chapter 12 KNES 315 a

physical conditioning

strengthening programs should focus on muscles acting on both the GH and scapulothoracic region; strength in the infraspinatus, teres minor, and posterior shoulder musculature is necessary to: begin the cocking phase of throwing fix the shoulder girdle during the acceleration phase provide adequate muscle tension, with eccentric contractions, for smooth deceleration through the follow-through phase a weakened supraspinatus is present in many chronic shoulder problems, particularly among throwers; concentric and eccentric contractions with light resistance in the first 30 degrees of abduction can strengthen this muscle; strengthening the scapular stabilizers can be accomplished by doing push-ups or moving the arm through a resisted diagnoal pattern of exertional rotation and horizontal abduction 195

sternoclavicular joint sprain (anterior)

the SC joint is the main axis of rotation for movements of the clavicle and scapula; the majority of injuries result form compression related to a direct blow, as when a supine individual is landed on by another participant, or more commonly by indirect forces transmitted form a blow to the shoulder or a fall in an outstretched arm; the disruption typically drives the proximal clavicle superior, medial, and anteiror, disrupting the costoclavicular and SC ligaments and leading to anterior displacement 196

acromioclavicular joint

the ________________ consists of the articulation of the medial facet of the acromion process of the scapula with the distal clavicle; as an irregular, diarthrodial joint, limited motion is permitted in all three planes; the joint is enclosed by a capsule, although the capsule is thinner than that of the SC joint; the strong superior and inferior _______________ ligaments cross the joint, providing stability; the coracocacromial ligament, sometimes referred to as the arch ligament, also attaches to the inferior lip of the _____________________ to serve as a buffer between the rotator cuff muscles and the bony acromion process the close-packed position of the __________________ occurs when the humerus is abducted at 90 degrees; injuries to the AC joint are common in athletes involved in throwing and other overhead activities 189

shoulder

the ________________ is the most freely movable joint in the body, with the motion capability in all three planes; sagittal plane movements at the shoulder include flexion (e.g. elevation of the arm in an anterior direction), extension (i.e. return of the arm from a position of flexion to the side of the body), and hyperextension (i.e. elevation of the arm in a posterior direction) frontal plane movements include abduction (i.e. elevation of the arm in a lateral direction) and adduction (i.e. return of the arm from a position of abduction to the side of the body; transverse plane movements include horizontal adduction (i.e. horizontally extended arm is moved medially) and horizontal abduction (i.e. horizontally extended arm is moved laterally); the humerus can also rotate medially (i.e. anterior face of humerus is moved medially) and laterally (i.e. anteiror face of humerus is moved laterally; elevation of the humerus in all planes is accompanied by about 55 degrees of external rotation 193

coracoclavicular joint

the __________________ is a syndesmosis at which the coracoid process of the scapula and the inferior surface of the clavicle are joined by the coracoclavicular ligament; this ligament resists independent upward movement of the clavicle, downward movement of the scapula, and anteroposterior movement of the clavicle or scapula; minimal movement is permitted at this joint; the ___________________ ligaments are frequently ruptured during contact sports, such as football, hockey, and rugby 189

glenohumeral joint

the ___________________ is the articulation between the glenoid fossa of the scapula and the head of the humerus; *although the joint enables a greater total ROM than any other joint in the human body, it is lacking in bony stability;* this primary results from the hemispheric head of the humerus, which has three to four times the amount of surface area compared with the shallow glenoid fossa; because the glenoid fossa is also less curved than the humeral head, the humerus not only rotates, but also moves lineraly across the surface of the glenoid fossa when humeral motion occurs, an action that predisposes the joint to impingement injuries 190

acromioclavicular joint sprains

the ____________________ is weak and easily injured by direct blow, fall on the point of the shoulder (called a shoulder pointer), or force transmitted up the long axis of the humerus during a fall with the humerus in an adducted position; in these cases, the acromion is driven away from the clavicle or vice versa; although often referred to as a separated shoulder, ruptures of the AC and/or costoclavicular ligaments can result in an AC dislocation; therefore, they are more correctly referred to as sprains 197

loose structure

the ______________________ of the shoulder complex enables extreme mobility, but provides little stability; as a result, the shoulder is much more prone to injury than the hip; common injuries include dislocations, clavicular fractures, muscle and tendon strains, rotator cuff tears, acromioclavicular sprains, bursitis, bicipital tendonitis, and impingement syndrome; shoulder injuries commonly occur in activities involving an overhead motion, such as baseball, swimming, tennis, volleyball, and weightlifting; in fact, shoulder pain is the most common musculoskeletal complaint among competitive swimmers, with 40 to 70% reporting a history of shoulder pain; disclocations of the shoulder articulations are not uncommon in contact sports, such as wrestling and football 189

shoulder

the arm articulates with the trunk at the ________________, or pectoral girdle, composed of the scapula and clavicle; the __________________ region has five separate articulations: the sternoclavicular joint, AC joint, coracoclavicualr joint, glenohumaral joint, and scapulothoracic joint; the articulation referred to specifically as the shoulder joint is the glenohumeral joint; the remaining articulations are collectively referred to as the shoulder girdle; the SC and AC joints enhance emotion of the clavicle and scapula, enabling the GH joint to provide a greater range of motion (ROM) 189

acute posterior glenohumeral dislocations signs and symptoms

the arm is carried tightly against the chest and across the front of the trunk in rigid adduction and internal rotation; the anterior shoulder appears flat, the coracoid process is prominent, and a corresponding bulge may be seen posteriorly, if not masked by a heavy deltoid musculature; any attempt to move the arm into external rotation and abduction produces severe pain; because the biceps brachii is unable to function in this position, the individual is unable to supinate the forearm with the shoulder flexed 199

coordination of shoulder movements

the extensive ROM afforded by the shoulder partially results from the loose structure of the GH joint, and partially from the proximity of the other shoulder articulations and the movement capabilities they provide; movement at the shoulder typically involves some rotation at the SC, AC, and GH joints; for example, as the arm is elevated past 30 degrees of abduction, or the first 45 to 60 degrees of flexion, the scapula also rotates, contributing approximately one-third of the total rotational movement of the humerus; this important coordination of scapular and humeral movements, known as scapulohumeral rhythm, enables a much greater ROM at the shoulder than if the scapula were fixed; also contributing to the first 90 degrees of humeral elevation is the elevation of the clavicle through approximately 35 to 45 degrees of motion at the SC joint; the AC joint contributes to overall movement capability as well, with rotation occurring during the first 30 degrees of humeral elevation, and then against as the arm is moved past 135 degrees 193

glenohumeral joint sprain management

the immediate management includes the application of cold to the area; the individual should also be placed in a sling; this injury requires physician referral to ensure accurate assessment and appropriate treatment 198

sternoclavicular joint sprain (anterior) management

the immediate management includes the application of cold to the area; the individual should also be placed in a sling; this injury requires physician referral; if a grade II or grade III injury is suspected, the individual should be referred to an emergency medical facility 197

glenohumeral abduction

the muscles superior to the GH joint produce abduction and include the middle deltoid and supraspinatus; during the contribution of the middle delthoid, from approximately 90 degrees through 180 degrees of abduction, the infraspinatus, subscapularis, and teres minor produce inferiorly directed force to neutralize the superiorly directed dislocating force produced by the middle deltoid; this action serves an important function i npreventing impingement of the supraspinatus and subacromial bursa; the long head of the biceps brachii provides GH stability during abduction 194

glenohumeral flexion

the muscles that cross the GH joint anteriorly are positioned to contribute to flexion; the anterior deltoid and clavicular pectoralis major are the primary shoulder flexors, with assistance provided by the coracobrachialis and short head of the biceps brachii; because the biceps brachii also crosses the elbow joint, it is capable of exerting more force at the shoulder when the elbow is in full extension 193

bursae

the shoulder is surrounded by several ______________, including the subcoracoid, subscapularis, and the most important, the subacromial; the subacromial bursa lies in the subacromial space where it is surrounded by the acromion process of the scapula and the coracoacromial ligament above and the GH joitn below; the ______________ cushions the rotator cuff muscles, particularly the supraspinatus, from the overlying bony acromion and provides the major component of the subacromial guiding mechanism; the bursa can become irritated when repeatedly compressed during overhead arm action 191

glenohumeral joint

the tendons of four muscles, including the supraspinatus, infraspinatus, teres minor, and subscapularis, also joint the joint capulse; these muscles are referred to as the SITS muscles, after the first letter of each muscle's name; they are also known as the rotator cuff muscles because they all act to rotate the humerus and because their tendons merge to form a collagenous cuff around the joint; tension in the rotator cuff muscles helps to hold the head of the humerus against the glenoid fossa, further contributing to joint stability; the joint is most stable in its closed packed position, when the humerus is abducted and laterally rotated 190

glenohumeral extension

when extension is not resisted, the action is caused by gravity; eccentric contraction of the flexor muscles serves as a controlling or breaking mechanism; when resistance by extension is offered, the posterior GH muscles act, including the sternocostal pectoralis, latissismus dorsi, and teres major, with assistance provided by the posterior deltoid and long head of the triceps brachii 194

flexibility exercises for shoulder region

________________ include: posterior capsular stretch; horizontally adduct the arm across the chest while the opposite hand assists the stretch anterior and posterior capsular stretch; hold onto both sides of a doorway with hands behind the back; straighten the arms while leaning forward; repeat with the hand in front while leaning backward inferior capsular stretch; hold the involved arm over the head with the elbow flexed; use the opposite hand to assist in the stretching; add a side stretch medial and lateral rotators; using a towel, bat, or racquet, pull the arm to stretch it into lateral rotation; repeat in medial motion 195

acute posterior glenohumeral dislocations

________________ occur from a fall or a blow to the anterior surface of the shoulder which drives the head of the humerus posteriorly 199

acromioclavicular joint sprains managmeent

________________: the immediate management includes the application of cold to the area; the individual should also be placed in a sling; this injury requires physician referral; *if a type II or higher is suspected, the individual should be referred to an emergency medical facility 198*

strengthening exercises for the shoulder complex

_________________ include: A. shoulder shrugs- elevate the shoulders toward the ears and hold; pull the shoulders back, pinch the ears shoulder blades together, and hold; relax and repeat B. scapular abduction (protraction)- lift the weight directly upward, lifting the posterior shoulder from the table; relax and repeat C. scapular adduction (retraction) perform bent-over rowing while flexing the elbows; when the end of the motion is reached, pinch the shoulder blades together and hold D. bench press or inline press- place the hands shoulder-width apart and push the barbell directly above the shoulder joint; this exercise should be performed with a spotter E. bent arm lateral flies, supine position- keeping the elbows slightly flexed, lift the dumbbells directly over the shoulders; lower the dumbbells until they are parallel to the floor, then repeat; an alternative method is to move the dumbbells in a diagnosal pattern; in the prone position, the exercise strengthens the trapezius F. lateral pull-downs- in a seated position, grasp the handle and pull the bar behind the head; an alternative method is to pull the bar in front of the body G. surgical tubing- secure the tubing; working in diagonal functional patterns similar to those skills experienced in a specific sport/ activity 196

acromioclavicular joint sprains signs and symptoms

__________________: TYPE I injuries have no disruption of the AC or coracoclavicular ligaments; minimal swelling and pain are present over the joint line, and increase in abduciton past 90 degrees; the injury is inherently stable and pain is self-limiting TYPE II injuries result from a more severe blow to the shoulder; the AC ligaments are torn but the coracoclavicular ligament, only minimally sprained, is intact; vertical stability is maintained, but sagittal plane stability is compromised; the clavicle rides above the level of the acromion, and a minor step or gap is present at the joint line; pain increases when the distal clavicle is depressed or move in an anterior-posterior direction, and during passive horziontal adduction TYPE III injuries have complete disruption of the AC and coracoclavicular ligaments, resulting in visible prominence of the distal clavicle; there will be obvious swelling and bruising and, more significantly, depression or drooping of the shoulder girdle TYPE (IV to VI) are caused by more violent forces; extensive mobility and pain in the area may signify tearing of the deltoid and trapezius muscle attachments at the distal clavicle; these rare injuries must be carefully evaluated for associated neurologic injuries 198

sternoclavicular joint sprain (posterior) management

___________________: posterior displacment can become life-threatening; the emergency plan should be activated including summoning of EMS 197

sternoclavicular joint sprain (anterior) signs and symptoms

___________________: FIRST DEGREE injuries are characterized by point tenderness and mild pain over the SC joint, with no visible deformity; characteristics of SECOND DEGREE include: a joint subluxation leading to bruising, swelling, and pain inability to horizontally adduct the arm without considerable pain holding the arm forward and close to the body, supporting it across the chest pain with scapular protraction and retraction can reproduce pain THIRD DEGREE sprains involve a prominent displacement of the sternal end of the clavicle and may involve a fracture; there is a complete rupture of the SC and costoclavicular ligaments; in a third-degree sprain, the movement limitations present in a second-degree sprain are greater and produce more pain; pain is severe when the shoulders are brought together by a lateral force 197

sternoclavicular joint sprain (posterior) signs and symptoms

______________________: the individual has a palpable depression between the sternal end of the clavicle and the manubrium, is unable to perform shoulder protraction, and may have difficulty swallowing and breathing; the individual may also complain of numbness and weakness of the upper extremity secondary to the compression of structures in the thoracic inlet; if the venous vascular vessels are impinged, the patient may have venous congestion or engorgement in the ispilateral arm and a diminished radial pulse 197

prevention of shoulder conditions

acute and chronic injuries to the shoulder complex are common in sports participation; many contact and collision sports do require some protective equipment, but in most cases, *flexibility, physical conditioning, and proper technique* are the primary factors that can reduce the risk of injury to this vulnerable area 194

sternoclavicular joint sprain (posterior)

although rare, posterior, or retrosternal, displacement is more serious because of the potential injury to the esophagus, trachea, internal thoracic artery and vein, and the brachiocephalic and subclavian artery and vein; the *most common* mechanism of injury is a blow to the posterolateral aspect of the shoulder with the arm adducted and flexed, such as a fall on the should displacing the distal clavicle posteriorly; this action may occur during a piling-on injury in football; less commonly, the injury may be caused by a direct blow to the anteromedial end of the clavicle 197

acute anterior glenohumeral dislocations signs and symptoms

an initial dislocation presents with intense pain; tingling and numbness may extend down the arm into the hand; in a first-time anterior dislocation, the injured arm is often held in slight abduction (20 to 30 degree) and external rotation, and is stabilized against the body by the opposite hand; visually, a sharp contour on the affected shoulder, with a prominent acromion process, can be seen when compared with the smooth deltoid outline on the unaffected shoulder; the individual will not allow the arm to be brought against the chest 199

sternoclavicular joint

as the name suggests, the ____________ consists of the articulation of the superior sternum, or manubrium, with the proximal clavicle; the _________________ is surrounded by a joint capsule that is thickened anteriorly and posteriorly by four ligaments, including the interclavicular, costoclavicular, and anterior and posterior SC ligaments the ________________ enables rotation of the clavicle with respect to the sternum; the joint allows motion in the distal clavicle in superior, inferior, anterior, and posterior directions, along with some forward and backward rotation of the clavicle; as such, rotation occurs at the ____________________ during motions, such as shrugging the shoulders, reaching above the head, and in most throwing-type activities; because the first rib is jointed by its cartilage to the manubrium just inferior to the joint, motion of the clavicle in the inferior direction is restricted; the close-packed position for the SC joint occurs with maximimal shoulder elevation 189

glenohumeral adduction

as with extension, adduction in the absence of resistance results from gravatational force, with the abductors controlling the speed of motion; when resistance is present, adduction is accomplished through the action of the muscles positioned on the inferior side of the GH joint, including the latissimus dorsi, teres major, and sternocostal pectoralis; the short head of the biceps and long head of the triceps contribute minor assistance; when the arm is elevated above 90 degrees, the corocaobrachialis and subscapularis also assist 194

scapulothoracic joint

because muscles attaching to the scapula permit its motion with respect to the trunk or thorax, this region is sometimes described as the _____________________; the scapular muscles perform two functions; the first is stabilization of the shoulder region; for example, when a barbell is lifted from the floor, the levator scapula, trapezius, and rhomboids develop tension to support the scapula, and, in turn, the entire shoulder through the AC joint; the second function is to facilitate movements of the upper extremity through appropriate positioning of the GH joint; during an overhand throw, for example, the rhomboids contract to move the entire shoulder posteriorly as the arm and hand move backward during the preparatory phase; as the arm and hand then move forward to execute the throw, tension in the rhomboids is released to permit forward movement of the shoulder, enabling medial rotation of the humerus 191

protective equipment

contact and collision sports, such as football, lacrosse, and ice hockey, require shoulder pads to protect exposed bony protuberances from impact; although shoulder pads do prevent some soft tissue injuries in this region, they do not protect the GH joint from excessive motion 195

proper skill technique

coordinated muscle contractions are necessary for the smooth execution of the throwing motion; any disruption in the sequencing of integrated movements can lead to additional stress on the GH joint and surrounding soft tissue structures; high-speed photography often used to record the mechanics of the throwing motion, can lead to early detection of improper technique; in addition to proper throwing technique, participants in contact and collision sports should be taught the shoulder roll method of falling, rather than falling on an outstretched arm; this technique reduces direct compression of the articular joints and disperses the force over a wider area 196

glenohumeral joint sprain

damage to the ____________________ can occur when the arm is forcefully abducted (e.g. when making an arm takle in football), but more commonly is caused by excessive shoulder external rotation and extension (i.e., arm in the overhead position); when the arm rotates externally, the anterior capsule and GH ligaments are stretched or torn, causing the humeral head to slip out of the glenoid fossa in an anterior-inferior direction; a direct blow or forceful movement that pushes the humerus posteriorly can also result in damage to the joint capsule 198

chronic dislocations management

if the injury does not reduce, the individual should be placed in a sling and swathe, or the arm may be stabilized next to the body with an elastic wrap; ice should be applied to control pain and inflammation; the individual should be referred immediately to a physician for reduction of the injury and further costs 200

glenohumeral joint sprain signs and symptoms

in a FIRST DEGREE injury, the anterior shoulder is particularly painful to palpation and movement, especially when the mechanism of injury is reproduced; active ROM may be slightly limited, but pain does not occur on adduction or internal rotation, such as occurs with a muscular strain; a SECOND DEGREE sprain produces some joint laxity; in addition, pain, swelling, and bruising are usually significant, and ROM particularly abduction is limited a THIRD DEGREE injury is considered a dislocation and is discussed in the next section dislocation 198

acromioclavicular joint sprains type III second degree

injured structures: rupture of AC ligament and coracoclavicular ligament 197

acromioclavicular joint sprains type IV to VI third degree

injured structures: rupture of AC ligament and coracoclavicular ligament, and tearing of deltoid and trapezius fascia 197

acromioclavicular joint sprains type II second degree

injured structures: rupture of AC ligament and partial strain of coracoclavicular ligament 197

acromioclavicular joint sprains type I first degree

injured structures: stretch or partial damage of the AC ligament and capsule

nerves and blood vessels of the shoulder

innervation of the upper extremity arises from the brachial plexus, a combination of nerves branching primarily from the lower four cervical (C5 to C8) and the first thoracic (T1) spinal nerves; the branches from these nerves extend from the neck anteriorly and laterally, passing between the clavicle and first rib; injuries to the clavicle in this region can damage the brachial plexus; the subclavian artery passes beneath the clavicle to become the axillary artery, providing the major blood supply to the shoulder; branches of the axillary artery include the thoracoacromial trunk, lateral thoracic artery, and thoracodorsal artery, as well as the anterior and posterior humeral circumflex arteries that supply the head of the humerus 191

physical conditioning

lack of flexibility can predispose an individual to joint sprains and muscular strains; warm-up exercises should focus on general joint flexibility, and may be performed alone or with a partner using proprioceptive neuromuscular facilitation (PNF) stretching techniques; individuals using the throwing motion in their sport should increase ROM in external rotation, as this has been shown to increase the velocity of the throwing arm and decrease shearing forces on the GH joint 194

lateral and medial rotation of the humerus

lateral rotators of the humerus lie on the posterior aspect of the humerus, including the infraspinatus and teres minor, with assistance provided by the posterior deltoid; muscles on the anterior side of the humerus contribute to medial rotation; these include the subscapularis and teres major, with assistance from the pectoralis major, anterior deltoid, latissimus dorsi, and short head of the biceps 194

sprains to the shoulder complex

liagemntous injuries to the SC joint, AC joint, and GH joint can result from compression, tension, and shearing forces occurring in a single episode, or from repetitive overload; a common method of injury is a fall or direct hit on the lateral aspect of the acromion; the force is first transmitted to the site of impact, then to the AC joint and the clavicle, and finally to the SC joint; failure can occur at any one of these sites; acute sprains are common in hockey, rugby, football, soccer, equestrain sports, and the martial arts 196

acromioclavicular joint sprains classification

like other joint injuries, AC sprains may be classified as first-degree (i.e. mild), second degree (i.e. moderate), or third degree (i.e. severe); however, because of the complexity of the joint, AC sprains are often classified as types I to VI based on the extent of ligamentous damage, degree of instability, and direction in which the clavicle displaces relative to the acromion and coracoid processes 197

acute anterior glenohumeral dislocations

many acute dislocations have an associated fracture or nerve damage; therefore, this injury is considered serious, and necessitates immediate transportation to the nearest facility for reduction 199

acute glenohumeral dislocations management

muscle spasm sets in very quickly following dislocation and makes reduction more difficult; management of a first-time dislocation requires immediate referral to a physician; as such, in some settings, it may be necessary to activate the emergency plan; the injury should be treated as a fracture; the arm should be immobilized in a comfortable position; in order to prevent unnecessary movement of the humerus, a rolled towel or thin pillow can be placed between the thoracic wall and humerus prior to applying a sling; ice should be applied to control hemorrhage and muscle spasm; in evaluating this injury, if possible, the coach should assess both the axillary nerve and artery, because both structures can be damaged in a dislocation; a pulse may be taken on the medial proximal humerus over the brachial artery or on the radial pulse at the wrist; the axillary nerve can be assessed by stroking the skin on the upper lateral arm to assess sensation; deficits with pulse or sensation definitely warrant activation of the emergency plan, including summoning of EMS 199

chronic dislocations signs and symptoms

pain is the major complaint, with crepitation and/or clicking after the arm shifts back into the appropriate position; however, recurrent dislocations may be less painful than an initial dislocation; many individuals voluntarily reduce the injury by positioning the arm in flexion, adduction, and internal rotation 199

chronic dislocations

recurrent dislocations, or "trick shoulders," tend to be anterior dislocations that are intracapsular; the mechanism of injury is the same as acute dislocations; however, as the number of occurrences increases, the forces needed to produce the injury decrease, as do the associated muscle spasm, pain, and swelling; the individual is aware of the shoulder displacing because the arm gives the sensation of going dead, referred to as the *dead arm syndrome;* *activities in which recurrent posterior subluxations are common include the follow-through of a throwing motion or a racquet swing, the ascent phase of a push up or a bench press, the recoil following a block in football, and certain swimming strokes 199*

glenohumeral dislocations

*the GH joint is the most frequently dislocated major joint in the body;* 90% of shoulder dislocations are anterior; posteiror dislocations rank second in occurrence; inferior dislocations are rare and often accompanied by neurovascular injury and fracutre; dislocations can be acute or chronic 199