Shoulder Injury Prevention

Shoulder impingement and labral tears are the most common injuries among overhead sports, like baseball and volleyball. During the overhead throw or swing, the powerful latissimus and pectoral muscles accelerate the motion. When the accelerating momentum is greater than the athlete’s ability to decelerate and stabilize the shoulder’s forceful swing, microtrauma can occur in the shoulder’s related tissue. Repetitive microtrauma can lead to tissue damage and tears; most commonly labral and rotator cuff tears.

Factors that predispose the shoulder to injuries are neuromuscular imbalances, improper technique, excessive practice volume and intensity, inadequate recovery, unbalanced nutrition, and overall poor fitness level.

This article addresses the impacts of neuromuscular imbalances, adequate strength and range of motion of the shoulder complex. As mentioned above, repetitive use of a specific movements leads to maladaptive compensations. Over time, if not properly addressed, the throwing muscles such as the pectorals, latissimus and terres major become overactive and shortened. On the other hand, their functional antagonists lengthen and weaken, changing the functional biomechanics of the shoulder. This maladaptive compensation increases the risk of injuries.

Physical traits of these faulty compensations would be rounded/internally rotated shoulders(B,C,D), head forward posture, abducted scapula(A), and slouching down posture. These characteristics are often accompanied by scapula dyskinesis(E). This is a dynamic compensation where the shoulder blade wings off the ribcage when the shoulder moves up and down. 

Everyone has different overtraining thresholds. Therefore, the term overtraining is only relative to the degree of neuromuscular imbalances, training experience, as well as strength and conditioning level. The greater the velocity of the throw or swing of the shoulder, the more likely it is to cause shoulder pain. Studies also show that fatigue of the rotator cuff muscles is another contributor of shoulder instability leading to injuries.

During athletic activities or any functional movements, the human body works as a unit. Each segment of the body should move within a functional degree of range of motion for the body to move optimally. Areas away from the shoulder, like the thoracic spine, should have optimal range of motion and alignment in order for the shoulder blade to glide and stabilize. The ankle flexibility is important for baseball pitchers for a more effective swing. A disruption of the normal range of motion anywhere in the body can affect the flow of the whole kinetic chain. For example, a baseball pitcher with decreased ankle range of motion is more prone to shoulder injuries than their more flexible counterparts.

For an athlete, their health is very important. If you are injured or in pain you cannot practice. If you can’t practice you won’t play. Here are some of the things you can do:

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• Be proactive and monitor the volume and intensity of your swings, pitches, spikes, swim labs etc. This way you have an overtraining threshold baseline. Remember each individual is unique. Discuss with your coach to undulate practice volume intensities, incorporating resting days, take into consideration age, experience, skill level, strength and neuromuscular efficiency.
• Warm up to properly address range of motion and activate appropriate muscle groups and synergies, followed up by sports specific drills—this would be the most effective sequence prior to practice.
• Incorporate an injury prevention program during off season and in your strengthening routine throughout the year.
• Lastly, seek for early onset symptom intervention. This means to ask to see your healthcare professional or your sports medicine professional to guide you through before it becomes a big issue.

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Below is a sample injury prevention program you can perform. If you have any questions about this article and this program feel free to email me at [email protected]

Citations

1. Hamano, N., Shitara, H., Tajika, T., Ichinose, T., Sasaki, T., Kuboi, T., Shimoyama, D., Kamiyama, M., Miyamoto, R., Endo, F., Nakase, K., Kobayashi, T., Yamamoto, A., Takagishi, K., & Chikuda, H. (2021). Relationship between the lower limb function and shoulder and elbow injuries          in elementary school baseball pitchers. Progress in Rehabilitation Medicine, 6(0). https://doi.org/10.2490/prm.20210015
2. Kobayashi, E., Matsumoto, H., Hayashi, I., Osaki, M., & Hagino, H. (2020). Age-related changes in muscle elasticity around the shoulder joint in young male baseball players: A prospective longitudinal study. Journal of Orthopaedic Science, 25(4), 582–587. https://doi.org/10.1016/j.jos.2019.06.017
3. Zaremski, J. L., Pazik, M., Vasilopoulos, T., & Horodyski, M. (2024). Workload risk factors for pitching-related injuries in high school baseball pitchers. The American Journal of Sports Medicine. https://doi.org/10.1177/03635465241246559
4. Dale, R. B., Kovaleski, J. E., Ogletree, T., Heitman, R. J., & Norrell, P. M. (2007). The effects of       repetitive overhead throwing on shoulder rotator isokinetic work-fatigue. North American journal of sports physical therapy : NAJSPT, 2(2), 74–80.