Lecture 11 - Shoulder girdle Flashcards
What are the functions of the upper limb?
Reaching, grasping
Lifting, carrying
Throwing, hitting
Delicate manipulations (mainly fingers of the hand)
What bones comprise the shoulder girdle?
Scapula and clavicle
Describe the morphology of the scapula
The scapula is a flat triangular shaped bone. It has 3 borders, and 3 angles.
On the anterior surface there is a concavity known as the subscapular fossa, and on the posterior side there are two fossas divided by the spine of the scapula, the Supraspinatus fossa, and the infraspinatus fossa.
The spine of the scapula ends as the acromion, and the process projecting anteriorly is the coracoid process
The medial and lateral border, spine, acromion and Coracoid process act as sites for attachements for muscles
What two things does the clavicle join together?
The clavicle acts as a strut, joing the scapula to the sternum
Label this
How can the scapula move?
The scapula is a mobile bone that can slide relative to the rib cage; in conjunction with the clavicle, sternoclavicular and Acromioclavicular joints
What is the clavicle attached to on the medial side?
It is connected to the manubrium, and the first rib
What are the six movements of the shoulder girdle?
Elevation, depression
Protraction, retraction
Medial and lateral rotation
What are some other words used for flexion and extension which mean the same thing?
Anteversion = flexion
Retroversion = extension
What limits movement of the shoulder joint?
Ligaments and muscles of the shoulder joint (mainly stabilising muscles)
What does the sternoclavicular joint connect, and what kind of joint is it?
Connects the clavicle to sternum and 1st costal cartilage
It is a ball and socket joint, with there being a fibrocartilaginous articular disc within the joint (acts as a damper)
Label this
What two bones does the costoclavicular ligament connect?
The first rib and its costal cartialge inferiorly to the clavicle
Where is the Acromioclavicular joint? And briefly describe what kind of joint it is
It’s a small synovial (plane joint) between the acromion and lateral end of clavicle
It has a pad of fibrocartilage that projects into the joint
It is also supported by the coracoclavicular ligament (trapezoid and conoid ligaments)
What is the proper name of the shoulder joint?
Glenohumeral joint
Label this
Why is there such a large range of movement at the shoulder joint?
The joint surface of the scapula is small relative to the joint surface of the humerus
What group of muscles stabilises the shoulder joint?
Rotator cuff muscles
What are the rotaror cuff muscles?
Subscapularis
Supraspinatus
Infraspinatus
Teres minor
Each muscle has a tendon, which blends together to form a ‘cuff’
Label this
What is the main extrinsic muscle of the shoulder joint?
Deltoid muscle
It consists for 3 parts, and it’s key function is abduction
Which nerve innervates the deltoid muscle?
Axiallary nerve
What are the intrinsic muscles of the shoulder joint?
Supraspinatus muscle
Infraspinatus muscle
Teres muscles
What nerve innervates the supraspinatus muscle?
Suprascapular nerve
What nerve innervates the infraspinatus muscle?
Suprascapular nerve
Which nerve(s) innervate the Teres muscles?
Subscapular nerve, Axiallary nerve
What muscle is this, and which nerve inneravtes it?
What are the extrinsic muscles of the shoulder on the anterior side of the trunk?
Pectoralis major and pectoralis minor
The pectoralis major is innervated by what nerves?
And what innervates the pectoralis minor?
Pectoralis major is innervated by the medial and lateral pectoral nerve
The pectoralis minor is innervated by the lateral pectoral nerve
What are the extrinsic muscles of the shoulder on the posterior side of the trunk?
Trapezius
Latissimus dorsi
Levator scapulae and rhomboids
What nerves innervate the following:
Trapezius
Latissimus dorsi
Levator scapulae and rhomboids
Trapezius is innervated by the accesory nerve (11th cranial nerve)
Latissimus dorsi is innervated by the thoracodorsal nerve
Levator scapulae and rhomboids is innervated by the dorsal scapular nerve
What is the extrinsic muscle located on medial border of the scapula, and which nerve is it innervated by?
Serratus anterior
Long thoracic nerve
Which extrinsic muscle of the should joint has two bellies and allows for supination of the elbow joint, and what nerve is it innervated by?
Biceps brachii
Musculocutaneous nerve
What are the four muscles of the rotator cuff?
And why is it called a rotator “cuff”?
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Each muscle has a tendon which come togethet to form a cuff
What is this ligament called?
Coracoacromial ligament
