Thrower’s Shoulder

Thrower’s shoulder describes complaints caused by functional and structural changes to the shoulder joint in the course of overhead and throwing sports such as swimming, handball, volleyball or tennis.

Throwing movements can be divided into three phases: In the first phase of a throwing movement, the arm is spread out and rotated outwards as far as possible. The arm is then moved forward in the so-called acceleration phase. This is followed by the deceleration phase, which is associated with a high load on the shoulder joint, particularly the posterior parts of the joint capsule. Repetitive throwing movements therefore lead to enormous load peaks in the shoulder joint as well as to adaptation processes in order to enable the best possible throwing. These associated changes can lead to structural injuries in the shoulder joint over time.

The main symptoms of thrower’s shoulder can be:

• Shoulder pain on exertion
• Restricted movement (especially internal rotation)

Typically, those affected suffer from load-dependent shoulder pain, which occurs particularly during throwing movements and increases over time. In addition, the high load on the posterior joint capsule leads to shrinkage and thickening of the capsule at this point, which results in reduced internal rotation of the shoulder. This phenomenon is known as glenohumeral internal rotation deficit (GIRD). Due to the maximum external rotation during throwing movements, there is a simultaneous stretching of the anterior joint capsule and thus an excessive external rotation capacity compared to the opposite side.

The symptoms can lead to a temporary inability to exercise, which significantly reduces the quality of life of those affected.

Throwing athletes frequently experience shoulder injuries, with the rotator cuff and labrum being particularly vulnerable. These include degeneration of the rotator cuff tendons, often with partial tears. SLAP lesions (tears of the labrum), posterior impingement of the rotator cuff, and anteroposterior shoulder instability.

1. Rotator Cuff Degeneration and Tears:

Rotator cuff tendons, which help stabilize and rotate the shoulder, can degenerate and develop tears over time. These tears can be partial, meaning they don’t completely sever the tendon, and are often seen in the intra-articular (within the joint) space. In younger individuals, acute tears can result from trauma, while in older individuals, degeneration is more common.

2. SLAP Lesions:

SLAP (Superior Labrum Anterior to Posterior) lesions involve tears of the labrum, a ring of cartilage that surrounds the shoulder socket (glenoid). These tears often occur at the attachment site of the long head of the biceps tendon. SLAP lesions can be caused by acute trauma or chronic wear and tear.

3. Posterior Impingement:

Posterior impingement occurs when the supraspinatus tendon (part of the rotator cuff) gets trapped between the humerus (upper arm bone) and the glenoid at the back of the shoulder. This can lead to pain and inflammation, especially during overhead activities.

4. Shoulder Instability (APIT):

Anteroposterior instability (APIT) refers to excessive movement of the humerus within the glenoid socket in the forward-backward direction. In throwing athletes, this can be caused by tears in the rotator interval (a region between the supraspinatus and subscapularis tendons) and the articular surface of the infraspinatus. This instability can lead to pain, a feeling of looseness in the shoulder, and difficulty controlling throwing motions.  

Most of these injuries are due to overuse and throwing past muscle fatigue. When athletes don’t allow the shoulder enough time to rest, they put themselves at risk of injuries.

The orthopedic surgeon will ask you about your complaints in a detailed consultation. This is followed by a thorough examination of the shoulder joint with regard to the range of motion and accompanying structural damage. Typically, limited internal rotation and increased external rotation are noticeable. A medical history and physical examination are usually sufficient to make a diagnosis.

Imaging procedures such as ultrasound and/or magnetic resonance imaging (MRI) are used to rule out structural damage. In most cases, the typical changes in the joint capsule (contraction of the posterior parts, stretching of the anterior parts) are also visible.

An early and accurate diagnosis of the problem is always the “key” to a correct, successful, and definitive treatment.

Conservative (Non-surgical) Treatment

If the condition is diagnosed early, it is possible—with specialized stretching and physiotherapy programs—to prevent further progression of the problem. Changing the training method and improving technique are equally important factors.

Surgical Treatment

If symptoms persist for a long time or the conservative (non surgical) treatments fail, then surgical treatment is absolutely necessary. Shoulder arthroscopy can address various joint injuries like SLAP lesions, shoulder instability, or rotator cuff tears.

Thrower’s shoulder, a condition common among overhead-throwing athletes, is characterized by a range of symptoms that limit shoulder functionality due to repetitive throwing motions.

Early and accurate diagnosis is crucial for effective treatment.

Please, visit the orthopedic surgeon Dr. Panagiotis Pantos for immediate management of your problem.