Can Poor Scapular Control Lead to a Labrum or a UCL Tear? You Bet

by Randy Sullivan
in blog

Throughout the pitching movement the stability of the scaps is incredibly important, but during the last few milliseconds as the ball is released, the ability to control the scapula becomes vital to the health and durability of the shoulder and the elbow. When a pitcher propels his arm forward, downward, and inward through ball release an entire team of scapular depressors and retractors must work together to resist long axis distraction of the humerus and elevation of the humeral head keeping the ball in the socket.  The scapular, thoracic and humeral stabilizers must work eccentrically, producing tension as the muscles elongate. In the gym, they call eccentric contractions, “negatives”. Eccentric muscle contractions produce about twice as much force as concentric contractions (when the muscle is producing tension while shortening). If the scapula-humeral stabilizers are not trained, they tend to surrender at ball release, like a guy losing a tug-of-war. That leaves one muscle, the long head of the biceps, solely responsible for eccentrically resisting long axis distraction, humeral head elevation, and terminal elbow extension.

Since the biceps tendon is attached to the labrum at the top of the shoulder, if the biceps is forced to bear thatlabrumscope burden alone, the eccentric pull on the labrum can tear it loose from the glenoid (the socket). The labrum is an important component to the stability of the shoulder joint.  Significant labrum tears usually result in surgery. According to one study, only 50% of pitchers who underwent a repair were able to return to prior level of competition.

biceps-long-head

Excessive eccentric biceps activity can also create a problem in the elbow. The primary supinator (palm facing up) of the forearm is the biceps muscle. Think of a muscle head in the gym supinating a dumbbell to get the full benefit of a biceps curl.

linear-decel     During a linear deceleration pattern, the elbow straightens (extends) fully resulting in a violent collision of the humerus on the ulna.   The biceps tendon tugs  eccentrically on the elbow to prevent this, which can impart a supination moment to the forearm. The primary stabilizers of the elbow that protect the UCL or “Tommy John” ligament are 4 muscles that flex the wrist, flex the fingers, and pronate the forearm (flexor carpi ulnaris, flexor carpi radialis, flexor digitorum superficialis, pronator teres).  Anatomically, these 4 muscles insert in a common tendon directly on top of the UCL.  When these muscles are activated, they  impart a  force on the elbow that shortens the UCL reducing the load by about 14%. When the forearm is supinated, these 4 critical elbow stabilizers cannot be activated. This leaves the UCL unprotected screen-shot-2016-10-14-at-10-46-44-amand vulnerable at ball release.

It only takes about 25 degrees of supination to inhibit the forearm muscles enough to take the UCL beyond its yield capacity. So to protect the UCL and the labrum, the scapular muscles and the rotator cuff must be trained to eccentrically resist long axis distraction and humeral head upward translation at the end of the movement – while the shoulder joint is being distracted immediately before, during, and after ball release. If we can train those muscles to stay in the fight and not  surrender at ball release, the biceps can be quieted, thereby removing dangerous forces on the labrum and the UCL and SHUTTTING THE BICEPS DOWN!!!!!

To optimally support and protect the labrum and the UCL, the rotator cuff and the periscapular musculature must be trained to maintain coordinated control and stability of the humeral head, keeping it in the center-packed position in the glenoid. The center packed position is the optimal position of a joint, which allows for the most effective movement patterns to occur.  By maintaining the close packed position and delaying internal rotation of the humerus until after the elbow reaches the last 20 degrees of extension, the force and magnitude of the ball release can be maximized while decreasing the risk of injury in the shoulder or elbow.

Training the rotator cuff and periscapular muscles to eccentrically control the humeral head and the elbow is vital to injury risk reduction. However, to ensure specificity and translation of the training effect to actual game performance, these muscles must be trained to maintain shoulder and elbow joint integrity while they are in distraction and at high speed.

How can this be accomplished?

That’s what ScaptivationTM is all about.

ScaptivationTM is a progressive training system for establishing mobility, stability, motor control and coordination of the scapular powerhouse to create bulletproof shoulders and elbows for the high velocity throwing athlete. 

Our recently published book ScaptivationBulletproofing The Next Generation of Elite Power Arms comes with a customized thumb drive containing video demonstrations of it all.

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Get your copy now by clicking here.

It’s like having kevlar coating on your arm!

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