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natomy of the Shoulder

The shoulder is the most mobile joint in the body.
The shoulder joint is similar to a ball-and-socket joint that is comprised of three main bones:

• The collarbone ( clavicle )
• The shoulder blade ( scapula )
• The upper arm bone ( humerus ), which extends from the shoulder blade to the elbow.

The upper end of the humerus where it rotates is a smooth, rounded head (ball) that fits into the glenoid cavity (socket) of the shoulder blade. Because the ball is larger than the socket, it is more flexible, but has less inherent stability. Muscles, tendons and connective tissue protect the shoulder joint and hold the various parts together. Because the shoulder joint is stabilized by muscles and tendons, rather than by bone, the shoulder has great flexibility.

This gives the shoulder joint a wide range of motion enabling movements such as lifting, pushing and pulling however, this great degree of motion has a trade off; the stability of the shoulder is dependent upon the surrounding soft tissue and can result in a larger number of problems not faced by other joints supported by bony structures. A healthy shoulder can be damaged by disease or injury, resulting in severe pain, pseudoparalysis (false paralysis) and muscle weakness. Pain is one of the key reasons people consider joint replacement surgery. Intense pain can also limit your range of motion and prohibit you from performing your normal day-to-day activities or getting a good night's rest. Your doctor may recommend non-surgical treatments initially; however, if conservative treatment has failed to provide you any relief, surgical options may be considered.

houlder Pain
Is an extremely common complaint, and there are many common causes of this problem. It is important to make an accurate diagnosis of the cause of your symptoms so that appropriate treatment can be directed at the cause. If you have shoulder pain, some common causes include:

• Bursitis
• Rotator Cuff Tendonitis

hat is shoulder bursitis?
Many patients seek medical attention for shoulder pain, and a common diagnosis given is 'shoulder bursitis,' or 'shoulder Tendonitis The doctor will then often state that identifying which of these diagnosis is the true cause of pain is not important because the treatment is the same.
This is true. Shoulder bursitis and rotator cuff Tendonitis are all ways of saying there is inflammation of a particular area within the shoulder joint that is causing a common set of symptoms. The best terminology for these symptoms is 'impingement syndrome.' Impingement syndrome occurs when there is inflammation of the rotator cuff tendons and the bursa that surrounds these tendons.

here is the problem that causes shoulder bursitis?
The shoulder is interesting in that several bones, muscles, and ligaments contribute to this complex joint. Impingement syndrome, or shoulder bursitis, occurs when there is inflammation between the top of the humerus (arm bone) and the acromion (tip of the shoulder). Between these bones lies the tendons of the rotator cuff, and the bursa that protects these tendons.
Normally, these tendons slide effortlessly within this space. In some people this space becomes too narrow for normal motion, and the tendons and bursa become inflamed. Inflammation leads to thickening of the tendons and bursa, and contributes to the loss of space in this location. Eventually, this space becomes too narrow to accommodate the tendons and the bursa, and every time these structures move between the bones they are pinched--this is the impingement.

hat causes this problem?
Impingement syndrome is a descriptive term of pinching of the tendons and bursa of the rotator cuff between bones. In many individuals with this problem, the shape of their bones is such that they have less space than most others. Therefore, small thickenings of the tendons or bursa can cause symptoms.

Often there is an initial injury that sets off the process of inflammation. Thereafter, the problem can be self-exacerbating. Once there is an initial injury, the tendons and bursa become inflamed. This inflammation causes a thickening of these structures. The thickening then takes up more space, and therefore the tendons and bursa become are pinched upon even more. This causes more inflammation, and more thickening of the tendons and bursa, and so on.

hat are the symptoms of shoulder bursitis/impingement syndrome?
Common symptoms include:

• Pain with overhead activities (arm above head height)
• Pain while sleeping at night
• Pain over the outside of the shoulder/upper arm

Impingement syndrome and a rotator cuff tear are different problems, and although they are related, the treatment is different. Impingement syndrome is a problem of inflammation around the rotator cuff tendons. A rotator cuff tear is an actual tear within the tendons. The best signs that differentiate these problems area the strength of the rotator cuff muscles. Your orthopedic doctor will be able to specifically isolate these muscles to better determine if a rotator cuff tear is present. A MRI can also show the tendons of the rotator cuff and help determine if a tear is present.

otator Cuff Tear
Rotator cuff tears occur when the tendons of the rotator cuff separate from the bone. Surgery is sometimes necessary for this condition.

• What is a rotator cuff tear?
  A rotator cuff tear occurs when there is an injury to one of the rotator cuff tendons. Rotator cuff tears occur in many shapes and sizes, but can be thought of as a hole in one of the tendons around the shoulder joint. Like most orthopedic conditions, the most common mechanisms of a rotator cuff tear are separated into 'repetitive use' and 'traumatic injuries.'
• Repetitive Use Injury
  In repetitive use injuries to the rotator cuff, repeated activities cause damage to the rotator cuff tendons. Over time, the tendons wear thin and a rotator cuff tear can develop within the tendons. Patients with repetitive use injuries to the rotator cuff often have complaints of shoulder bursitis prior to developing a rotator cuff tear through the tendons.
• Traumatic Injuries
  Traumatic injuries to the rotator cuff are seen after events such as falling on to an outstretched hand. The traumatic event can cause a rotator cuff tear by injuring the rotator cuff tendons. This mechanism is much less common than repetitive use injuries, but when a rotator cuff tear occurs in a patient younger than 60 years old it is usually a traumatic injury.

rozen Shoulder
Frozen shoulder, or adhesive capsulitis, is a condition that causes restriction of motion in the shoulder joint. The cause of a frozen shoulder is not well understood, but it often occurs for no known reason. Frozen shoulder causes the capsule surrounding the shoulder joint to contract and form scar tissue.