Osteology and Circulation of the Upper Limb Flashcards
Describe the clavicle
• S-Shaped • Smooth superior surface • Rough inferior surface • Round proximal end • Flat distal end
What are the two ends of the clavicle?
The sternal end (medially) and the acromial end (laterally)
What part of the clavicle is present in the sternoclavicular joint?
The sternal facet.
What features are on the inferior surface of the clavicle?
Impression for costoclavicular ligament
Subclavian groove
Trapezoid line
Conoid tubercle
Describe the sternoclavicular joint
• Very strong ligaments
• Fibrocartilage lined
joint
• Articular disc
Where does the clavicle articulate with the sternum on the sternum?
The clavicular notch
What important ligaments are there in the sternoclavicular joint?
- The anterior and posterior sternoclavicular ligaments between the area of the clavicular notch and the sternal end of the clavicle
- The interclavicular ligament that runs superior to both sternoclavicular ligaments on both sides
- The costoclavicular ligament that runs between the first costal cartilage lateral to the manubrium of the sternum superiorly to the impression for the costoclavicular ligament on the sternal end of the clavicle.
What are some of the important protruding features of the scapula?
The coracoid process and posteriorly the acromion which both lie on the superiolateral part of the scapula
On the acromion may be found the articular surface for the clavicle
On this is the acromioclavicular joint (isn’t anatomy a real hoot?)
What are the important ligaments found in the acromioclavicular joint?
The acromioclavicular ligament can be found between gasp the acromion and the clavicle. This is a planar joint and an intrinsic ligament as they are two flat surfaces meeting without any real change in angle so they have to be reinforced
There is also the coracoclavicular ligament between the coracoid process and the clavicle is actually made of two extrinsic ligaments: the trapezoid and conoid ligaments
Where do the trapezoid and conoid ligaments join to on the clavicle?
The trapezoid line and the conoid tubercle respectively
What are the three angles of the scapula?
Superior - from the supraspinous fossa
Inferior - from the most inferior part of the scapula
Lateral - from the greater scapular notch inferior to the acromion
What are the three fossae of the scapula?
Supraspinous - superior to the spine of the scapula medial to the acromion
Infraspinous - Inferior to the spine of the scapula on the posterior surface
Subscapular - The anterior surface
What are the three borders of the scapula?
Medial - the medial side
Lateral - runs from the most inferior point to the acromion (the lateral side)
Superior - the top
What are some important anatomical features of the scapula?
The glenoid fossa/cavity which articulates with the proximal head of the humerus
The spine of the scapula that runs superiolaterally but mostly laterally on the posterior surface
The suprascapular notch found on the superior border
What are the important features of the suprascapular notch?
It is an osteological feature that is closed over by the upper transverse ligament
This turns the structure into a suprascapular fossa which is important in neuromuscular relationships
Describe the important features of the proximal part of the humerus
- Head
- Two Tubercles
- Two Necks
- Lumps bumps and lines for muscle attachment
Why does the proximal humerus have two necks?
One is the anatomical neck where all the relevant anatomical structures may be found (epiphyseal plates etc)
The other is the surgical neck which is where most proximal humerus fractures occur
Describe the ligaments of the glenohumeral joint
- Joint capsule thickened by ligaments - lax to allow greater movement
- 3 Glenohumeral ligaments
- Superior
- Middle
- Inferior
- Coraco-humeral ligament
- Transverse humeral ligament
- Long head of biceps
What prevents a superior dislocation of the humerus?
The coraco-acromial ligament which is found superior to the humerus
Where are the glenohumeral ligaments found?
Inside the glenohumeral joint capsule
What stops antero-superior dislocations of the humerus?
The coraco-humeral ligament
What holds the long head of the biceps in place?
The transverse humeral ligament that runs between the greater and lesser tuberosity
How does the long head of the biceps help to prevent superior and anterior dislocation of the humerus?
The head passes into the joint capsule and passes over the superior surface of the humeral head where it attaches to the supraglenoid tubercle. Because of this positioning the tone of the long head of the biceps helps to prevent superior and anterior dislocation of the humerus
Where may the coraco-humeral ligament be found on the humerus?
Superior to the synovial membrane of the glenohumeral joint
Where do the superior and middle glenohumeral ligaments travel to on the glenoid fossa?
The supra-glenoid tubercle
What are the important muscles of the glenohumeral joint?
The rotator cuff
What are the important bursae of the glenohumeral joint?
The subacromial(-subdeltoid SASD) bursa The subscapular bursa - an extension of the synovial membrane of the glenohumeral joint
There are also the subcoracoid and coracobrahial bursae amongst others
Describe the main features of the proximal humerus
- Two Tubercles
- Inter-tubercular sulcus
- Medial lateral lips
- Lumps, bumps and lines for muscle attachment
Where are the three main regions that the humerus may fracture at?
The surgical neck
The mid shaft by the spiral groove
The supracondylar region - above the condyles
What nerves must we look out for during fractures of the humerus?
• Mid Shaft • Spiral Groove –Radial nerve • Surgical Neck • Axillary nerve • Supracodylar • Median nerve