Conference 4: Shoulder & Arm Flashcards
1
Clavicle
2
Scapula
3
humerus
1
Coracoid process
2
Acromion process
3
Glenoid fossa
4
head of humerus
5
greater tubercle of humerus
What is the diagnosis?
Anterior dislocation of the head of the humerus
What provides normal shoulder contour under deltoid just distal to the acromion?
Greater tubercle
The longitudinal axis of humerus normally points toward what part of the shoulder?
Acromion
Why does the right arm appear lengthened with the right elbow lower than the other elbow?
Dislocated humeral head is now mostly located inferior to the glenoid fossa
What are the normal anatomic factors that make the shoulder joint vulnerable to dislocation?
- Poor bony fit of round humeral head and shallow socket of the glenoid fossa
- Relatively loose joint capsule
What structures help maintain contact of the humeral head with the glenoid fossa?
Rotator cuff muscles
Identify the Rotator Cuff Muscles and their functions.
- supraspinatus: lateral abduction
- infraspinatus: external rotation
- teres minor: external rotation
- subscapularis: internal rotation
Where is there no muscular reinforcement of the joint capsule?
Inferiorly
What anatomic relationships makes the axillary nerve vulnerable to injury in shoulder dislocation?
Because the axillary nerve courses anterior and inferior to the glenohumeral joint, it will be placed on traction by an anteroinferior dislocation.
What is the lesion visible in this x-ray?
Midshaft fracture of humerus
1
Head of humerus
2
glenoid fossa
3
joint capsule
4
supraspinatus
5
Clavicle
6
Acromion
7
subacromial subdeltoid bursa
8
Greater tubercle
9
deltoid
10
articular cartilage
