M3-5-Palm of hand

Carpal tunnel boundaries

Posterior: carpals

Anterior: transverse carpal ligaments

Carpal tunnel contents

Median n, 4 tendons of flexor digitorum superficialis, 4 tendons of flexor digitorum profundus, 1 tendon of flexor pollicis longus

Superficial palmar arch

Derived form ulnar a

Deep palmar arch

Derived from radial a

Common palmar digital arteries

Branches of superficial palmar arch , branches into 2 proper palmar digital arteries each

Ulnar n divisions into hand

Ulnar n → superficial branch of ulnar n → deep branch of ulnar n → common palmar digital n → proper palmar digital n (Part of IV-V)

Median n divisions into hand

Median n → recurrent branch of median n, common palmar digital n → proper palmar digital n (II, III, parts of IV)

Superficial branch of ulnar n innervations

Median palm and digits V and medial side of IV

Deep branch of ulnar n innervtaions

Motor innervations to most of the intrinsic muscles of the hand

Proper palmar digital nerves innervations

Refer to nerves that run on one side of a free part of a digit

Recurrent branch of median nerve innervation

Motor innervations of thenar muscles

Thenar muscles (digit I) origin

Transverse carpal ligament and adjacent carpals

Flexor pollicis brevis insertion

Proximal phalanx I

Flexor pollicis brevis action

flexion of pollex

Abductor pollicis brevis insertion

Proximal phalanx I

Abductor pollicis brevis actions

Abduction of pollex

Opponens pollicis insertion

Metacarpal I

Opponens pollicis actions

opposition of pollex

Hypothenar muscles

muscles in digit V region

Flexor digiti minimi insertion

Proximal phalanx V

Abductor digiti minimi actions

abduction of digit V

Opponens digiti minimi insertion

Metacarpal v

Adductor pollicis origin of transverse head

Metacarpal III

Adductor pollicis origin of oblique head

adjacent carpals

Adductor pollicis insertion

proximal phalanx I

Adductor pollicis actions

Adduction of pollex

Lumbricals origin

Flexor digitorum profundus tendon

Lumbricals insertion

Extensor expansion

Lumbricals actions

Simutaneous flexion of MCP and extension of PIP and DIP joints

Interosseous muscles

Palmar and Dorsal interossei

Palmar interossei origin

Metacarpal shaft

Palmar interossei insertion

proxinal phalanx and extensor expansion

Palmar interossei actions

Adduction of digits II, IV, V

Simultaneous flexion of MCP an extension of PIP and DIP joints

Dorsal interossei origin

Adjacent metacarpal shafts

Dorsal interossei insertions

Proximal phalanx and extensor expansion

Dorsal interossei actions

Abduction of digit II III IV, simultaneous flexion of MCP and extension of PIP and DIP joints

The median n innervates what in the hand

Lateral two lumbricals

Recurrent branch of median n innervates

The three thenar muscles

Deep branch of ulnar n innervates

All other intrinsic hand muscles (medial 2 lumbricals, hypothenar muscles, adductor pollicis and interossei)

Lumbricals (and interossei) function with extrinsic digital flexors and extrinsic digital extensors to:

Balance out forces at MCP, PIP, DIP and permit simultaneous extension

Proximal median n motor deficits

Weakened flexion of hand accompanied by addiction

inability to pronate forearm

inability to oppose digit I

Inability to flex digits I-III

Proximal median n sensory deficits

Lateral surface of palm

Tips of lateral 3 and half digits (I II III and lateral IV)

Hand of benediction

When trying to make a fist, only digits IV and III flex

Carpal tunnel syndrome sensory effects

Pain or paresthesia (numbness/tingling)

Lateral surface of palm

tips of lateral 3 and half

Carpal tunnel syndrome motor effects

may have weakness of thenar muscles

Lesion of recurrent branch of median n motor deficits

inability to oppose digit I

Lesion of recurrent branch of median n sensory deficits

none

Distal ulnar n motor deficits

inability to adduct or abduct digits II-V

Inability to extend digits IV-V at MCP, PIP, DIP joints simultaneously

Distal ulnar n sensory deficits

Medial surface of palm

Medial surface of dorsum

Tips of medial 1 and half digits (V and medial side of IV)

Ulnar claw hand

When trying to extend all digits, digits IV and V assume claw positions (MCP hyperextended, PIP strongly flexed, DIP in extended/neutral position)