Orthopaedic Anatomy and Approaches Flashcards
(221 cards)
Describe the boundaries of the cubital fossa
- Proximally - imaginary line running between the medial and lateral epicondyles of the humerus
- Laterally - brachioradialis muscle
- Medially - pronator teres muscle running from medial epicondyle to lateral aspect of the radial shaft
- Roof - deep fascia
- Floor - brachialis and elbow joint capsule
List the contents of the cubital fossa from medial to lateral
- Median nerve
- Brachial artery with flanking venae comitantes
- Biceps tendon
Describe the course of the brachial artery
- Continuation of the axillary artery
- Commences at the lower border of the latissimus dorsi tendon
- Ends at the level of the radial neck by dividing into ulnar and radial arteries
List the branches of the brachial artery
- Profunda brachii (accompanying the radial nerve)
- Superior ulnar collateral artery
- The Nutrient artery (to the humerus)
- Inferior ulnar collateral artery
Describe the course of the axillary nerve
Arises from the posterior cord of the brachial plexus and winds around the surgical neck of the humerus in company with the posterior circumflex humeral vessels through the quadrangular space.
Outline how the brachial plexus is divided
- 5 Roots
- 3 Trunks
- 6 Divisions
- 3 Cords
- 5 Terminal branches
Describe the deforming forces in midshaft clavicle fractures
- SCM pulls medial fragment upward
- Trapezius moves lateral fragment upward
- Pectoralis major pulls lateral fragment medially
- Latissium dorsi pulls arm and lateral fragment downward
Outline the bounds of the Quadrangular space
- Lateral = surgical neck of humerus
- Medial = long head of triceps
- Superior = teres minor
- Inferior = teres major
Contents of the Quadrangular space
- Axillary nerve
- Posterior circumflex humeral artery
Outline the bounds of the Triangular space
- Superior = Teres minor
- Inferior = Teres major
- Lateral = Long head of triceps
Contents of the Triangular Interval
- Radial nerve
- Profunda Brachii Artery
Axillary nerve root value
C5 and C6 (Posterior Cord)
Branches of the superior trunk of the brachial plexus
- Suprascapular nerve
2. Nerve to subclavius
Long thoracic nerve root value
C5-7
What divides the axillary artery into 3 parts
Pectoralis minor muscle
Motor supply of the Axillary nerve
- Deltoid
- Teres minor
- Long head of triceps
Radial nerve root value
C5-T1 (Posterior cord)
Motor supply of the radial nerve
- Triceps brachii
- Brachioradialis
- ECRL
- Anconeus
Motor supply of PIN
All forearm extensors
Describe the path of the radial nerve proper
- Formed from the posterior cord of the brachial plexus
- Moves through the Triangular interval
- Moves along the spiral groove of the humerus in the posterior compartment of the arm
- Travels with Profunda brachii artery and pierces the lateral intermuscular septum 5cm proximal to the elbow to enter anterior compartment
- Lies anterior to the lateral epicondyle before splitting at the level of the radial head
- Divides into superficial radial nerve (sensory) and PIN (motor)
Contents of the Triangular space
Circumflex scapular artery
Bounds of the Triangular interval
- Medial = surgical neck of humerus
- Lateral = long head of triceps
- Superior = Teres major
Describe the path of the superficial radial nerve
- Runs on the lateral side of the radius beneath brachioradialis
- Enters posterior compartment proximal to the wrist
- Superficial branches run superficial to the tendons of the snuffbox to supply the dorsum of the hand
Describe the path of the Posterior Interosseous Nerve (PIN)
- Pierces the supinator 3cm distal to the radial head
- Lies in the extensor forearm compartment beneath the IO membrane to the wrist
- Supplies supinator and all forearm extensors