The Shoulder Joint

Normal anatomy of the glenohumeral joint showing the bones, muscles, tendons, ligaments, and capsuie at the shouider in frontal section (A) and glenoid face (B) views. The superior (S), inferior (I), medial (M), lateral (L), anterior (A), and posterior (P) directions are also denoted on each view (images used with permission of Primal Pictures, Ltd., London). 

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The natural hip joint, like the shoulder joint, consists of a ball-and-socket connection. Many combinations of materials have been tried for this and other joints. In general metal-metal joints are unsatisfactory because of high corrosion and friction that result in joint immobilization. All ceramic joints often fracture too readily, and all plastic joints usually lack strength in at... 

Inman V.T., Saunders J.B. deCM, and Abbott L.C. 1944. Observations on the function of the shoulder joint. J. Bone Joint Surg. 26A 1. 

Horizontal abduction Horizontal Longitudinal Movement of the arm in a posterior direction away from the midhne of the body with the shoulder joint in 9C of either flexion or abduction. 

Swieszkowski et al. studied the use of PVA-C as cartilage replacement for the shoulder joint. PVA-C was used as the articular layer of the glenoid component. The mechanical effects of using this material in the glenoid component were evaluated and a model of the cryogel as a hyperelastic material was developed to allow design modifications to limit contact stress [96]. 

Fig. 2.15a,b. AP shoulder girdle. Centre Medial to the shoulder joint making sure the full length of the clavicle and scapula is demonstrated. Area imaged Full length of the clavicle, scapula, upper 1/3 of the humerus and the shoulder joint... 

The child is seated with the affected side against a table (younger children can sit on the carers knee). The height of the table is altered until the child is comfortably able to lean across the table. The arm on the side under examination is raised over a 45 angle pad and the child is encouraged to lean across the table to allow the shoulder joint to project clear of the rib cage over a cassette. The child is then encouraged to look away from the shoulder or tilt the head forward out of the radiation beam (Fig. 2.16)... 

Alternatively a small child may be placed supine on a table with the affected arm abducted. The cassette is placed either in the axilla or resting on the superior border of the shoulder depending on the size of the child. The X-ray tube is rotated into a horizontal position and is directed through the shoulder joint in either an infero-superior or supero-inferior direction. The child will often need to be raised on a pad to allow the X-ray tube to achieve this position. 

Fig. 2.16a,b. Axial shoulder. Centre Directly through the shoulder joint, a 5° angle along the lateral aspect of the humeral shaft towards the hand may be used. Area imaged The glenoid and proximal portion of the humerus... 

A 62-year-old man received an interscalene block with 30 ml of lidocaine 1% and 20 ml of bupivacaine 0.25% under light sedation, followed by general anesthesia. A catheter was inserted into the shoulder joint and a continuous infusion of bupivacaine 0.25% at 2 ml/ hour was started. At the end of the surgery 1 hour later he was still deeply anesthetized, with dilated pupils. Three hours after the interscalene block he began to respond and to breathe spontaneously, and his pupils normalized. 

This technique offers optimal cosmetic results, and there have been no restrictions in physical activity or movement of the shoulder joint (Fig. 4.67). 

Through the shoulder joint Through the bodies of the lumbar vertebrae Slightly posterior to the axis of the hip joint Slightly anterior to the axis of the knee joint... 

Total abduction of the shoulder joint can be divided into three phases. During the first phase (0 to 90 degrees), the supraspinatus and deltoid muscles are involved. At the beginning of the movement the supraspinatus is very efficient in abduction and in maintaining joint stability, whereas the deltoid is very inefficient and tends to produce superior dislocation. As abduction progresses, the deltoid s efficiency increases whereas that of the supraspinatus decreases. 

Total flexion of the shoulder joint can also be divided into three phases. In the first phase (0 to 60 degrees), the muscles used are the anterior fibers of the deltoid, the coracobrachialis, and the clavicular fibers of the pectoralis major. Motion is limited by the tension of the coracohu-meral ligament and by the resistance offered by the teres minor, teres major, and infraspinatus muscles. 

The accessory joints are the costostemcd joints anteriorly, especially those of the first and second ribs, and the costovertdrral joints posteriorly. The accessoryjoints are not anatomically involved in the shoulder joint or shoulder girdle, but dysfunction of these joints can Interfere with free shoulder motion. 

The Apley scratch test is a good method to test active range of motion. The patient is instructed to reach across his chest, over the shoulder, and touch the opposite scapula. Then he reaches behind his back and touches his opposite scapula. Finally, he reaches behind his head and touches the opposite scapula. These maneuvers actively test all the ranges of motion in the shoulder joint. If one of these maneuvers cannot be performed, it is then necessaiy to identify which shoulder motion is restricted and evaluate it more carefully. 

Note If the hypertonic muscle is located above the mid-line of the shoulder joint, the flexion used is reduced accordingly. If the hypertonic muscle is located below the mid-line of the shoulder joint, the flexion is increased, accordingly, above the 90 degrees. 

If the dysfunction is lateral to the middle of the shoulder joint, the final motions are abduction and external rotation. 

Note The amount of flexion and whether abduction-external rotation or adduction-internal rotation is applied will follow the same notes as for the shoulder joint. 

The first seven vertebrae, called cervical vertebrae, form the neck. Areas of the spine such as the neck, where flexible, can experience strains and sprains. The shoulder consists of a ball and socket joint where the ball of one bone fits into a hollow crevice of another. The shoulder joint allows movement and rotation of the arms inward, outward, forward, or backward. There are several different tendons attached to bones in the shoulder. Bursar reduces friction and cushions the tendons as they slide back and forth. The spine is a column of approximately 30 bones called vertebrae that run from the neck to the tailbone. These vertebrae stacked on top of one another in a shaped column form spinal joints, which move independently. Health spines contain three natural curves a forward curve in the neck, a backward curve in the chest area, and another forward curve in the lower back. The back s three natural curves should align correctly when ears, shoulders, and hips form a straight line. At the end of the spine, the vertebrae fuse together to form the sacrum and the tailbone. The lower back or lumbar area provides the workhorse capacity of the back. It carries most of the weight and load of the body. Aligning and supporting the lumbar curve properly helps prevent... 

Table 2 shows the value of torques obtained at the shoulder joint while the subject is performing the smash stroke and Fig. 2 illustrates e changes of torques on the joint in each position. 

During the execution of smash, the shoulder is in its extension movement in the force producing phase and reaches its maximum before contact. After impact the value of torque at the shoulder joint ceases and it continues in the follow through phase. 

The shoulder joint starts from lateral rotation and changes its rotation medially after the take-off phase. The shoulder continues to rotate medially during the airborne phase and at contact. During take-off, the shoulder gained the maximum force and hence produced the highest value of torque to ensure that the highest speed of the racket and accelerate the shuttlecock. 

Parsonage Turner syndrome) MR imaging appearance-report of three cases. Radiology 207 255-259 Hermann KA, Backhaus M, Schneider U et al (2003) Rheumatoid arthritis of the shoulder joint comparison of conventional radiography, ultrasound and dynamic contrast-enhanced magnetic resonance imaging. Arthritis Rheum 48 3338-3349... 

Jerosch J, Castro WH, Jantea C et al (1989) Possibilities of sonography in the diagnosis of instabilities of the shoulder joint. Ultraschall Med 10 202-205 Jerosch J, Marquardt M, Gortzen M (1990) Sonographic diagnosis of Hill-Sachs lesions in unstable shoulder joints. Ultraschall Med 1 251-253... 

O Connor EE, Dixon LB, Peabody T et al (2003) MRI of cystic and soft-tissue masses of the shoulder joint. AJR Am J Roentgenol 183 39-47... 

Patten RM, Mack LA, Wang KY et al (1992) Nondisplaced fractures of the greater tuberosity of the humerus sonographic detection. Radiology 182 201-204 Patton WC, McCluskey III (2001) Biceps tendinitis and subluxation. Clin Sports Med 20 505-529 Peetrons P, Rasmussen OS, Creteur V et al (2001) Ultrasound of the shoulder joint non rotator cuff lesions. Eur J Ultrasound 14 11-19... 

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