A Dislocated Shoulder Can Mean Long-Term Problems

If you’ve ever suffered a dislocated shoulder, then you know that this orthopedic mishap is more than painful: It can leave your arm feeling as though it has come unplugged from your body. Shoulder dislocations are a common problem at all ages, but about one in five strike men and women who are 60 or older.

Treating a dislocated shoulder in a younger person usually ends the misery right away, but that’s often not the case for older adults. The problem: Older men and women who get these injuries also have accompanying tissue damage that often goes overlooked or is misdiagnosed, according to a study in the October 2012 issue of the Journal of the American Academy of Orthopaedic Surgeons. As a result, a simple dislocated shoulder can end up causing persistent discomfort and limited range of motion that lasts for years.

Living with shoulder pain and stiffness can slow down an active lifestyle and interfere with daily activities as simple as getting dressed or reaching for a book on a shelf. But knowing how to recognize—and prevent—shoulder problems can help keep these hardworking joints in action.

The shoulder: flexible, but unstable

Your shoulders are among your body’s largest and most versatile joints. Unlike elbows or knees, shoulders bend up and down, forward and backward. The unique design of the shoulder joint creates this extraordinary flexibility, but it can also increase the risk for certain problems, especially later in life.

Like some other joints, such as the hip, the shoulder is formed by a ball-and-socket structure. In the shoulder, the “ball” is the head of the upper arm bone, or humerus, which rests on a socket-like depression, called the glenoid, in the shoulder blade. Because the head is larger than the glenoid, a sheath of muscles and tendons—the rotator cuff—holds it in place, while also helping to control arm movement.

The downside of the shoulder’s tremendous flexibility is that it’s a relatively unstable joint. A dislocated shoulder occurs when the head of the humerus “pops out” of the glenoid, or socket. A dislocation often results from some form of trauma, such as a car accident, though even a minor stumble can trigger one.

Imagine you trip over a footstool but manage to break your fall by holding out your hands. As your outstretched palms strike the ground, the force of landing can pull the upper arm backward, causing it to shift out of position. (A shoulder can dislocate forward, backward or downward.) A dislocated shoulder leaves your arm appearing slightly out of place. Besides pain in the upper arm, you may experience numbness, swelling, a “pins-and-needles” sensation and bruising. Surrounding muscles may go into spasm, adding to the pain.

If you dislocate a shoulder, don’t attempt to pop it back into place yourself or allow a friend to try. Instead, go to an emergency room, since great care must be taken not to fracture the arm bone or rupture an artery. The usual treatment for a dislocated shoulder is a procedure known as a closed reduction, in which a doctor manually reinserts the ball of the humerus into the joint socket. Afterward, you’ll need to apply ice regularly to bring down swelling and you may have to keep your arm in a sling for a few weeks. Your doctor may also refer you to a physical rehabilitation specialist, who can help restore your arm’s range of motion.

The rotator cuff at risk

A patient usually feels immediate relief after having his or her shoulder reassembled. But pain and other symptoms often linger in older men and women because of changes that occur in the aging shoulder. Over time, the muscles and tendons that form the rotator cuff become weak and brittle. These changes make the rotator cuff much more likely to tear if you dislocate a shoulder or have a related injury.

Among people 40 and older, shoulder dislocations cause a torn rotator cuff in anywhere from 35 percent to 86 percent of cases. A 2012 U.K. study published in the Journal of Bone and Joint Surgery found that women 60 and over who dislocate shoulders in falls have the highest risk for tearing a rotator cuff (as well as fracturing a bone, especially in the upper arm). By contrast, younger people who dislocate shoulders are more likely to damage other supporting tissues, such as the labrum, a type of cartilage that helps stabilize the head of the humerus.

In addition to shoulder dislocations, simple stress and overuse is a major cause of rotator cuff tears, too. If you play sports that require a lot of throwing or other overhead arm movements, such as baseball, tennis or swimming, you may be at risk for rotator cuff problems. The same is true if you perform manual labor that involves similar repetitive movement of the shoulders, such as house painting and carpentry.

Bone spurs, or overgrowths, can tear tendons in the rotator cuff as well. What’s more, blood supply to these tissues may diminish with age, which interferes with your body’s ability to repair these tears.

Rotator cuff tears cause pain, especially in the upper and outer shoulder, and particularly when you reach upward or sleep on your injured side. Your shoulder may feel weak and make a clicking or cracking sound when you move it. In older patients, doctors usually recommend treating these symptoms with rest, over-the-counter pain relievers or, if the latter don’t work, cortisone injections. Stretching and strength exercises can restore shoulder movement and strength and help prevent future problems, too.

If you’re still experiencing pain and loss of strength despite these steps, a doctor may recommend surgery to repair a torn rotator cuff, which usually involves reattaching the tendon to the head of the humerus. The procedure can be performed in the traditional “open” manner or with arthroscopy, in which a surgeon uses a tiny scope and instruments to perform surgery.

Nerve injuries and other collateral damage

Doctors sometimes misdiagnose rotator cuff tears as damaged nerves. However, the latter are a concern in older men and women who suffer shoulder dislocations., likely because nerve tissue becomes less resilient with age. One study found that a little over 9 percent of patients 60 and older with a dislocated shoulder displayed weakness and loss of sensation.

In particular, a dislocated shoulder can stretch a network of nerves called the brachial plexus, which conducts signals from the spine to the shoulder, arm and hand. That can lead to temporary shoulder paralysis, which typically fades within a few months. Doctors sometimes call the combination of shoulder dislocation, torn rotator cuff and damaged brachial plexus the “terrible triad of the shoulder.”

Damage to blood vessels is a less common injury that can accompany a dislocated shoulder, but one that’s more likely to occur in older adults: More than 90 percent of artery injuries related to a dislocated shoulder occur in people over 50. That’s probably because arteries become stiff and lose elasticity with age, making them more likely to tear when stretched. Signs that you might have sustained artery damage include pale skin, a burning or tingling sensation, a drop in body temperature, low pulse in the arteries in your wrist, and bruising that appears to be growing worse. See a doctor immediately if you develop any of these symptoms.