The rotator cuff is a group of four muscles that surround the shoulder joint and help to keep it stable. Shoulder tendonitis is a condition caused by inflammation of the rotator cuff and/or biceps tendons. These tendons connect the rotator cuff and bicep muscles to adjacent bones.
Shoulder tendonitis can vary widely from case to case in terms of its severity. In some cases, the inflammation may be mild and may affect only part of the rotator cuff. In other cases, it can be severe enough to affect most of the tendons of the rotator cuff and biceps.
This injury is usually the result of the tendon being pinched by adjacent structures. This condition is often referred to as rotator cuff impingement syndrome. The rotator cuff tendon passes through a narrow space between the acromion process of the scapula and the head of the humerus. Any process which causes further narrowing of this space can precipitate impingement syndrome. It can occur in sports that require the arm to be used in repeated overhead activity or in abducted position e.g. weightlifting, racket sports, baseball or even certain swimming strokes. When the shoulder tendonitis arises from inflammation of a rotator cuff tendon, it is also called rotator cuff tendonitis.
Shoulder weakness, pain and tenderness, as well as an inability to hold the arm in certain positions, are the typical symptoms. A frequent complaint is night pain, often disturbing sleep, particularly when the patient lies on the affected shoulder. There may be a grinding or popping sensation during movement of the shoulder. Onset of symptoms may be acute, following an injury, or insidious, particularly in older patients, where no specific injury occurs.The injury is most commonly treated by resting and icing the shoulder and allowing the injured tendons to recover naturally.
One of the most common causes of shoulder tendonitis is the pinching of a rotator cuff tendon. This can happen, for example, if it gets stuck within the shoulder blade socket. Another name for this type of injury is rotator cuff impingement, which is alluded to above.
Another common cause of this condition is overuse of the shoulder and the four muscles that control its movements. These four muscles and their tendons form a “cuff” known as the rotator cuff. The rotator cuff muscles help to secure the ball of the upper arm bone within the shoulder socket.
Overworking the rotator cuff muscles can result in the tendons that connect them to the bones of the shoulder becoming irritated. Inflammation and swelling of these tendons can then soon develop.
Activities that require movement of the arm above the shoulder can overwork the shoulder muscles if they are repetitive enough. Examples of these activities might be:
Swimming, when strokes like the crawl require movement of the arm overhead;
Painting a ceiling or the upper part of a wall;
Serving a tennis ball;
Throwing or pitching a cricket ball or baseball.
In addition to the above activities, there are a number of factors that can increase the chances of developing shoulder tendonitis:
Having tight or underdeveloped shoulder muscles;
An imbalance of strength among the muscles of the shoulder. In this case, the relatively weak muscles may be over stressed by having to “keep up” with the other stronger muscles;
Anatomical variations, like an irregularity in the shape of the acromion bone. A protrusion may lead to a tendon rubbing against bone over time;
The formation of excess calcium deposits – bony growths called bone spurs or osteophytes – on the bones of the shoulder can lead to friction, causing irritation or a tear of a tendon;
Experiencing a blow to the shoulder; or
Other shoulder trauma (such as trying to break a fall with an outstretched hand).
Swelling and/or redness over the shoulder area if inflammation is present;
Difficulty holding the arm in certain positions, especially in positions at or above shoulder height.
These symptoms can also be experienced with other shoulder problems, like shoulder bursitis for example. Anyone experiencing these symptoms would be wise not to automatically assume they are due to shoulder tendonitis. Instead, the best course of action would be to seek medical advice as soon as possible.
If medical help is not obtained soon enough, the symptoms may gradually worsen to include:
Difficulty sleeping because of the shoulder pain;
Significant loss of arm strength and difficulty carrying objects of even moderate weight;
Difficulty performing everyday tasks. For example, putting on a coat or shirt (due to difficulty moving the injured arm behind the back).
Difficulty placing objects on shelves above shoulder height.
Left untreated, shoulder tendonitis can progress to affect many activities that we take for granted in everyday life.
To understand the cause of the symptoms described above, a doctor will likely review your medical history. He or she will be interested in any instances of previous shoulder injuries and how they may be related to the current problem.
He or she will also likely perform a physical examination of the injured shoulder. The patient may be asked to hold his or her arm in various positions. The goal of the doctor will be to see which arm positions the patient has difficulty holding.
A doctor may also request an imaging study of the injured shoulder using X-ray, MRI or ultrasound technology. Ultrasound and MRI scanning are the two most useful investigations in the diagnosis of rotator cuff problems. However, current evidence suggests that ultrasound is as good as MRI in diagnosing rotator cuff injuries. An MRI study, for example, will provide detailed images of the structures (including soft tissues) in the shoulder joint. The doctor can use these images to assess the type and extent of damage inside the shoulder joint.
The most common treatment strategy recommended by doctors for shoulder tendonitis will include the following:
Resting the shoulder by temporarily refraining from activity that may further aggravate the shoulder or bicep tendonitis. This may include wearing an arm sling. The sling will help to prevent the rotator cuff muscles from having to bear the weight of the arm itself. A shoulder brace can also help take the stress off the rotator cuff muscles and tendons;
To ease the pain and inflammation, doctors may suggest taking a non steroidal anti- inflammatory medication such as Advil or paracetamol with or without codeine;
Corticosteroid and local anaesthetic injections may also be used to control the tendon inflammation if the anti inflammatory medications do not help. The injection should be given into the subacromial space and not into the tendon itself. It can be repeated after a few months, but not more than three injections should be given in a year;
Doctors may also suggest a course of physical therapy exercises to strengthen the rotator cuff and/or bicep muscles. This step should not be underestimated. It will help to reduce the risk of the condition recurring in the future. Evidence suggests that physiotherapy and steroid injections are equally beneficial in the short-term;
Minor rotator cuff tears sometimes respond to physiotherapy and steroid injections, but large symptomatic tears usually need surgical input.