Functional and clinical anatomy of the shoulder Flashcards
Week 1
Name the 3 basic bones of the shoulder
Clavicle
Scapula
Humerus
Name a joint between the clavicle and scapula
Acromioclavicular joint (between the acromium of the scapula and clavicle).
Generally, what type of muscles attach to the coracoid?
Flexors and adductors of the limb
Generally, what type of muscles attach to the scapula?
Extenders and abductors of the limb
What type of joint is the acromioclavicular joint?
Plane types synovial joint
What does the proximal head of humerus articulate with to form the shoulder joint?
Glenoid fossa of the scapula
Name the joint between the humerus and the scapula
Glenohumeral joint
Name the 2 tubercules of the proximal humerus
Greater and lesser tubercles - form attachments for muscles
What runs in the intertubercular groove between the greater and lesser tubercles of the humerus?
Tendon of the long head of the biceps brachii muscle.
What is the difference between the anatomical neck and surgical neck oft he humerus?
Anatomical neck = where bone grows from
Surgical neck = narrowest point, most likely to fracture
What nerve runs around the surgical neck of the humerus?
Axillary nerve
Explain how a fracture in the neck of the humerus can cause ‘Sargent’s stripes parasthesia’
Fracture - tear of the axillary nerve - loss of sensation laterally over the shoulder - paralysis of deltoid muscle
Name 3 muscles which originate/attach at the corachoid process of the scapula
- Pectoralis minor
- Coracobrachialis
- Short head of biceps brachii
Name 4 fossas of the scapula
- Glenoid fossa
- Subscapular fossa
- Supraspinous fossa
- Infraspinous fossa
Where does the long head of the biceps brachii attach?
Supraglenoid tubercle
Where does the long head of the triceps brachii attach?
Infraglenoid tubercle
Why is the shoulder joint a relatively unstable joint?
Glenoid cavity is substantially smaller than the head of the humerus - allows a good degree of mobility around the joint.
What is used to stabilise the shoulder joint?
Tendons, ligaments and muscles
Ligaments between the scapula/clavicle.
- Acromioclavicular ligament
- Coracoacromio ligament
- Coracoclavicular ligaments (trapezoid and conoid)
Ligaments between clavicle/sternum
- Sternoclavicular ligaments
- Costoclavicular ligaments
- Interclavicular ligaments
Ligaments involving the humerus
- Coracohumeral ligament
- Glenohuemral ligament
- Transverse humeral ligament
A fibrocartilaginous structure rim attached around the margin of the glenoid cavity which acts to deepen the socket
The labrum glenoidale
How many muscles are there in the rotator cuff?
4
Muscles of the rotator cuff
- Supraspinatous
- Infraspinatous
- Subscapularis
- Teres minor
Why is it easy to dislocate shoulder inferiorly?
No muscles pass underneath.
Superficial extrinsic muscles
- Trapezius
- Latissimus Dorsii
Deep extrinsic muscles
- Levator Scapulae
- Rhomboid major
- Rhomboid minor
Shoulder movements:
Flexion, extension, abduction, adduction, medial rotation, lateral rotation
What is a bursa?
synovial fluid-filled sac which acts as a cushion between tendons and other joint structures.
Pain in first part of arc =
Problem with glenohumeral joint
Pain in last part of arc =
Problem with acromioclavicular joint
If you had supraspinatous tendonitis, which part of the arc would be painful?
Middle part