Shoulder Injuries

SLAP/ Labral tear: SLAP lesion is an injury to the glenoid labrum (fibrocartilaginous rim attached around the margin of the glenoid cavity). Tears of the superior labrum near to the origin of the long head of biceps were first described among throwing athletes.

A total of four types of superior labral lesions involving the biceps anchor have been identified. Type I concerns degenerative fraying with no detachment of the biceps insertion. Type II is the most common type and represents a detachment of the superior labrum and biceps from the glenoid rim. Type III represents a bucket-handle tear of the labrum with an intact biceps tendon insertion to the bone. Finally, Type IV lesions, the least common type represent an intra-substance tear of the biceps tendon with a bucket-handle tear of the superior aspect of the labrum. The Type II SLAP lesions have been further divided into three subtypes:

Type V: a Bankart lesion that extends superiorly to include a Type II SLAP lesion.
Type VI: is an unstable flap tear of the labrum in conjunction with a biceps tendon separation.
Type VII: a superior labrum and biceps tendon separation that extends anteriorly, inferior to the middle glenohumeral ligament.

There are a lot of different mechanisms of injury that can result in a SLAP lesion. The following causes have been found:

• repetitive throwing,
• hyperextension,
• a fall on an outstretched arm,
• heavy lifting,
• Direct trauma.

Symptoms:

• sensations of painful clicking and/or popping with shoulder movement
• loss of glenohumeral internal rotation range of motion
• pain with overhead motions
• loss of rotator cuff muscular strength and endurance
• loss of scapular stabilizers muscle strength and endurance
• inability to lie on the affected shoulder

Dislocation: The shoulder joint is the most frequently dislocated joint of the body. Because it moves in several directions, your shoulder can dislocate forward, backward or downward, completely or partially, though most dislocations occur through the front of the shoulder. In addition, fibrous tissue that joins the bones of your shoulder can be stretched or torn, often complicating the dislocation.

It takes a strong force, such as a sudden blow to your shoulder, to pull the bones out of place. Extreme rotation of your shoulder joint can pop the ball of your upper arm bone out of your shoulder socket.
Shoulder dislocation is a common injury in contact sports, such as football and hockey, and in sports that may involve falls, such as downhill skiing, gymnastics and volleyball.

Dislocated shoulder signs and symptoms may include:

• A visibly deformed or out-of-place shoulder.
• Swelling or bruising.
• Intense pain.
• Inability to move the joint.

Rotator cuff injuries: The rotator cuff tendons cover the head of the humerus (upper arm bone), helping you to raise and rotate your arm. When one or more of the rotator cuff tendons is torn, the tendon becomes partially or completely detached from the head of the humerus. Most tears occur in the supraspinatus tendon, but other parts of the rotator cuff may also be involved. In many cases, torn tendons begin by fraying. As the damage progresses, the tendon can completely tear, sometimes with lifting a heavy object.

There are different types of tears.

Partial tear: This type of tear does not completely detach the tendon from the bone. It is called partial because the tear goes only partially through the thickness of the tendon. The tendon is still attached to the bone, but it is thinned.

Full-thickness tear: With this type of tear, there is detachment of part of the tendon from the bone.

• When only a small part of the tendon is detached from the bone, it is referred to as a full-thickness incomplete tear.
• When a tendon is completely detached from the bone, it is referred to as a full-thickness complete tear. With a full-thickness complete tear, there is basically a hole in the tendon.

The most common symptoms of a rotator cuff tear include:

• Pain at rest and at night, particularly if lying on the affected shoulder
• Pain when lifting and lowering your arm or with specific movements
• Weakness when lifting or rotating your arm
• Crepitus, or a crackling sensation, when moving your shoulder in certain  positions

Rotator cuff tears as a result of overuse are most common in older individuals and athletes competing in overhead sports such as baseball, tennis, basketball, golf, and swimming. Tears resulting from trauma are typically attributed to falls or collision sports such as football, lacrosse, and ice hockey.

Muscle imbalances: The shoulder complex relies on muscles to provide dynamic stability during its large range of mobility. Proper balance of the muscles surrounding the shoulder complex is also necessary for flexibility and strength; a deficit in flexibility or strength in an agonistic muscle must be compensated for by the antagonist muscle, leading to dysfunction. These muscular imbalances lead to changes in arthrokinematics and movement impairments, which may ultimately cause structural damage.

Dr. Janda suggested that subacromial impingement results from a characteristic pattern of muscle imbalance including weakness of the lower and middle trapezius, serratus anterior, infraspinatus, and deltoid, coupled with tightness of the upper trapezius, pectorals and levator scapula.

Subacromial impingement occurs when the structures in the subacromial space (rotator cuff, biceps tendon long head, and subacromial bursa) become compressed and inflamed under the coracoacromial ligament. The supraspinatus tendon in particular is at highest risk for irritation and subsequent injury because it is the most likely to contact the acromion when the humerus is abducted to 90° and internally rotated 45°.

Functional impingement is related to glenohumeral instability and is sometimes described as “functional instability,” occurring mostly in overhead athletes less than 35 years of age. The act of throwing may cause tissues below the coracoacromial arch to be subjected to subtle microtrauma, leading to inflammation and tendonitis. Shoulder impingement is common in swimmers too and also known as swimmer’s shoulder.

Symptoms of shoulder impingement

• Pain in the top and outer side of your shoulder.
• Pain that’s worse when you lift your arm, especially when you lift it above your head.
• Pain or aching at night, which can affect your sleep.
• Weakness in your arm.