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 nerveWhat are the main features of the distal humerus?
Anteriorly there are the coronoid and lateral to that the radial fossa, which are both superior to the trochlea and capitulum respectively
The trochlea and capitulum are parts of the condyle of humerus
Posteriorly the trochlea can be seen to continue to the posterior aspect of the distal humerus to allow for articulation with the ulna, and superior to the trochlea on the posterior surface may be found a thumb size fossa called the olecranon fossa
What are the main important features on the proximal ulna?
The trochlear notch that forms a “hook” shape to articulate with the trochlear
The top of the hook at the most proximal part of the ulna is the olecranon, which articulates with the olecranon fossa on the humerus
The most distal prominence of the trochlear notch is the coronoid process that articulates with the coronoid fossa of the humerus
Distal to the trochlear notch on the lateral surface is the radial notch where the ulna articulates with the radius at their proximal ends
There is also a tuberosity for the attachment of something and a supinator crest for the attachment of the supinator muscle
What are the important features of the proximal radius?
It has an almost perfectly circular head with an impression that articulates with the capitulum on the humerus
A radial tuberosity can be found distal to the tapered neck of the radius slightly on the medial side of the radius
What two joints make up the elbow joint?
– Humreo-ulnar joint
– Humero-radial joint
What kind of joint is the elbow joint?
complex or compound joint
What links the elbow joint to the proximal radio-ulnar joint?
They are actually the same joint, as they share a common synovial and joint capsule
Describe the elbow soft tissues
There are fat pads in the radial and coronoid fossae
A synovial membrane shared with the elbow joint(s) and the proximal radio-ulnar joint
Holding the proximal head of the radius to the ulna is the anular ligament of radius which originates on the ulna and wraps over the sacciform recess of synovial membrane found on the proximal head of the radius and returns to the other side of the ulna
As the elbow is a hinge joint, there are collateral ligaments: the radial and ulnar collateral ligaments(made of three parts that Fraser doesn’t care abt so I won’t either)
What ligament of the elbow is soley involved in the radio-ulnar joint?
the anular ligament of radius which originates on the ulna and wraps over the sacciform recess of synovial membrane found on the proximal head of the radius and returns to the other side of the ulna, encapsulating it and allowing for the rotational movement of the radius
What may occur as a result of the movement allowed by the anular ligament of radius?
“Pulled elbow”
- Fix it by supinating and extending antebrachium
What bursae are present on the elbow?
The olecranon bursae, including: • Deep Intratendinous bursa • Superficial Subcutaneous bursa
What fracture is very common in the antebrachium?
Colle’s fracture - at the wrist, makes the hand and 4arm appear like the shape of a fork
In what population are Colle’s fractures most common
old ladies that fall and break said fall with their hands and Fraser Chisholms med school friend
What occurs in a Colle’s fracture?
The distal fragment of the radius overrides the rest of the bone
What occurs in pronation?
The Pronator trees pulls the radius over the ulna medially, rotating the hand to face palm down
What occurs in supination?
The supinator muscle pulls the radius over the ulna laterally, rotating the hand to face palm up (anatomical position)
How many bones in the hand?
27
How many bones in the phalanges of the hand?
14 long bones
How many bones in the metacarpals?
5 long bones - one for each digit
How many bones in the carpals?
8 short bones with cool names
What carpal bones may be found in the proximal row?
Scaphoid, Lunate, Triquetrum and pisiform although pisiform has no role in the carporadial joint
What carpal bones may be found in the distal row
Trapezium, Trapezoid, Capitate and Hammate
What kind of joint is the carporadial joint?
condyloid synovial joint
What joints are the carpal bones involved in?
The carporadial joint, The carpometacarpal (carpal-metacarpal) joints The intercarpal joints The mid carpal joint The pisoiotriquetral joint
Name the carpal bones
Some lovers try positions they can't handle (right to left proximal -> distal) = Scaphoid Lunate Triquetrum Pisiform -- Trapezium Trapezoid Capitate Hammate
Describe the radoiocarpal joint
- Ulna does not take part
- Separated by fibrocartilage disc
- Palmar and dorsal radio-carpal ligaments
- Palmer ulno-carpal ligament
- Radial and ulnar collateral ligaments
What type of joints are the carpal-metacarpal joints?
– 1st- saddle joint
– 2-5 condyloid joints
Where is the midcarpal joint?
– between rows
Where is the joint capsule int he carpal joints?
Joint capsule continuous with Carpal-metacarpal
Describe the carpal tunnel
- Carpal bones form a carpal arch
- Flexor retinaculum forms a roof
- Connects both medially and laterally
- Has contents - to be discussed later
Where are the connections of the carpal tunnel?
- Medially:
- Hook of Hamate
- Pisiform
- Laterally:
- Tubercle of Trapezium
- Scaphoid
What are the joints of the hand and what types of joint are they?
- 1st Carpal-metacarpal
- Saddle joint
- Separate from other CMC joints
- Metacarpal-phalangeal
- Condylar joint
- Collateral and palmar ligaments
- Interphalangeal
- Hinge joints
- Collateral and palmar ligaments
Where do the intermetacarpal joints come into the joints of the hand?
They are continuous with CMC joints – palmar, dorsal and interosseous ligaments
Describe the possible movement of digits along each joint
IP joints
• Flexion/extension
MCP joint
• Flexion/extension
• Adduction/Abduction
• Middle finger axisWhere do the subclavian arteries start?
at Brachiocephalic trunk (right) and Aortic arch (Left)
Where do the subclavian arteries finish?
at Lateral border of 1st Rib – becomes The Axillary artery
What are two relevant branches of the subclavian arteries?
Dorsal Scapular and Suprascapular,
take a wild guess where they go
Where does the axillary artery start and finish?
lateral border of 1st Rib to inferior border of Teres major
• becomes the brachial artery
What muscle does the axillary artery pass posteriorly that defines its structure?
Pectoralis minor
What is the structure of the axillary artery?
- Split to 3 parts
- 1st before Pec. minor
- 2nd behind Pec minor
- 3rd after Pec. minor
How many branches does each part of the axillary artery have?
- Part 1 has 1 branch
- Part 2 has 2 branches
- Part 3 has 3 branches
What is the branch that comes off the 1st part of the axillary artery?
The superior thoracic artery
- before pec. minor the artery is still v much on the thorax = thoracic artery, and is kinda high up I guess, = superior thoracic artery
What branches come off the 2nd part of the axillary artery?
The thoraco-acromial artery
The lateral thoracic artery
- so the 2nd part is in the shoulder, one of the most important bits of bone in the shoulder is the acromion but it also supplies the thorax cause its a dumb looking shape, so thoraco-acromial artery
- this artery supplies the thorax still, but we’re now at the side of the body instead of the top, so its lateral thoracic artery
What branches come off the 3rd part of the axillary artery?
The subscapular artery
The Anterior circumflex humeral artery
Posterior circumflex humeral artery
- we’re now leaving the shoulder, but the back of the shoulder still needs some blood for those sweet rows you’re definitely gonna do on that rowing machine you paid £50 for, so we have the subscapular artery to match your substellar attempt at fitness
- Next are the ant. and post. circumflex humeral arteries, as we leave the shoulder, we gotta give it a hug goodbye from both sides. And what do we call a hug in medicine? A circumflex, which is funny so imma go with humeral circumflex
What prevents you from losing circulation in your arm when your shoulder is at a funny angle?
Scapular anastamosis
What vessels make up the scapular anastamosis?
The subscapular artery, the dorsal scapular artery and the circumflex scapular branch of the subscapular artery
