The evaluation and treatment of musculoskeletal disorder
Arthritis
Degenerative arthritis (Osteoarthritis) is often the result of repeated impact to a joint over a course of years. Weight is a downward force, and impact (shock) is an upward force. The management of these opposing forces is of vital importance. Think of how many steps you take in a year, in a decade. Millions of steps. If you run, the number and force of impacts will be multiplied. This can also be true of downhills, stairs, and dance.
Effective shock absorption is actually shock dispersion. There is an ordered pathway in the design of our body to disperse these two forces with relatively minimal consequences.
As the ability of the body to hold itself together becomes compromised, we begin to torque and collapse in a slowly spiraling cycle of compromised function that can accelerate degenerative changes. The more compromised we become, the less capable we are of dispersing impact forces and the more compromised we can become.
The absorption of shock is degenerative not only for our body but even for machines, like your car. If the suspension system is compromised, subsequent shocks will be increasingly damaging to the suspension, and over time it will be increasingly more susceptible to subsequent shocks. Eventually, the entire vehicle can be affected.
A similar dynamic to that of weight vs. the impact ascending from the ground can occur in the upper body, especially for athletes and people in occupations like the building trades. For example, when a hammer strikes, there is a counter force that is absorbed by the body, not only in the wrist, elbow, and shoulder but also in the torso, neck, and lower body.
Workers and athletes frequently encounter these forces. Many arm motions, including hammering, throwing, and swimming, involve whole-body rotation as well as forward motion. For this reason, each of these activities can also involve the neck, back, hips, knees, and even the feet. Anything can affect everything.
Arthritis after injury
A 2017 New York Times article* reports a high risk of osteoarthritis (74%) approximately ten years after tearing a tendon or ligament. The article describes efforts to understand why this occurs:
“What researchers want to know is this: Why do these injuries precipitate arthritis? Is the answer a bone bruise that injures cartilage? Chemical changes that happen as the body tries to repair the injury? An intrinsic instability of the knee? And would surgical methods that more closely reproduce an individual’s original knee anatomy reduce the risk?”
* [“If you Tear A Knee Ligament, Arthritis is Likely To Follow in 10 Years”
Efforts to more closely reproduce the original anatomy can be important, and yet joints frequently become arthritic following surgical care because the lack of stabilization has not been addressed. A slight aberation in the resting tone of stabilizing structures can, over time, have significant consequences. Imagine flying on a jetliner with a few loose bolts. The bolts will tend to become increasingly loose over time, until the entire structure can fail.
Multiple and simultaneous factors can be at play in the development of arthritic degeneration after injury. There can be disruption to the gross anatomy, changes in the calibration of stabilizing tissues, secondary torsional and impact forces from the distortions of other joints, and, importantly, changes in the neurologic assignment of stabilizing function as the body moves and acts. Arthritis develops incrementally over years, due to factors not necessarily at the site of degeneration.
Anatomical predisposition to degeneration
It has been suggested that osteoarthritis is genetic. “My mother had her hip replaced and now I have to have my hip replaced.” Genetic factors can indeed predispose a person to degenerative arthritis. For example, congenitally shallow hip or shoulder sockets might make a person more susceptible to the forces and effects of activity. A genetic predisposition does not contradict the relationship between stabilization/impact forces and the body, it enhances it.
Something is going on. Something is always going on.