T2 L7 Anatomy of the forearm Flashcards
What type of joint is the elbow joint and what movement does it allow?
Synovial hinge joint for flexion / extension
What type of joint is the proximal radioulnar joint and what type of movement does this allow?
Pivot joint for supination / pronation
What are the 3 ligaments of the forearm?
Radial collateral ligament
Ulnar collateral ligament
Annular ligament
Describe the radial collateral ligament
From lateral epicondyle and blends with annular ligament of radius
Describe the ulnar collateral ligament
From medial epicondyle and attaches to coronoid process and olecranon of ulna
Describe the annular ligament
Forms a cuff around proximal radioulnar joint to hold radial head in place
What is the cubital fossa?
Triangle region over anterior elbow
What is the cubital fossa bordered by?
Line joining lateral epicondyle and medial epicondyle
Brachioradialis
Pronator teres
What is contained in the cubital fossa?
Lateral cutaneous nerve to forearm
Biceps tendon
Brachial artery
Median nerve
What does the medial cubital vein do?
Drains anterior forearm
Forms bridge between basilic and cephalic vein
What are the 2 compartments of the forearm?
Flexor compartment (anterior forearm) Extensor compartment (posterior forearm)
What are the 3 groups of muscles in the anterior forearm?
Superficial muscles
Intermediate muscles
Deep muscles
What muscles are in the superficial layer of the anterior forearm?
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnari
What is the origin, insertion, function and innervation of pronator teres?
Origin: medial epicondyle (CFO), coronoid process of ulna
Insertion: mid-shaft of radius
Function: pronation of forearm
Innervation: median nerve
What is the origin, insertion, function and innervation of flexor carpi radialis?
Origin: medial epicondyle (CFO)
Insertion: base of metacarpals II and III
Function: flexion and abduction at wrist
Innervation: median nerve
What is the origin, insertion, function and innervation of palmaris longus?
Origin: Medial epicondyle (CFO)
Insertion: flexor retinaculum of wrist
Function: flexion at wrist
Innervation: median nerve
What is the origin, insertion, function and innervation of flexor carpi ulnaris?
Origin: medial epicondyle (CFO) and ulna
Insertion: pisiform carpal bone
Function: flexion and adduction at wrist
Innervation: ulnar nerve
What is Golfers elbow?
Epicondylitis at CFO
Tendon inflammation due to overuse / excessive gripping
What muscle is in the intermediate layer of the anterior compartment?
Flexor digitorum superficialis
What is the origin, insertion, function and innervation of flexor digitorum superficialis?
Origin: CFO (medial epicondyle)
Insertion: 4 tendons go to middle phalanges of digits 2-5
Function: flexion at metacarpophalangeal and proximal interphalangeal joints of digits 2-5, flexion at wrist
Innervation: median nerve
What are the muscles in the deep layer of the anterior compartment?
Flexor digitorum profundus
Flexor pollicis longus
Pronator quadratus
What is the origin, insertion, function and innervation of flexor digitorum profundus?
Origin: ulna and interosseous membrane
Insertion: distal phalanges of digit 2-5
Innervation: ulnar and median nerve
Function: flex distal interphalangeal, metacarpophalangeal and wrist joints
What is the origin, insertion, function and innervation of flexor policis longus?
Origin: anterior surface radius and interosseous membrane
Insertion: Distal phalanx of digit 1
Function: flexes interphalangeal and metacarpophalangeal joint of thumb
Innervation: median nerve
What is the origin, insertion, function and innervation of pronator quadratus?
Origin: anterior surface of ulna
Insertion: anterior surface of radius
Function: pronates forearm
Innervation: median nerve
What are the 2 groups of muscles in the posterior compartment of the forearm?
Superficial
Deep
What are the superficial muscles in the posterior compartment?
Extensor carpi radialis brevis Extensor carpi radialis longus Extensor digitorum Extensor digiti minimi Extensor carpi ulnaris Brachioradialis Anconeus
What is the origin, insertion, function and innervation of extensor carpi radialis brevis?
Origin: lateral epicondyle (CEO)
Insertion: metacarpal bones II and III
Function: extends and abducts wrist
Innervation: radial nerve
What is the origin, insertion, function and innervation of extensor carpi radialis longus?
Origin: supracondylar ridge
Insertion: metacarpal bones II and III
Function: extends and abducts wrist
Innervation: radial nerve
What is the origin, insertion, function and innervation of extensor digitorum?
Origin: lateral epicondyle
Insertion: 4 tendons insert into digits 2-5 in middle and distal phalanges
Function: extends digits 2-5
Innervation: radial nerve
What is the origin, insertion, function and innervation of extensor digiti minimi?
Origin: lateral epicondyle of humerus
Insertion: extensor hood of digit 5
Function: extends digit 5
Innervation: radial nerve
What is the origin, insertion, function and innervation of extensor carpi ulnaris?
Origin: lateral epicondyle humerus
Insertion: dorsal side metacarpal 5
Function: extension and adduction of wrist
Innervation: radial nerve
What is the origin, insertion, function and innervation of brachioradialis?
Origin: Proximal aspect of lateral supracondylar ridge of humerus
Insertion: distal end of radius
Function: flexion at elbow
Innervation: radial nerve
What is the origin, insertion, function and innervation of anconeus?
Origin: lateral epicondyle
Insertion: posterior and lateral parts of olecranon
Function: stabilises and extends elbow. abducts ulna during pronation of forearm
Innervation: radial nerve
What is tennis elbow?
Epicondylitis at CEO
Tendon inflammation due to overuse / forceful extension
What muscles form the deep layer in the posterior compartment?
Supinator Abductor pollicis longus Extensor pollicis brevis Extensor pollicis longus Extensor indicis
What is the origin, insertion, function and innervation of supinator?
Origin: lateral epicondyle of humerus, posterior surface of ulna
Insertion: posterior surface of radius
Function: supinates forearm
Innervation: radial nerve
What is the origin, insertion, function and innervation of abductor pollicis longus?
Origin: interosseous membrane and posterior surfaces of radius and ulna
Insertion: lateral side of base of metacarpal I
Function: abducts thumb
Innervation: radial nerve
What is the origin, insertion, function and innervation of extensor pollicis brevis?
Origin: posterior surface of radius and interosseous membrane
Insertion: base of proximal phalanx of thumb
Function: extends at metacarpophalangeal and carpometacarpal joints of thumb
Innervation: radial nerve
What is the origin, insertion, function and innervation of extensor pollicis longus?
Origin: posterior surface of ulna and interosseous membrane
Insertion: distal phalanx of thumb
Function: extends all joints of thumb
Innervation: radial nerve
What is the origin, insertion, function and innervation of extensor indicis?
Origin: posterior surface of ulna and interosseous membrane
Insertion: extensor hood of digit 2
Function: extend digit 2
Innervation: radial nerve
What are the borders of the anatomical snuff box?
Medially - tendons of extensor pollicis longus
Laterally - tendons of abductor pollicis longus and extensor pollicis brevis
Proximally - styloid process of radius
Floor - carpal bones, scaphoid, trapezium
Roof - skin
What muscles perform wrist abduction?
Flexor carpi radialis
Extensor carpi radialis (longus and brevis)
What muscles perform wrist adduction?
Flexor carpi ulnaris
Extensor carpi ulnaris
What muscles perform supination?
Biceps brachii
Supinator
What muscles perform pronation?
Pronator teres
Pronator quadratus
What is the function of flexor retinaculum?
Prevents bowing of tendons
What is contained in the carpal tunnel?
Median nerve
Flexor pollicis longus
Flexor digitorum superficialis
Flexor digitorum profundus
What is carpal tunnel syndrome?
Median nerve compression due to increased pressure in carpal tunnel
Associated with trauma, obesity and pregnancy
What is the function of extensor retinaculum?
Prevents bowing of tendons
Separates tendons into compartments
What does the brachial artery divide into?
Radial artery
Ulnar artery
What muscle does the radial artery pass under?
Brachioradialis
What muscle does the ulnar artery pass under?
Flexor carpi ulnaris
What artery does the common interosseous branch from?
Ulnar artery
What are the 2 branches of the radial nerve?
Superficial branch (sensory) Deep branch (motor)
What does the superficial branch of the radial nerve supply?
Lateral dorsum of hand
What does the deep branch of the radial nerve supply?
Posterior compartment
What does the anterior interosseous nerve branch from?
Median nerve
What does the median nerve supply?
Motor: anterior compartment except FCU / medial part FDP
Sensory: lateral palm, D1, D2, D3, 1/2 D4
What does the ulnar nerve supply?
Motor: FCU and medial part FDP
Sensory: medial hand, 1/2 D4, D5
