The shoulder isn’t just a simple joint. In fact, the shoulder is a complex of multiple joints and muscle groups that is incredibly mobile and allows you to generate force to throw a baseball or spike a volleyball.
To maximize your performance and reduce the risk of injury, it’s imperative that you understand how the shoulder complex functions.
The Shoulder is Designed for Motion
To better understand the function of the shoulder complex, picture a golf ball sitting on a tee. This is the glenohumeral (GH) joint’s function by design—a full range of motion through many planes but little structural stability.
The rotator cuff muscles are responsible for providing stability (keeping the golf ball on the tee) to the gleno-humeral joint.
Stabilizing the joint is easy when your arm is immobilized. However, it requires a lot more work when you’re throwing a ball or swinging a bat.
Furthermore, the mobility and stability of the shoulder joint will be compromised if there is a weakness or imbalance in the rotator cuff muscles.
Microtrauma Can Lead to Rotator Cuff Injuries
The rotator cuff consists of four muscles that pull the humeral head (ball) into the glenoid (socket) during arm movement.
Similar to how the rotator cuff muscles correlate with the glenohumeral joint, deficiencies in other areas of the shoulder complex can put added stress on the rotator cuff.
The repetitive microtrauma that accumulates over weeks, months and even years can lead to injury. This is common with baseball and volleyball players and even CrossFitters. The pain starts slowly and builds up over time.
It’s not just overuse that causes microtrauma to the shoulder. A common problem is that athletes continue to perform after they are fatigued, exceeding their ability to control motion through the shoulder complex. This is why youth baseball leagues and even Major League teams use pitch counts.
Whether throwing, hitting or pressing overhead, doing so when you’ve lost the ability to control the kinetic chain can lead to injury.
Function is Key
Shoulder treatments will help reduce pain and swelling when dealing with an injury, but this is where many athletes fail at rehabilitation. They “chase the pain,” treating only the area that’s hurt. It’s a quick fix to relieve the pain, but it fails to address the source of the problem.
Instead, you’re more likely to eliminate the risk of re-injuring your shoulder if you focus on improving the function of the entire kinetic chain. This requires a greater understanding of biomechanics, physiology and motor control, and should focus on targeting areas of the body that you may not think directly correlate to the shoulder.