Joint Knowledge: Shoulder Impingement

The human shoulder is perhaps one of the most fascinating joints in the body. This joint has a simplistic structure where bones are concerned, a complex setup of soft tissues, and the most range of motion out of all joints. The shoulder can develop a series of problems, however, and shoulder impingement happens to be one of the more common.

A Closer Look at Shoulder Impingement Syndrome

Shoulder impingement syndrome (SIS) is suspected to be the reason behind as much as 44 to 65 percent of complaints regarding shoulder discomfort. SIS can actually be divided into three stages:

• Stage I – Usually diagnosed in patients 25 years old or younger; involves swelling of the rotator cuff and bursa
• Stage II – Usually diagnosed in patients between 25 and 40; may demonstrate irreversible changes to the rotator cuff
• Stage III – Usually diagnosed in patients over 40 years of age; characterized by chronic changes in rotator cuff thickness

What Causes Shoulder Impingement Syndrome?

Shoulder impingement syndrome is caused by the shoulder blade repeatedly rubbing on, pinching, or “impinging” on your rotator cuff. The persistent rubbing causes irritation or swelling of the four muscles that make up the rotator cuff. A rotator cuff is a group of muscles that attach with a “cuff” of tendon tissue at the arm bone. Because the rotator cuff is situated in a relatively tight space between the far point of the shoulder blade (acromion) and the arm bone (humerus), it can be prone to compression.

When the rotator cuff is irritated due to compression or repetitive use, the area can swell. Unfortunately, the placement of the cuff means the enlargement can generate problems with the surrounding structures and tissues of the shoulder. The shoulder is made up of only three bones, but it is also surrounded by ligaments, bursa, and cartilage that keep the shoulder freely moving. To get a closer look at the anatomy of the shoulder, take a look at this overview.

Signs of Shoulder Impingement 

Every individual’s specific symptoms can vary depending on the degree of irritation or damage caused by the rotator cuff rubbing against the acromion. However, some of the general signs and symptoms can include:

• Discomfort when reaching over your head
• Tenderness at the very front of your shoulder
• Discomfort that seems to radiate from the shoulder’s front to the outward side of your arm
• Discomfort when you lie on or put pressure on the shoulder
• Weakness or stiffness in the affected shoulder
• Discomfort in your shoulder when you lie down at night

Who Is Most At Risk of Shoulder Impingement?

In general, people who use their shoulders excessively for certain activities may be more at risk for shoulder impingement. For example, someone involved in sports that require repetitive or overhead arm movements may be more at risk for shoulder impingement. Playing tennis, swimming, and baseball are a few good sport-related examples.

Window washing, painting, and other physically demanding forms of labor that involve reaching over your head frequently can also heighten your risks of shoulder impingement. It is also important to note that shoulder impingement can occur during a fall or accident, such as falling directly on your shoulder.

Final Thoughts On Shoulder Impingement Syndrome 

While shoulder impingement syndrome is extremely common, many people with early issues do not seek immediate medical attention for the problem. Usually, with rest and recuperation time, milder SIS will improve within three to six months. But having issues can also mean you are more likely to experience problems later that may require more direct care and longer recovery periods.

Therefore, if you are experiencing shoulder discomfort and suspect that shoulder impingement may be to blame, seeking medical advice is always recommended.