‘Clunking’ Shoulders – Part I
Clunking or clicking shoulder is a common complaint with swimmers where the shoulder 'clicks' when under strain. It is also common to other sports where the overhead arm motion is thrown repetitively with force like badminton, tennis and cricket bowlers. Inflammation is a symptom, not a cause. This shoulder condition is often misdiagnosed as a rotator-cuff impingement or tendinitis (inflammation). But this is not entirely accurate as rotator-cuff impingement is simply a symptom, not the cause of the problem. You will still need to find out what is causing the inflammation in the first place.
Rotator-cuff inflammation can be caused by a damaged or diseased part of the shoulder like a torn muscle or cartilage (see Bankart Lesions) or growths like bone spurs which bite into the muscles.
However, often the rotator-cuff inflammation is caused by the inherent instability of the shoulder joint. To put it plainly, the shoulder joint is 'loosely' held in place. The shoulder (glenol-humeral) joint may be loose is several directions (multi-directional instability) or loose is a specific direction (uni-directional instability).
In multi-directional instability (MDI), excessive movement of the head of the humerus (the 'ball' end of the bone in your arm) causes it to scrap against the cartilage that helps hold the shoulder joint together (the labrum). Over time, this scrapping wears out the cartilage and the tendons nearby. The 'clunking' sound comes from the head of the humerus popping in and out slightly from the shoulder joint. MDI arises due to a laxity in the shoulder capsule and is often genetic in nature. World class swimmers for example tend to have very loose joints (hyper-mobile) which gives them the ‘extra’ range of shoulder movement.
Uni-directional instability (UDI) is more common for overhead throwing sports like tennis and cricket bowlers and tends to appear in one arm. The most common direction is for the humerus head to move forward. Unlike multi-directional instability which has genetic dispositions, uni-directional instability is caused by a few key muscles losing control of the joint and holding it stable. In most cases, it is the muscle holding the head of the humerus (subscapularis) allowing the shoulder to roll forward excessively, stretching the shoulder joint. Again, like in the case of MDI, the cartilage wears out and nearby tendons get impinged or pressed on.
Is it MDI or UDI?
An experienced sports physician or sports physiotherapist will be able to do tests that will confirm which diagnosis best describes the problem.
What can we do in the short-term?
If the athlete still needs to compete or has a competition coming up soon, short term measures such as massage and trigger-point release to reduce pain from the rotator-cuff inflammation, mobilize the surrounding joints. We will also work with the coach for a training load reduction. Focusing on quality rather than on quantity. Athlete education is crucial here. The athlete must understand the underlying cause of the problem.
In the long-term, we need to correct the issue of the instability by improving the muscular control of the joint and overall body stability. Muscular control for stability involves both muscle activation as well as strength. It is important that the muscle activates at the right moment. Too often, the focus is on building the strength of the muscle but not the control of it. A strong muscle that does not activate during the crucial moment is not much better than a weak muscle. The muscle training work will focus on the key stability muscles, namely
- Transversus Abdominus for the trunk and overall body stability
- Lower Trapezius and Serratus Anterior for the scapula
- Subscapularis for the head of the humerus
We will look at the specific exercises for the muscle training work targetting at the three muscles mentioned above in Part II.
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