Elbow Throwing Injuries

The elbow is a hinge joint formed by three bones: the humerus (upper arm bone), the ulna (the larger of the two forearm bones), and the radius (the smaller forearm bone). These bones are connected by ligaments, which provide stability to the joint, especially during high-force movements like throwing.

One of the most important elbow stabilizers in throwing athletes is the ulnar collateral ligament (UCL). This ligament runs along the inside of the elbow and resists the strong outward (valgus) forces that occur during the late cocking and acceleration phases of the throwing motion. Other soft tissue structures around the elbow include the flexor-pronator muscles, which help stabilize the elbow and assist in wrist movement, and the ulnar nerve, which runs along the inner elbow and can become irritated or compressed in throwing athletes.

The high velocity and repetition of throwing place significant strain on the elbow, often leading to specific overuse injuries. The most common throwing-related elbow injuries include:

• Ulnar collateral ligament (UCL) injuries are among the most well-known elbow injuries in throwing athletes. The ligament may become stretched, frayed, or torn, causing pain inside the elbow. Athletes may notice a decrease in throwing velocity or control and may describe a “pop” or sharp pain during a throw.
• Flexor-pronator muscle strain: These muscles, which run along the inner forearm and attach near the elbow, help stabilize the joint. Overuse or improper mechanics can lead to small tears in the muscle-tendon unit, causing inner elbow pain and reduced grip strength.
• Medial epicondylitis (commonly called golfer’s elbow): This condition involves inflammation or degeneration of the tendons that attach to the bony bump inside the elbow. It often results in wrist flexion or gripping pain and is frequently seen in golfers and throwing athletes.
• Ulnar nerve irritation (cubital tunnel syndrome): The ulnar nerve runs through a groove in the inner elbow. Repeated throwing can cause the nerve to become irritated, leading to numbness or tingling in the ring and little fingers, as well as weakness in the hand.
• Valgus extension overload: This condition involves the back of the elbow, where the olecranon bone can become irritated or compressed as the elbow snaps into full extension. Athletes may feel pain in the back of the elbow and sometimes notice swelling or locking.

The primary cause of throwing athletes is repetitive stress. The motion of throwing, especially in sports like baseball pitching, generates extremely high forces through the elbow, particularly during the late cocking and acceleration phases. Over time, this constant strain can damage the ligaments, tendons, and muscles that stabilize the joint.

Several risk factors can increase the likelihood of injury:

• Overuse: Throwing too often or with too little rest between sessions can overwhelm the body’s ability to recover, leading to microtrauma and overuse injuries.
• Poor mechanics: Incorrect throwing technique can place excess strain on the elbow. Even small arm angle or body positioning flaws can result in cumulative damage over time.
• Insufficient strength and flexibility: Weakness in the shoulder, core, or forearm muscles can force the elbow to take on more stress than it should. Limited flexibility in the arm or shoulder can also alter mechanics, increasing injury risk.
• Early specialization: Young athletes who play only one sport year-round are at higher risk because they use the same muscles repeatedly without cross-training or rest.
• Growth plate vulnerability: In younger athletes, the bones have not fully matured, and the growth plates are more susceptible to stress-related injuries such as “Little League elbow,” a condition affecting the growth plate inside the elbow.

When a throwing athlete develops elbow pain, a thorough clinical evaluation is the first step in diagnosis. The provider will begin with a detailed history, asking about the athlete’s sport, position, training schedule, symptoms, and any recent changes in performance or comfort.

A physical exam will follow, focusing on tenderness, range of motion, and strength. Specific tests may reproduce symptoms or stress the ligaments and tendons to identify the source of pain.

In many cases, imaging is used to confirm the diagnosis:

• X-rays can identify bone injuries, spurs, or signs of stress in the elbow.
• MRI scans are especially helpful for visualizing soft tissues, such as the UCL or surrounding muscles and tendons.
• Ultrasound may be used for dynamic imaging of tendons and nerves, allowing the doctor to see movement in real-time.
• Nerve studies may be ordered if nerve irritation is suspected, particularly when numbness or weakness occurs.