One of the most unique and explosive motions in sports is the overhead throwing motion. Throwing a baseball, softball, or football overhead places extremely high stresses on the shoulder and elbow. In order to put velocity into a thrown ball, power is generated from the ground with the lower body, transferred through the core into the arm, ultimately propelling the ball forward.
There are several bodily areas throughout that chain, called the kinetic chain, that can become injured. The most common areas of injury for a thrower are the elbow or shoulder. The most common throwing injuries to the shoulder and elbow include:
Elbow:
• Epicondylitis or “tennis elbow”
• Medial epicondyle apophysitis or “Little League elbow”
• Forearm muscle strains
• UCL (ulnar collateral ligament) or “Tommy John ligament” injuries
• Ulnar nerve neuritis
• Valgus extension overload
Shoulder:
• SLAP (superior labrum anterior to posterior) labrum tear
• Rotator cuff injury
• Posterior impingement
• Injury to the growth plate “Little League shoulder”
Most throwing injuries are a result of a weak link somewhere in the kinetic chain. That weak link then places increased stress on the structures downstream. The weak link could be improper mechanics, a lack of strength, lack of conditioning, or lack of motion in one of the areas within the chain. For example, many throwing elbow injuries are often caused by improper mechanics or limitations in the shoulder that then place increased stress on the elbow.
As an athlete, gaining knowledge about throwing injuries is only half the battle — the other half lies in understanding and implementing effective measures to prevent these injuries. Throwing injury prevention strategies are crucial for ensuring longevity in the sport and safeguarding athletes’ physical health. These strategies are included below.
1. The first step to preventing throwing injuries is ensuring proper mechanics. Seek training from qualified coaches who can teach you how to generate power and velocity from the ground with your legs, transfer it efficiently and safely through your core, and into your arm and the ball.
2. The second step is proper conditioning. This includes arm conditioning with proper throwing programs to slowly build up and condition the muscles used in the throwing motion. This is why spring training for Major League Baseball takes six weeks — and most major leaguers begin their conditioning well before spring training starts. You set yourself up for injury if you forgo this process and jump into game speed with max effort throwing before your body is ready and conditioned to do so.
3. The third step is having a proper arm care routine. This includes strengthening/conditioning the muscles of the arm as well as stretching. Strengthening the arm includes strengthening the muscles around the scapula (shoulder blade) which are responsible for moving the shoulder blade and keeping proper posture throughout the throwing motion. It’s also important to strengthen the rotator cuff muscles which are small muscles that help stabilize and move the shoulder throughout its range of motion. These muscles need to be intentionally strengthened. The forearm muscles also need to be strengthened and conditioned — especially the flexor/pronator muscles on the medial (inside) elbow and forearm. The flexor/pronator muscles are the main stabilizer of the medial elbow during the throwing motion. The back-up stabilizer to the medial elbow is the UCL or “Tommy John ligament.” When the flexor/pronator muscles begin to tire, more stress is placed on the UCL making it more vulnerable to injury.
Stretching for the throwing arm is focused mainly on the shoulder. Within the shoulder joint, throwing is an incredibly violent maneuver. In order to put velocity on a thrown ball, the shoulder has to externally rotate (the hand and ball rotates behind you) beyond anatomical norms into the cocked position, before explosively rotating forward when you release the ball. In order to accommodate and allow for this incredible amount of external rotation, the structures in the anterior (or front) of the throwing shoulder stretch out. With this increased flexibility in external rotation, however, comes increased tightness in the posterior (or back) of the shoulder. This results in a loss of internal rotation. So, a shoulder that has adapted to throwing will have increased external rotation and decreased internal rotation compared to a non-throwing shoulder.
Unfortunately, over time, this adaptation can begin causing significant injuries and pain if left unchecked. When the difference of internal rotation between the throwing shoulder and non-throwing shoulder becomes greater than 20 to 25 degrees, known as GIRD (Glenohumeral Internal Rotation Deficit), it can begin causing impingement on the labrum and biceps tendon causing pain, SLAP labrum tears, and/or impingement pain and injury to the rotator cuff. Proper arm care stretching is focused on stretching the back of your shoulder to increase your internal rotation and prevent it from becoming 20 to 25 degrees different than your non-throwing shoulder.
While athletes may pride themselves on handling pain, the old saying “no pain, no gain” is often bad advice for throwers. Any throwing athlete knows arm soreness is a normal part of throwing. However, sharp pain while throwing, or any pain that does not improve after few days of rest is not normal and you should be evaluated by a sports medicine specialist who understands the throwing motion. Often by intervening early and applying some of these strategies you can prevent further damage and avoid significant loss in playing time.
by John M. Kunkel, D.O.
UPMC Orthopaedic Care
John Kunkel, D.O., is a sports medicine orthopaedic surgeon with UPMC Orthopaedic Care and sees patients at 1201 Grampian Blvd., Williamsport. For more information about UPMC Orthopaedic Care and sports medicine services in north central Pa., visit UPMC.com/OrthoNCPA or call 570-321-2020.
