Definitions of Rotator Cuff Tears - Essay Example

Rotator Cuff Tears Introduction Rotator cuff tears has been presented in the essay in conjunction with the anatomy of the shoulder, muscles, joints and tendons, basic shoulder biomechanics, definition and anatomy of rotator cuff and rotator cuff tears, its symptoms, causes, risk factors, type of injuries and the treatment available for the torn rotator cuff, with relative pictures as needed. The essay cited the works of some medical practitioners and/or authors of articles on rotator cuff tears from different sources that include internet sites, books on practical orthopedics, medical surgical nursing and diagnosis of bone and joint disorder,, and the encyclopedia of medicine. The reader will definitely find the essay on rotator cuff tears a bit comprehensive and therefore a worthwhile reading experience. Anatomy of the Shoulder and Rotator Cuff The shoulder (Mercier 28-29) is composed of three bones: the scapula,, the clavicle and the humerus. The scapula is a thin bone that articulates widely and closely with the posterior chest wall. It also articulates with the humerus by way of a small, shallow, glenoid cavity and with the clavicle at the acromion process. The clavicle and scapula are suspended from the cervical and thoracic vertebrae by the trapezius, levator scapula, and rhomboid muscles. Four articulations constitute the shoulder joint: the glenohumeral, scapulothoracic, acromioclavicular, and sternoclavicular joints. The stability of these joints is provided by a series of ligaments and muscles. Motion of the arm results from the coordinated efforts of several muscles. With the irritation of shoulder motion, the scapula is first stabilized. The muscles of the rotator (musculotendinous) cuff then steady the humeral head in the glenoid cavity and cause it to descent. Elevation of the arm results from a combination of scapulothoracic and glenohumeral joint movements. One third of total shoulder abduction is provided by forward and lateral movement of the scapula. The remaining two thirds occurs at the glenohumeral joint through progressively increasing activity of the deltoid and supraspinatus muscles. Thus, even in the complete absence of glenohumeral motion, scapulothoracic movement can still abduct the arm approximately 600 to 700. The muscle of the rotator cuff (supraspinatus, teres minor, infraspinatus, subscapularis) are separated from the overlying "coracoacromial arch" by two bursae, the subdeltoid and the subcoracoid. These bursae frequently communicate and are affected by lesions of the musculotendinous cuff, acromioclavicular joint, and adjacent structures. They are frequently referred to as the subacromial bursa. Primary diseases of this bursa are rare, although secondary involvement is quite common. The shoulder (Matt, July 23, 2002) is made up of three bones: the scapula (shoulder blade), the humerus (upper arm bone), and the clavicle (collar bone). The rotator cuff connects the humerus to the scapula. The rotator cup is formed by the tendons of four muscles: the supraspinatus, infraspinatus, teres minor, and subscapularis. Tendons attach muscle to the bones. Muscles move the bones by pulling on the tendons. The rotator cuff helps raise and rotate the arm. As the arm is raised, the rotator cuff also keeps the humerus tightly in the socket of the scapula. The upper part of the scapula that makes up the roof of the shoulder is called acromion, A bursa is located between the acromion and the rotator cuff tendons. A bursa is a lubricated sac of tissue that cuts down on the friction between two moving parts. Bursae are located all over the body where tissue must rub against each other. In this case, the bursa protects the acromion and the rotator cuff from grinding against each other. The Encyclopedia of Medicine explained the movements of the shoulder joint as follows: "The shoulder joint is a ball-and-socket joint which allows 3600 of movement to give maximum flexibility. In addition to enabling these movements, the muscles of the pectoral girdle add stability. The movements of the shoulder joint take place around three axes: a horizontal axis through the center of the glenoid fossa; axis perpendicular to this (front back) through the humeral head; and a third axis running vertically through the shaft of the humerus. These give the axes of flexion and extension, adduction (movement towards the body) and abduction (movement away from the body), and medial (internal) and lateral (externel) rotation respectively. A combination of these movements can allow a circular motion of the limb called circumduction. Many of the muscles involved in these movements are attached to the pectoral girdle (the clavicle and scapulae). The scapula has muscles attached to its rear and front surfaces and the coracoid process, a bony projectioon. Some muscles arise directly from the trunk (pectoralis major and lattisimus dorsi). Other muscles influence the movement of the humerus even though they are not attached to it directly (such as trapezius). They do this by moving the scapula, and hence the shoulder joint." The rotator cuff muscles (Wikipedia), a group of four muscles that surround the shoulder are the supraspinatus, infraspinatus, teres minor, and subscapularis. The four rotator cuff muscle tendons combine to form a broad, conjoined tendon called the rotator cuff tendon, and insert onto the bone of the humeral head in the shoulder. The humeral head is the ball side of the "ball and socket" shoulder joint; the socket is called the glenoid fossa. A tendon (or sinew) is a tough band of fibrous connective tissue that usually connects muscle to bone and is built to withhold tension. Tendons are similar to ligaments except that ligaments join one bone to another. Tendons and muscle work together and can only exert a pulling force. The rotator cuff (rotor cuff) is an anatomical term given to the group of muscles and their tendons that act to stabilize the shoulder. Along with the teres major and the deltoid the four muscles of the rotator cuff make up the six scapulohumeral (those that connect to the humerus and scapula) muscles of the human body. The supraspinatus is a relatively small muscle of the upper limb that takes its name from its origin from the supraspinous fossa superior to the spine of the scapula. It is one of the four rotator cup muscles and also abducts the arm at the shoulder. The spine of the scapula separates the supraspinatus muscle from the infraspinatus muscle, which originates below the spine. The infraspinatus muscle is a thick triangular muscle, which occupies the chief part of the infraspinatus fossa. The teres minor is a narrow, elongated muscle of the rotator cuff. The subscapularis is a large triangular muscle which fills the subscapular fossa. The rotator cuff (Cluett) helps to lift and rotate the arm and to stabilize the ball of the shoulder within the joint. The rotator cuff is made up of four muscles and their tendons. These combine to form a "cuff" over the upper end of the arm (head of humerus). The four muscles of the cuff (supraspinatus, infraspinatus, subscapularis, and teres minor muscles) are attached to the scapula on the back through a single tendon unnit. The unit is attached on the side and front of the shoulder on the greater tuberosity of the humerus. The Encyclopedia of Medicine explained the rotation of the arm and "rotator cuff" as follows: "The rotator cuff muscle include subscapularis, supraspinatus, infraspinatus and teres minor. These muscle act to strengthen and increase teh stability of the shoulder joint. They also act individually to move the humerus and upper arm. The pectralis major, anterior fibres of deltoid, teres major and latissimus dorsi muscle also cause medial rotation of the humerus. The most powerful medial rotator, however is subscapularies. This muscle occupies the entire front surface of the scapula, and attaches to the joint capsule around the lesser tuberosity of the humerus. Subscapularis is one of a set of four short muscles, collectively called the "rotator cuff", which attack to and strengthen the joint capsule. In addition, they pull the humerus into the socket of the joint (glenoid fossa), increasing contact of the bony elements. This is the most important factor contributing to the stability of the joint. The other muscles of the group are supraspinatus, infraspinatus and teres minor. These latter three muscles attach to the three facets on the greater tuberosity of the humerus. Infraspinatus and teres minor are lateral rotators of the shoulder joint, together with the posterior fibres of the deltoid. Injury to the rotator cuff muscles is disabling because the stability of the humerus in the joint is lost. The other muscles of the arm lose the ability to move the humerus correctly, resulting in dislocation of the joints." Basic Shoulder Biomechanics (Joint Pain Info, 2008) There are three joints in the shoulder complex. The main joint is the glenohumeral joint. It is a ball and socket (modified ovoid) joint and it is the most mobile joint in the body. The top of the humerus is shaped like a ball and it sits in a socket on the end of the scapula. The ball is called the head of the humerus and the socket is called the glenoid fossa, hence the term "glenohumeral" joint. The other two joints in the shoulder complex are the sternoclavicular joint and the acromioclavicular joint. The sternoclavicular joint connects the inner (medial) part of the collarbone (clavicle) to the breastbone (sternum). The acromioclavicular joint connects the outer (lateral) part of the clavicle to a projection at the top of the shoulder blade (scapula) called the acromion process. The scapula sits on the ribs and moves as the arm moves. The movements of the glenohumeral joint include forward lifting of the arm (flexion), backward lifting of the arm (extension), inward (internal) rotation, outward (external) rotation, movement of the arm away from the body (abduction) and movement of the arm towards the body (adduction). Movement at the glenohumeral joint requires motion at the other joints of the shoulder complex. The coordinated movement of these joints during arm movement is referred to as the scapulo-humeral rhythm. The scapulo-humeral rhythm describes movement that occurs at the glenohumeral joint compared to movement that occurs at the other shoulder complex joints, the sternoclavicular, the acromioclavicular and the scapulothoracic joints. The scapulothoracic joint is not a true joint but it describes movement of the scapula against the thoracic wall during arm movement. The scapulo-humeral rhythm allows the shoulder to move through its full range of movement and it allows the head of the humerus to be centered within the glenoid fossa. For every 15 degrees of shoulder abduction, 10 degrees occurs at the glenohumeral joint and 5 degrees occurs at the scapulothoracic joint. For 180 degrees of shoulder abduction, 120 degrees occurs at the glenohumeral joint and 60 degrees occurs at the scapulothoracic joint. If there are changes to the scapulo-humeral rhythm, the head of the humerus does not remain centered and it can lead to problems with the rotator cuff tendons such as tendonitis or rotator cuff impingement. The muscles of the shoulder complex provide stability and movement. During shoulder movements such as lifting, certain muscle groups help to move the shoulder, while other muscle groups help to stabilize the shoulder complex. Much of the stability in the shoulder complex is provided by this muscular coordination. Poor posture, muscle weakness or ligament injury can lead to abnormal biomechanics of the shoulder, which can result in abnormal forces in the shoulder. Over time these abnormal forces can cause injury to the soft tissues or the articular cartilage of the glenohumeral joint. Disorders of the Rotator Cuff as explained by Mercier (30-34): "The tendons of the rotary cuff muscles fused together near their insertions into the tuberosities of the humerus to form a muscolotendinous cuff. With advancing age and repeated trauma, these tendons, especially the supraspinatus, undergo degeneration. This is most severe near the tendon insertion. Secondary changes, in the form of thickening and chronic inflammation, frequently develop in the overlying bursa. A great deal of difficulty is encountered in diagnosing nonarticular soft tissue lesions of the shoulder. Tendinitis,, bursitis, complete and incomplete rotator cuff ruptures, calcific deposits, and other lesions are all capable of producing similar signs and symptoms. A variety of terms have developed to describe these diseases: supraspinatus syndrome, chronic impingement syndrome, painful arc syndrome, and internal derangement of the subcromial joint. The treatment for all of these lesions tends to be similar except foe complete rupture of the capsular rotator muscles, which causes loss of motor function. Surgical repair is frequently necessary for this lesion. At any age, a chronic strain of the musculotendinous unit may develop. Small tears of the rotator cuff any even be produces in the young athlete of laborer from repetitive use. Scarring and thickening of the involved area of tendon occurs with secondary irritation of the overlying bursa. Thickening of all of these tissues decreases the distance between the cuff and the overlying coracoacromial arch. Pain and crepitus may be noted when motions of the arm squeeze and pinch these tissues between the humerus and the overlying arch. Ruptures of the rotator cuff results from continued deterioration and degeneration. The tear may be partial or complete. Ruptures are uncommon before age of 40, but may occur in the young athlete secondary to a sudden forceful motion of the shoulder. Calcium deposits in the rotator cuff tendon are frequent causes of pain and stiffness in the shoulder. These deposits result from degenerative changes in the same area where ruptures take place and are most frequently found in the supraspinatus tendon. Many of them remain small and deep in the tendon and, consequently, do not irritate the overlying bursa. Others slowly increase in size until they contact the bursa and produce an inflammatory reaction and swelling of the bursa. Impingement of these swollen tissues on the overlying coracoacromial arch may increase the inflammation and pain. intermittent mechanical locking of the shoulder may even occur." Definitions of Rotator Cuff Tears Rotator cuff tear as explained by Donald Resnick (2314-2316): The rotator cuff, composed of the teres minor, infraspinatus, supraspinatus, and subscapulairs muscles, is a common site of abnormality. Acute or chronic tears of this structure may be encountered. Traumatically induced tears can be associated with pain and full passive range of motion. the presence of inflammation or degeneration of the cuff accentuates its vulnerability to rupture. The torn tendon retracts and becomes ineffective in its normal action as an antagonist to the upward pull of the deltoid muscle. This loss of function in combination with a decrease in the soft tissue mass between humerus and acromion allows the humeral head to become juxtaposed to the undersurface of the acromion process. This superior displacement, however, is not constant, so that it is important to reorganize additional radiographic manifestations that accompany rotator cuff injuries. The incidence of these manifestations is greater in cases on chronic rotator cuff tears than in acute injury. Rotator cuff tears (Wikipedia 8 Feb. 2008) are tears of one or more of the four tendons of the rotator cuffs muscles. Rotator cuff tears are among the most common conditions affecting the shoulder. The tendons of the rotator cuff, not the muscles, are most commonly torn. Of the four tendons, the supraspinatus is most frequently torn; the tear usually occurs at its point of insertion onto the humeral head at the greatest tuberosity. Rotator cuff tear (Cluett) is a common cause of pain and disability among adults. Most tears occur in the supraspinatus muscle but ohter parts os the cuff may be involved. Rotator Cuff Tears Symptoms of Rotator Cuff Tears According to Cluett, the most common symptom of a rotator cuff tear is pain. It is often difficult for a patient to localize the pain to a specific area, rather it is described as a generalized discomfort that is exacerbated with specific movements of the shoulder. Pain is often felt over the outside of the shoulder, or even down the arm to the elbow. Depending on the severity of the rotator cuff tear, there may also be a loss of motion. If the injury is an incomplete, or partial tear, pain will likely be the most prominent symptom; decreased strength may be demonstrated, but is usually not the patient's primary complaint. In a complete rotator cuff tear, the patient will likely be unable to move the shoulder through some normal motions. The diagnosis of a rotator cuff tear is best made by a physical exam where your doctor can isolate and test the function of the specific muscles that for the rotator cuff. American Academy of Orthopaedic Surgeons (Website 10/2007) noted that some of the signs of a rotator cuff tear includes: Atrophy or thinning of the muscles about the shoulder, pain when lifting the arm, pain when lowering the arm from a fully raised position, weakness when lifting or rotating the arm, and crepitus or crackling sensation when moving the shoulder in certain positions. Symptoms of a rotator cuff tear may develop right away after a trauma, such as a lifting injury or fall on the affected arms. When the tear occurs with an injury, there maybe sudden acute pain, a snapping sensation and an immediate weakness of the arm. Symptoms may also develop gradually with repetitive overhead activity or following long-term wear. Pain in the front of the shoulder radiate down the side of the arm. At first the pain may be wild and only present with overhead activities, such as reaching or lifting. It may be relieved by over-the-counter medication such as aspirin or ibuprofen. Over time, the pain may become noticeable at rest or with no activity at all. There may be pain when lying on the affected side at night. Cronin added that the most common symptoms of a partial tear are: Pain when moving your arm against resistance, weakness in your shoulder, and stiffness and limited range of motion. Symptoms of a sudden, severe (acute) tear include: A popping sound or tearing sensation in your shoulder, immediate pain in your shoulder, weakness when lifting or rotating your arm,, limited range of motion and inability to raise your arm because of pain or weakness, s crackling sound in the shoulder when it is moved, and possibly, bruising in your shoulder or upper arm. A complete tear can be present without obvious symptoms, especially in an older adult who is not very active. In some cases, shoulder pain may be a sign of a more serious problem, such as a heart attack. Rotator cuff tears (Matt) cause pain and weakness in the affected shoulder. In some cases, a rotator cuff may tear only partially. The shoulder may be painful, but you can still move the arm in a normal range of motion. in general, the larger the tear,, the more weakness it causes. In other cases, the rotator cuff tendons completely ruptures. A complete tear makes it impossible to raise the arm away from your side by yourself. Most rotator cuff tears cause a vague pain in the shoulder area. They may also cause a catching sensation then you move your arm, most people say they can't sleep on the affected side due to the pain. Complete and incomplete tears of the rotator cuff as explained by Resnick (549-550): "Tears in the rotator cuff musculature may involve the entire thickness of the cuff (complete tear) or a portion of the cuff (incomplete or partial tear). In complete tear situation, abnormal communication exists between the glenohumeral joint cavity and the subcromial (subdeltoid) bursa. Contrast material can be identified within the bursa as a large collection superior and lateral to the greater tuberosity and adjacent to the undersurface of the acromion. The contrast material in the bursa is separated from the articular cavity by a lucency of varying size, representing the rotator cuff itself. If the musculature is atrophic, the lucency is small or even absent. In the presence of a complete rotator cuff tear, contrast material is identified as a "saddle-bag" radiodense area across the surgical neck of the humerus on the axillary view. In some patients with complete tears, the contrast material will pass from the subcromial bursa into the acromioclavicular joint. Utilizing double-contrast shoulder arthrography, the degree of degeneration of the torn rotator cuff can be recognized. Furthermore, the width of the tear itself is identified. The location of the disrupted tendons is apparent as the tendinous ends are coated by positive contrast material. In some patients, the torn rotator cuff tendons are either absent or consist of only a few small pieces, prohibiting adequate surgical repair or, at the very least, requiring an alternative method of surgery. Killoran and associates have emphasized three potential sources of error in the diagnosis of a complete rotator cuff tear: inadequate distribution of opaque material within the joint may prevent adequate visualization of the subacromial bursa; the contrast-filled sheath of the biceps tendon may project slightly lateral to the greater tuberosity on external rotation, simulating filling of the subacromial bursa; inadvertent bursal injection may simulate a complete tear unless one recognizes that the articular cavity is not opacified. An incomplete tear is a partial tear that may involve the deep surface of the rotator cuff, the superficial surface, or the interior substance of the tendon. Tears within the substance of the cuff will generally escape arthrographic detection but may not require operative repair. Tears involving the superior surface of the cuff will also not be demonstrated on glenohumeral joint arthrography, although they may rarely be seen with direct subacromial bursography. Tears on the inferior surface of the rotator cuff can be diagnosed on arthrography. In these cases, an ulcer-like circular or linear collection of contrast material may be identified above the opacified joint cavity, near the anatomic neck of the humerus. The intact superficial fibers prevent opacification of the subscromial bursa. A false negative arthrogram in the presence of a partial tear of the rotator cuff can indicate that the tear is too small for recognition or that a fibrous nodule has occluded the defect." What causes the rotator cuff to tear Matt explained that the rotator cuff tendons have areas of very low blood supply. The more blood supply a tissue has, the better and faster it can repair and maintain itself. The areas of poor blood supply in the rotator cuff make these tendons especially vulnerable to degeneration from aging. The degeneration of aging helps explain why the rotator cuff of such a common injury later in life. Rotator cuff tears usually occur in areas of the tendon that had low blood supply to begin with and then were further weakened by degeneration. This problem of degeneration may be accelerated by repeating the same types of shoulder motions. This can happen with overhand athletes, such as baseball pitches. But even doing routine chores like cleaning windows, washing and waxing cars, or painting can cause the rotator cuff to fatigue from overuse. Excessive force can tear weak rotator cuff tendons. This force can come from trying to catch a heavy falling object with the arm extended. The force can also be from a fall directly onto the shoulder. Sometimes injuries that tear the rotator cuff are painful, but sometimes they are not. Researchers estimate that up to 40 percent of people may have a mild rotator cuff tear without even knowing it. The typical patient with a rotator cuff tear is in late middle age and has had problems with the shoulder for some time. this patient then lifts a load or suffers an injury that tears the tendon. After the injury, the patient is unable to raise the arm. However, these injuries also occur in young people. Overuse or injury at any age can cause rotator cuff tears. Cluett said that the rotator cuff can be torn from a single traumatic injury. Patient often report recurrent shoulder pain for several months and a specific injury that triggered the onset of the pain. A cuff tear may also happen at the same time as another injury to the shoulder, such as fracture or dislocation. Most tears, however,, are the result of overuse of these muscles and tendons aver a period of years. people who are specially at risk for overuse are those who engage in repetitive overhead motions. These include participants on sports such as baseball, tennis, weight lifting, and rowing. Rotator cuff tears are most common in people who are over the age of 40. younger people tend to have rotator cuff tears following acute trauma or repetitive overhead work or sports activity. Rotator cuff tear may often happen as a result of wear and tear. Treatment of rotator cuff tears (Black 653) often begins conservatively with rest and sling support for the shoulder. Some physicians also advocate intra-articular injection of analgesics or steroids. When acute manifestations subside, the client should begin active exercises that address range of motion and strength en the rotator cup muscles. Exercise maybe preceded by application of heat and followed by ice if discomfort occurs. Surgery may be necessary to repair a tear in the rotator cuff. Post-operation management include instruction on the use of a shoulder immobilizer and introduction of a program of gentle exercise such as the pendulum shoulder movement. The neurovascular status of the affected area should be compared with the nonoperative arm. Pain management should also be a focus of postoperative care. According to Cedars-Sinai Health System the causes and risk factors for a rotator cuff tear are: Repetitive overhead motion, heavy lifting, trauma from excessive force such as a fall, degeneration due to aging or reduced blood flow to the tendons, narrowing of the space (acromioclavicular arch) between the collarbone (clavicle) and the top portion (acromion) of the shoulder bone (scapula) and rubbing of the cuff surface by the top of the shoulder bone. Works Cited Abrahams, Peter, consultant ed. "Atlas of the Body". Encyclopedia of Medicine. London: Brightstar Publishing, 2000. American Academy of Orthopaedic Surgeons. Website. Oct. 2007. . Black, Joyce M. and Jane H. Hawks. Medical Surgical Nursing. Singapore. Elsevier PTE Ltd. 2005. Cedars-Sinai Health System. 2008. http://www.csmc.edu/6896.html. Cluett, Jonathan. "Rotator Cuff Tears". About, Inc. 01 December 2007.. Cronin, Colleen. "Symptoms of rotator cuff tears." Healthwise, Inc. 10 Feb 2006. . Image @ Medical Multimedia Group. . Farjo, Laith A. Advanced Orthopedic Specialist. 2006. http://www.advancedortho.net/pages/shoulder/rotator.htm. Matt. "Rotator Cuff Tears". 23 July 2002. . Mercier, Lannie R. The Practical Orthopedics. USA: Year Book Medical Publishers, 1980. Resnick, Donald and Gen Niwayama. ed. Diagnosis of Bone and Joint Disorder. D. Med., Sc. USA: W.B. Saunders Co. Vol. 2. 1981. Web.M.D., inc. 2005. http://www.emedicinehealth.com/rotator-cuff-injury/article-em.htm. Read More