- Include the anatomy (bones/muscles) and function of the area shoulder.
2. Include a minimum of 4 common injuries to the shoulder.
3. Describe how these injuries occur (mechanism); how each injury is diagnosed; how each injury would be treated (treatment protocol); and the rehabilitation.
4. Also include the length of time needed for full recovery and any preventative measures that can be taken.
5. Paper should be double-spaced using 12 point New Times Roman type with 1 – 1.5-inch margins.
6. Site at least 4 references using APA style.
The shoulder joint is one of the major joints of the upper portion of the body. At this joint, two major bones meet, namely the humerus and the Scapula (Shoulder blade). The shoulder joint is a ball-and-socket type of joint (enarthrodial joint). The articulating surfaces of the joint include the glenoid fossa of the scapula and the hemispherical head of the Humerus. The shoulder joint is a good example of biomechanical mobility, as although several bones meet in the joint, several movements are enabled in it.
Besides, specialized tendon tissues are present which help to protect the joint from injury. The ligaments present in the joint are four in number and include the articular capsule, the glenohumeral, the coracohumeral and the transverse humeral. These ligaments do not maintain contact between the glenoid fossa and the head of the humerus, but in fact limit the movement of the humerus.
The glenoid fossa can be moved a great distance from the humerus. Both the humerus and the glenoid fossa contain articular surfaces. The humerus has an articular surface that is thicker at the center and thinner at the margins. On the other hand, the glenoid fossa has a articular cartilage that is thicker at the margins and thinner at the center (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
The articular capsule forms a strong covering for the shoulder joint. Above it is attached to the glenoid fossa and below it is attached to the humerus at the neck. The joint seems to be thicker in the above and the lower regions compared to the center. The joint is loose and the bones do not tend to be in contact with each other. The joint can be separated at a distance of 2.5 cm. Several other accessory attachments are present (such as the supraspinous, the long head of the triceps brachii, the Teres minor and infraspinous tendons and by the tendons of the supraspinous. The articular capsules contain about three openings that help to communicate for several bursae and tendons (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
The coracohumeral ligament is present in the upper portion of the capsule and appears like a sheet-like structure. It connects the coracoid process to the humerus, and also unites with the Supraspinous. The front and back borders of the capsule are free (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
The Glenohumeral ligaments are three in number and help to reinforce the capsule. They connect different portions of the glenoid fossa to the head of the humerus. The first one extends from the medial edge of the glenoid fossa to the lesser tubercle of the humerus. The second one extends from the region below the glenoid fossa to the region under the anatomical neck of the humerus. The third extends from the apex of the glenoid fossa to the small depression present above the lesser tubercle of the humerus (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
The transverse humeral ligament connects the greater tubercle of the humerus to the lesser tubercle. The Glenoid labrum is a fibrous tissue It is connected to the glenoid cavity (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).]
The synovial membrane is presented on the inner margin of the glenoid fossa and the inner lining of the capsule. It is also present on the head of the humerus and the anatomical neck of the bone. A portion of the tendon of the head of the Biceps brachii is covered in a sheath that contains the synovial membrane (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
In the shoulder joint, Bursae is present in several regions. In the region present between the tendon of the Subscapularis and the capsule, prominent bursae are located. Another bursa is present between the tendon of the Infrascapularis and the capsule. These two bursae communicate with the joint. Between Deltoideus and the capsule another bursae is located that does not communicate with the joint. The other bursa present in the shoulder joint includes ones present between the capsule and the coracoid process, below the Coracobranchialis, between the long head of the Triceps and the Teres major and along the tendon of the Latissimus dorsi (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
In the shoulder region, several muscles are present. These include the Supraspinatus, Infraspinatus, Teres major, Deltoideus and the Triceps. The Supraspinatus is present within the joint in a superior and anterior region. In the inferior region of the shoulder joint, the long head of the Triceps brachii is present. In the posterior region, the Teres minor and the Infraspinatus is present. The joint is covered by the Deltoideus in the anterior, posterior and the lateral regions (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
In the shoulder joint, a range of movements can be expected. The Pectoralis major, the Deltoideus, Coracobranchialis, Biceps brachii, Latissimus dorsi, Teres Major, Triceps brachii, Infraspinatus, Subscapularis, etc help in the movement of the shoulder joint. Several movements such as flexion, extension, circumduction, rotation, abduction and adduction are enabled. Flexion and extension of the humerus helps in the movement of the shoulder joint. Many muscles such as the Pectoralis major, Delotideus, Coracobranchialis, Latissimus dorsi, Teres major, Triceps brachii, etc, help in the movement.
The capsule of the shoulder joint tends to remain loose and is intimately connected to the muscles, which are attached to the head of the humerus. The tendon of the long head of the biceps brachii is attached to the joint in a rather peculiar manner. The articular surface of the head of the humerus is larger than the glenoid fossa of the joint. Besides, as the capsule of the joint is loose, free movements can occur in several directions. The Acromion and the clavicle (collar bone) forms joints the clavicle and with each other. The Acromio-Clavicular joint helps to connect the clavicle to the scapula. The Acromion is actually formed by the extension of the scapula to form a roof like structure. The acromio-clavicular and the sternoclavicular joints supplement the motion of the shoulder joint.
The capsule is loose and does not control the movements of the joint. Several muscles such as the Trapzius, Levator scapulae, Rhomboidei, Pectoralis minor, Sub clavicle, Serratus anterior, Pectoralis major, etc, help in the movement of the scapula in a upward, backward, downward, forward, etc, regions. The muscles of the shoulder joint especially the Supraspinatus, Infraspinatus, Teres minor and Subscapularis have their tendons closely attached to the capsule. This permits the muscles to act as elastic ligaments of the joint (Grays Anatomy, 2005, & Reading Shoulder unit, 2004).
Complete and partial dislocation of the shoulder joint is a condition in which the bones that form the normal joint are displaced and disarranged to various extents. It occurs when the bones that form the normal shoulder joint are moved apart. Shoulder joint dislocations include about 50 % of all the dislocations that are present in the body. Most to the dislocations occur in teenager and young adults. Depending on the extent of the dislocations, it can be classified into two, namely partial dislocation (subluxation) and complete dislocation (luxation). In partial dislocation, the head of the humerus is partially outside the glenoid fossa, whereas in complete dislocation, the head is completely outside the glenoid fossa.
A dislocation can occur in several directions including anteriorly (which is more common) and posteriorly. The anterior dislocation is frequently known as ‘subcoracoid dislocation’. This is because; the head of the humerus lies in the region below the coracoid process following the trauma. An individual having bony lesions within the socket or the glenoid fossa of the shoulder joint is at a high risk of developing frequent shoulder dislocations. This condition is frequently known as ‘shoulder instability’ (Adams, 1999, Solomon, 2001 & Kessel, 2000).
Shoulder joint dislocation can be caused due to a number of reasons including: –
- Sports trauma (especially cricket, football, motorsports, contact sports, hockey, etc).
- A hereditary factor is also present. It may make the shoulder joint more frequently dislocate
- A fall on the stretched out arm
- Sudden twisting of the arms
- Direct trauma to the joint
- Electric shocks and seizures
A person with a dislocation of the shoulder joint would have several symptoms such as pain, reduction of the movement of the joint, muscle spasms, poor outline of the joint, presence of a depression on palpation, etc. Sensations may also be affected in the upper portions of the arm due to compression of the nerves. An individual with a dislocated shoulder is typically seen nervous, confused, and supporting the shoulder joint. The pain is excoriating during movement. Anterior shoulder dislocations are more likely to be detected compared to the posterior shoulder dislocations. In posterior shoulder dislocations, the outline of the joint seems to be flattened and remains stuck in an inward rotation position.
The history (of trauma), signs, symptoms, physical examination, X-rays, CT Scans, MRI scans, etc, help in the diagnosis of the shoulder joint. Imaging techniques help to confirm the dislocation by the demonstration of the head of the humerus outside the glenoid fossa. Usually, X-rays are taken from the front and the back. A dislocated shoulder joint is treated by reduction and immobilization. The dislocated joint should be reduced manually as fast as possible. Due to the severe pain, anesthesia may be required during the reduction process. Following this a simple sling needs to be worn for a few days in order to help in the healing.
The orthopedic surgeon would usually close the joint using closed reduction techniques such as Hippocratic method, Stimson’s method and Kocher’s method. These involve application of controlled traction forces against the arm. Meanwhile, a counter force is applied on the body.
During the entire process, X-rays are taken to ensure that the joint is reduced. Once the joint is reduced, a simple sling needs to be worn for at least 21 days. Exercises should be performed in the shoulder joint, as early as possible, to ensure that the healing process is proper. In case closed reduction is unable to reduce the dislocation, open reduction may be required. It is open performed in individuals having sports injury, to ensure accurate reduction. Individuals involved in contact sports need to wear protective clothing and gear (Adams, 1999, Solomon, 2001 & Kessel, 2000).
Another injury quite common and serious involving the shoulder joint is the fracture of the bones of the shoulder joint including the scapula and/or the humerus (including the head or the shaft). The scapula is one of the less fractured joints, as it is well protected by several muscles present in the region.
Usually, the fractures tend to occur in the neck and the body of the scapula, and less often in glenoid rim, coracoid and the Acromion regions. Fracture of the humerus is more common seen in middle-aged individuals and in children. Women suffering from bone-degenerative disorders such as osteoporosis are at a high risk of developing the disorder (Crenshaw, 1992 & Zuckerman, 1996). Fractures of the shoulder joint can be caused due to a number of reasons including: –
- Road-traffic accidents
- Fall on the shoulders
- Direct trauma
- Falling on a stretched out hand
- Application of twisting forces
The symptoms that can develop following fracture of the shoulder joint include: –
- Severe pain in the shoulder joint and the upper arm, especially on moving or touching
- Swelling in the affected region
- Presence of a deformity of the bone, that can be felt during palpation
- Abrasions and damage of the skin present in the shoulder joint
- Impaction of one fractured bone into another
- Compression of the brachial plexus of nerves resulting in the development of severe symptoms
- Shortening of the arms
- Difficult in moving the wrists, fingers, etc
The History, signs, symptoms, physical examination, X-rays, CT scans and MRI scans helps in the diagnosis of Shoulder joint fractures. The X-rays help to determine a loss of the continuity of the bone. X-rays may be required from several directions including front, back and the side views. CT scans can help detect glenoid rim fractures. A process of reduction and immobolisation treats shoulder joint fractures. The scapula is one joint may get shattered. A sling needs to be worn for about one week to three weeks in such cases. The individual should exercise the fractured joint as early as possible in order to ensure that full movement is recovered.
It may take about a year, for the normal movements to return in the shoulder joint. In certain cases, the fractured portion needs to be fixed using internal fixation devices such as plates and screws. Following the fracture of the shoulder joint, an individual may require administration of an analgesic in order to reduce the pain. In case of simple fractures of the humerus, closed reduction and immobilization would be required.
However, if the joint is severely fractured in several regions, then open reduction along with fixation may be required. Sometimes, the head of the humerus may have to be replaced with prosthesis. During the reduction of the fracture, a traction force may have to be applied on the hand, and a counter-traction force would have to be applied on the body. Immobilization may also be needed with plaster cast for a few weeks. Shattering of the humerus may require fixation with external devices (metal bars and pins) (Crenshaw, 1992 & Zuckerman, 1996).
Rotator–cuff is a tissue present in the shoulder region that forms the upper portion of the capsule of the shoulder joint. It is derived from the tendons that arise from the shoulder blade. It helps in the movement of the humerus in the glenoid fossa by stabilizing this joint. It is supported by four muscles namely Supraspinatus, Infraspinatus, Teres minor and the Subscapularis. The rotator cuff may be involved with several injuries including tear, rupture, inflammation, etc. It usually occurs in middle-aged and elderly individuals (Mayo clinic, 2001 & Turek, 2002). It may be related to a number of causes including: –
- Contact sports
- Road traffic accidents
- Repetitive overhead injuries
- Age-related injuries
- Lifting of heavy weights
Individuals with rotator cuff injuries develop several symptoms including pain in the shoulders, pain during night times, tenderness, cracking sounds on moving the arm, reduced movements of the shoulder, tenderness, weakening of the muscles, etc. The individual experiences difficulties especially on performing overhead activities. The history, symptoms, signs, physical examination, X-rays, arthrography, MRI scans and ultrasound help to make the diagnosis of the condition. X-rays help in the initial stages of the injury and to determine any changes in the bone. MRI scans and arthrography help to determine a rupture or tear of the rotator cuff. MRI scans is a non-invasive procedure and provides precise findings.
Rotator cuff injuries that are partial are treated by conservative means including application of ice, rest, immobilization, physiotherapy, exercises, corticosteroid injections, ultrasound therapy, etc. Rest and immobilization may be required for about three to four weeks. Partial injuries do not require surgery. However, if these injuries do not respond to conservative therapy, surgery may be required. One of the modern surgical aides utilized is arthroscopy. This helps to repair the defected rotator-cuff tissues.
It helps to remove the disease tissues and also smoothen the bones. The healing and stay in the hospital is much faster through arthroscopy surgery. Arthroscopy surgery may also be required to treat complete ruptures of the rotator cuff. Rotator-cuff injuries should be prevented by exercising the shoulder in order to improve the muscle strength, avoid overhead movements repetitively and preventing lifting of heavy weights (Mayo clinic, 2001 & Turek, 2002).
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Crenshaw, A. H. (1992). Fractures of Shoulder Girdle, Arm, and Forearm, In. Crenshaw, A. H. (Eds). Campbell’s Operative Orthopaedics: Vol. 2, St. Louis: Mosby.
Grays Anatomy (2005). Humeral Articulation or Shoulder-joint, Retrieved on November 15, 2007, from Bartelby Web site: http://www.bartleby.com/107/83.html
Grays Anatomy (2005). The Scapula, Retrieved on November 15, 2007, from Bartelby Web site: http://www.bartleby.com/107/50.html
Kessel, L. (2000), Injuries to The shoulder, In. Wilson, J.N. (Eds), Watson-Jones Fractures and Joint Injuries Vol: 2, 6th ed, Edinburgh: Churchill Livingstone.
Mayo Clinic (2001), Treatment of Rotator Cuff Injury at Mayo Clinic in Jacksonville, Retrieved on November 15, 2007, from Mayo Clinic Web site: http://www.mayoclinic.org/rotatorcuffinjury-jax/
Reading Shoulder Unit (2004). Shoulder Anatomy…, Retrieved on November 15, 2007, from YSL Studio Web site: http://www.readingshoulderunit.com/shoulder_anatomy.htm
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Turek, S. L. (2002), Orthopedics: Principles and Their Application vol. 2, 4th ed, Philadelphia: Lippincott-Raven Publishers.
Zuckerman, J. D. & Koval, K. J. (1996). Fractures of the shaft of the Humerus, In. Rockwood, C. A., Bucholz, R. W. & Green, D. P. (Eds), Rockwood’s and Green’s Fractures in Adults: Vol. 1, 4th ed, Philadelphia: Lippincott Raven Publishers.