The UCL is important because it stabilizes the<unk>  from being abducted. If intense or repeated bouts of valgus stress occur on the UCL,<unk>  will most likely transpire. Damage to the<unk><unk><unk>  is common among baseball pitchers and javelin throwers because the throwing motion is similar. Physicians believe repetitive movements, especially pitching in baseball, cause adolescents' UCL<unk> es. Furthermore, physicians have stated that if an adolescent throws over 85 throws for 8 months or more in a year, or throw when exhausted, the adolescent has a significantly higher risk of succumbing to a UCL surgery. Gridiron football, racquet sports, ice hockey and water polo players have also been treated for damage to the<unk><unk><unk> . Specific overhead movements like those that occur during baseball pitching, tennis serving or volleyball spiking increase the risk of UCL<unk> . During the cocking phase of pitching, the shoulder is horizontally abducted, externally rotated and the<unk>  is flexed. There is slight stress on the UCL in this position but it increases when the shoulder is further externally rotated. The greater the stress the more the UCL is stretched causing strain. During the overhead throwing motion, valgus stress on the medial<unk>  occurs during arm cocking and acceleration. The initiation of valgus stress occurs at the conclusion of the arm-cocking phase. In the transitional moment from arm cocking to arm acceleration, the shoulder vigorously rotates internally, the forearm is in near full supination, and the<unk>  flexes from 90° to approximately 125°. From late cocking to ball release, the<unk>  rapidly extends from approximately 125° to 25° at ball release. This causes tremendous valgus stress and tensile strain on the UCL.<unk> es to the<unk><unk><unk>  are believed to result from poor throwing mechanics, overuse, high throwing velocities, and throwing certain types of pitches, such as curveballs. Poor mechanics along with high repetition of these overhead movements can cause irritation, micro-tears or ruptures of the UCL. Kinetic chain dysfunction due to poor lower extremity strength, core strength and stability can be associated with UCL<unk> es as well as capsular stiffness in glenohumeral internal rotation deficit (GIRD), and scapular dyskinesis.<unk> es to the<unk><unk><unk>  in baseball players are rarely due to one-time, traumatic events. Rather, they are more often due to small chronic tears that accumulate over time.
Ulnar collateral ligament injury of the elbow
Ulnar collateral ligament injury of the thumb
Metatarsophalangeal joint sprain
Iliotibial band syndrome
Olecranon bursitis
Patellar tendon rupture
Plantar calcaneal bursitis
Elbow fracture