The Rotator Cuff - Overview
As defined in the article “Rotator Cuff Injury and Inflammation” the rotator cuff is in the shoulder joint, and comprises four muscles called: Supraspinatus, Infraspinatus, Subscapularis, and Teres minor respectively. They are illustrated in Figure 1 below, reproduced from the same article:
(Reproduced from “Rotator Cuff Injury and Inflammation”)
As described in the referenced article, these muscles function together to help the movement of the shoulder joint and stabilise it.
Causes, Symptoms, and Prevention of Rotator Cuff Injuries
According to Wedro and Stöppler (Ed.) in their article “Rotator Cuff Disorders” (n.d.), the usual cause of a problem in the rotator cuff is that tendons within it can become restricted so that they rub the bones there and become either damaged or inflamed, perhaps also causing bleeding. Those same tendons can consequently acquire scar tissue, which is less strong than the normal tissue. Such injuries to the combination of muscles and tendons in the rotator cuff are often referred to as strains, categorized by the extent of damage caused. For example Grade1 strains are those that may overstretch the tendons but not actually causing a tear, then Grade 2 injury is one that has caused minor tears in muscle or tendon, and Grade 3 damage is a full tear of the affected tissues. The following Figure illustrates those three grades:
Figure 2: Grades of Rotator Cuff Strains
(Reproduced from dralansherman.com)
There are several reasons for these injuries to occur. These may include what is referred to as an “acute” injury (e.g. resulting from falling or other accident), from extended and repeated overuse, like throwing in sport, or heavy lifting, or even from progressive degeneration of the rotator cuff elements due to age. Those injuries are usually referred to as “chronic” injuries. The various causes can be further defined as follows:
- Can be caused by sudden forceful lifting an arm against a resisting object or force, or by trying to cushion the effect of a fall;
- Significant force is needed to cause such an injury for people younger than (say) 30.
- Often occurs with people involved in sport or in jobs that need extended and repeated “overhead” activity, such as tennis players or carpenters and painters in the construction industry;
- Could be the result of an earlier acute injury that has left the patient with some effect such as a bone spur forming that impinges on a muscle or tendon;
Another cause of rotator cuff injury is a condition known as tendonitis, which may be caused by degradation with age (described later in this paper). It usually affects the area of attachment of the tendon and bone. Due to inadequate blood supply, even a mild form of injury there can be slow to heal, possibly causing a more serious, secondary injury in the rotator cuff.
Wedro and Stöppler provide details of the likely symptoms that will indicate the existence of rotator cuff problems, originating from inflammation that occurs within the unit following a strain or muscle or tendon damage. The inflammation causes swelling, which may not be easy to feel because the source is well beneath the skin. However, because of the restricted space within the rotator cuff, that swelling causes pain and limits the movement of the affected shoulder joint. Details of possibly included symptoms are:
- A sudden feeling of tearing, followed by serious pain originating from both front and rear of the shoulder and extending into the arm towards the elbow;
- Sharp pain for a few days, caused by muscle spasms and internal bleeding;
- Inability to lift the affected arm from the side, caused by a major tear, resulting in loss of muscle strength and pain.
- Pain often worse during the nights, preventing normal sleep patterns;
- Weakness and range of shoulder movement slowly decrease as the pain becomes worse;
- Decreased range of arm movement. Some activities still possible, but lifting the arm higher than the shoulder (either to the front or the side) is not possible.
- Commonest in women between the ages of 30 and 50 years;
- Deep aching sensation felt not only in the shoulder but also on the outside of the upper part of the arm;
- May be localized tenderness over the injured area;
- Pain occurs gradually; worsens if the arm is lifted to the side (“abduction”) or turned inwards (“internal rotation”);
- Can progress to cause a chronic tear, due to the possibility of a blocked blood supply which can severely damage tendon fibers, potentially leading to fraying or complete tearing.
Prevention of rotator cuff injuries is not always possible. The acute injuries caused by accidents and falls may be unavoidable. However the likelihood of injuries caused by overuse can be reduced by the process of “warming up.” This applies not only to sporting activities but to potentially injury-causing activity in the home or workplace. Another preventative measure is to do stretching exercises both before and after such activities.
Types of Rotator Cuff Injury / Inflammation
As described in “Rotator Cuff Injury and Inflammation”, problems that could cause injury or inflammation may commonly include tendonitis, impingement syndrome, and a tear.
Rotator Cuff Tendonitis. An article of this title published by the Cleveland Clinic (n.d.), describes the condition as an inflammation of the shoulder muscles, along with an inflammation of the mechanism that provides lubrication, known as the bursa. There is something called “bursitis” which the referenced article describes as actually one of the symptoms of tendonitis. The cause of this condition can be making repeated “overhead” movements such as when throwing, serving in tennis, car washing, window cleaning, etc. Tendonitis is considered to be the mildest type of injury to the rotator cuff.
According to another article with the same title published by aidmyrotatorcuff.com, there are two forms of tendonitis of the rotator cuff – acute and chronic. The acute form usually results from a one-off event such as from a shoulder injury or lifting a heavy object overhead, causing sudden inflammation. In contrast, the chronic form develops over a period, most likely from longer term repetitive activity such as weight training, throwing (like a ball or javelin) or even through painting. It can occur in any one of the rotator cuff tendons but most commonly in the supraspinatus tendon illustrated in Figure 2 below:
(Derived from “Rotator Cuff Tendonitis”: aidmyrotatorcuff.com)
The aidmyrotatorcuff.com article states that the usual symptoms of the tendonitis start with an initially mild shoulder pain that progressively worsens, although in the acute version those symptoms may occur suddenly. Other symptoms may include pain in the upper and front areas of the shoulder, aggravated by “overhead” activities. Although to begin with the pain may be felt only during the activity, it will be eventually be there even when at rest. Sufferers may also experience a restricted range of shoulder movement and tenderness / burning feeling in the shoulder. Other symptoms may include weakness in the shoulder, difficulty or pain when making small movements, difficulty sleeping (particularly lying on that shoulder), and even trouble with simple activities such as hair brushing, dressing, or any activity involving arm movements above shoulder height.
With regard to treating rotator cuff tendonitis, the main recommendations from the aidmyrotatorcuff.com article are rest and avoiding the activities that caused the inflammation, plus to begin early application of cold compression treatment. The sooner it heals, the less likely there is of a later recurrence. Other treatments available include ultrasound therapy and blood flow stimulation therapy (BFST). Those methods are said to heal the tendonitis more effectively and to minimise scar tissue, which can build up on the tendon making it thicker. Also, that scar tissue can bind together the tendons and ligaments in that area, ultimately limiting the range of movement in that shoulder. In extreme cases, the joint could become “frozen”, preventing movement altogether. In less extreme cases, the effect of the scar tissue can leave the tendons weaker and increase the risk of future rotator cuff injury.
For the acute form of tendonitis, medical advice favors the cold compression therapy, started within 48-72 hours of the injury if at all possible. An example of such an appliance is shown in the Figure below:
Figure 4: Shoulder Cold Compression Therapy Appliance
(Reproduced from physiosupplies.com.au)
According to the aidmyrotatorcuff.com article the principle of cold compression therapy is that it interrupts / slows the functions of nerves and cells in the affected area and helps to reduce swelling that could otherwise cause blocking of blood vessels, which could in turn prevent oxygenated blood flowing through the tendons and cause breakdown of tissue cells. Thus without that cold compression therapy the damage to cells is not halted, affecting full healing. The appliance shown in the previous Figure contains a pre-chilled cooling gel pack that not only slows down cell breakdown and damage to tissues, but deadens the pain.
Another form of therapy recommended in the same article uses ultrasound waves that enhance the elasticity of the affected tissues, at the same time as causing increased blood flow to the damaged tendons. It also helps reduce the inflammation and accelerates the healing process. By softening the scar tissue and strengthening the tendons, this therapy minimises the possibility of long-term complications and lowers the risk of future problems.
Once the swelling and inflammation is somewhat lessened, the aidmyrotatorcuff.com article advises using yet another therapy; this one called blood flow stimulation, which applies heat to the tissues by means of safe electromagnetic waves generated in a device worn over the shoulder, as shown in the following Figure:
Figure 5: Blood Flow Stimulation Therapy
(Reproduced from aidmyrotatorcuff.com)
According to the article, it is silent in operation and accelerates healing by relaxing the muscles and increasing the oxygen supply to the damaged cell tissue, without side effects.
Rotator Cuff Impingement Syndrome. An article in American Family Physician by Fongemie, Buss & Rolnick (Feb 1998) provides information about this disorder and about the tearing of the rotator cuff (described later). It lists the causes of impingement as including: “acromioclavicular joint arthritis, calcified coracoacromial ligament, structural abnormalities of the acromion and weakness of the rotator cuff muscles.” The article suggests that symptoms include pain – especially pain at night if the patient lies on that shoulder, as well as a weakness in the joint and lost motion. It also states that a family doctor who is familiar with rotator cuff problems should be able to diagnose this and other rotator cuff disorders. The article describes the key element in diagnosis as testing for pain-free passive arm movement while the doctor is pressing down on the top of the shoulder (thus reducing the subacromial space). If the patient experiences pain during such maneuvers but no pain when the pressure on the shoulder is removed, then impingement is the likely problem.
Diagnosis by radiography is also possible, especially in cases where the impingement is due to an anatomic abnormality, arthritis, or “calcific deposits” (e.g. bone spurs).
The “subacromial space” (see Figure), between the underside of the acromion and the upper part of the humerus, is called the “impingement interval.”When impingement occurs, that space – normally narrow and at its narrowest when the arm is raised – disappears, due typically to the effects of one of the conditions listed above.
Figure 6: Shoulder Impingement Syndrome
(Reproduced from optimumsportsperformance.com)
According to the Fongemie, Buss & Rolnick article, the impingement condition can be classified as being at one of three stages:
- Patients generally less than 25 years old, often caused by overuse and “involves edema and/or hemorrhage.” Usually reversible;
- Patients usually between 25 and 40 when this more advanced condition exists. Effects include fibrosis in addition to “irreversible tendon changes”;
- Patients typically over 50; damage often includes a ruptured or torn tendon. The condition is likely to have been present for a number of years.
Because other conditions can display symptoms very similar to impingement, the article also discusses differential diagnosis (diagnosis arrived at by examining all the possible causes for a set of symptoms). The article includes a Table encompassing a wide range of symptoms involving shoulder pain, and possible findings and treatments, which is reproduced for information at Appendix A to this paper.
Treatment of impingement depends upon the classified stage (1, 2, or 3). For stage 1 patients the usual remedy is rest and not repeating the activity that triggered the problem. In some cases physical therapy may be needed plus the use of “Nonsteroidal anti-inflammatory drugs (NSAIDS)” and treating with application of ice can provide pain relief, e.g. by applying an ice pack for say 20 minutes perhaps three times daily. The following Figure shows an example of an ice pack applied to a shoulder.
Figure 7: Shoulder Ice Pack
(Reproduced from www.ice-packs-store.com)
It is not advisable to support the affected arm in a sling because rendering the joint immobile can cause another problem known as “adhesive capsulitis.” As soon as the pain has abated, it is recommended that the patient embarks on a dedicated program to strengthen the rotator cuff and to reduce the possibility of future injury. The most important movements to exercise for this purpose are “internal rotation, external rotation and abduction.” Note that in addition to torque generation, the rotator cuff stabilizes the “glenohumeral joint” so a benefit of gaining stronger muscles in the rotator cuff is better stabilization of that joint and therefore less likelihood of impingement. To begin with, such an exercise program might be repeated (say) between three and five times weekly, using light weights (say four to eight ounces) to perform somewhere between 10 and 40 repetitions on each occasion.
For patients classified as being stage 2, it is probable that a more formally designed program of physical therapy will be necessary. Isometric stretching is good to help with restoration of the full range of movement, and isotonic exercises (using fixed weights) are preferable. Repetitions using relatively light weights are used, perhaps coupled with sport-specific movements (e.g. for swimming or throwing). It may also be helpful to include other physical therapy modes such as “electrogalvanic stimulation, ultrasound treatment and transverse friction massages.”
In specific cases, there may be a case for using therapeutic injections of lidocaine with a corticosterioid. Reasons for using those injections may include:
- Cases that do not respond to physical therapy and NSAIDS treatment;
- Older patients who exhibit lesions such as subacromial spurs but who are not ideal candidates for surgery (periodic injections can help in those cases);
- For diagnosis. In cases where fails to show improvement after a subacromial space injection, but x-rays are normal and a physical examination shows no specific evidence of a problem, it is possible the cause is other than the rotator cuff. If the pain is lessened during a repeat impingement test after the therapeutic injection will verify that diagnosis.
Although injections into the shoulder can be via a number of points of entry, the posterior subacromial method is preferred, as shown in the following Figure. Also the doctor is better able to avoid hitting the head of the humerus by angling the needle towards the acromion underside. Because the tendon should not be injected directly, the needle must be angled away if any resistance is felt.
Figure 8: Posterior Approach Subacromial Injection
(Reproduced from www.shoulderdoc.co.uk)
Rotator Cuff Tears. According to an article “Rotator Cuff Tears” (reviewed May 2011) on the OrthoInfo website, this common source of shoulder pain affected circa two million people in the U.S. in 2008. It stated that there are two main causes of these tears, through injury (acute tear) or due to degeneration:
- Acute tear: Could be caused by falling onto an outstretched arm or by lifting a heavy object with a jerk;
- Degenerative tear: A gradual wearing of a tendon, which is a natural effect as we age. These tears are more common in what’s called “the dominant arm” and are sometimes referred to as “chronic” tears.
According to the OrthoInfo article, factors contributing to a degenerative or chronic rotator cuff tear can include:
- Stress caused by Repetitive Actions: Sport such as “baseball , tennis rowing,, weightlifting” can cause tears through over-use. The same can apply to non-sporting activity including routine tasks in many different jobs;
- Reduced Blood Supply: Blood supply to the tendons in the rotator cuff lessens with age. That reduces the body’s self-repair capability and can lead to a tear;
- Bone Spurs: In older people, spurs of bone can develop, especially on the underside of the acromion bone, and can cause impingement by rubbing on the rotator cuff tendon, weakening it and making it more prone to tearing.
The same article notes that the risk is greater for people aged over 40 because most tears are the result of normal age-related wear and tear, and that all those who engage in sport or in work that requires activity above head height (e.g. painters or carpenters) are at increased risk of incurring a rotator cuff tear.
The Fongemie, Buss & Rolnick (Feb 1998) article notes that not all diagnosed tears of the rotator cuff require correction by surgery. In fact the article claims that in the case of the majority of older patients recovery can be achieved without surgical intervention. On the other hand for those patients younger than (say) 60 who have a rotator cuff tear that prevents normal function, or for patients who have received the normal conservative type of treatment for perhaps six months without noticeable improvement, surgery might be a valid option. These days, for suitable patient candidates, surgery is usually implemented in an “arthroscopic” process in which a very small camera (arthroscope) is inserted through a small incision, as shown in the following Figure:
Figure 9: Shoulder Arthroscopy
(Reproduced from www.shoulderdoc.co.uk)
An article entitled “Shoulder Arthroscopy” (June 2011) describes the technique used to fix various shoulder problems, including a tear in the rotator cuff. The article states that most people are given a general anaesthetic before surgery, although in some cases local anaesthetic supplemented by a sedative may be used. In either case the patient will feel no pain during the procedure. The surgeon inserts the arthroscope – which is connected to a monitor screen – into the shoulder via a small incision, then uses the camera to inspect all the relevant tissues. If he locates a tear, he will make one or more additional incisions to insert other instruments used to fix the tear. For torn muscles, this will be done by bringing the torn edges of the muscle together. If needed, small rivet-like objects called “suture anchors” will be used to help attach any tendon to bone. Those are made of material than can remain the body following the surgery. When the surgery is completed the surgeon closes up all incisions using stitches, then covers the local area with surgical dressings.
Recovery and Rehabilitation
Cluett (updated Jan 2011) published anAbout.com guide entitled “Rehab After Rotator Cuff Surgery.” It suggested that in most cases the surgical procedures for rotator cuff repairs are performed on an out-patient basis, with usually no need to overnight in the hospital afterwards. Depending on the actual repair work needed, the whole process may take a few hours.
Following the surgery, the arm is placed in an “abduction sling” – one that holds the arm a little away from the side of the torso, so that the affected rotator cuff tendons are positioned in a more relaxed attitude. It is usual to keep the patient at the hospital until the expected post-operative pain is deemed to be satisfactorily under control.
Recovery from surgery similar to that described above may take between one and six months, and may involve wearing a sling for the initial period, plus there will need to be a program of physical therapy to regain full use of the shoulder joint and therefore the full range of movement of the associated arm. It is important to ensure that proper pain control is observed. For example, if prescribed medications for that, take a small dose when pain begins, rather than wait for it to become more extreme. If necessary try different medications and remember that ice pack application may be the most effective way to control pain.
During the first phase of recovery, depending on the seriousness of the injury, shoulder movement should be limited to avoid putting tension on the repaired tissues. This is called “passive motion” and may last up to six weeks. In passive motion, the doctor or therapist will move the injured shoulder and will show the patient how to move the shoulder for themselves, without causing contraction of the muscles within the rotator cuff.
When the tendons have healed sufficiently to allow them to begin (in moderation) to be used to move the arm, the patient will enter phase 2 of the recovery process: “active motion.” The term means that the patient is encouraged to move the arm, but not against resistance, e.g. no lifting. That phase of recovery could take as long as 12 weeks in some cases.
The next stage of recovery (phase 3: strengthening) is probably the most important. It is in this phase that the by now seriously weakened muscles of the rotator cuff need strengthening to work towards normal levels of activity. That process does not require the use of heavy weights. Under the direction of an experienced therapist, a series of exercises, perhaps using either light weights or resistance bands will provide the needed strengthening regime. The examples of rotator cuff strengthening exercises below, derived from PhysioAdvisor.com are provided for information only – it is important to check with the physiotherapist for individual circumstances before performing any specific exercises.
The fourth and final recovery phase is the return to full activity, which may be as long as between four and six months after the surgery. Factors affecting the actual duration of recovery are the size of the original tear, the ability to effect a full repair, and the patient’s own commitment to the rehabilitation program. A crucial factor is knowing exactly when to progress to the next phase of rehabilitation. Because all patients and all injuries are individual, the advice of the therapist is paramount if the recovery process is to be successfully completed in as short as possible a time. Rehabilitation under expert guidance is essential if the patient is to successfully regain full use of the injured shoulder and the rotator cuff within it.
Cluett, Jonathan. “Rehab After Rotator Cuff Surgery.” (Updated Jan 2011). About.com Orthopedics. Web. 7 February 2013.
Fongemie, Allen, E., Buss, Daniel, D., & Rolnick, Sharron, J. “Management of Shoulder Impingement Syndrome and Rotator Cuff Tears.” (Feb 1998). American Family Physician 1998 Feb 15;57(4):667-674. Web. 7 February 2013.
“Grades of Rotator Cuff Strains.” (Illustration). (n.d.). (www.dralansherman.com). Web. 7 February 2013.
“Posterior Approach Subacromial Injection.” (Illustration). (n.d.). (www.shoulderdoc.co.uk). Web. 7 February 2013.
“Rotator Cuff Injury and Inflammation.” (n.d.). Patient.co.uk. Web. 6 February 2013.
“Rotator Cuff Strengthening Exercises.” (2008). PhysioAdvisor.com. Web. 8 February 2013.
“Rotator Cuff Tears.” (reviewed May 2011). OrthoInfo. Web. 7 February 2013.
“Rotator Cuff Tendonitis.” (n.d.). aidmyrotatorcuff.com. Web. 6 February 2013.
“Rotator Cuff Tendonitis.” (n.d.). Cleveland Clinic Health Hub. Web. 6 February 2013.
“Shoulder Arthroscopy.” (Illustration). (n.d.). (www.shoulderdoc.co.uk). Web. 7 Feb 2013.
“Shoulder Arthroscopy.” (June 2011). MedlinePlus, the U.S. National Library of Medicine. Web. 7 February 2013.
“Shoulder Cold Compression Therapy Appliance” (Illustration). (n.d.). (physiosupplies.com.au). Web. 7 February 2013.
“Shoulder Ice Pack.” (Illustration). (n.d.). (www.ice-packs-store.com). Web. 7 Feb 2013.
“Shoulder Impingement Syndrome” (Illustration). (n.d.). (optimumsportsperformance.com). Web. 7 February 2013.
Wedro, Benjamin and Stöppler, Melissa, C. (Ed.). “Rotator Cuff Disorders.” (n.d.). emedicinehealth.com. Web. 8 February 2013.
Appendix A: Causes of Shoulder Pain
Reproduced from: Fongemie, Allen, E., Buss, Daniel, D., & Rolnick, Sharron, J. “Management of Shoulder Impingement Syndrome and Rotator Cuff Tears.” (Feb 1998)
Appendix A (continued)