Rotator Cuff Disorders

Overview of rotator cuff disorders

The World Health Organisation (WHO) reveals that nearly 50% of the current global population suffers from musculoskeletal injuries of some form or the other. These injuries are more widespread among professional athletes. The main parts of the musculoskeletal system that suffer the injury in such cases are the muscles, tendons, ligaments and soft tissues. The reports of the Center for Disease Control and Prevention show that nearly 22% of the general population suffer from rotator cuff disorders. Nearly 20% of them have high risks of a re-tear injury. Proper treatment is necessary in such cases in order to reduce the global health burden due to rotator cuff disorders.

What is rotator cuff disorder?

Rotator cuff disorder refers to an injury to any of the four small muscles that comprise the rotator cuff. The main function of the rotator cuff is to support the upper arm bone (humerus) within the scapula (socket of the shoulder blade). The constituent muscles of the rotator cuff are- supraspinatus, infraspinatus, teres minor and subscapularis. The supraspinatus initiates the shoulder motion and maintains the balance of the shoulder throughout the range of motion. The infraspinatus and the teres minor help in the external rotation of the shoulder. The subscapularis facilitates the internal rotation of the shoulder. All these muscles function synchronously to provide stability to the shoulder joints and bones. They also maintain the range of motion of the shoulders. Injury to any of these muscles leads to rotator cuff disorders of various types. Incidences of rotator cuff disorders are more prevalent in old people. But children and teens who actively take part in sports and athletic activities are also the vulnerable groups of this disease.

What are the causes of rotator cuff disorders?

An overuse injury is a primary factor behind rotator cuff disorders. But there are other precipitating factors as well. Following is a list of the common causes of rotator cuff disorders-

• Repetitive stress on the tendons and the rotator cuff muscles due to similar movements of the shoulder
• Overuse injuries of the tendons, ligaments due to occupational stress
• The repetitive overhead motion of the arms during sports such as basketball, badminton, tennis, weightlifting
• Sudden lifting of a heavy load
• Reduced blood supply to the rotator cuff tendons (impedes the proper healing of the wounds and injuries)
• Degeneration of tendons, rotator cuff muscles, and ligaments due to aging
• An occurrence of bony outgrowths that causes friction with the rotator cuff tendon
• Performing exercise without sufficient warm up
• Sports injuries
• Damages resulting from proximal humerus fractures, bicep tendon ruptures or shoulder dislocations
• Constriction of the supraspinatus opening that lies below the coracoacromial arch
• Incorrect sports techniques such as improper angle of serving, an incorrect angle of strike
• Accidental trapping of the tendon between the glenoid fossa and the humerus
• Alterations in structures and properties of the rotator cuff
• Stress on the articular and bursal portions of the tendon
• Trapping of the rotator cuff between the postero-superior labrum and the tip of the humerus
• Defective movements or poor postures
• Poor vascular functions or anatomical defects of the rotator cuff that are present from birth
• Tendon inflammation and tendon fibrosis
• Loss of scapular stability and scapular rotations
• Overuse of broad-spectrum medications that can affect the health of the rotator cuff muscles
• Certain diseases like Arthritis, Diabetes, and Gout
• Loosening of joints and muscles of the shoulder (due to aging or existing medical illnesses)
• Deposition of calcium along the tendons close to the rotator cuff muscles
• Rigorous physical activities

What are the different types of rotator cuff disorders?

Given below is the common classification of rotator cuff disorders-

• Partial rotator cuff tear: The soft tissue suffers considerable damage in this case, but does not become completely non-functional.
• Full-thickness rotator cuff tear: A hole in the tendon usually occurs in this case. The soft tissues are completely split. The tendons dislocate at the point of junction with the humerus.

Based on the intensity of tear, rotator cuff disorders can be categorized into the following types-

• Acute rotator cuff tear: It usually follows some accidental injuries that lead to shoulder dislocation or a broken collarbone.
• Degenerative rotator cuff tear: It occurs due to the degeneration of the tendons. It is typically a feature of old age. It is usually symmetric in nature, that is, if one shoulder develops a tear, the other shoulder also develops a tear, even if there is no occurrence of pain.

What are the symptoms of rotator cuff disorders?

Following are the common warning signs of rotator cuff disorders-

• Pain and inflammation in the shoulders
• Pain during normal shoulder movements such as lifting the arms
• Weakness and heaviness of shoulder and arm muscles
• Generation of crackling or popping noise during shoulder movements (Crepitus)
• Limited movements of the shoulder
• Frozen shoulder syndrome
• Sharp pinching pain that radiates to the arms and neck

What diagnostic tests are necessary?

The following diagnostic tests are critical to determining the root cause of rotator cuff disorders-

• X-rays (to detect the presence of bone spurs)
• Ultrasound scan (to detect soft tissue injuries)
• MRI scan (to determine the age of the injuries)

Treatment

• Conservative therapies– These include proper rest, cold packs (ice application) and physical therapy. In case of minor injuries, conservative treatment methods are sufficient for the injury to heal. However, in case of major injuries involving a muscle or tendon tear, surgeries might be required.
• Physical therapy– It is one of the first lines of treatment suggested by the doctor. The patient is taught exercises based on the location of the rotator cuff injury. This therapy aims at reinstating flexibility and strength to the affected shoulder. Physical therapy is also recommended after the surgeries performed for the rotator cuff injuries.
• Injections- If the conservative therapy fails to relieve the pain and the pain starts interfering with sleep, exercise or daily activities, a steroid injection is given in the shoulder joint. These are transient methods of pain relieving. These injections should be used cautiously as they might cause the weakening of the tendon.

Surgical intervention– There are several methods for operating and surgically treating the rotator cuff injuries. Some of them are as follows:

• Arthroscopic tendon repair– This method employs an arthroscope which has fine surgical tools and a video camera attached to it. The arthroscope helps in reattaching the tendon to the bone with the use of few small incisions.
• Open tendon repair– In some cases, an open surgery is performed. In these types of surgeries, a larger incision is given in order to access the detached tendon. Recovery after these surgeries is more uncomfortable as compared to the arthroscopic surgeries.
• Tendon transfer– These surgeries are performed when the tendon is too damaged to be reattached to the bone. The damaged tendon is replaced by a healthy tendon from a nearby tissue.
• Shoulder replacement- These surgeries are performed in case of massive rotator cuff injuries.

 
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