17-01-22 - Osteology and Circulation of the Upper Limb Flashcards
Learning outcomes
- Identify all of the bones and bony landmarks of the upper limb
- Describe the soft tissue features of joints of the upper limb (Capsule and ligaments)
- Describe the arterial supply and venous drainage of the upper limb; including pulses and anastomoses
- Describe the lymphatic drainage of the upper limb and the lymph nodes of the axilla
What shape is the clavicle?
Describe the texture of the clavicle.
Describe the shape of the ends of the clavicle.
What 2 things does the clavicle articulate with?
What are the names of these joints?
What is unique about 1 of these articulations?
Why is the clavicle commonly fractured?
How does it tend to fracture?
- The clavicle is s-shaped
- It has a smooth superior surface, and rough inferior surface
- The clavicle has a round sternal end (proximal), and a flat acromial end (distal)
- The clavicle articulates with the manubrium of the sternum at the sternoclavicular joint and acromion of the scapula at the acromioclavicular joint
- The clavicle is the only bony articulation between the upper limb and the axial skeleton
- The clavicle is commonly fractured, as when falling on the upper limb, the force is transmitted to the clavicle
- It tends to fracture in the middle, with the proximal sternal end up and the distal acromial end down
Where does the manubrium attach to the clavicle in the sternoclavicular joint?
Why are more structures needed to support this joint?
What are these structures?
What type of joint does this make the sternoclavicular joint?
What are 3 intrinsic ligaments used?
What is the strongest ligament used?
Where does it attach?
Why is fracture of the clavicle unlikely to occur at the proximal sternal end of the clavicle?
Where is it most likely to occur?
What is a step deformity?
- The manubrium attaches to the clavicle at the clavicular notch of the round proximal end of the clavicle
- More structures are needed to support this joint, as it is shallow
- Very strong ligaments and a fibrocartilaginous interarticular disc is used for force shock absorption and keeping the joint together
- This makes the joint an atypical synovial joint
• 3 ligaments intrinsic ligaments used in this joint:
1) Anterior sternoclavicular ligament
2) Posterior sternoclavicular joint
3) Interclavicular joint
- The strongest ligament used is the extrinsic costoclavicular ligament, which attaches to the first rib and the first costal cartilage
- Fracture is very unlikely to occur at the proximal sternal end of the clavicle due to the presence of all these ligaments and the fibrocartilaginous disk
- This means it will normally disarticulate at the distal acromial end where the clavicle attaches to the acromion of the scapula
- A step deformity is a visibly raised point of the shoulder where the collar bone (clavicle) and shoulder blade (scapula) has been separated due to a ligament tear
On this diagram identify: • The coracoid process • Th articular surface for clavicle (small flat part of acromion process • The acromion processes • Spine of Scapula
What type of joint is acromioclavicular joint?
What are the 2 ligaments that support the acromioclavicular joint?
How are they formed?
Where do they attach?
What does this cause on the clavicle?
Where do the sub-ligaments of one of these ligaments attach to the clavicle?
What can cause acromioclavicular dislocation?
How can this be identified on an x-ray?
- The acromioclavicular joint is a planar synovial joint
- The acromioclavicular ligament is formed by the thickening of the joint capsule, and attaches the acromion to the distal acromial end of the clavicle
- The coracoclavicular ligament is formed by the trapezoid and conoid ligament and attaches the inferior surface of the clavicle to the coracoid process of the scapula, which causes some roughening and features on this surface of the clavicle.
- The trapezoid ligament attaches to the conoid tubercle (small, rounded part of bone) of the clavicle
- The trapezoid ligament attaches to the trapezoid line on the inferior surface of the clavicle
- Acromioclavicular dislocation can be caused by someone falling on their elbow or shoulder, resulting in the clavicle being displaced upwards
- This can be seen on an x-ray by a dup forming between the clavicle and acromion
Identify on the scapula: • The 3 angles • The 3 fossae (rounded part of bone) • The 3 borders • What 3 ways can the scapula be orientated?
1) The scapula has a concave anterior surface
2) The spine of the scapula is posterior (faces backwards)
3) The acromion and coracoid process are all on the lateral side
Where is the glenoid fossa of the scapula located?
Where is the suprascapular notch located on the scapula?
How does it exist in the body?
What kind of relationships does it have?
Where is the spine of the scapula located?
- The glenoid fossa/cavity is located on the lateral border of the scapula
- The suprascapular notch exists above the scapula
- In the body, it is closed over by the upper transverse scapular ligament, which turns it into the suprascapular foramen, which has neurovascular relationships
What is the head of the proximal humerus like?
How many tubercles does the proximal humerus have?
What exists between them? Why does the proximal humerus have 2 heads?
Where are these heads found?
What are lumps, bumps and lines used for on the proximal humerus?
- The proximal head of the humerus has a smooth surface for articulation
- The proximal humerus has two tubercles, in between which lies the intertubercular sulcus/groove
- The proximal humerus has an anatomical and surgical neck
- The anatomical neck is typically found where the epiphysis joins to the diaphysis, where we found the epiphyseal growth plate in the metaphysis
- Inferior to the tubercles, we have a narrowing of the diaphysis, which is called the surgical neck, because this is where the humerus is more likely to fracture
- The lumps, bumps and lines are for muscular attachment on the humerus
What bones articulate in the glenohumeral joint?
What kind of joint Is the glenohumeral joint?
Why is the glenohumeral joint unstable?
How does this affect movement?
How is the joint capsule thickened?
What are the 6 ligaments involved in stabilising the glenohumeral joint?
Where do they each attack?
What is another muscle that supports the joint?
- In the glenohumeral joint, the proximal head of the humerus articulates with the glenoid cavity/fossa of the scapula
- The glenohumeral joint is a ball and socket joint
- It is an unstable joint as the glenoid fossa is shallow, meaning it is not a deep socket
- This allows for a wide range of movement
- The joint capsule is thickened by ligaments, making it lax
• Ligaments involved in stabilising the glenohumeral joint:
1) Superior glenohumeral ligament – attaches to supra-glenoid tubercle, which exists as a bump at the top of the glenoid fossa
2) Middle glenohumeral ligament - attaches to supra-glenoid tubercle, which exists as a bump at the top of the glenoid fossa
3) Inferior glenohumeral ligament – more broad attachments to the glenoid fossa
4) Coraco-acromial ligament – Sits at the top of the humeral, and prevents dislocation superiorly
5) Coraco-humeral ligament - comes from coracoid process to the humeral head
6) Transverse humeral ligament – Runs between 2 sides of the intertubercular sulcus
• The long head of biceps brachii passes up into the joint capsule and attaches over the top of the humeral head, which helps to prevent humeral dislocation
What are the most important muscles in the stability of the glenohumeral joint?
How do they attach to the joint?
What is the most important factor in the stability of the glenohumeral joint?
What are bursae?
What are they needed for in this joint?
What are the 4 bursae in the glenohumeral joint?
- The most important muscles in the stability of the glenohumeral joint are the muscles of the rotator cuff
- They are 4 muscles that attach as a ring around the humeral head
- Tone of the muscles in the rotator cuff are the most important factors of the glenohumeral joint
- A bursa is a closed, fluid filled sac that is needed to prevent rubbing across bones and ligaments
• 4 bursae of the glenohumeral joint:
1) Subacromial (Subdeltoid – SASD) – prevents tendon from rubbing on the acromion process. Also responsible for extending the deltoid
2) Subscapular – Out pouch of synovial membrane of glenohumeral joint. Anterior to the joint capsule. Prevents muscle from rubbing. Beneath muscle called subscapularis
3) Subcoracoid
4) Coracobrachial
How many tubercles does the humerus have?
What exists between these tubercles?
What is another feature that leads to this?
What are the lumps, bumps, and lines on the humerus for?
How does the humerus attach to the deltoid muscle?
What are 3 places where the humerus can fracture?
What are the neural structures associated with these areas?
- The humerus has two tubercles
- There is an intertubercular sulcus between these 2 tubercles
- There are medial and lateral lips to the intertubercular sulcus, and a floor to which muscles will attach
- Lumps, bumps, and lines on the humerus are for muscle attachment
- There isa bulge on the lateral aspect of the humerus, known as the deltoid tuberosity, which attaches to the deltoid muscle
• 3 areas of potential humeral fracture:
1) Mid shaft – spiral groove which the radial nerve runs through
2) Surgical neck – axillary nerve
3) Supracondylar (near the bottom) – median nerve
What is the condyle of the distal humerus?
What is it used for?
What are the 2 parts of the condyle of the distal humerus?
What are the shapes of these parts?
What exists above the condyle anteriorly?
What are epicondyles?
What are the 2 epicondyles of the distal humerus?
What are they used for?
What is located above the condyle posteriorly?
What is it used for?
What does the humerus articulate with?
- The condyle is the smooth parts anteriorly and posteriorly of the distal humerus which forms an articulation with another bone
- The condyle of the distal humerus can be broken down into the capitulum and trochlea
- The capitulum is round like a head, while the trochlea looks like a pulley
- Above the condyle anteriorly there are 2 recesses called the radial fossa the coronoid fossa
- Epicondyles are rough projections on the condyle which are used as site for muscular attachment
- The lateral epicondyle is used for extensors
- The medial epicondyle is used for flexors
- Above the condyle of the distal humerus posteriorly, there is the olecranon fossa, which provides space for the olecranon of the ulna during extension of the forearm
- The humerus articulates with the radius and ulna
How does the proximal ulna articulate with the humerus?
How does the proximal ulna articulate with the radius?
What are the 2 processes found on the proximal ulna?
Where are they found?
What are they used for?
- The proximal ulna articulates with the humerus through the trochlear notch at the top of the ulna, which articulates with the trochlear notch of the humerus
- The proximal ulna articulates with the radius via the radial notch on the lateral aspect, which articulates with the radial head
- On the proximal ulna, the coronoid process exists anteriorly, and the olecranon is posterior
- These processes provide muscle attachments for supinator muscle
What is the shape of the proximal radius?
Where is the neck of the proximal radius located?
What is located distal to the neck?
- The proximal radius has a smooth rounded head
- The neck is located beneath the head
- Distal to the neck of the proximal radius, there is a bump called the radial tuberosity (rounded prominence on a bone, usually for the attachment of muscles or ligaments)
What 3 bones does the elbow joint consist of?
What is the purpose of the olecranon fossa?
What 2 joints make up the hinge joint of the elbow?
What joint shares a joint and synovial capsule with eh elbow joint?
- The elbow joint consists of the humerus, radius and ulna
- Above the condyle of the distal humerus posteriorly, there is the olecranon fossa, which provides space for the olecranon of the ulna during extension of the forearm
- The hinge joint of the elbow is made from the humero-ulnar joint and the humero-radial joint
- The proximal-radio ulnar joint shares a joint and synovial capsule with the hinge joint of the elbow
How strong are the dimensions of the elbow capsule?
Why is it like this?
Where does the annular ligament attach?
What is the purpose of the annular ligament?
What causes a pulled elbow?
What group of people is pulled elbow more common in?
Why is this?
What are the bursae in the elbow joint named after?
What are the 2 types of olecranon bursae?
- The elbow capsule is lax (not strict) anteriorly and posteriorly for flexion and extension
- The elbow capsule is strong medially and laterally due to collateral ligaments, such as the radial and ulnar collateral ligament
- The annular ligament goes around the head of the radius
- It attaches the radius to the ulna, and allows the radius to rotate within it
- Pulled elbow is caused by the pulling the radius out of the annular ligament
- A pulled elbow is more common in children, because the annular ligament is laxer, and the head of the radius is smaller
- The bursae in the elbow joint are named after the muscles to which they relate
• There are 2 types of olecranon bursae:
1) Deep intratendinous bursa
2) Superficial subcutaneous bursa
How do the ends of the radius and ulna relate to each other?
What do the medial borders of these bones have?
Which sides of the radius and ulna face each other in the forearm?
What is the styloid process of the radius and ulna?
Where is it located on each bone?
What is It used for?
What is it prone to?
How is the distal radius commonly fractured?
How does a colles fracture form?
- The radius is small proximally and large distally
- The ulna is large proximally and small distally
- The medial borders of the radius and ulna have a sharp interosseus border, with a rounder lateral border (sharp on the inside, round on the outside)
- Medial side of the radius and the lateral side of the ulna face each other in the forearm
- The radius and ulna have a styloid process located at the distal end of each bone, which is a sticky out part of bone associated with different ligaments
- The styloid processes have an articulation at the distal end of each bone
- The styloid process is prone to fracture
- The distal radius is commonly fractured by falling onto an outstretched hand
- A colles fracture is a distal radial fracture that is displaced up the way
What type of joint is the middle radio-ulnar joint?
What joint is located distally to the radius and ulna?
What is the wrist joint also known as?
What is not part of the wrist joint?
What ligaments exist between the distal radius and ulna?
Where are they strong and weak?
What joints does the synovial membrane of the wrist encompass?
What exists in these areas to aid movement?
What is it made from?
Where does it run from?
What are the 2 radio-ulnar movements?
Describe these movements
• The middle radio-ulnar joint is a fibrous syndesmosis joint formed by an interosseus membrane
• Distally to the radius and ulna there is the distal radio-ulnar joint
• The wrist joint is also known as the radial-carpel joint, and exists between the radius and the carpal bones of the hand
• The ulna is not part of the wrist joint, as a fibrous disc exists in between the ulna and carpel bones
• There are anterior and posterior radio-ulnar ligaments, which are weak anteriorly and posteriorly (large range of movement), and laterally strong (slim range of movement)
• The synovial membrane of the wrist encompasses the distal radio-ulnar joint and the radial-carpel joint
• There is a sacciform recess, which is a thin extension of the articular capsule of the proximal radio-ulnar joint that runs between the distal radius and distal ulna that aids in movement.
• It runs under the annular ligament of the radius
• The 2 radio-ulnar movements are supination and pronation
• Supination is how the radius and ulna exist in the anatomical position
• During pronation, the radius rotates around the distal ulna at the distal radio-ulnar joint
How many bones are there in the hand?
What are the 3 different types of bones?
How many are there of each?
What kind of bones are each type?
What are the 4 bones in the proximal row of carpal bones?
What is unique about 1 of these bones?
What are the 4 bones in the distal row of carpal bones?
- There are 27 bones in the hand
- 3 different types of bones in the hand:
1) 14 phalanges – long bones – 3 bones in each finger, except thumb with 2
2) 5 metacarpals – long bones – 1 for each digit
3) 8 carpals – short bones
• 4 bones in the proximal row of carpal bones:
1) S – Scaphoid – looks like a boat, has a hollowness
2) L - Lunate – crescent/moon shaped
3) T - Triquetrum – articulates with lunate, hammate, and another bone
4) (P – Pisiform) – small p shaped sesamoid bone – only articulates with triquetrum.
• The pisiform doesn’t take part in the radio-carpel joint or the mid-carpel joint between the proximal and distal rows
• 4 bones in the distal row of carpal bones:
1) Tz – Trapezium – base of thumb
2) Td – Trapezoid – by trapeziums side
3) C – Capitate – great big head
4) H – Hammate – has a bi hook – hook of hamate
What bones does not take part in the radio-carpal (wrist) joint?
What is this joint separated by?
What are the 5 ligaments associated with the radio-carpal joint?
How do these ligaments affect the movement of the joint?
- The ulna does not take part in the radio-carpal joint
- The radio-carpal joint is separated by a fibrocartilage disc
• 5 ligaments associated with radio-carpal joint:
1) Palmar radio-carpal ligament
2) Dorsal radio-carpal ligament
3) Palmar ulno-carpal ligament
4) Radial collateral ligament
5) Ulnar collateral ligament
• These ligaments cause the joint to be laxer anteriorly and posteriorly, and more limiting from side to side
What are the 4 different types of carpal joints?
Where is there a continuous joint capsule?
Why might this be problematic?
What is there supporting these joints?
• 4 different types of carpal joints:
1) Inter-carpal joints
• Planar sliding synovial joints
• Sliding movement
2) Mid-carpal joint
• Between the proximal and distal rows of carpal bones
• Mid-carpal joint is mostly for abduction and extension
• Adduction/flexion mostly from radio-carpal joint
3) Pisiotriquetral joint
• Pisiform attaches to triquetrum
4) Carpal-metacarpal joints
• 1st saddle joint at the base of thumb
• 2-5 condyloid joints
• Extension/flexion and abduction/adduction
- There is a joint capsule of carpal joints continuous with carpal-metacarpal joints, except of the thumb
- This continuous joint capsule may lead to the spread of infection
- There are lots of small unnamed ligaments supporting the joints
What is the carpal tunnel?
How is the carpal tunnel formed?
What does the carpal tunnel connect between medially?
What does the carpal tunnel connect between laterally?
How does carpal tunnel syndrome arise?
- The carpal tunnel is a small inexpandable space
- The carpal is formed by the carpal bones forming an arch, and the flexor retinaculum (fibrous sheet) forming a roof over the arch
- The carpal tunnel connects between the hook of the hamate and pisiform medially
- The carpal tunnel connects between the tubercle of the trapezium and the scaphoid laterally
- Carpal tunnel syndrome is caused by tendons in the carpal tunnel getting inflamed and compressing nerves
What are the 4 types of joints in the hands?
• 4 types of joints in the hand:
1) 1st carpal-metacarpal joint
• Saddle joint
• Separate from the other carpal-metacarpal joints
2) Metacarpal-phalangeal joints
• Distally at the heads of metacarpals
• Condylar joints
• Collateral and palmar ligaments connecting them together
• Flexion/extension and abduction/adduction
3) Interphalangeal joints
• Proximal and distal joints in fingers
• 1 joint in the thumb
• Collateral and palmar ligaments in between the phalanges
4) Intermetacarpal joints
• Continuous with carpal-metacarpal joints
• Palmar, dorsal and interosseus ligaments
Why are movements in the hand important?
What movements are interphalangeal joints for?
What movements are metacarpal-pharyngeal joints responsible for?
What are the movements in reference to?
What is abduction and adduction in reference to?
What is the only thing the middle finger can do?
What does gripping require?
What are all the muscles in the middle finger?
Describe flexion/extension of the thumb.
Describe abduction/adduction of the thumb
- Movements in the hand are important as muscles in the forearm and hand are named for the action they can produce
- Interphalangeal (IP) joints are responsible for flexion/extension
- Metacarpal-pharyngeal (MCP) joints are responsible for flexion/extension and adduction/abduction
- These movements are in reference to a middle finger axis, not the body
- Abduction is movement away from the middle finger
- Adduction is movement toward the middle finger
- Everything the middle finger doe is abduction
- All the muscles in the middle finger that cause action are abductors
- Flexion of the thumb is towards the thumb and extension of the thumb is away from the palm
- Adduction of the thumb is 90 degrees forward from the palm, abduction of the thumb is toward the thumb
- Gripping requires opposition of the thumb
Where is the entire blood supply of the upper limbs derived from?
Where do these arteries start?
What are important branches of these arteries?
Where do they end?
What does they become at this point?
- The entire blood supply of the upper limb is derived from the subclavian arteries
- The subclavian arteries start at the brachiocephalic trunk (right) and the aortic arch (left)
- 2 relevant branches of the subclavian arteries are the dorsal scapular and suprascapular arteries
- The subclavian artery finishes at the lateral border of the fist rib, and becomes the axillary artery
Where does the axillary artery run from and to?
What does It become after this point?
What occurs to the axillary artery as it passes posterior to the pectoralis minor?
What are the names of these branches?
What do they supply?
What is he pneumonic for these arteries?
- The axillary runs from the lateral border of the1st rib to the inferior border of the teres major
- After this point, the axillary artery becomes the brachial artery
- As the axillary artery crosses posterior to the pectoralis minor it splits into 3 parts:
1) Part 1 is before the pectoralis minor and has 1 branch
• The superior thoracic artery
• Supplies the lateral thoracic wall and the first 2 intercostal spaces
2) Part 2 is behind the pectoralis minor and has 2 branches
• Thoraco-acromial artery
• Comes out as 4 branches that supplies the pectoral, deltoid, acromial and clavicular region, which they are named after
- Lateral thoracic artery
- Passes down the lateral aspect of the thorax
3) Part 3 is after the pectoralis minor and has 3 branches
• Subscapular artery
• Passes posteriorly and is quite large, because it takes part in another anastomosis in the upper limb
- Anterior and Posterior circumflex humeral arteries
- These arteries anastomose with one another round the surgical neck of the humerus
- Pneumonic for these arteries: Screw The Lawyer Save A Patient
- S- Superior thoracic artery
- T – Thoracic acromial artery
- L – Lateral thoracic artery
- S - Subscapular artery
- A – Anterior circumflex humeral artery
- P – Posterior circumflex humeral artery
