**1. Introduction**

Rotator cuff consists of four muscles supraspinatus, infraspinatus, teres minor and subscapularis. Subscapularis is largest of the four and is attached to the Lesser Tubercle. It constitutes 50–60% of the rotator cuff. It is one of the main anterior stabilizers of the shoulder.

The subscapularis muscle is the primary internal rotator of the shoulder joint. It also gives strong anterior stability along with capsulolabral tissues to prevent anterior dislocation. Recent studies have shown how the subscapularis works together with the infraspinatus muscle to create smooth balancing force couple and provides concentric compression effect.

Subscapularis tears are not as common as tears of the supraspinatus tendon. Subscapularis tendon tears may be isolated or in conjunction with supraspinatus and infraspinatus tendon tears or biceps tear/ subluxation (**Figure 1**).

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The main causes for subscapularis tear with or without other lesions is Sub coracoid impingement with reduced coracohumeral distance. Due to repeated friction in narrow canal beneath the coracoids process, attritional tear of subscapularis happens. When this distance, which normally ranges from 8.7 to 11 mm, is lower than 5 mm, the risk that the subscapularis tendon

Subscapularis Repair

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http://dx.doi.org/10.5772/intechopen.74734

The coracoid impingement may be primary or acquired. Primary causes of sub coracoid impingement are lateralized coracoid process, calcifications or ossifications of the subscapularis tendon, subscapularis muscle hypertrophy, and ganglion cysts. Secondary causes are usually traumatic or degenerative like displaced humeral or scapular fractures, non-unions,

The subscapularis tendon is torn in 63% of patients in whom the biceps tendon is sub-luxated or dislocated as there is continuity between medial margin of pulley and the subscapularis

The shoulder pain related to a subscapularis tendon tear is more anterior compared to the typical pain observed in patients with rotator cuff tears. There is weakness in internal rotation and abduction like buttoning the shirt, adjusting the tie, tucking the shirt in the back etc. as these functions requires active internal rotation. Since in most of the cases anterior supraspinatus and biceps tendon is also involved, forward flexion, supination and abduction- external

On examination there will be increased passive external rotation, Loss of active internal rota-

Lift-off, belly-press, Napoleon and bear-hug are specific tests to assess the subscapularis

**The lift-off test**: This test has 15–20% sensitivity and almost 100% specificity (Barth et al.) [9]. This test is carried out in sitting or in standing position. The patient's arm is kept in internal rotation with the hand is placed at the back at lumbar spine level. In this position patient tries to move the hand away from back by further extending arm and in internal rotation. Now if this movement is possible, examiner can check by providing resistance. The test is positive when the patient is unable to lift the hand away from back indicative of tear of subscapularis.

**The belly-press test**: It is one of the most commonly performed and accurate clinical test for subscapularis tear with sensitivity of 40% and specificity of 97.3%.It is also called as abdominal compression test, In this test patient attempts to press the hand against the belly with

The degree of weakness and pain are indicative of the degree of the lesion (**Figure 3**).

posterior dislocation of the sternoclavicular joint, spur formation, etc., (**Figure 2**).

is torn is high [7, 8].

tendon.

**3. Symptoms**

rotation can also be painful.

**4. Clinical examination**

tion strength.

tendon.

**Figure 1.** Subscapularis anatomy.
