Note: this is the second article in our series on Shoulder Injuries in American Sports. Read the first part here.
In part 1, we talked about the five stages of shoulder mobility that many people go through in life. Now let’s discuss the why in all of this. Why do our shoulders break down over time?
Shoulder Physics & Physiology
As adults we do the same thing most days mixed in with a little exercise and physical work on the weekends. As the years pass, we fall into a pattern of slow mobility and functional strength loss. We are no longer climbing trees and hanging from monkey bars and thus creating a potentially traumatic situation when we enter these realms with too much speed or too much of a load. As well, many of the sports that we Americans like are inherently traumatic to the shoulder joint. A study by the Boston Red Sox team physicians in 1985 assessing their pitching staff with high speed cinematography noted angular velocities with throwing up to 9198 deg/sec with internal rotation as well as peak accelerations 600,000 deg/sec sq.
Our shoulders respond to trauma via a classic fight or flight mechanism. Millenniums ago this was the optimal way to solve a problem. The joint would stiffen following trauma and was allowed to rest and potentially heal. There may be functional impairment thereafter, but usually the pain would resolve. Life spans were shorter and others were around to take over one’s duties. This is no longer the situation. 90-year-olds are hitting golf balls and cross country skiing. We can no longer rely on these antiquated means of solving a shoulder joint injury.
Micro & Macro Shoulder Trauma
From a physiological perspective, as we subject our shoulders to micro (recurring overuse i.e. throwing sports) and macro (i.e. blunt impact) trauma over the course of a lifetime, ligamentous structures about the shoulder tend to tighten in order to protect, noting further regression as we tend to work more than we play. As we age, we challenge the joint less frequently from a strength perspective and tend to get weaker.
Both of these issues lead to changes in the functional mechanical movement patterns of the shoulder joint. Liken it to driving the car down the road with the breaks on (see our previous article on how your shoulder is like a car). Sooner or later there are going to be issues as noted in the above classic shoulder regression. This pattern is accelerated with the incidence of macro trauma.
The pathological process first involves soft tissues (unless there is a traumatic fracture) within the joint, followed by wear to cartilaginous and ultimately bony tissue. This correlates to the phases as follows:
- Phase 1: bursitis, tendonitis, muscular strain
- Phase 2: chronic bursitis, tendonitis, early phase cuff weakness
- Phase 3: initial (mild) rotator cuff tearing due to chronic tendon changes
- Phase 4: early degenerative change about juncture of shoulder blade (scapula) and collar bone (clavicle) or ball and socket with mild to moderate rotator cuff tearing
- Phase 5: mild to severe rotator cuff tearing and mild to severe osteoarthritis
Shoulder Treatment at Each Phase
80-90% of shoulder injuries, especially those addressed in the earlier phases can be solved in a conservative fashion. For phases 1-4 a conservative program of care will first stabilize the pain and allow soft tissues to heal. This is followed by the restoration of functional mobility and finally progress with strengthening patterns that become specific to the desired sport. This is specific to each individual and transitions into home exercises and return to play activities.
The crucial component is grasping the reality of the shoulder joint status, implementing the appropriate care and adjusting physical activities to prevent short or long term re-injury. A paradigm shift for many middle aged males with respect to their physical capabilities must occur, and this is quite difficult but necessary to have a positive outcome.
We work hard over a lifetime to one day retire and enjoy a lifestyle of positive leisure which often includes physical activity. As well, personal safety (i.e. being able to correct a fall onto an extended arm with minimal subsequent involvement) helps ensure a quality of life that we all desire. Proactive intervention with a positive mindset as I have described above is crucial to accomplishing a return to sport and other lifetime goals.