Bones & Joints Of The Shoulder Girdle

Question 1

Discuss the pectoral/shoulder girdle

Answer 1

-Consists of the clavicle and scapula
-Connects the upper extremity to thorax via sternoclavicular joint
-No posterior attachment to thorax
-Relies on muscular stability for support
-Allows extensive ROM

Question 2

Name the articulating surfaces and classification of the glenohumeral joint

Answer 2

-Articulating surfaces: glenoid fossa, head of humerus
-Classification: multiaxial ball & socket synovial joint

Question 3

Discuss the movements at the glenohumeral joint

Answer 3

-Flexion and extension
-Abduction and adduction
-Horizontal abduction and adduction
-Internal and external rotation

Question 4

Discuss the capsule of the glenohumeral joint

Answer 4

-Envelopes joint
-Attaches from circumference of glenoid fossa to neck of humerus
-Full adduction: inferior aspect loose, superior aspect taut
-Full abduction: inferior aspect taut, superior aspect loose
-Tendons of supraspinatus, infraspinatus, teres minor, and subscapularis blend with capsule

Question 5

Discuss the labrum of the glenohumeral joint

Answer 5

-Redundant capsular fold made of fibrocartilage
-Lines the glenoid
-Deepens the glenoid fossa to increase congruency between apposing bones
-Intracapsular

Question 6

Name the ligaments of the glenohumeral joint

Answer 6

-Glenohumeral ligament
-Coracohumeral ligament
-Transverse humeral ligament
-Coracoacromial ligament

Question 7

Discuss the glenohumeral ligament and its limits

Answer 7

-Comprised of 3 bands: superior, middle, inferior
-Forms a “Z” shape
-Considered partially capsular (shares some fibres with joint capsule
-Attaches from glenoid fossa to humerus
-Limits: horizontal abduction, external/lateral rotation

Question 8

Discuss the coracohumeral ligament and its limits

Answer 8

-Comprised of 2 bands: superior and inferior
-Extracapsular
-Attaches from coracoid process to humerus
-Limits: external rotation, supports the dependant arm against gravity

Question 9

Discuss the transverse humeral ligament and its limits

Answer 9

-Arches over the bicipital groove/sulcus
-Extracapsular
-Attaches across bicipital sulcus
-Limits: lateral displacement long head biceps

Question 10

Discuss the coracoacromial ligament and its limits

Answer 10

-One bend that arches over glenohumeral joint
-Extracapsular
-Attaches from corocoid process to acromial process
-Limits: superior displacement of head of humerus, contributes to coracoacromial arch

Question 11

Define bursae

Answer 11

-Fluid-filled sacs containing synovial fluid, located adjacent to tendons that cross joints
-Acts to decrease friction between adjacent structures during movement

Question 12

Name the articulating surfaces and classification of the acromioclavicular joint

Answer 12

-Articulating surfaces: acromial facet of clavicle (lateral clavicle) and medial acromion
-Classification: non-axial, plane synovial joint

Question 13

Discuss superior and inferior scapular rotation and its plane and axis at the AC joint

Answer 13

-Superior rotation: glenoid faces superior; accompanies humeral abduction and flexion
-Inferior rotation: gelnoid faces inferior; accompanies humeral adduction and extension
-Frontal plane and anteroposterior axis

Question 14

Discuss protraction and retraction of the scapula at the AC joint and its plane and axis

Answer 14

-Protraction: involves some medial scapular rotation
-Retraction: involves some lateral scapular rotation
-Transverse plane (roughly) and vertical axis (roughly

Question 15

Discuss upward tip/tilting of the AC joint and its plane and axis

Answer 15

-Scapula rotates so inferior angle moves posteriorly, and superior border moves anteriorly
-Allows scapula to appose thoracic wall during elevation
-Sagital plane and medial-lateral axis

Question 16

Describe the capsule and disc of the AC joint

Answer 16

-Capsule: relatively weak; cannot maintain joint integrity independently
-Fibrocartilagenous disc: may remain as a vestigial remnant. Often absent by age 40

Question 17

Name the ligaments of the AC joint

Answer 17

-Acromioclavicular ligament
-Superior transverse scapular ligament
-Coracoclavicular ligament

Question 18

Discuss the acromioclavicular ligament and its limits

Answer 18

-Maintains joint congruency via superior and inferior bands
-Limits: one bone overriding another, joint distraction

Question 19

Discuss the superior transverse scapular ligament and its limits

Answer 19

-Arches over the suprascapular notch
-Suprascapular nerve passes inferior to ligament; suprascapular artery and vein pass superior to ligament
-No limit (does not cross joint)

Question 20

Discuss the coracoclavicular ligament

Answer 20

-Composed of two separate bands consisting of the conoid ligament and trapezoid ligament

Question 21

Discuss the conoid ligament and trapezoid ligament

Answer 21

-Conoid ligament: attaches posteromedial to the trapezoid ligament
-Trapezoid ligament: attaches anterolateral to conoid
-Both act to transfer force from scapula to clavicle than sternoclavicular joint during a FOOSH

Question 22

Name the articulating surfaces and classification of the SC joint

Answer 22

-Articulating surfaces: sternal facet of clavicle, superolateral manubrium (clavicular facet), superior aspect of costal cartilage of rib 1
-Classification: non-axial, double plane synovial joint (two joint spaces)

Question 23

Name the movements of the SC joint and its planes and axis’

Answer 23

-Clavicular elevation and depression: frontal plane and ant-post axis
-Clavicular protraction and retraction: transverse plane and vertical axis
-Rotation: mechanical axis of clavicle

Question 24

Describe the capsule and disc of the SC joint

Answer 24

-Capsule: relatively lax and thin above and below joint
-Fibrocartilagenous disc: attaches to clavicle superiorly, junction of manubrium, and first costal cartilage inferiorly
-Divides joint space into medial and lateral spaces
-Involved in some motion at SC joint; acts as shock absorber

Question 25

Describe the SC ligament and its limits

Answer 25

-Anterior and posterior bands reinforce the capsule
-Limits: anterior and posterior displacement of the clavicle

Question 26

Describe the costoclavicular ligament and its limits

Answer 26

-Attaches from first rib superolaterally to clavicle
-Serves as axis for clavicular protraction+retraction and elevation+depression
-Limits: clavicular elavation, protraction+retraction, and shoulder girdle movements during last 90 degrees of GH abduction and flexion

Question 27

Describe the interclavicular ligament and its limits

Answer 27

-Spans the sternal notch attaching medial clavicles
-Limits: superior+inferior clavicular displacement

Question 28

Discuss the scapulothoracic (ST) joint

Answer 28

-Not true joint, describes relationship between anterior scapula and posterior thoracic wall
-Motion entirely dependant on function and movement of the AC and SC joints