UE Regions

• What is another name for the axilla?

  Armpit
• What shape is the axilla?

  Pyramid-shaped
• What is one of the primary functions of the axilla?

  Passageway for nerves, blood, and lymph vessels from neck to upper extremity
• How does the axilla protect neurovascular structures?

  By being adducted
• What are the two ends of the axilla called?

  • Apex: Upper end directed into the root of the neck
  • Base: Lower end formed by skin, hypodermis, and deep fascia
• What bounds the apex of the axilla?

  Clavicle (anterior), upper border of scapula (posterior), and outer border of 1st rib (medial)
• What forms the base of the axilla?

  Skin, hypodermis, and deep fascia
• What are the boundaries of the base of the axilla?

  Bounded by anterior axillary line (AAL), posterior axillary line (PAL), and chest wall (medial)
• What are the walls of the axilla?

  • Anterior: Pectoralis major, subclavius, pectoralis minor
  • Posterior: Subscapularis, latissimus dorsi, teres major
  • Medial: Upper 4-5 ribs and intercostal space covered by serratus anterior
  • Lateral: Coracobrachialis, biceps brachii in bicipital groove
• What are the contents of the axilla?

  Axillary artery and its branches, axillary vein and its tributaries, lymph vessels and nodes, brachial plexus
• Name one nerve of the superficial part of the back.

  Spinal accessory
• What are the muscles of the superficial part of the back?

  • Trapezius
  • Latissimus dorsi
  • Levator scapulae
  • Rhomboids
• What is the cubital fossa?

  A triangular depression that lies in front of the elbow
• What are the boundaries of the cubital fossa?

  • Lateral: Brachioradialis
  • Medial: Pronator teres
  • Base: Imaginary line between the two epicondyles of the humerus
  • Floor: Supinator and Brachialis
  • Roof: Fascia, hypodermis, skin
• What are the contents of the cubital fossa from medial to lateral?

  Median nerve, bifurcation of brachial artery, tendon of biceps brachii, radial nerve
• What are the contents of the anterior compartment of the forearm?

  • Muscles: Flexor-pronator (superficial, intermediate, and deep groups)
  • Blood supply: Ulnar and radial arteries
  • Nerve supply: Median and ulnar nerves
• What are the contents of the lateral compartment of the forearm?

  • Muscles: Extensor-supinator; APL (Brachioradialis and ECRL)
  • Blood supply: Radial and brachial arteries
  • Nerve supply: Radial nerve
• What are the contents of the anterior compartment of the arm?

  • Muscles: Biceps brachii, coracobrachialis, brachialis
  • Blood supply: Brachial artery
  • Nerve supply: Musculocutaneous nerve
• What muscles are found in the posterior compartment of the arm?

  Triceps brachii
• What is the blood supply for the posterior compartment of the arm?

  Profunda brachii and ulnar collateral arteries
• What is the nerve supply for the posterior compartment of the arm?

  Radial nerve
• What is the function of the flexor retinaculum?

  • Thickening of deep fascia
  • Holds the long flexor tendons in position at the wrist
  • Forms the carpal tunnel
• What are the attachments of the flexor retinaculum?

  • Medial: Pisiform and hook of hamate
  • Lateral: Scaphoid and trapezium
• What forms the carpal tunnel?

  • Anterior surface of carpals
  • Flexor retinaculum
• What are the contents of the carpal tunnel?

  Median nerve, 4 tendons of FDS, 4 tendons of FDP, tendon of FPL
• What structures are superficial to the flexor retinaculum from medial to lateral?

  1. FCU tendon
  2. Ulnar nerve
  3. Ulnar artery
  4. Palmar cutaneous branch of ulnar nerve
  5. PL tendon
  6. Palmar cutaneous branch of median nerve
• What structures are beneath the flexor retinaculum from medial to lateral?

  1. FDS tendon
  2. Median nerve
  3. FPL tendon
  4. FDP tendon
• What structures are superficial to the extensor retinaculum from medial to lateral?

  1. Dorsal cutaneous branch of ulnar nerve
  2. Basilic vein
  3. Cephalic vein
  4. Superficial branch of radial nerve
• What structures are beneath the extensor retinaculum from medial to lateral?

  1. 1st dorsal tunnel: APL and EPB tendons
  2. 2nd dorsal tunnel: ECRL and ECRB tendons
  3. 3rd dorsal tunnel: EDC and EIP tendons
  4. 4th dorsal tunnel: EDC and EIP tendons
  5. 5th dorsal tunnel: EDM tendon
  6. 6th dorsal tunnel: ECU tendon
• What is the function of the extensor retinaculum?

  • Thickening of deep fascia
  • Holds the long extensor tendons in position at the wrist
  • Forms the dorsal tunnels
• What are the attachments of the extensor retinaculum?

  • Medial: Pisiform and hook of hamate
  • Lateral: Distal end of radius
• What is the anatomical snuffbox?

  • A triangular skin depression on the lateral side of the wrist
  • Significance: Palpation of the scaphoid and radial artery
• What are the boundaries of the anatomical snuffbox?

  • Lateral: APL and EPB
  • Medial: EPL
  • Floor: Styloid process of radius, scaphoid & trapezium, base of 1st metacarpal
  • Within: Radial artery
• What is the function of synovial flexor sheaths?

  • Minimize friction beneath the flexor retinaculum and fibrous flexor sheaths
  • Forms radial bursa (synovial sheath of FPL) and ulnar bursa (synovial sheath of FDS and FDP)
• What are the contents of the synovial flexor sheaths?

  1. Thumb: FPL
  2. Fingers: FDP and FDS
• What is the extensor expansion?

  • AKA 'dorsal hood'
  • Fascial expansion on the posterior surface of each finger
  • 3 parts: Central (inserted into base of middle phalanx) and 2 lateral parts (inserted into base of distal phalanx)
• What tendons are attached to the extensor expansion?

  1. EDC
  2. Lumbricals
  3. Interossei
• What are annular pulleys?

  • AKA 'vaginal ligament'
  • Forms fibro-osseous tunnels where long flexor tendons pass
  • Function: Prevent bowstringing of tendons