Rotator cuff tear of the shoulder: causes, symptoms, diagnosis, treatment

ICD-10 code

S46.0. Injury of rotator cuff tendon.

What causes a rotator cuff tear?

Rupture of the tendons that make up the rotator cuff is usually a complication of a shoulder dislocation. Most often, the tendons of all three muscles are damaged simultaneously, but isolated ruptures of the supraspinatus tendons or only the infraspinatus and teres minor muscles are also possible.

Anatomy of the Rotator Cuff

The rotator cuff is the anterolateral part of the shoulder joint capsule, into which the tendons of the supraspinatus, infraspinatus, and teres minor muscles are woven. The latter are attached to the adjacent facets of the greater tubercle of the humerus. Such anatomical proximity of muscle fixation allowed traumatologists to combine them into one group (rotator cuff), although they differ in function: the supraspinatus muscle abducts the shoulder forward and outward, the infraspinatus and teres minor muscles rotate the shoulder outward.

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Symptoms of a Rotator Cuff Tear

It is difficult to detect a rotator cuff tear at an early stage, since the clinical picture is masked by the symptoms of a shoulder dislocation and subsequent immobilization with a plaster cast. Patients usually seek help after prolonged rehabilitation treatment that has not been successful.

Patients complain of dysfunction of the shoulder joint, pain, fatigue and a feeling of discomfort in it.

Diagnosis of a rotator cuff tear

Anamnesis

History: shoulder dislocation followed by long-term unsuccessful treatment.

Inspection and physical examination

Palpation reveals pain in the area of the greater tubercle. Movement disorders are especially characteristic - the shoulder cannot be abducted. When attempting to perform this movement, the arm is actively abducted from the body by 20-30°, and then pulled up together with the shoulder girdle (Leclercq's symptom). The range of passive movements is full, but if the shoulder is abducted and not held, the arm falls (symptom of a falling arm). In addition, with passive abduction of the shoulder, a symptom of painful obstruction of the shoulder passing the horizontal level appears, arising due to a decrease in the subacromial space.

It should be noted that when the body is tilted forward, the patient actively abducts the shoulder forward and outward to 90° or more. Normally, when the human body is in a vertical position, the shoulder is abducted as follows: by contracting, the supraspinatus muscle presses the head of the humerus to the glenoid cavity, creating support, and then the deltoid muscle acts on the long lever of the humerus. When the infraspinatus tendon ruptures, the shoulder joint does not close, contraction of the deltoid muscle leads to displacement of the head of the humerus upward, i.e. to a subluxation position, since the axes of the humerus and the glenoid cavity do not coincide. When the body is tilted, these axes are aligned, contraction of the deltoid muscle can close the shoulder joint and hold the limb in a horizontal position.

In the later stages of injury, a “frozen shoulder” symptom may appear, when even passive abduction becomes impossible due to obliteration of the Riedel pouch.

A.F. Krasnov and V.F. Miroshnichenko (1990) identified and pathogenetically substantiated a new symptom characteristic of a rotator cuff tear - the "falling flag of a chess clock" symptom. It is tested as follows: the patient is asked to actively or passively (supporting the elbow with the healthy hand) move the arm forward to a horizontal level, occupying an intermediate position between supination and pronation. Then his arm is bent at the elbow to an angle of 90°. In this position, the forearm is not supported and falls to the medial side (like the flag of a chess clock in time trouble), rotating the shoulder inward. The reason is the lack of antagonists to the internal rotators and the inability to hold the shoulder, weighted by the bent forearm, in a position intermediate between supination and pronation.

Laboratory and instrumental studies

In contrast arthrography of the shoulder joint, a cuff rupture is characterized by filling of the subacromial bursa, which normally does not communicate with the joint, with contrast medium, and a decrease or disappearance of the subacromial space.

Differential diagnosis of rotator cuff tear

A rotator cuff tear should be differentiated from axillary nerve injury, which is indicated by atony and atrophy of the deltoid muscle and loss of cutaneous sensitivity over the outer surface of the upper third of the arm.

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Treatment for a rotator cuff tear

Surgical treatment of rotator cuff tear

The only treatment for this pathology is surgery. The most commonly used method is the "saber" incision proposed by Codman, which runs from the middle of the scapular spine and parallel to it through the acromion downwards by 5-6 cm. The trapezius muscle and acromion are crossed, the deltoid muscle is dissected, the fibrous plate covering the supraspinatus muscle and the subacromial bursa are dissected, reaching the rotator cuff of the shoulder. In recent cases, the shoulder is abducted and the ends of the tendons that have come together are sutured with strong suture material. The wound is sutured layer by layer, including the acromion, which is fastened with two silk sutures. The limb is fixed with a plaster thoracobrachial bandage for 4-6 weeks in a functionally advantageous position.

It should be noted that surgical interventions for rotator cuff tears are variable and depend on the type of injury, its duration, and secondary changes in the injury area.

In the early stages of injury, especially when tendons are torn from the tubercles, the intervention can be performed from the anterolateral approach without dissection or resection of the acromion. In the later stages, when tendons degenerate, shorten and fuse with rough scars to the surrounding tissues, it is not possible to suture them. They resort to plastic surgery Debeyre (movement of the attachment of the supraspinatus muscle) and Pat-Goutalier (simultaneous movement of the supraspinatus, infraspinatus and teres minor muscles), which allow the elimination of the rotator cuff defect.

Approximate period of incapacity

Working capacity is usually restored 3-4 months after surgery.