Flashcards in Joints of the Upper Limb Deck (43):
What is the general purpose of the clavicle?
the sternoclavicular joint acts as a strut to hold the upper limb away from the chest to afford maximum degree of movement
What are the 3 articulations of the sternoclavicular joint?
Sternal end of clavicle
clavicular notch of manubrium
first costal cartilage
What divides the sternoclavicular joint into 2 synovial cavities?
Interarticular disc (fibrocartilage)
What are the ligaments of the sternoclavicular joint? What is the main support?***
Anterior and posterior sternoclavicular ligaments
In which compartment of the sternoclavicular joint does forward and backward movement of the clavicle take place in? What about elevation and depression?
Medial compartment = forward and backward
Lateral compartment = elevation and depression
What does the costoclavicular ligament firmly hold together?
Firms hols the medial end of clavicle to the first costal cartilage and first rib
What does the acromioclavicular joint articulate with?
acromion process of scapula
acromial extremity of clavicle
What is the main support ligament of the acromioclavicular joint?
What does the coracoclavicular ligament connect?
Connects the coracoid process of scapula to undersurface of clavicle
What is the coracoclavicular ligament responsible for?
Suspending the weight of scapula and upper limb from the clavicle
What happens in an acromioclavicular dislocation?
Acromion process is thrust beneath lateral end of clavicle
clavicle is elevated
Shoulder falls away from clavicle because of weight of upper limb
What does the shoulder joint (glenohumeral joint) articulate with?
Articulates with the head of the humerus and the glenoid cavity of the scapula
What deepens the glenoid cavity?
A rim of fibrocartilage called the glenoid labrum
What are the 2 apertures in the articular capsule of the glenohumeral joint?
1. Between the tubercles of the humerus (for passage of tendon of long head of biceps)
2. Opening for subscapular bursa (continuation of synovial cavity of the joint)
What are the 4 ligaments of the shoulder joint?
1. Glenohumeral ligaments (strength capsule anteriorly)
2. Transverse humeral ligament (hold down the synovial sheath and tendon of long head of biceps)
3. Coracohumeral ligament (strengthens capsule superiorly)
4. Coracoacromial ligament (connects coracoid process to acromion process)
What makes up the coracoacromial arch? What is its purpose?
coracoid process -- coracoacromial ligament -- acromion process
Prevents superior displacement of head of humerus
What are the 4 rotator cuff tendons?
Rotator cuff tendons are the principal support of shoulder joint
1. Supraspinatous tendon (superior support)
2. Infraspinatous tendon (posterior support)
3. Teres minor tendon (posterior support)
4 Subscapularis tendon (anterior support)
What is the only anatomical direction that the capsule is not supported by from the rotator cuff tendons?
rotator cuff tendons do not support the capsule of this joint inferiorly
Definition of bursae of shoulder joint.
Synovial sacs located where tendons rub against bone, ligaments, other tendons, or skin, so as to prevent friction
What are the 2 principal bursae of the shoulder joint?
Subscapular bursa (between tendon of subscapularis muscle and scapula)
Subacromial bursa (between deltoid muscle and supraspinatous tendon)
Which of the 2 principal bursae communicate with the capsule of the shoulder joint, and which doesn't?
Subscapular bursa communicates with the capsule of shoulder joint
Subacromial bursa does not communicate with capsule of shoulder joint
What muscles control flexion of the shoulder joint?
What muscles control extension of the shoulder joint?
What muscles control abduction of the shoulder joint?
What muscles control adduction of the shoulder joint?
What muscles control the lateral rotation of the shoulder joint?
What muscles control the medial rotation of the shoulder joint?
What is the weak part of the capsule of the shoulder joint, why, and what happens when there is displacement here? What nerve is at risk of being damaged?
Weak part of the capsule of shoulder joint is the inferior part
No rotator cuff tendons inferiorly
Leads to anterior-inferior dislocation
May damage the axillary nerve
What results in a posterior dislocation?
Subglenoid displacement of the humeral head into the quadrangular space
could cause damage to axillary nerve with paralysis of deltoid muscle and loss of skin sensation over lower half of deltoid
What happens if there is swelling of the supraspinatous muscle or excessive fluid within the subacromial bursae?
May cause impingement when arm is abducted
Causes degeneration of the tendon (supraspinatous tendinopathy)
Extreme pain during abduction
What is the most common issue with the shoulder joint in the elderly?
Rupture of the supraspinatous tendon
What does the elbow joint articulate with?
-between the trochlea and trochlear notch of ulna
-between the capitulum and the head of radius
What are the principal planes of movement of the elbow joint?
Only 1 principal plane of movement:
Flexion and extension
What are the 2 supporting ligaments of the elbow joint?
Radial collateral (lateral epicondyle to anular ligament of radius)
Ulnar collateral (medial epicondyle to coronoid and olecranon process of ulna)
What are the articulations of the proximal radioulnar joint?
- between head of radius and radial notch of ulna
- at the synovial pivot joint which allows for supination and pronation
What is the supporting ligament of the proximal radioulnar joint, and what is it attached to?
The annular ligament
Attached to the margins of the radial notch
Not directly attached to radius
What happens with a 'pulled elbow'?
Radial head moves distally partially out of annular ligament
What are the articulations of the distal radioulnar joint?
- between the head of ulna and the ulnar notch of the radius
- synovial pivot joint which allows for supination and pronation
What separates the ulna from the wrist joint?**
The articular disc of the distal radioulnar joint
**Ulna does NOT contribute to the wrist joint
What makes up the wrist joint?
Made up of the distal radius and articular disc (scaphoid, lunate, and triquetral carpal bones)
What type of joint is the wrist joint?
An ellipsoid type of wrist joint
What are the movements of the wrist joint? Which is greater?
Flexion (~80 degrees) > Extension (~45 degrees)
Adduction > Abduction