2 Objectives1. Name, locate, & describe the structure & ligamentous reinforcements of the joints. 2. Name & demonstrate movements possible. 3. Name & locate muscles & muscle groups, and name their primary actions. 4. Analyze the fundamental movements with respect to joint & muscle actions. 5. Describe common injuries.
3 Acromioclavicular (AC) Joint Articulation of acromion & distal end of clavicle.Acromioclavicular ligament strengthens joint superiorly.Aponeurosis of trapezius & deltoid strengthen joint posteriorly.Coracoclavicular ligament further stabilizes joint.Fig 5.1
4 Sternoclavicular (SC) Joint Fig 5.2Proximal clavicle articulates with sternum and cartilage of 1st rib.Capsule thickened by anterior & posterior sternoclavicular ligaments.The only bony connection between the humerus and axial skeleton.Permits limited motion of the clavicle.Partially responsible for movements of the scapula.Clavicular movements at the SC joint:elevation & depression,protraction & retraction,forward & backward rotation.
5 Movements of the Shoulder Girdle Fig 5.3 a & bAbduction (Protraction)Adduction (Retraction)ElevationDepression
6 Movements of the Shoulder Girdle Fig 5.3 c & dUpward rotationDownward rotationAnterior tiltPosterior tilt
7 MUSCLES OF THE SHOULDER GIRDLE Location:AnteriorPectoralis minor, Serratus anterior, SubclaviusPosteriorLevator scapulae, Rhomboids, Trapezius
8 Pectoralis Minor Function: Movements of scapula: downward rotation, anterior tilt, depression.Lifting effect on ribs in forced inspiration and posture.Fig 5.4
9 Serratus Anterior Function: Abduct (protract) scapula. Fig 5.4Function:Abduct (protract) scapula.With trapezius, upward rotation of scapula.Active in reaching and pushing.
10 Subclavius Function: Protect and stabilize sternoclavicular joint. Fig 5.4Function:Protect and stabilize sternoclavicular joint.Depress scapula.
11 Levator Scapulae Function: Elevation and downward rotation of scapula. Fig 5.5
12 Rhomboids, Major and Minor Function:Downward rotation, adduction (retraction), & elevation of scapula.Works with trapezius for maintenance of good posture.Fig 5.5
14 GLENOHUMERAL (Shoulder) JOINT Structure Fig 5.7Articulation of spherical head of humerus with small, shallow glenoid fossa of scapula.Fig 5.8Glenoid labrum deepens the fossa and cushions impact of humeral head in forceful movements.
16 Muscular Reinforcements Superior: supraspinatus & long head of biceps.Inferior: long head of triceps.Anterior: subscapularis, pectoralis major, & teres major.Posterior: infraspinatus & teres minor.
17 Movements of the Shoulder Joint Internal rotationExternal rotationFlexion / ExtensionHyperextensionCircumductionAbduction / AdductionHorizontalDiagonalInternal / External Rotation
18 MUSCLE OF THE SHOULDER JOINT Location:Anterior: Pectoralis major, coracobrachialis, subscapularis, biceps brachii.Posterior: Infraspinatus, teres minor.Superior: Deltoid, supraspinatus.Inferior: Latissimus dorsi, teres major, long head of triceps brachii.
19 Pectoralis MajorFig 5.11Function: Clavicular portion – flexion, horizontal adduction, and internal rotation of humerus. Sternal portion – downward & forward movements of arm, & internal rotation with adduction.
20 Coracobrachialis Function: Horizontal adduction Fig 5.12Function:Horizontal adductionActs like a guy wire to stabilize the shoulder joint.
21 Biceps Brachii Function: Flexion at the elbow & supination of forearm. Fig 5.12Function:Flexion at the elbow & supination of forearm.Horizontal adduction at shoulder.Short head sometimes active in adduction & internal rotation.
22 DeltoidFig 5.14Function:Anterior – all forward movements & internal rotation of humerus.Middle – abductionPowerful abductor of humerus.Posterior – extension, hyperextension, horizontal extension, adduction.
23 Subscapularis Function: Internal rotation of humerus as part of the rotator cuff.Contributes to stability of shoulder joint.Fig 5.13a
24 Supraspinatus Function: Acts with deltoid in abduction of the arm. Active in flexion & horizontal extension.Contributes to stability of shoulder joint.Part of the rotator cuff.Fig 5.13b
25 Infraspinatus and Teres Minor Function:External rotation as part of the rotator cuff.With subscapularis depresses head of humerus.Contributes to stability of shoulder joint.Fig 5.13b
27 Teres MajorFunction:Internal rotation, extension, & adduction of the arm.Fig 5.15
28 Triceps Brachii Function: Long head assists in adduction, extension, and hyperextension of the humerus.Fig 5.15
29 and the shoulder (glenohumeral) joint. JOINT AND MUSCULAR ANALYSIS OF THE FUNDAMENTAL MOVEMENTS OF THE ARM ON THE TRUNKMovements of the arm on the trunk involve the cooperative action of theshoulder girdleAcromioclavicular jointsSternoclavicular jointsand the shoulder (glenohumeral) joint.
30 Movements in the Frontal Plane Fig 5.16Shoulder Joint: AbductionDeltoid & supraspinausShoulder Girdle: Upward rotation of scapulaSerratus anterior; trapezius II & IVFig 5.17Shoulder Joint: AdductionLatissimus dorsi, teres major, pectoralis major (sternal), & post. deltoid.Shoulder Girdle: reduction of upward rotationRhomboids & pectoralis minor.
31 Movements in the Sagittal Plane Shoulder Joint: FlexionAnterior deltoid & pectoralis major (clavicular).Shoulder Girdle: Upward rotation of scapulaSerratus anterior & trapezius II & IV.Fig 5.18
32 Movements in the Sagittal Plane Fig 5.19Fig 5.20Shoulder Joint: ExtensionPectoralis major (sternal), teres major, latissimus dorsi, post. deltoid.Shoulder Girdle: Reduction of upward rotation of scapulaRelaxation of agonistsAgainst resistance - trapezius IV, rhomboids, pect. minor.Shoulder Joint: HyperextensionTeres major, latissimus dorsi, post. Deltoid.Shoulder Girdle: Anterior tilt of scapulaPectoralis minor.
33 Movements in the Horizontal Plane Shoulder Joint: External RotationInfraspinatus & teres minorShoulder Girdle: Adduction of scapulaRhomboids & trapezius III.Fig 5.22a
34 Movements in the Horizontal Plane Fig 5.22bShoulder Joint: Internal RotationSubscapularis, teres major, latissimus dorsi, ant. deltoid, pectoralis major.Shoulder Girdle: Abduction of scapulaSerratus anterior & pectoralis minor.Shoulder Joint: Horizontal AdductionPectoralis major, ant. deltoid, & coracobrachialis.Shoulder Girdle: Abduction of scapulaSerratus anterior & pectoralis minorShoulder Joint: Horizontal AbductionPost. deltoid, post middle deltoid, infraspinatus, teres minor, long head of biceps.Shoulder Girdle: Adduction of scapulaRhomboids & trapezius III.
35 Diagonal MovementsDiagonal forward-downward and slightly inward movement of the arm.Fig 5.23Fig 5.10
36 COMMON INJURIES OF THE SHOULDER REGION: Acromioclavicular Sprain AC joint forced beyond normal ROM.Downward blow to outer end of shoulder.Fall on outstretched hand.Damage consists of tearing or severe stretching of AC ligaments.
37 COMMON INJURIES OF THE SHOULDER REGION: Fracture of The Clavicle Clavicle fractures have causes similar to AC sprain:Downward blow to outer end of shoulder.Fall on outstretched hand.May indicate injury by supporting injured arm.Head may be tilted toward injured side with face turned to opposite side.
38 COMMON INJURIES OF THE SHOULDER REGION: Dislocation of the Shoulder May be forward, downward, or posterior.Most likely when arm is forcefully abducted and laterally rotated.May occur by a blow to top of shoulder .Head of humerus is forced out of the glenoid fossa.Arm held out from side in a position of slight abduction and lateral rotation.Loss of normal rounded contour of deltoid muscle.
39 COMMON INJURIES OF THE SHOULDER REGION: Rotator Cuff Tears Supraspinatus (supraspinatus tendon) most often injured.Nature of injury depends on arm kinematics.Caused by overuse, falls, or violent, fast arm motion.
40 COMMON INJURIES OF THE SHOULDER REGION: Shoulder Impingement Soft tissue superior to humeral head pressed against acromion process.Due to overuse, inflammation, trapped bursa, degeneration with aging.Will cause pain and inflammation in shoulder.