Forearm
The Cubital fossa
Boundaries: lateral: bracioradialis medial border: pronator teres upper border: elbow joint Contents - median n., radial n., Brachial a. (splits into radial and ulnar at this point), biceps tendon
Thenar Compartment
Flexor Pollicis Brevis, Abductor pollicis brevis, Opponens pollicis N: Recurrent branch of median nerve *in serious carpal tunnel there is atrophy of the thenar eminence
Hypothenar Compartment
Flexor digiti minimi, Abductor digiti minimi, Opponens digit minimi (deep) N: deep branch of the ulnar nerve
Flexor digitorum superficialis
Intermediate layer O: common flexor tendon and ant. radius and ulna I: 4 tendons to middle phalanges of 4 medial digits (not thumb) N: median N. F: flexion of proximal interphalangeal joints
Supinator
O: Lateral epicondyle I: Wraps around proximal radius N: Deep branch radial nerve F: supination *synergistic with the biceps
Flexor Carpi ulnaris
O: Medial epicondyle I: 5th metacarpal N:ulnar N. F: wrist flexion and adduction superficial layer
Flexor Pollicis Longus
O: Radial shaft I: Distal phalanx - 1st digit - thumb N: Median nerve - ant. IO branch F: flexes phalanges of thumb deep layer
Dorsal Interossei
O: adjacent metacarpals I: extensor hood bases of proximal phalanges 2-4 N: Deep brach ulnar nerve DAB - dorsal abducts deepest group of the hand
Flexor Digitorum Profundus
O: ant. ulna and IO membrane I: bases distal phalanges 4 medial digits N: medial 2 tendons = ulnar nerve lateral 2 tendons- ant. IO branch (median nerve) F: flexion in the metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal joints (DIP) of the second to fifth fingers as well as the wrist joint deep layer
Flexor Carpi Radialis
O: common flexor tendon I: 2nd and 3rd metacarpals N: median N. F: wrist flexion and abduction superficial layer
Pronator Teres
O: common flexor tendon I: lateral radial shaft N: median N. F: pronation superficial layer
Palmaris Longus
O: common flexor tendon I: palmar aponeurosis N: median N. F: support the palmar aponeurosis *absent in 15-20% of the population- test by touching thumb to pinky - more digital motion now - less need for it used in tendon transfers (grafts) superficial layer
Extensor Digitorum
O: lateral epicondyle I: bass of the middle and distal phalanges (2-5) N: deep branch radial nerve F: MCP/IP joint extension *intertendinous connections superficial
Extensor Carpi Radalis Longus
O: lateral epicondyle I: dorsal base of 2nd metacarpal N: radial nerve F: extend and abduct /radially deviate wrist
Extensor carpi radialis brevis
O: lateral epicondyle I: dorsal base of 3rd metacarpal N: deep branch radial nerve F: extend and abduct/radially deviate wrist superficial
Extensor Digiti minimi
O: lateral epicondyle I: extensor hood N: deep branch radial n. F: extension of the 5th digit , McP, and IP
Brachioradialis
O: lateral epicondyle I: radial styloid process N: radial nerve F: elbow flexion doesn't cross the wrist joint - doesn't flex
Palmar interossei
O: metacarpals 2,4,5 I: extensor hood bases of prox. phalanges 2,4,5 N: deep branch ulnar nerve only 2,4,5 - middle finger can't adduct and adductor pollicis takes care of the thumb
Adductor Pollicis
O: oblique head- capitate and base of metacarpals 2 &3 Transverse head- body of metacarpal 3 I: Base of proximal phalanx N: deep branch ulnar nerve F: Adducts the thumb looks like a fan
Pronator Quadratus
O: ulna I: radius N: anterior IO branch (median) F: forearm pronation deep layer
Lumbricals
O:Tendons of the flexor digitorum profundus I: Lateral sides of the extensor hood in fingers 2-5 F: flex the MCP and extend the PIP and DIP - bye bye muscles N: half by median nerve (fingers 2-3) and half by deep branch of the ulnar nerve (fingers 4-5)
Extensor Carpi Ulnaris
O:lateral epicondyle I: ulnar side of the base of the 5th metacarpal N: deep branch radial nerve F: extend and adduct/ulnar deviation of the wrist
lateral fascial compartment
brachioradialis and extensor carpi radialis longus
Superficial layer of forearm
pronator teres, flexor carpi radialis, palmaris longus, and carpi ulnaris
Deep Group arm - posterior fascial compartment
supinator, abductor pollicis longus, extensor pollicis longus, extensor pollicis brevis, extensor indicis
