An estimated 20% of injuries to upper extremities involve the elbow, and approximately 10% involve the wrist; the majority of these injuries are overuse type of injuries.1–4 Sports in which overuse injuries of the elbow and wrist in an adolescent occur are listed in Table 23-1. Also, in racquet sports (such as tennis or badminton) and in gymnastics, the elbow is subject to significant stress resulting in overuse injuries.
Table 23-1. Sports in Which Overuse Injuries of Elbow and Wrist Are Seen ||Download (.pdf)
Table 23-1. Sports in Which Overuse Injuries of Elbow and Wrist Are Seen
Relatively more common
Racquet sports (e.g., tennis, badminton)
Throwing sports (e.g., baseball, softball)
Relatively less common
Definitions and Epidemiology
Repetitive throwing action can result in multiple injuries of elbow and are summarized in the Table 23-2.5–11 Collectively, varying degrees of these injuries represent the “little leaguer elbow,” which is a less preferred and nonspecific term.
Table 23-2. Elbow Injuries Associated with Throwing ||Download (.pdf)
Table 23-2. Elbow Injuries Associated with Throwing
Medial epicondyle apophysitis
Medial epicondyle avulsion
Ulnar collateral ligament sprain
Elbow flexion contractures
Olecranon stress fracture
Osteochondritis dissecans of the capitellum
Intra-articular loose bodies
The secondary ossification centers around the elbow include the capitellum, radial head, medial epicondyle of the humerus, trochlea, olecranon, and lateral epicondyle. These generally fuse between ages 14 and 17. Elbow injuries in athletes involved in throwing sports have been extensively studied, specifically for the pitcher in youth baseball.5,6,10 The motion of throwing (pitching) in baseball is characterized by a complex series of movements. This is divided into windup, cocking, acceleration, release, and follow-through phases (Figure 23-1). During each phase different structures are stressed resulting in different injuries. (Table 23-3). On the medial side of the elbow the medial collateral ligament, the immature (unfused) epicondyle, and the ulnar nerve are affected because of repeated traction. On the lateral side there is repeated impact at the radiocapitellar area, and posteriorly there is extension overload affecting mainly the triceps insertion, and olecranon.
Table 23-3. Mechanism of Throwing ||Download (.pdf)
Table 23-3. Mechanism of Throwing
Shoulder and Arm Movements
Primary Muscles Involved
Phase I. Windup (cocking phase)
Shoulder is abducted to 90 degree, hyperextended with extreme external rotation.
Scapula is clamped against the chest wall and slightly elevated.
Wrist is extended.
Anterior capsule. The head of the humerus is forced forward. If the anterior capsule is tight (such as in a professional pitcher) and the ...