The rotator cuff is a group of muscles and tendons that surround and protect the shoulder joint. The shoulder joint, specifically the humerus, clavicle and scapula, allows the ball-in-socket joint to perform a wide range of motions (including adduction, abduction, flexion, extension, internal rotation, external rotation, and 360 degree circumduction). The rotator cuff consists of the supraspinatus, subscapularis, infraspinatus, teres minor, and the tendons associated with each. These muscles and tendons help to stabilize the head of the humerus in the glenoid cavity of the scapula.
When talking about injuries to muscles and tendons, it is important to note the difference between strains, sprains, and tears. A sprain is an injury to a ligament, specifically overstretching or tearing. A strain is an overstretching or tearing injury involving a muscle or tendon. Lastly, a tear can involve a ligament, muscle or tendon and is defined by the separation of fibrous tissue, usually from overstretching. In conclusion, a tear is more severe sprain or strain.
The most common type of rotator cuff injury is a tear. This injury occurs more often in patients over the age of 40, athletes playing sports such as baseball and tennis, and also people who have jobs that require a lot of overhead shoulder activity such as painting. Rotator cuff tears can occur from day to day wear and tear as well. Although sometimes asymptomatic, rotator cuff tears are one of the most common sources of shoulder pain (Murrell, 2001). The structure that is injured most often in the rotator cuff is the supraspinatus tendon, and can also lead to overcompensation of other tendons, making them more susceptible to damage and injury as well. In addition to overcompensation of other tendons making up the rotator cuff, muscles that protect the shoulder and aid in movement, such as the coracobrachialis, deltoid, latissimus dorsi and pectoralis major can also be affected. There are a couple different types of tears. Like the name suggests, a partial tear is an injury that results in the incomplete tearing of a tendon. Secondly, the full-thickness tear is considered a complete tear in which the tendon becomes unattached from the bone.
Mechanism of Injury
The two main causes of rotator cuff tears are degeneration and injury. An acute tear can occur from injury of the shoulder, such as lifting a heavy object or a sudden forceful movement of the shoulder. Acute tears are likely to occur alongside another injury involving the shoulder, such as a broken or fractured collarbone or a dislocated shoulder (Ortho Info, N.D.). A degenerative tear of the rotator cuff results from the constant wear on the shoulder and usually occurs as aging is happening. There are several factors, including repetitive stress, lack of blood supply and bone spurs that result, or contribute, to chronic rotator cuff tears (Ortho Info, N.D.). Since a majority of rotator cuff tears are a result of degeneration, adults over the age of 40 are at greater risk. On the other hand, people who perform overhead activities and athletes are also at a greater risk for tears.
Evaluation
The pain following a rotator cuff injury can either be symptomatic or asymptomatic. Some common symptoms of a rotator cuff tear can include pain at rest and at night, weakness when attempting to perform actions of the shoulder joint, and crepitus when moving the shoulder in certain positions (Ortho Info, N.D.). Immediate pain and weakness usually follows tears that result from a direct injury of the rotator cuff. Although pain and weakness can also be a symptom, degenerative injuries of the rotator cuff tend to begin with much less severe symptoms. The pain level of the patient can vary by person and also by injury. The pain may be anywhere on a spectrum from mild to severe. Once the pain is noticeable at rest and over-the-counter medications no longer alleviate pain, more intervention is recommended.
Upon the initial diagnosis by the professional, physical examinations will take place to attempt to locate a deformity and to locate areas of pain. A rotator cuff tear is usually not accompanied by bruising or discoloration unless the shoulder joint has been dislocated. Additionally, the range of motion is tested as well as the strength of the shoulder. Most of the time, rotator cuff injury diagnoses are assisted with the imagery from X-rays and magnetic resonance imaging (MRI, or ultrasounds). X-rays are usually the first, and primary form of imagery used. Since the x-ray cannot display tissues of the shoulder, such tests such as an MRI or ultrasound would be used. These two types of tests provide information about the location, age, and size of the tear.
Along with testing using imagery and physical procedures, professionals may also rule out other problems that could have be happening in the shoulder area. The neck may be tested to make sure that the problem isn’t caused by a pinched nerve and also to make sure the problem isn’t happening because of arthritis in the shoulder joint. The main differential diagnosis of a torn shoulder tendon occurs with the specific tendon being involved. Since there are four muscles that create the rotator cuff, there are more than one tendons that could be affected. It is important to locate the tear of the specific tendon in order to ensure that the most effective treatment plan is put in place.
Rehabilitation
Depending on the injury that causes the tear (degenerative or acute), precautions could be taken to avoid or lessen the probability that the injury occurs. Avoiding constant activity that cause wear and tear can be beneficial. The type of injury depends on what type of procedure necessary to repair the damage. There are two different treatment options: surgical and nonsurgical.
During the surgical treatment of a rotator cuff tear, the tendon is reattached to the head of the humerus. Surgery usually is considered if the pain and symptoms don’t improve from nonsurgical treatment plans. Additionally, if symptoms have lasted for nearly a year, there is a large tear or significant function loss in the shoulder, surgery would also be implemented. The three main types of surgical repair are open repair, all-arthroscopic repair, and mini-open repair. Open repair is a more traditional surgery in which the deltoid is detached in order to reattach the torn tendon. All-arthroscopic repair uses a small camera to provide imagery during the procedure and is considered the least invasive. Lastly, mini-open repair is the procedure in which a small incision is made and the tendon is repaired. This type of repair usually follows all-arthroscopic repair.
Nonsurgical procedures include rest, modification of activity, medication (specifically nonsteroidal anti-inflammatory drugs), physical therapy, and steroid injections. A majority of rotator cuff tears are treated with nonsurgical treatment and more often than not, the pain and function of the shoulder improves. There are advantages and disadvantages of nonsteroidal treatment when treating a tear in the rotator cuff. A couple advantages of avoiding surgical treatment include preventing infection, permanent stiffness, anesthesia complications, and lengthy recovery times (Kuhn, 2011). On the other hand, a couple disadvantages of nonsurgical treatment includes the size of the tear may increase with time and physical activity is limited during the recovery time period.
Within the spectrum of nonsurgical procedures, physical therapy is used to improve the function of the rotator cuff. Additionally, physical therapy is used after surgical procedures as well. The muscles and tendons can be strengthened and stretched with motions such as the pendulum swing, flexion stretch, prone rowing, prone horizontal abduction, side lying external rotation, and posterior capsule stretch (Ortho Info, N.D.). Although these movements are used following a rotator cuff tear, they are helpful for a more minor injury, such as a sprain or strain. The main difference between management of a rotator cuff injury at different stages would be the amount and frequency of physical therapy.
After intervention mechanisms are put in place, rehabilitation can occur. After approximately 4-6 weeks, the shoulder can start to withstand some physical activity. As physical therapy is performed, the muscles of the shoulder are strengthened. Although physical activity can occur at this time, full recovery time takes several months and repetitive therapy. Once the patient is completely recovered, a sport or other physical activity can be resumed.