What Is a Rotator Cuff Injury?
The rotator cuff is made up of four muscles that help move and stabilize the shoulder joint. Damage to any or all of the four muscles and the ligaments that attach these muscles to bone can occur because of acute injury, chronic overuse, or gradual aging. This damage can cause significant pain and disability with decreased range of motion and use of the shoulder joint.
The shoulder is a ball-socket joint that allows the arm to move in many directions. It is made up of the humeral head (the upper end of the bone of the upper arm) fitting into the glenoid fossa of the scapula (shoulder blade). The humeral head is kept in place by the joint capsule and labrum, thick bands of cartilage that form an elongated cone where the humeral head fits. The rotator cuff muscles are the dynamic stabilizers and movers of the shoulder joint and adjust the position of the humeral head and scapula during shoulder movement.
The rotator cuff muscles are anatomically associated with the scapula. Any changes in the movement of the scapula with shoulder range of motion can cause impingement of the rotator cuff muscles, causing problems with the movement of the shoulder itself.
The four rotator cuff muscles include the
- subscapularis, and
- teres minor.
Other muscles that help move and stabilize the shoulder include the deltoid, teres major, corachobrachialis, latissimus dorsi, and pectoralis major.
When the rotator cuff is damaged, a variety of issues arise:
- Pain and spasm limit the range of motion of the shoulder.
- The muscles do not make the small adjustments within the joint to allow the humeral head to move smoothly.
- Fluid accumulation within the joint due to inflammation limits movement.
- There can be impingement on the rotator cuff muscles or the tendons that attach them to the bones. The tendons run through narrow bony spaces, and if there is a change in how the humerus and scapula move, these spaces can become even narrower.
- Arthritis and calcium deposits that form over time limit range of motion. These calcifications may occur along the bony edges of the joint or within the tendons of the rotator cuff muscles.
The severity of injury may range from a mild strain and inflammation of the muscle or tendon, that will lead to no permanent damage, to a partial or complete tear of one of the rotator cuff muscles that might require surgery for rotator cuff repair.
Rotator Cuff Injury Picture
Shoulder. Hooked anterior acromion.
What Are Causes and Risk Factors of Rotator Cuff Injuries?
Injuries to muscle-tendon units are called strains and are classified by the amount of damage to the muscle or tendon fibers. Grade I strains involve stretching of the fibers without any tears. Grade II injuries involve partial muscle or tendon tearing, and grade III injuries are defined as a complete tear of a muscle or tendon.
The muscles and tendons in the rotator cuff group may be damaged in a variety of ways. Damage can occur from an acute injury (for example from a fall or accident), from chronic overuse (like throwing a ball or lifting), or from gradual degeneration of the muscle and tendon that can occur with aging.
- Acute rotator cuff tear
- This injury can develop from sudden powerful raising of the arm against resistance or in an attempt to cushion a fall (for example, heavy lifting or a fall on the shoulder).
- A rotator cuff tear requires a significant amount of force if the person is younger than 30 years of age.
- Chronic tear
- Chronic rotator cuff tears are typically found among people in occupations or sports requiring excessive overhead activity (examples, painters, baseball pitchers, tennis players)
- The chronic injuries may be a result of a previous acute injury that has caused a structural problem within the shoulder and affected the rotator cuff anatomy or function (for example, bone spurs that impinge upon a muscle or tendon, causing inflammation).
- Repetitive trauma to the muscle by everyday movement of the shoulder
- A chronic tear may lead to degenerative changes to the tendon, leading to worsening pain, decreased range of motion, and decreased function.
- Degeneration (wearing out) of the muscles and tendons with age
- This usually occurs where the tendon attaches to bone. The area has poor blood supply and a mild injury may take a long time to heal and potentially lead to a secondary tear of the cuff.
- Calcific tendinitis describes a condition characterized by calcium deposits that develop within the tendon itself where it has sustained chronic inflammation.
- Glenohumeral subluxation
- If the shoulder joint is unstable and loose, the rotator cuff needs to work harder to make certain the joint does not partially dislocate (subluxate) with movements.
- Repetitive stress of these muscles can lead to rotator cuff muscle weakness, discomfort, and chronic injury.
Causes of Rotator Cuff Injuries
Most of the time, rotator cuff injuries are caused by repetitive stress on the rotator cuff, or degeneration caused by aging. Such repetitive stress can include injuries sustained from sports, particularly those that require a lot of shoulder movement such as baseball, tennis, swimming, weightlifting, and football.
As we age, reduced blood supply to the rotator cuff tendons means damage does not repair itself as well, and bone spurs (bony overgrowths) can also weaken the tendon and lead to tears.
What Are Rotator Cuff Injury Symptoms and Signs?
Symptoms of a rotator cuff injury are due to the inflammation that accompanies the strain. This inflammation causes swelling, leading to the clinical picture of pain and decreased range of motion. Because the muscles and tendons of the rotator cuff are hidden well below skin level, it may be hard to feel the swelling that accompanies the injury, but that swelling within the small space that makes up the shoulder joint prevents the normal range of motion of the shoulder and causes the pain that occurs with movement.
- Acute rotator cuff tear
- Symptoms can be a sudden tearing sensation followed by severe pain shooting from the upper shoulder area (both in front and in back) down the arm toward the elbow. There is decreased range of motion of the shoulder because of pain and muscle spasm.
- Acute pain from bleeding and muscle spasm: This may resolve in a few days.
- Large tears may cause the inability abduct the arm (raise it away from the side of the body) due to significant pain and loss of muscle power.
- Chronic rotator cuff tear
- Pain usually is worse at night and may interfere with sleep.
- Gradual weakness and decreased shoulder motion develop as the pain worsens.
- Decrease in the ability to abduct the arm (move it out to the side). This allows the arm to be used for most activities but the affected person is unable to use the injured arm for activities that entail lifting the arm as high as or higher than the shoulder level to the front or side.
- Rotator cuff tendinitis
- More common in women 35-50 years of age
- Deep ache in the shoulder also felt on the outside upper arm over the deltoid muscle
- Point tenderness may be appreciated over the area that is injured
- Pain comes on gradually and becomes worse with lifting the arm to the side (abduction) or turning it inward (internal rotation)
- May lead to a chronic tear: When a rotator cuff tendon becomes inflamed (tend=tendon +itis=inflammation), it runs the risk of losing its blood supply, causing some tendon fibers to die. This increases the risk that the rotator cuff tendon can fray and partially or completely tear.
When Should Someone Seek Medical Care for a Rotator Cuff Injury?
When to Call the Doctor
Not all shoulder pain arises from the shoulder. Sometimes angina, or pain from coronary artery disease from the heart, can be referred to the shoulder. Pain from the gallbladder or diaphragm can also be felt in the shoulder region, often in the shoulder blade area. Pain from a rotator cuff injury is worsened with shoulder movement. If the unexplained shoulder pain is not affected by movement, it is reasonable to seek immediate medical care. If there is concern that the pain is coming from the heart, emergency medical services should be activated (call 911 if available).
- If the shoulder pain persists in spite of home care with rest, ice, and if tolerated, anti-inflammatory medications like ibuprofen (Advil) or naproxen (Naprosyn)
- If shoulder problems (pain) prevent the person from performing routine daily activities or work
- If pain prevents overhead reaching (for example, reaching to get an item in a cabinet above shoulder level)
- If the pain prevents playing sports in which an overhead motion is required (for example, throwing, swinging a racquet, or swimming)
When to Go to the Hospital
It is reasonable to seek emergency medical care if there is worry about a broken bone, if there is numbness or change in sensation in the arm or hand, or if movement in the shoulder becomes acutely limited.
What Tests Do Doctors Use to Diagnose Rotator Cuff Injuries?
The care provider may want to take a thorough history of the acute injury as well as any previous symptoms that may suggest a more long-term problem.
The physical examination often involves observation to look for deformities, muscle wasting, and changes in the appearance of the damaged shoulder compared to the normal one.
Palpation means touching, including feeling the bones that make up the shoulder joint, as well as the shoulder joint itself. These bones include the clavicle (collarbone), scapula (shoulder blade), and humerus (upper arm bone). The muscles of the shoulder may be palpated, trying to find areas of tenderness or pain.
- Evaluation may include the assessment of range of motion of both shoulders. This may be done both passively (as one sits down or lies on one's back and the examiner gently moves the arm in all directions) and actively (the patient moves the arm as far as possible in all directions). This part of the examination may be delayed or not done if a broken bone is suspected. The power of the shoulder muscles can also be assessed this way, depending upon whether the patient can move the shoulder against resistance or perhaps just lift the arm up against gravity.
- Sensation and blood flow in the arm and hand may be assessed, feeling for pulses and determining if there is normal light touch, pain, and vibration sensation in the extremity.
- The neck may also be examined, depending on the age of the person, cause of injury, and symptoms to make certain that the pain in the shoulder is not referred pain from conditions of the cervical spine.
- The health care provider may ask about chest pains or trouble breathing to make certain that the shoulder pain is not referred from the heart.
- A variety of tests may be performed to try to decide which of the four muscles of the rotator cuff is injured or damaged. Each uses muscle contractions to try to find the weak or painful muscle. Examples include the Jobe test for the supraspinatus tendon, the Patte test for the infraspinatus and teres minor muscles, and the Gerber test for the subscapularis muscle.
Plain X-rays are usually taken as a screening exam to look for broken bones or arthritis and bone spurs within or adjacent to the shoulder joint. Sometimes, calcification can be seen along the tendon. Often, the plain X-ray findings are normal in rotator cuff injury.
Advanced Imaging Studies
- Magnetic resonance imaging (MRI): The MRI has become the test of choice for most significant shoulder injuries. This test is able to identify all the structures that make up the rotator cuff and can identify degeneration changes, partial or complete tears of the tendons and muscles, or a combination of all these conditions. Dye may be injected into the shoulder by a radiologist to help better visualize the tissues in the image.
- Ultrasonography: This is a sound wave test that can help evaluate damaged tendons and muscles but has difficulty in assessing the bones of the shoulder. The benefit of ultrasound is that it can be done as the shoulder is moved and can find places where the rotator cuff is being pinched or impinged upon. However, the quality of ultrasound depends upon the skill and experience of the ultrasound technician and radiologist performing the test.
What Are Home Remedies for Rotator Cuff Injuries?
- Rest and ice are the first-line home treatment of any sprain or strain.
- Apply ice for 15-20-minute periods at least three times a day.
- A sling may be helpful to rest the shoulder in an acute injury, but care must be taken not to wear the sling for too long, otherwise the shoulder joint will become stiff and may require significant time and effort in regaining any lost range of motion.
- Anti-inflammatory medications such as ibuprofen or naproxen may help decrease the pain and swelling of the injury. These over-the-counter medications should be taken with care if there are underlying stomach or kidney problems or if the patient is taking a blood thinner like warfarin (Coumadin), heparin (Lovenox), dabigatran (Pradaxa), apixaban (Eliquis), or rivaroxaban (Xarelto). It is always appropriate to check with a health care provider or pharmacist to determine the safety of over-the-counter medications.
What Is the Treatment for a Rotator Cuff Injury?
Initial treatment of a rotator cuff injury begins with rest, ice, and physical therapy to strengthen the muscles of the rotator cuff and to reestablish full range of motion of the shoulder. It may take weeks or longer to reach satisfactory healing.
There are other nonsurgical options available for treatment of rotator cuff injuries, including steroid injections to decrease inflammation in the tight spaces where the muscle tendons run across the shoulder joint, therapeutic ultrasound, shockwave therapy, and dry needling.
If early conservative treatments don't work or if there is a complete tear of the rotator cuff, surgery may be the next alternative to repair those tears that have been identified. As well, other problems may be addressed at time of surgery including debridement (cleaning up) of bone spurs, relieving any areas of muscle or tendon impingement, tightening the joint capsule, or repairing a labrum tear.
An orthopedic surgeon may use an arthroscope (an instrument that is inserted through a small incision) to repair the damage. Depending upon the procedure to be done, an open surgical procedure may be contemplated, where an incision is made into the joint area to allow the repairs to occur.
Early surgery may be offered to athletes who may want an earlier potential return to play.
Chronic Rotator Cuff Tear
- Pain control usually is the goal of treatment. This can be accomplished with rest and acetaminophen (Tylenol), ibuprofen (Advil, Motrin), or naproxen (Aleve).
- Physical therapy and range-of-motion exercises may be helpful with a goal of maintaining shoulder function and strength.
- Steroid injections (betamethasone, methylprednisolone) into the shoulder joint may be helpful to decrease inflammation within the area.
- Patients who continue to have pain and loss of shoulder function may benefit from a referral to an orthopedic surgeon to discuss surgical rotator cuff repair.
- Apply ice to decrease swelling.
- Anti-inflammatory medications like ibuprofen and naproxen may help reduce pain and swelling.
- A sling may help support the arm rest the rotator cuff muscles. Long-term use of a sling is not advised, since it may cause significant stiffening of the shoulder joint, or a frozen shoulder, with complete loss of motion.
- Usually, acute rotator cuff injuries require more than one visit to the health-care provider and may also require referral to an orthopedic specialist for advice and care. Surgery may be considered within a few weeks, especially in younger, active patients, to return the shoulder to full function.
- Indications for surgical treatment include the following:
- Usually for patients younger than 60 years of age
- Complete rotator cuff tears
- Failure of conservative therapy (physical therapy, rest, and anti-inflammatory medications) after six to eight weeks
- Employment or sporting activity that requires constant shoulder use
- The type of surgery depends on the extent of damage to the rotator cuff and the appearance of the shoulder joint. If the tendon damage is extensive and cannot be repaired, other options and alternatives, including tendon transfer surgery, might be explored.
- Beginning care
- Rest the shoulder in a sling for a short period of time. Prolonged use of the sling can cause stiffness, weakness, and loss of motion of the shoulder joint.
- Take anti-inflammatory medicines such as ibuprofen or naproxen.
- More severe cases
- Use the techniques described for beginning care.
- Corticosteroid injections into the shoulder joint may be considered.
- After a few days, ice may be alternated with heat and massage therapy and range-of-motion exercises initiated.
- Perform Codman exercises. These are passive range-of-motion exercises (often initially done with a physical therapist). These exercises are done to increase slowly the amount of motion of the shoulder while putting a low amount of stress on the rotator cuff itself. The exercises are performed as the person leans toward the injured side with the arm hanging freely and slowly moving the arm in a circle. Initially, the circles are small. With improvement and decrease in pain, the circles enlarge (also called pendulum exercises).
- Holding a broom with both hands and moving it in a large arc while relaxing the affected shoulder can passively stretch the soft tissues.
What Follow-up Is Needed for a Rotator Cuff Injury?
- An orthopedic surgeon may be consulted regarding the possible need for surgical repair.
- Primary-care providers and sports-medicine specialists who are not surgeons often also care for patients with rotator cuff injuries.
Physical therapy is an important component of treatment regardless of whether surgery was performed. A health-care provider referral may be needed.
What Are Tips for Preventing Rotator Cuff Injuries?
- Accidents happen and falls may be difficult to prevent, especially in sports.
- Overuse injuries may be prevented by appropriately warming up before performing tasks that will stress the shoulder joint. This applies to daily and work activities as well as sports. Stretching before or after an activity is also a reasonable prevention strategy.
- In sports or on the job, proper technique for the activity being performed may help minimize the risk of injury.
What Is the Prognosis and Healing Time for a Rotator Cuff Injury?
- Depending on the age of the person and the extent of the injury, nonsurgical treatment is reported to have a success rate of 40%-90%.
- Older people may have a much longer healing time to complete recovery.
- Those patients undergoing surgical repair have a high rate of recovery. One study found 94% of the people were satisfied after surgery with lasting relief of pain and improved function. Results depend upon the extent of the injury. Patients with large rotator cuff tears fare less well.
Reviewed on 8/31/2017
Hutson, M., and A. Ward. Oxford Textbook of Musculoskeletal Medicine, 2nd Edition. Oxford University Press, 2016.
Stoller, D.W. Stoller's Orthopaedics and Sports Medicine: The Shoulder, 1st ed. Lippincott Williams & Wilkins, 2014.