as being one of our primary sources of pain, discomfort and disability and it is vastly complex with a host of interacting and interdependent elements.
Korr's words2 reminds us:
"The spinal cord is the keyboard on which the brain plays when it calls for activity or for change in activity. But each 'key' in the console sounds, not an individual 'tone', such as the contraction of a particular group of muscle fibres, but a whole 'melody' of activity, even a 'symphony' of motion. In other words, built into the cord is a large repertoire of patterns of activity, each involving the complex, harmonious, delicately balanced orchestration of the contractions and relaxations of many muscles. The brain 'thinks' in terms of whole motions, not individual muscles. It calls selectively, for the preprogrammed patterns in the cord and brain stem, modifying them in countless ways and combining them in an infinite variety of still more complex patterns. Each activity is also subject to further modulation, refinement, and adjustment by the afferent feedback continually streaming in from the participating muscles, tendons, and joints."
The information fed back to the CNS and brain, reflects the steady state of joints, the direction and speed of alteration in position of joints, together with data as to the length of muscle fibres, the degree of load being borne, along with the tension this involves.
Korr3 discusses a variety of insults which may result in increased neural excitability; the triggering of a barrage of supernumery impulses, to and from the cord, and also what he terms 'cross-talk', in which axons may overload and pass impulses to one another directly; muscle contraction disturbances, vasomotion, pain impulses, reflex mechanisms, disturbances in sympathetic activity, all may result from such activity, due to what might be relatively slight tissue changes.
He summarises thus, 'These are the somatic insults, the sources of incoherent, and meaningless feedback, that causes the spinal cord to halt normal operations and to freeze the status quo in the offending and offended tissues (causing spasm for example). It is these phenomena that are detectable at the body surface, and are reflected in disorders of muscle tension, tissue texture, visceral and circulatory function, and even secretory function.’
Selye4 called stress the non-specific element in disease production. In describing the relationship between the General Adaptation Syndrome (GAS) i.e. alarm reaction, resistance (adaptation) phase followed by the exhaustion phase (when adaptation finally breaks down) which affects the organism as a whole - and the Local Adaptation Syndrome (LAS) which affects a specific stressed area or the body. He demonstrated that stress results in a pattern of adaptation, individual to each organism and also showed that when an individual is acutely alarmed, stressed, aroused - homeostatic (self-normalising) mechanisms are activated. This is the alarm element of Selye's general and local adaptation syndromes.