Injured Rotator Cuff of the Shoulder

The shoulder joint (and its connective muscles, tendons, and ligaments) has a greater range of motion than all other joints. It can allow your arm to move outward to the side, forward and back, do circles in a windmill fashion, and rotate your arm from palm up to palm down. No other joint allows all these movements.

However, the complex anatomical structure that allows such flexibility of movement also makes the shoulder joint somewhat susceptible to injury. The cluster of muscles and connections that facilitates this movement is called the rotator cuff. 

    The muscles of the rotator cuff are:

• Teres minor 
  
• Subscapularis

• Infraspinatus  

•    Supraspinatus (SITS) muscles, helps stabilize the humeral head in the glenoid fossa of the scapula during overhead arm motions (eg, pitching, swimming, weightlifting, serving in racket sports)

 These muscles control the shoulder girdle and its movement. Injury can occur when muscles are strained, torn, or inflammation occurs in the joint as a result of damage.

Description:

When one or more of the rotator cuff tendons is torn, the tendon no longer fully attaches to the head of the humerus. Most tears occur in the supraspinatus muscle and tendon, but other parts of the rotator cuff may also be involved.

There are different types of tears.

• Partial Tear. This type of tear damages the soft tissue, but does not completely sever it.
   
• Full-Thickness Tear. This type of tear is also called a complete tear. It splits the soft tissue into two pieces. In many cases, tendons tear off where they attach to the head of the humerus. With a full-thickness tear, there is basically a hole in the tendon
  
  
  
  
  

           A rotator cuff tear most often occurs within the tendon.

Cause:

There are two main causes of rotator cuff tears: injury and degeneration.

Acute Tear:

If you fall down on your outstretched arm or lift something too heavy with a jerking motion, you can tear your rotator cuff. This type of tear can occur with other shoulder injuries, such as a broken collarbone or dislocated shoulder.

Degenerative Tear:

Most tears are the result of a wearing down of the tendon that occurs slowly over time. This degeneration naturally occurs as we age. Rotator cuff tears are more common in the dominant arm. If you have a degenerative tear in one shoulder, there is a greater risk for a rotator cuff tear in the opposite shoulder -- even if you have no pain in that shoulder.

Several factors contribute to degenerative, or chronic, rotator cuff tears.

• Repetitive stress. Repeating the same shoulder motions again and again can stress your rotator cuff muscles and tendons. Baseball, tennis, rowing, and weightlifting are examples of sports activities that can put you at risk for overuse tears. Many jobs and routine chores can cause overuse tears, as well.

• Lack of blood supply. As we get older, the blood supply in our rotator cuff tendons lessens. Without a good blood supply, the body's natural ability to repair tendon damage is impaired. This can ultimately lead to a tendon tear.

• Bone spurs. As we age, bone spurs (bone overgrowth) often develop on the underside of the acromion bone. When we lift our arms, the spurs rub on the rotator cuff tendon. This condition is called shoulder impingement, and over time will weaken the tendon and make it more likely to tear.

      

 Tendinitis  typically results from chronic impingement of the supraspinatus tendon between the humeral head and coracoacromial arch (the acromion, acromioclavicular joint, coracoid process, and coracoacromial ligament). Activities that require the arm to be moved over the head repeatedly, such as pitching in baseball, lifting heavy weights over the shoulder, serving the ball in racket sports, and swimming freestyle, butterfly, or backstroke, increase the risk. 

·                                         The resultant inflammatory reaction and edema further narrow the subacromial space, accelerating tendon irritation or damage. If the process is not interrupted, the resulting inflammation can lead to partial or complete tear of the rotator cuff. Degenerative rotator cuff tendinitis is common among older (> 40 yr) people who are not athletes for the same reason.

·        

        subacromial bursitis  (inflammation, swelling, and fibrosis of the bursal area above the rotator cuff) commonly results from tendinitis of the cuff.

Risk Factors

Because most rotator cuff tears are largely caused by the normal wear and tear that goes along with aging, people over 40 are at greater risk.

People who do repetitive lifting or overhead activities are also at risk for rotator cuff tears. Athletes are especially vulnerable to overuse tears, particularly tennis players and baseball pitchers. Painters, carpenters, and others who do overhead work also have a greater chance for tears.

Although overuse tears caused by sports activity or overhead work also occur in younger people, most tears in young adults are caused by a traumatic injury, like a fall.

Symptoms and signs:

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 crackling sensation when moving your shoulder in certain positions

Tears that happen suddenly, such as from a fall, usually cause intense pain. There may be a snapping sensation and immediate weakness in your upper arm.

A rotator cuff injury can make it painful to lift your arm out to the side.

Tears that develop slowly due to overuse also cause pain and arm weakness. You may have pain in the shoulder when you lift your arm to the side, or pain that moves down your arm.

 At first, the pain may be mild and only present when lifting your arm over your head, such as reaching into a cupboard. Over-the-counter medication, such as aspirin or ibuprofen, may relieve the pain at first.

Over time, the pain may become more noticeable at rest, and no longer goes away with medications. You may have pain when you lie on the painful side at night.

 The pain and weakness in the shoulder may make routine activities such as combing your hair or reaching behind your back more difficult

Subacromial bursitis, rotator cuff tendinitis, and partial rotator cuff tears cause shoulder pain, especially when the arm is moved overhead. 

The pain usually is worse between 60° and 120° (painful arc of motion) of shoulder abduction or flexion and is usually minimal or absent at < 60° or > 120°. The pain may be described as a dull ache that is poorly localized. Complete rotator cuff tears result in acute pain and weakness of the shoulder. In larger tears of the rotator cuff, weakness of external rotation is particularly apparent.

Suspected rotator cuff injury can be further evaluated with MRI, arthroscopy, or both Medical History and Physical Examination

Diagnosis is by history and physical examination, including provocative maneuvers. The rotator cuff cannot be palpated directly, but it can be assessed indirectly by provocative maneuvers that test its individual components; significant pain or weakness is considered a positive result

Other areas that may be the source of shoulder pain include the acromioclavicular and sternoclavicular joints, cervical spine, biceps tendon, and scapula. These areas should be assessed for any tenderness or deformity indicating a problem in those areas.

The neck is examined as part of any shoulder evaluation because pain can be referred to the shoulder from the cervical spine (particularly with C5 radiculopathy).

 Imaging Tests

Other tests which may help your doctor confirm your diagnosis include:

• X-rays. The first imaging tests performed are usually x-rays. Because x-rays do not show the soft tissues of your shoulder like the rotator cuff, plain x-rays of a shoulder with rotator cuff pain are usually normal or may show a small bone spur.

• Magnetic resonance imaging (MRI) or ultrasound. These studies can better show soft tissues like the rotator cuff tendons. They can show the rotator cuff tear, as well as where the tear is located within the tendon and the size of the tear. An MRI can also give your doctor a better idea of how "old" or "new" a tear is because it can show the quality of the rotator cuff muscles.

please refer  my next blog:

Prevention and Treatment of the rotator cuff Injuries to the Shoulder.........