Forearm Flashcards
Captiulum
Lateral condyle of the humerus
- Articulates with radial head
Trochlea
Medial condyle of humerus
Articulates with ulnar head
Olecranon
Proximal, posterior section of the ulna
- Articulates with the posterior depression in the distal humerus
Forms bony prominence when elbow is bent
Elbow joint
- Articulation
- Type
- Movements
Articulations:
- Humeroulnar
- Humeroradial
- Proximal radioulnar
Type
- Synovial hinge joint (Humeroulnar)
- Synovial pivot (PRU)
Movement
- Hinge: Flexion, extension
- PRU: pronation and supination of hand.
Radial collateral ligament of elbow
From the lateral epicondyle to annular ligament
Stabilises joint
Annular ligament of elbow
From radial notch of the ulnar
- Encircles head of radius
Stabilises radius against radial notch of ulna
- Permits supination and pronation
Ulnar collateral ligament of elbow
From lateral epicondyle to supinator crest on ulna
Cubital fossa
- Borders
Triangular region over anterior elbow
Boundaries: Base of triangle: Line between medial and lateral epicondyle - Medially= pronator teres - Laterally= brachioradialis - Bed= brachial
Content
- Brachial artery
- Biceps tendon, Bicipital aponeurosis
- Median nerve
- median cubital vein
Related structures
- Ulnar nerve passes medially
- Radial nerve passes laterally
Origin of superficial forearm flexors
Common flexor origin
- Medial epicondyle
Pronator teres
- Origin+ insertion
- Innervation
- Action
- Related structures
Origin
- Medial epicondyle [common flexor tendon]
- Medial supra-epicondyle ridge
Insertion
- Lateral mid-shaft of radius
Innervation
- Median nerve
Action
- Pronation of forearm
- Flexion at elbow
Related structures
- Medial border of the cubital fossa
- Median nerve enters the forearm between its two heads
- Inserts distally to supinator
Common flexor tendon
- Origin
- Muscles that attach [5]
Tendon from the medial epicondyle that serves as origin of attachment for:
- Flexor carpi ulnaris
- Palmaris longus
- Flexor carpi radialis
- Pronator teres
- Flexor digitorum superficialis
Flexor carpi radialis
- Origin+ insertion
- Innervation
- Artery
- Action
- Related structures
Origin
- Common flexor tendon
Insertion
- Base of metacarpal 2,3.
Innervation
- Median nerve
Artery
- ulnar
Action
- Flexion at wrist
- Abduction at wrist
Related structures
- Originates lateral and superficial to FDS
Flexor carpi ulnaris
- Origin+ insertion
- Innervation
- Artery
- Action
Origin
- Common flexor tendon
Insertion
- Pisiform
- Hook of hamate
- Base of 5th metacarpal
Innervation
- Ulnar nerve
Artery
- ulnar
Action
- Flexion at wrist
- Adduction at wrist
Palmaris longus
- Origin+ insertion
- Innervation
- Artery
- Action
Origin
- Common flexor tendon
Insertion
- Palmar aponeurosis into distal phalanges 2-5
- Flexor retinaculum
Innervation
- Median nerve
Artery
- ulnar
Action
- Flexion at wrist
Flexor digitorium Superficialis
- Origin+ insertion
- Innervation
- Artery
- Action
- Related structures
Origin
- Common flexor tendon
- Oblique line of radius
Insertion
- Middle phalanges 2-5
Innervation
- Median nerve
Artery
- Ulnar
Action
- Flexion of MCP and PIP for d2-5
- Flexion of wrist
Related structures:
- Tendons travel in carpal tunnel
- Tendon creates chimes to allow FDF tendons to pass
Flexor digitorium profundus
- Origin+ insertion
- Innervation
- Artery
- Action
- Related structures
Deep muscle
Origin
- Anteromedial surface of ulna
- Adjacent interosseous membrane
Insertion
- Distal phalanx d2-5
Action
- Flexion of DIP, Wrist, MCP, PIP
Innervation
- Anterior interosseous (median)
- Ulnar
Artery
- Anterior interosseous (Ulnar)
Related structures
- Tendons run through carpal tunnel, deep to FDS
- Origin of lumbrical muscles (radial side)
Flexor Pollicus longus
- Origin+ insertion
- Innervation
- Artery
- Action
- Related structures
Origin
- Anterior radial surface
- Radial half of interosseous membrane
Insertion
- Base of distal phalanx of D1
Action
- Flexion of IP, MCP joint of thumb
Innervation
- Anterior interosseous (median)
Artery
- Anterior interosseous (Ulnar)
Related structures
- Tendons run through carpal tunnel, lateral to other tendons
- Anterior interosseous artery and vein passes between it and FDP
Pronator Quadratus
- Origin+ insertion
- Innervation
- Artery
- Action
Origin
- Medial, anterior, distal ulnar
Insertion
- Lateral, anterior, distal radius
Innervation
- Anterior interosseous (median)
Artery
- Anterior interosseous (Ulnar)
Action
- Pronation of forearm
Supinator
- Origin+ insertion
- Innervation
- Artery
- Action
Origin
- Lateral epicondyle of humerus
- Supinator crest of ulnar
Insertion
- Lateral, proximal radial surface
Innervation
- Radial
Artery
- Radial
Action
- Supination
Brachioradialis
- Origin+ insertion
- Innervation
- Artery
- Action
- Related structures
Origin
- Lateral, supraepicondylar ridge of humerus
Insertion
- Styloid process of radius
Innervation
- Radial
Artery
- Radial
Action
- Flexion then half pronated
- Supination when extended
Related structures
- Radial nerve runs deep
- Forms lateral border of cubital fossa
Anconeus
- Origin+ insertion
- Innervation
- Action
Origin
- Lateral epicondyle of humerus
Insertion
- Olecranon of ulnar
Action
- Stabilises elbow during pronation and supination
Innervation
- Radial
Extensor carpi radialis
- Origin+ insertion
- Innervation
- Action
Two parts: Brevis and longus
Origins:
Longus- Supraepicondylar ridge of humerus
Brevis- Common extensor tendon
Insertion
- Dorsal base of 2nd metacarpal (longus)
- Base of 3rd MC (brevis)
Action
- Extension of wrist
- Abduction of wrist
Innervation
- Radial
Extensor carpi ulnaris
- Origin+ insertion
- Innervation
- Artery
- Action
Origin
- Common extensor tendon
Insertion
- Base of 5th metacarpal
Innervation
- Radial
Artery
- Ulnar
Action
- Extension of wrist
- Adduction of wrist
Extensor digitorium
- Origin+ insertion
- Innervation
- Artery
- Action
Origin
- Common extensor tendon
Insertion
- Extensor hoods into middle and distal phalanges of D2-5
Innervation
- Posterior interosseous (Radial)
Action
- Extension of wrist and digits
Extensor digit minimi
- Origin+ insertion
- Innervation
- Artery
- Action
Origin
- Common extensor tendon
Insertion
- Extensor hood into of d5
Action
- Extension of D5, wrist
Innervation
- Radial
Extensor pollicus brevis
- Origin+ insertion
- Innervation
- Action
Origin
- Radius, interosseous membrane
Insertion
- Dorsal base of proximal phalanx of thumb.
Innervation
- Radial
Action
- Extension of thumb at MCP, CM
Extensor pollicus longus
- Origin+ insertion
- Innervation
- Action
Origin
- Ulnar, interosseous membrane
Insertion
- Dorsal base of distal phalanx of thumb.
Innervation
- Radial
Action
- Extension of thumb at MCP, IP joints
Abductor pollicus longus
- Origin+ insertion
- Innervation
- Action
Origin
- Posterior ulnar and radial surface
- interosseous membrane
Insertion
- Base of 1st metacarpal
Action
- Abduction of thumb
- Extension of thumb
Innervation
- Radial
Extensor indicis
- Origin+ insertion
- Innervation
- Action
Origin
- Distal ulna
- Interosseous membrane
Insertion
- Extensor hood of D2
Action
- Extension of D2
- Extensor of wrist
Innervation
- Radial
Radial nerve
From posterior cord
Enters forearm laterally, under brachioradialis
Branch
- Superficial= sensory
- Deep= motor
Sensory
- Posterior arm
- Dorsum of hand
- Posterior forearm
- Inferior lateral arm
Motor
- Posterior interosseous= extensors of forearm
- Supinator
- Triceps
- Brachioradialis
- Anconeus
Ulnar nerve
From medial cord
- Enters the cubital tunnel
Motor
- Flexor carpi ulnaris
- Medial half of flexor digitorium profundus
- Intrinsic hand muscles (lat. 2 lumbricals)
Sensory
- Medial hand, digits 1/2(4), 5
median nerve
Travels between FDS, FDP
Motor
- Flexors of forearm( XC Flexor carpi ulnaris)
- Anterior interosseous = deep flexors, including Radial half of FDP
Sensory
- Lateral palm
- Later 3.5 digits
