Dr. MJ Bazos MD,
and Answers About Shoulder Problems
This fact sheet first answers general questions
about the shoulder and shoulder problems. It then answers questions about
specific shoulder problems (dislocation, separation, tendinitis, bursitis,
impingement syndrome, torn rotator cuff, frozen shoulder, and fracture) as well
as diseases that can cause shoulder pain (arthritis, myofascial pain, reflex
sympathetic dystrophy, and thoracic outlet syndrome).
How Common Are Shoulder Problems?
According to the American Academy of
Orthopaedic Surgeons, about 4 million people in the U.S. seek medical care each
year for shoulder sprain, strain, dislocation, or other problems. Each year,
shoulder problems account for about 1.5 million visits to orthopaedic
surgeons—doctors who treat disorders of the bones, muscles, and related
What Are the Structures
of the Shoulder and How Does the Shoulder Function?
The shoulder joint is composed of
three bones: the clavicle (collarbone), the scapula (shoulder blade), and the
humerus (upper arm bone) (see diagram). Two joints facilitate shoulder movement.
The acromioclavicular (AC) joint is located between the acromion (part of the
scapula that forms the highest point of the shoulder) and the clavicle. The
glenohumeral joint, commonly called the shoulder joint, is a ball-and-socket
type joint that helps move the shoulder forward and backward and allows the arm
to rotate in a circular fashion or hinge out and up away from the body. (The
ball is the top, rounded portion of the upper arm bone or humerus; the socket,"
or glenoid, is a dish-shaped part of the outer edge of the scapula into which
the ball fits.) The capsule is a soft tissue envelope that encircles the
glenohumeral joint. It is lined by a thin, smooth synovial membrane.
The bones of the shoulder are held in
place by muscles, tendons, and ligaments. Tendons are tough cords of tissue that
attach the shoulder muscles to bone and assist the muscles in moving the
shoulder. Ligaments attach shoulder bones to each other, providing stability.
For example, the front of the joint capsule is anchored by three glenohumeral
Structures of the Shoulder
The rotator cuff is a structure
composed of tendons that, with associated muscles, holds the ball at the top of
the humerus in the glenoid socket and provides mobility and strength to the
shoulder joint. Two filmy sac-like structures called bursae permit smooth
gliding between bone, muscle, and tendon. They cushion and protect the rotator
cuff from the bony arch of the acromion.
What Are the Origin and Causes of
The shoulder is the
most movable joint in the body. However, it is an unstable joint because of the
range of motion allowed. It is easily subject to injury because the ball of the
upper arm is larger than the shoulder socket that holds it. To remain stable,
the shoulder must be anchored by its muscles, tendons, and ligaments. Some
shoulder problems arise from the disruption of these soft tissues as a result of
injury or from overuse or underuse of the shoulder. Other problems arise from a
degenerative process in which tissues break down and no longer function well.
Shoulder pain may be localized or may be
referred to areas around the shoulder or down the arm. Disease within the body
(such as gallbladder, liver, or heart disease, or disease of the cervical spine
of the neck) also may generate pain that travels along nerves to the shoulder.
How Are Shoulder Problems
Following are some of the
ways doctors diagnose shoulder problems:
•Medical history (the patient tells
the doctor about an injury or other condition that might be causing the pain).
•Physical examination to feel for
injury and discover the limits of movement, location of pain, and extent of
•Tests to confirm
the diagnosis of certain conditions. Some of these tests include:
- x ray
- arthrogram—Diagnostic record that can be
seen on an x ray after injection of a contrast fluid into the shoulder joint to
outline structures such as the rotator cuff. In disease or injury, this contrast
fluid may either leak into an area where it does not belong, indicating a tear
or opening, or be blocked from entering an area where there normally is an
- MRI (magnetic resonance imaging)—A
non-invasive procedure in which a machine produces a series of cross-sectional
images of the shoulder. Other diagnostic
tests, such as injection of an anesthetic into and around the shoulder joint,
are discussed in specific sections of this fact sheet.
What Is a Shoulder Dislocation?
The shoulder joint is the most
frequently dislocated major joint of the body. In a typical case of a dislocated
shoulder, a strong force that pulls the shoulder outward (abduction) or extreme
rotation of the joint pops the ball of the humerus out of the shoulder socket.
Dislocation commonly occurs when there is a backward pull on the arm that either
catches the muscles unprepared to resist or overwhelms the muscles. When a
shoulder dislocates frequently, the condition is referred to as shoulder
instability. A partial dislocation where the upper arm bone is partially in and
partially out of the socket is called a subluxation.
What Are the Signs of a Dislocation
and How Is It Diagnosed? The shoulder
can dislocate either forward, backward, or downward. Not only does the arm
appear out of position when the shoulder dislocates, the dislocation also
produces pain. Muscle spasms may increase the intensity of pain. Swelling,
numbness, weakness, and bruising are likely to develop. Problems seen with a
dislocated shoulder are tearing of the ligaments or tendons reinforcing the
joint capsule and, less commonly, nerve damage. Doctors usually diagnose a
dislocation by a physical examination, and x rays may be taken to confirm the
diagnosis and to rule out a related fracture.
How Is a Dislocated Shoulder
Treated? Doctors treat a dislocation
by putting the ball of the humerus back into the joint socket-a procedure called
a reduction. The arm is then immobilized in a sling or a device called a
shoulder immobilizer for several weeks. Usually the doctor recommends resting
the shoulder and applying ice three or four times a day. After pain and swelling
have been controlled, the patient enters a rehabilitation program that includes
exercises to restore the range of motion of the shoulder and strengthen the
muscles to prevent future dislocations. These exercises may progress from simple
motion to the use of weights. After
treatment and recovery, a previously dislocated shoulder may remain more
susceptible to reinjury, especially in young, active individuals. Ligaments may
have been stretched or torn, and the shoulder may tend to dislocate again. A
shoulder that dislocates severely or often, injuring surrounding tissues or
nerves, usually requires surgical repair to tighten stretched ligaments or
reattach torn ones. Sometimes the
doctor performs surgery through a tiny incision into which a small scope
(arthroscope) is inserted to observe the inside of the joint. After this
procedure, called arthroscopic surgery, the shoulder is generally immobilized
for about 6 weeks and full recovery takes several months. Arthroscopic
techniques involving the shoulder are relatively new and many surgeons prefer to
repair a recurrent dislocating shoulder by the time-tested open surgery under
direct vision. There are usually fewer repeat dislocations and improved movement
following open surgery, but it may take a little longer to regain motion.
What Is a Shoulder Separation?
A shoulder separation occurs where the
collarbone (clavicle) meets the shoulder blade (scapula). When ligaments that
hold the joint together are partially or completely torn, the outer end of the
clavicle may slip out of place, preventing it from properly meeting the scapula.
Most often the injury is caused by a blow to the shoulder or by falling on an
outstretched hand. What Are the Signs of a
Shoulder Separation and How Is It Diagnosed?
Both shoulder pain or tenderness and,
occasionally, a bump in the middle of the top of the shoulder (over the AC
joint), are signs that a separation may have occurred. Sometimes the severity of
a separation can be detected by taking x rays while the patient holds a light
weight that pulls on the muscles, making a separation more pronounced.
How Is a Shoulder Separation
Treated? A shoulder separation is
usually treated conservatively by rest and wearing a sling. Soon after injury,
an ice bag may be applied to relieve pain and swelling. After a period of rest,
a therapist helps the patient perform exercises that put the shoulder through
its range of motion. Most shoulder separations heal within 2 or 3 months without
further intervention. However, if ligaments are severely torn, surgical repair
may be required to hold the clavicle in place. A doctor may wait to see if
conservative treatment works before deciding whether surgery is required.
Tendinitis, Bursitis, and
Impingement Syndrome What Are
Tendinitis, Bursitis, and Impingement Syndrome of the Shoulder?
These conditions are closely related
and may occur alone or in combination. If the rotator cuff and bursa are
irritated, inflamed, and swollen, they may become squeezed between the head of
the humerus and the acromion. Repeated motion involving the arms, or the aging
process involving shoulder motion over many years, may also irritate and wear
down the tendons, muscles, and surrounding structures.
Tendinitis is inflammation (redness,
soreness, and swelling) of a tendon. In tendinitis of the shoulder, the rotator
cuff and/or biceps tendon become inflamed, usually as a result of being pinched
by surrounding structures. The injury may vary from mild inflammation to
involvement of most of the rotator cuff. When the rotator cuff tendon becomes
inflamed and thickened, it may get trapped under the acromion. Squeezing of the
rotator cuff is called impingement syndrome.
Tendinitis and impingement syndrome
are often accompanied by inflammation of the bursa sacs that protect the
shoulder. An inflamed bursa is called bursitis. Inflammation caused by a disease
such as rheumatoid arthritis may cause rotator cuff tendinitis and bursitis.
Sports involving overuse of the shoulder and occupations requiring frequent
overhead reaching are other potential causes of irritation to the rotator cuff
or bursa and may lead to inflammation and impingement.
What Are the Signs of Tendinitis
and Bursitis? Signs of these
conditions include the slow onset of discomfort and pain in the upper shoulder
or upper third of the arm and/or difficulty sleeping on the shoulder. Tendinitis
and bursitis also cause pain when the arm is lifted away from the body or
overhead. If tendinitis involves the biceps tendon (the tendon located in front
of the shoulder that helps bend the elbow and turn the forearm), pain will occur
in the front or side of the shoulder and may travel down to the elbow and
forearm. Pain may also occur when the arm is forcefully pushed upward overhead.
How Are These Conditions Diagnosed?
Diagnosis of tendinitis and bursitis
begins with a medical history and physical examination. X rays do not show
tendons or the bursae but may be helpful in ruling out bony abnormalities or
arthritis. The doctor may remove and test fluid from the inflamed area to rule
out infection. Impingement syndrome may be confirmed when injection of a small
amount of anesthetic (lidocaine hydrochloride) into the space under the acromion
relieves pain. How Are Tendinitis,
Bursitis, and Impingement Syndrome Treated?
The first step in treating these
conditions is to reduce pain and inflammation with rest, ice, and
anti-inflammatory medicines such as aspirin, naproxen (Naprosyn*), or ibuprofen
(for example, Advil, Motrin, or Nuprin). In some cases the doctor or therapist
will use ultrasound (gentle sound-wave vibrations) to warm deep tissues and
improve blood flow. Gentle stretching and strengthening exercises are added
gradually. These may be preceded or followed by use of an ice pack. If there is
no improvement, the doctor may inject a corticosteroid medicine into the space
under the acromion. While steroid injections are a common treatment, they must
be used with caution because they may lead to tendon rupture. If there is still
no improvement after 6 to 12 months, the doctor may perform either arthroscopic
or open surgery to repair damage and relieve pressure on the tendons and bursae.
Torn Rotator Cuff
What Is a Torn Rotator Cuff?
One or more rotator cuff tendons may
become inflamed from overuse, aging, a fall on an outstretched hand, or a
collision. Sports requiring repeated overhead arm motion or occupations
requiring heavy lifting also place a strain on rotator cuff tendons and muscles.
Normally tendons are strong, but a longstanding wearing down process may lead to
a tear. What Are the Signs of a
Torn Rotator Cuff? Typically, a person
with a rotator cuff injury feels pain over the deltoid muscle at the top and
outer side of the shoulder, especially when the arm is raised or extended out
from the side of the body. Motions like those involved in getting dressed can be
painful. The shoulder may feel weak, especially when trying to lift the arm into
a horizontal position. A person may also feel or hear a click or pop when the
shoulder is moved. How Is a Torn
Rotator Cuff Diagnosed? Pain or
weakness on outward or inward rotation of the arm may indicate a tear in a
rotator cuff tendon. The patient also feels pain when lowering the arm to the
side after the shoulder is moved backward and the arm is raised. A doctor may
detect weakness but may not be able to determine from a physical examination
where the tear is located. X rays, if taken, may appear normal. An MRI can help
detect a full tendon tear, but does not detect partial tears. If the pain
disappears after the doctor injects a small amount of anesthetic into the area,
impingement is likely to be present. If there is no response to treatment, the
doctor may use an arthrogram, rather than an MRI, to inspect the injured area
and confirm the diagnosis. How is a
Torn Rotator Cuff Treated? Doctors
usually recommend that patients with a rotator cuff injury rest the shoulder,
apply heat or cold to the sore area, and take medicine to relieve pain and
inflammation. Other treatments might be added, such as electrical stimulation of
muscles and nerves, ultrasound, or a cortisone injection near the inflamed area
of the rotator cuff. The patient may need to wear a sling for a few days. If
surgery is not an immediate consideration, exercises are added to the treatment
program to build flexibility and strength and restore the shoulder's function.
If there is no improvement with these conservative treatments and functional
impairment persists, the doctor may perform arthroscopic or open surgical repair
of the torn rotator cuff.
Frozen Shoulder (Adhesive
Capsulitis) What Is a Frozen
Shoulder? As the name implies,
movement of the shoulder is severely restricted in people with a frozen
shoulder. This condition, which doctors call adhesive capsulitis, is frequently
caused by injury that leads to lack of use due to pain. Intermittent periods of
use may cause inflammation. Adhesions (abnormal bands of tissue) grow between
the joint surfaces, restricting motion. There is also a lack of synovial fluid,
which normally lubricates the gap between the arm bone and socket to help the
shoulder joint move. It is this restricted space between the capsule and ball of
the humerus that distinguishes adhesive capsulitis from a less complicated
painful, stiff shoulder. There are a number of risk factors for frozen shoulder,
including diabetes, stroke, accidents, lung disease, and heart disease. The
condition rarely appears in people under 40 years old.
What Are the Signs of a Frozen
Shoulder and How Is It Diagnosed? With
a frozen shoulder, the joint becomes so tight and stiff that it is nearly
impossible to carry out simple movements, such as raising the arm. People
complain that the stiffness and discomfort worsens at night. A doctor may
suspect the patient has a frozen shoulder if a physical examination reveals
limited shoulder movement. An arthrogram may confirm the diagnosis.
How Is a Frozen Shoulder Treated?
Treatment of this disorder focuses on
restoring joint movement and reducing shoulder pain. Usually, treatment begins
with nonsteroidal anti-inflammatory drugs and the application of heat, followed
by gentle stretching exercises. These stretching exercises, which may be
performed in the home with the help of a therapist, are the treatment of choice.
In some cases, transcutaneous electrical nerve stimulation (TENS) with a small
battery-operated unit may be used to reduce pain by blocking nerve impulses. If
these measures are unsuccessful, the doctor may recommend manipulation of the
shoulder under general anesthesia. Surgery to probe into the joint and cut the
adhesions is only necessary in some cases.
What Happens When the Shoulder
Is Fractured? A fracture involves a
partial or total crack through a bone. The break in a bone usually occurs as a
result of an impact injury, such as a fall or blow to the shoulder. A fracture
usually involves the clavicle or the neck (area below the ball) of the humerus.
What Are the Signs of a
Shoulder Fracture and How Is It Diagnosed?
A shoulder fracture that occurs after
a major injury is usually accompanied by severe pain. Within a short time, there
may be redness and bruising around the area. Sometimes a fracture is obvious
because the bones appear out of position. Both diagnosis and severity can be
confirmed by x rays. How Is a
Shoulder Fracture Treated? When a
fracture occurs, the doctor tries to bring the affected parts into a position
that will promote healing and restore arm movement. If the clavicle is
fractured, the patient must at first wear a strap and sling to keep the clavicle
in place. After removing the strap and sling, the doctor will prescribe
exercises to strengthen the shoulder and restore movement. Surgery is
occasionally needed for certain clavicle fractures.
Fracture of the neck of the humerus is
usually treated with a sling or shoulder immobilizer. If the bones are out of
position, surgery may be necessary to reset them. Exercises are also part of
restoring shoulder strength and motion.
Arthritis of the Shoulder
What Is Arthritis of the
Shoulder? Arthritis is a degenerative
disease caused by either wear and tear (osteoarthritis) or an inflammation
(rheumatoid arthritis) of one or more joints. Arthritis not only affects joints;
it may secondarily affect supporting structures such as muscles, tendons, and
ligaments. What Are the Signs of
Shoulder Arthritis and How Is It Diagnosed?
The usual signs of arthritis of the
shoulder are pain, particularly over the AC joint, and a decrease in shoulder
motion. A doctor may suspect the patient has arthritis when there is both pain
and swelling in the joint. The diagnosis may be confirmed by a physical
examination and x rays. Blood tests may be helpful for diagnosing rheumatoid
arthritis, but other tests may be needed as well. Analysis of synovial fluid
from the shoulder joint may be helpful in diagnosing some kinds of arthritis.
Although arthroscopy permits direct visualization of damage to cartilage,
tendons, and ligaments, and may confirm a diagnosis, it is usually only done if
a repair procedure is to be performed.
How Is Arthritis of the Shoulder
Treated? Most often osteoarthritis of
the shoulder is treated with nonsteroidal anti-inflammatory drugs such as
aspirin or ibuprofen. (Rheumatoid arthritis of the shoulder may require physical
therapy and additional medicine, such as corticosteroids.) When conservative
treatment of osteoarthritis of the shoulder fails to relieve pain or improve
function, or when there is severe deterioration of the joint causing parts to
loosen and move out of place, shoulder joint replacement (arthroplasty) may
provide better results. In this operation, a surgeon replaces the shoulder joint
with an artificial ball for the humerus and a cap (glenoid) for the scapula.
Passive shoulder exercises (where someone else moves the arm to rotate the
shoulder joint) are started soon after surgery. Patients begin exercising on
their own about 3 to 6 weeks after surgery. Eventually, stretching and
strengthening exercises become a major part of the rehabilitation program. The
success of the operation often depends on the condition of rotator cuff muscles
prior to surgery and the degree to which the patient follows the exercise
Academy of Orthopaedic Surgeons: http://www.aaos.orgThe
American Physical Therapy Association (APTA): http://www.apta.orgArthritis
College of Rheumatology: http://www.rheumatology.org