Anatomy of the Shoulder ATHT 205 Chad Dufrene Spring 2016

Objectives Knowledge of Anatomy Knowledge of Pathology Knowledge of HOPS associated with pathology Rehabilitation

Bony Anatomy Shoulder complex Sternum Clavicle Scapula Humerus

Sternum Manubrium Attachment site for clavicle Jugular notch Clavicular notch

Clavicle Short bone between the sternum and scapula Elevates and rotates for kinematic efficiency Anterior convex bend at proximal 2/3. Flattened concave bend at distal 1/3. The distal 1/3 is the most common site for fractures.

Scapula Glenoid fossa Subscapular fossa Vertebral border Inferior angle Superior angle Scapular spine Infraspinous fossa Supraspinous fossa Acromion process Coracoid process

Humerus Humeral head Anatomical neck Bicipital groove Greater tuberosity Lesser tuberosity Surgical neck Deltoid tuberosity

Shoulder Joints Sternoclavicular (SC) Acromioclavicular (AC) Scapulothoracic Glenohumeral

Sternoclavicular (SC) Articulation of the proximal clavicle, manubrium, and first costal cartilage Gliding synovial joint Allows 3 degrees of motion. Aids in elevation, depression, protraction, retraction, internal rotation, and external rotation Poor bony stability Sternoclavicular disk -shock absorber

Sternoclavicular (SC) cont. Strong ligamentous support Difficult to dislocate. Ligaments Posterior sternoclavicular Anterior sternoclavicular Interclavicular costoclavicular

Acromioclavicular (AC) Articulation of the distal clavicle and the acromion process. Plane synovial joint Allows 3 degrees of motion Aids in internal rotation, external rotation, upward rotation, downward rotation, anterior scapular tipping, and posterior scapular tipping Synovial disk present in approximately first 20 years of life

Acromioclavicular (AC) cont. Coracoacromial ligament Acromioclavicular ligament Restricts superior clavicular movement Coracoclavicular ligament Trapezoid ligament Conoid ligament Restricts horizontal movement of clavicle Restricts rotation of the scapula

Scapulothoracic Not a true anatomical joint No fibrous, cartilaginous, or synovial articulation Movement only in response to AC and SC joint movement Limited mobility in AC or SC affect mobility of scapulothoracic joint

Glenohumeral (GH) Articulation of the humeral head and the glenoid fossa Ball and socket joint 3 degress of motion Aids in flexion, extension, abduction, adduction, internal rotation, and external rotation Horizontal adduction, horizonal abduction, and circumduction

Glenohumeral (GH) cont. Glenoid labrum Thick fibrous tissue Deepens the GH articulation Joint capsule Glenohumeral ligaments Superior, middle, and inferior Inferior pouch Foramen of Weitbrecht (weak spot)

Glenohumeral Ligaments External Rotation Ligament Stressed External Rotation in 0 degrees of abduction Superior GH Ligament Coracohumeral Ligament External Rotation in 45 degrees of abduction Middle GH Ligament Anterior Band of Inferior GH Ligament External Rotation in 90 degrees abduction Posterior Band of Inferior GH Ligament

Glenohumeral Ligaments Movement Ligament Stressed Internal rotation at 90 degrees abduction Posterior Band of Inferior GH Ligament Inferior Displacement in 0 degrees abduction Superior GH Ligament Coracohumeral Ligament Inferior displacement in 90 degrees abduction Inferior GH Ligament

Glenohumeral (GH) cont. Coracohumeral ligament Joins superior capsule and supraspinatus tendon to the greater tuberosity Limits inferior translation of humeral head Limits flexion and extension Limits external rotation

Glenohumeral (GH) cont. Coracoacromial ligament Stretches from the inferior acromion process to the posterior portion of the coracoid process. Forms the coracoacromial arch Protects the superior humeral head, rotator cuff tendons, and bursae. Prevents superior and anterior GH dislocations.

Muscles of the Shoulder Complex Chad Dufrene ATHT 469

Supraspinatus Origin- Supraspinous fossa Insertion- Medial aspect of the greater tuberosity and GH joint capsule Action- Abduction, External rotation, and Humeral head stabilization. Innervation- Suprascapular (C4,C5,C6)

Infraspinatus Origin- Infraspinous fossa of the scapula Insertion- Lateral portion of greater tuberosity of the humerus, GH capsule Action- External rotation, Horizontal abduction, Humeral head stabilization Innervation- Suprascapular (C5,C6)

Clinical Examination of Shoulder Injuries ATHT 469 Dufrene

Disclaimer A thorough evaluation is key due to the interrelationship between the shoulder complex and the cervical spine, thoracic spine, torso, abdomen, and elbow. The shoulder complex is a common site for visceral organ referred pain and orthopedic radiating pain.

History (Past Conditions) “Have you injured your shoulder before?” Past medical history Pre-participation physicals are important. There may be a relationship between the current condition and a past condition.

History (Present Conditions) Location “Where does it hurt?” “Point with one finger where it hurts the most.” “What type of pain?” “Is the pain traveling or radiating?” “Is there numbness or tingling?”

History Onset “When did the pain start?” “Did the pain worsen over time?” “Is the pain constant?” “What activities worsen pain?” “Did you hear or feel a pop or snap?” Acute? Chronic? Insidious onset?

History Mechanism of Injury This is the investigation of “how” the injury happened. What inside or outside forces caused this injury? Was there an impact? Was it a non-contact injury? Was it a chronic injury caused by repetitive force?

History Symptoms Pain? Performance Deficiency? Loss of ROM? Joint Instability? Radiating Pain? Numbness? Tingling?

History Conclusion The history of an acute traumatic injury should focus on the mechanism of injury. The history-taking process expands for cases involving an insidious onset.

Observation Functional Assessment Apprehension to movement? Bracing to alleviate or reduce symptoms? Example (flexing the trunk while abducting for supraspinatus pathology) Observe the scapula during movement

Observation Shoulder level Thoracic Outlet Syndrome AC joints, clavicles, and SC joints should align bilaterally Dominant shoulder may appear slightly lower than nondominant one. Resting position? Decreased muscular tone? Depressed shoulder complexes can lead to thoracic outlet syndrome Rounded shoulders indicate tight pectoralis musculature. Scoliosis?

Observation Head Position Normally assumes an upright position A head that is rotated or bent to the side may indicate muscle spasm, cervical nerve root compression, or stretching of the cervical nerves.

Observation Arm Position Is arm locked in a fixed position? GH dislocation Is arm splinted? Traumatic injury Is arm hanging? Brachial plexus injury

Observation Clavicles Clavicular Fx Compare clavicles bilaterally Look for gross deformities SC or AC joint sprains usually present gross deformity at the articulation Past trauma? Clavicular fx present a clear deformity of the shaft Usually the distal 1/3 Patient holds arm next to body and rotates head to opposite side

Observation Deltoid Symmetry Dominant arm is usually more hypertrophied compared to nondominant arm. Severe atrophy may reflect C5 and C6 pathology. Flattening of deltoid area is an indication of a dislocated GH joint.

Observation Biceps Brachii Biceps Tendon Rupture A long head of the biceps tendon rupture will present a unilateral bulge within the muscle. Distal tendon can rupture also.

Observation Acromion Process AC Sprain Step Deformity? AC sprain The clavicle rides above the acromion process.

Observation Scapular Position Scapular Winging Vertebral borders should be equidistant from the spinous processes In anatomical position, the scapula is in full contact with the thorax Unilateral protraction? Unilateral retraction? Unilateral tilting? Scapular winging? Sprengel’s deformity Congenital undescended scapula

Observation Muscle Development Ecchymosis Look for symmetry Spasm? Deformity? Discoloration? Ecchymosis Muscle wasting?

Clinical Evaluation of the Shoulder Part 2 Chad Dufrene

Palpation The bony structures are palpated prior to soft tissue structures to rule out fractures, dislocations, and gross joint injury. If gross deformity is found, the limb should be examined for neurologic and vascular compromise. Immobilize the shoulder and refer to a physician.

Palpation (pgs.634-636) Anterior Bony Structures Posterior Bony Structures Jugular notch SC joint Clavicular shaft Acromion process AC joint Coracoid process Humeral head Greater tuberosity Lesser tuberosity Bicipital groove Humeral shaft Scapular spine Superior angle Inferior angle Spinous processes from C1-T12

Palpation (pgs. 634-636) Anterior Muscular Structures Posterior Muscular Structures Pectoralis major Pectoralis minor Coracobrachialis Deltoids Biceps brachii Rotator cuff muscles Teres major Rhomboids Levator scapulae Trapezius Latissimus dorsi Posterior deltoid Triceps brachii

Goniometry Glenohumeral Flexion GH isolaged: 0-120 degrees Shoulder complex: 0-180 degrees. Patient Supine Fulcrum: lateral to the acromion process Stationary arm: parallel to the thorax Movement arm: midline of lateral humerus Isolate GH flexion by stabilizing the axillary border of the scapula Note measurement when scapula begins to move

Goniometry Glenohumeral Extension 0-60 degrees Patient prone Fulcrum: Aligned lateral to the acromion process Stationary arm: parallel to the thorax Movement arm: over midline of lateral humerus Stabilize scapula on its posterior surface to isolate GH extension

Goniometry Abduction GH isolated: 0-120 degrees Shoulder complex: 0-180 degrees Patient Supine Fulcrum: Anterior to acromion process Stationary arm: parallel to midline of torso Movement arm: midline of anterior humerus To isolate GH, stabilize the scapula at its axillary border. Note the measurement when scapula begins to move.

Goniometry Internal Rotation 0-90 degrees Patient supine with shoulder and elbow 90/90 Fulcrum: lateral to olecranon process Stationary arm: perpendicular to floor or parallel to tabletop Movement arm: long axis of ulna Stabilize scapula to isolate GH joint. When scapula moves, notate the measurement.

Goniometry External Rotation 0-100 degrees Patient Prone with shoulders 90/90 Fulcrum: lateral to olecranon process Stationary arm: perpendicular to floor or parallel to tabletop Movement arm: over long axis of ulna Stabilize the scapula until it starts to move. That’s when you notate the measurement.

Goniometry Horizontal Abduction 0-90 degrees Patient seated with arm abducted to 90 degrees, elbow flexed, and forearm pronated. Fulcrum: Superior acromioclavicular joint Stationary arm: perpendicular to trunk Movement arm: parallel to longitudinal axis of humerus Isolate GH motion during horizontal adduction, stabilize scapula at axillary border.

Goniometry Horizonatl Adduction 0-50 degrees Patient seated with arm abducted to 90 degrees, elbow flexed, and forearm pronated. Fulcrum: Superior AC Stationary arm: perpendicular to trunk Movement arm: parallel to longitudinal axis of the humerus Isolate GH motion during horizontal adduction. Stabilize scapula at axillary border.

Muscle Review (minor movements in italics) Scapular Elevation Scapular Depression Levator scapulae Trapezius (upper portion) Rhomboid major Rhomboid minor Serratus anterior (upper portion) Trapezius (lower portion) Pectoralis major (clavicular portion) Serratus anterior (lower portion)

Muscle Review Scapular Protraction Scapular Retraction Serratus anterior Rhomboid major Rhomboid minor Trapezius (middle) Trapezius (lower)

Muscle Review Scapular Upward Rotation Scapular Downward Rotation Serratus anterior Trapezius (upper) Rhomboid major Rhomboid minor Levator scapulae Trapezius (lower)

Muscle Review Shoulder Flexion Shoulder Extension Biceps brachii Coracobrachialis Deltoid (anterior) Pectoralis major (clavicular head) Deltoid (posterior) Latissimus dorsi Teres major Triceps brachii (long head)

Muscle Review Adduction Abduction Coracobrachialis Latissimus dorsi Pectoralis major Teres major Triceps brachii Supraspinatus (1st 30 degrees) Deltoid (middle) Biceps brachii Deltoid (anterior) Deltoid (posterior)

Muscle Review Horizontal Adduction Horizontal Abduction Deltoid (anterior) Pectoralis major Infraspinatus Teres Minor Deltoid (posterior)

Muscle Review Internal Rotation External Rotation Subscapularis Teres major Pectoralis major Latissimus dorsi Deltoid (anterior) Infraspinatus Teres Minor Supraspinatus Deltoid (posterior)

Clinical Examination of the Shoulder Dufrene Part 3

Manual Muscle Testing Following active range of motion (AROM), manual muscle testing is used to detect pain or weakness associated with more specific muscle involvement. Remember to be aware of the athlete’s reaction to your manual muscle testing (MMT). The content in the textbook between pg. 647-652 is a helpful tool in understanding manual muscle testing.

Dermatome/Myotome C4 Dermatome: Superior shoulder, clavicle area. Myotome: Shoulder shrug (trapezius, levator scapulae) Reflex: N/A

Dermatome/Myotome C5 Dermatome: Deltoid, lateral upper arm Myotome: Shoulder abduction (deltoid), elbow flexion (biceps) Reflex: Biceps

Dermatome/Myotome C6 Dermatome: Lateral forearm, radial side of hand, thumb, and index finger Myotome: Elbow flexion (biceps, supinator), wrist extension Reflex: Brachioradialis

Dermatome/Myotome C7 Dermatome: Posterior lateral arm and forearm, middle finger Myotome: Elbow extension (triceps), wrist flexion Reflex: Triceps

Dermatome/Myotome C8 Dermatome: Medial forearm, ulnar border of hand, ring and little finger. Myotome: Ulnar deviation, thumb extension, finger flexion and abduction. Reflex: N/A

Dermatome/Myotome T1 Dermatome: Medial elbow, arm Myotome: Finger abduction Reflex: N/A

Nerve Branches Musculocutaneous (C5-C7) Dermatome: Lateral forearm Myotome: Elbow flexion Reflex: N/A

Nerve Branches Median (C5-C7, C8-T1) Dermatome: Distal radial aspect, index finger Myotome: Thumb pinch, opposition, and abduction Reflex: N/A

Nerve Branches Ulnar (C8,T1, some C7) Dermatome: Distal ulnar side of 5th finger Myotome: Abduction, 5th finger Reflex: N/A

Nerve Branches Axillary (C5,C6) Dermatome: Lateral arm, deltoid Myotome: Shoulder abduction Reflex: N/A

Nerve Branches Radial (C5-C8, T1) Dermatome: Dorsal web space, between thumb and index fingers Myotome: Wrist extension, thumb extension Reflex: N/A

Shoulder Pathology and Injury

Sternoclavicular Injury Most commonly caused by falling on an outstreched arm (FOOSH) which causes a longitudinal force. Anterior dislocations are more common than posterior dislocations. Posterior dislocations are a medical emergency due to threat to subclavian artery, subclavian vein, trachea, and esophagus.

Sternoclavicular Joint Injury HOPS Be aware of ligamentous and/or SC disk damage. Pseudo-dislocation: The clavicle’s medial epiphysis does not completely fuse until approximately age 25. A fracture at this area can mimic an SC dislocation. H: FOOSH O: Displacement P: Pain, crepitus S: Joint play testing. -Grade 1: pain -Grade 2: hypermobility -Grade 3: hypermobility

Sternoclavicular Injury Treatment A closed reduction is usually performed to fix a dislocation. Unstable dislocations are usually repaired surgically. Immobilization Control of inflammation Initiate ROM exercises Strengthen surrounding musculature.

Shoulder Lecture Part 4 Dufrene

Acromioclavicular Joint Anterior and posterior stability of the AC joint is maintained by the AC ligament. Superior stability is maintained by the conoid and trapezoid segments of the coracoclavicular ligament.

AC Joint Pathology Mechanism of Injury Landing on a forward-flexed outstreched arm or the point of the elbow, which drives the scapula posterior to the clavicle. A blow to the superior acromion process, which drives the scapula inferior to the clavicle. A force that drives the clavicle away from the scapula when the scapula is fixated. Acute overuse with repetitive stress.