Wrist & Hand Flashcards
The concavity of the carpal bones are formed in what direction?
anteriorly
What are the 8 carpal bones from the anterior view, lateral to medial the proximal row then distal row.
SLTPTTCH
Scaphoid Lunate Triquestrum Pisiform
Trapezium Trapezioid Capitate Hamate
What is the ligament-like tissue that closes off the carpel tunnel from scaphoid tubercle, Trapezium to Hook of Hamate, Pisiform?
Transverse Ligament called Flexor Retinaculum
What structures and their total number is found deep to Volar and Transverse Carpal Ligament?
4- Flexor digitum superficialis
4- Flexor digitum profundus
1- Flexor Pollicus Longus
1- Median Nerve
Which sits deep and which sits superficial in the Flexor retinaculum?
Volar carpal ligament is SUP
Transverse carpal ligament is DEEP
What structures travel just superficial to the Volar carpal ligament?
Palmaris longus tendon
Palmar cutaneous branches (FCU and FCR)
What 4 structures travel in between the Volar and Transverse Carpal ligament?
Ulnar nerve
Ulnar artery
Flexor carpi ulnaris
Flexor carpi radialis
What the orientation (MED/LAT/POST) of the three groups of content in the Carpal tunnel?
Flexor pollicus longus- MED
Flexor digitorum superficialis - LAT
Flexor digitorum profundus - POST
What is the opening that Ulnar nerve and Ulnar artery travels through superficial to the carpal tunnel found in between the transverse and Volar carpal ligament?
Guyon’s canal
What two branches of cutaneous nerves travel superficial to the Flexor retinaculum
Palmar branch of the Median nerve (LAT side)
Palmar branch of the Ulnar nerve (MED side)
What is the function of both Flexor and Extensor retinaculum?
holds the tendons in place to prevent Bow-stringing
The tendons along the dorsal wrist enters the hand via what openings? what is it deep to?
Six Dorsal compartments
Extensor retinaculum
What are the six dorsal compartments of the hand and it’s contents?
1st: Extensor pollicus brevis & Abductor pollicus longus
2nd: Extensor carpi radialis longus & brevis
3rd: Extensor pollicus longus
4th: 1 tendon of Extensor Indicies + 4 tendon of Extensor digitorum
5th- Extensor digitorum minimi
6th- Extensor carpi ulnaris
What is the dorsal compartments covered in and why?
synovial lining to help decrease friction
Flexor digitorum superficialis and flexor digitorum profundus are flexors that could cause bow-stringing. what prevents that?
flexor retinaculum
What distal structure is the level of the dorsal compartments located?
Lister’s Tubercle
Which dorsal compartments is most commonly injured/effected?
1st dorsal compartment aka Dequeivaine’s Tenosynovitis
What motion of the 1st dorsal compartment produces Dequeivaine’s tenosynovitis?
Abductor pollicus longus’ ABD the thumb + Extensor pollicus brevis EXT the thumb and also Radially deviate. Repetitive radial deviation commonly seen in new parents carrying the child
How do you test for Dequeivaine’s Tenosynovitis?
Make a fist and thumb inside the fist and cause excessive ulnar deviation. if much pain occurs its positive. this test is known as Finkelstein’s test
Which forearm bone extends the most distally? and what carpal bones will it articulate?
Radius as it articulates the scaphoid and lunate
What carpal bone articulates with the Ulna?
NONE! trick question the Triqetrum is just distal with a structure in between the ulna and triquestum
What is in between the ulna and triquestrum?
triangular fibrocartilagenous complex TFCC
what is the triangular fibrocarilagenous complex bordered by on the palmar and dorsal side? and its function
palmar side- palmar radio-ulnar ligament- limits supination
dorsal radio-ulnar ligament- limits pronation
What may result from a radius fracture?
the radius may set shorter than the ulnar
what is it called when the radius is set shorter than the ulnar after a radial fracture?
Ulnar positive
what can ulnar positive after a fracture result in?
impingement of the TFCC
what results when the radius was set much longer than the ulnar?
you get ulnar negative
what can ulnar negative result in?
abnormal articulation and movement of the carpal bones may occur
The wrist form a what sort of segment?
intercalated segment
What are the property of the intercalated segment on the wrist?
muscles on the carpal bones do not directly affect their movement.
how is the carpal bones dictated?
by tension applied to the numerous ligaments that attach to the carpals
what are the two joints involved in intricate carpal/wrist?
Radio-carpal joint
Midcarpal joint
what is the Radio-carpal joint?
Scaphoid and Lunate (convex) articulate with the distal radius (concave) as a synovial condyloid joint
what is the midcarpal joint?
formed between the proximal and distal rows of carpal bones also functioning as a synovial condyloid joint.
what are midcarpal and radiocarpal joint supported by?
medial and lateral collateral ligaments
how many DOF are in the wrist/carpal joints? and what are they?
2
Flexion/extension
ulnar/radial deviation
one DOF is more limited bc its a condyloid joint: flexion/extension is more mobile
what distal row of carpals articulate with what metacarpals?
trapezium- 1st meta
trapazoid -3nd meta
capitate-3rd meta
hamate- 4th & 5th
what sort of joints are the carpo-metacarpal joints of digits 2-5?
plane-synovial joints
the 1st and 5th CMC joints is what sort of joint?
synovial saddle joint
what motions occur at CMC joint?
- flexion/extension
- opposition/reposition
What sort of joints are all MCP joints?
condyloid
what motion occurs at MCP joints?
flexion/extension
adduction/abduction
what binds the 5 MCP joints together to limit abduction?
deep transverse ligament/ deep transmetacarpal ligament
what lies on the anterior surface of the MCP joints and limits hyperextension?
Palmar plates (fibrocartilage)
what limits movement in the coronal plane and become taught in flexion along the medial and lateral aspects of the MCP joints?
collateral ligaments
What joints are there for interphalangeal joints of digits 2-5?
Proximal interphalangeal joints
Distal interphalangeal joints
What joint does digit 1 have that is interphalangeal?
just a interphalangeal joint
what sort of joints are all interphalangeal joints?
synovial pivot joints
what structure limits hyperextension for the interphalangeal joints? and where is it oriented?
anteriorly is the palmar plates
What are the two ligaments on the sides of the interphalangeal joints? and when are they taught/tight?
medial and lateral collateral ligaments.
they are taught in both flexion and extension
how many DOF does interphalangeal joints have and what are the movements? and why?
1 DOF
flexion/extension
due to it being a synovial hinge joint most hinge like hinge joint
what is the very superficial aponeuroic tissue in the hand?
palmar apeneurosis
what muscle is continuous with palmar apeneurosis in the anterior forearm?
palmaris longus
what squarish muscle is on the medial portion of the palm that connects with the palmar apeneurosis?
palmaris brevis
what innervates the palmaris brevis?
superficial ulnar nerve
what innervates the palmaris longus?
median nerve
where does the palmar aponeurosis attach to?
superficially to the skin of the palm to create a tight grip in the palm. also extends to the metacarpal heads.
what tethers the palmar apeneurosis to the metacarpal heads?
superficial transverse metacarpal ligament
what is deep to the superficial transverse metacarpal ligament in the hand?
deep transverse metacarpal ligament
what nerve will not innervate any of the instrinsic muscles of the hand? and why?
Radial nerve.
bc radial nerve innervate only the dorsal hand and in the dorsal hand there is no intrinsic muscle
what nerves innervate the palmar side of the hand?
ulnar and median nerves or some form of their nerves.
What are the three groups of intrinsic hand muscles? and how are they oriented?
Hypothernar muscles: fleshy medial portion of the palm
Thenar muscles: fleshy disto-lateral portion of the palm
Short muscles: in the middle of the palm
what is the most medial muscle of the hypothenar muscles?
Abductor digiti minimi
what is the anterior muscle of the hypothenar muscles?
flexor digiti minimi brevis
why is there no flexor digiti minimi longus?
it is a vestigial muscle now no longer exists in the human hand
what is deep and in the middle of digiti minimi brevis and abductor digiti minimi?
opponens digiti minimi
what innervates all the hypothenar muscles?
deep ulnar nerve (this nerve is motor only)
what innervates the palmaris brevis muscle
superficial ulnar nerve
what does the superificial ulnar nerve turn into after innervating the palmaris brevis muscle?
cutaneous nerve branching from the ulnar nerve
what is the most lateral thenar muscle?
abductor pollicus brevis
where is the abductor pollicus longus? and innervated by?
posterior part of the hand part of the snuff box. innervated by the posterior interosseous nerve branch of the radial nerve.
what muscle is on the anterior aspect of the thenar eminence?
flexor pollicis brevis
where is the flexor pollicis longus?
anterior portion of the forearm at the same level as flexor digitorum profundus innervated by the anterior interosseous nerve branch of the median nerve
what nerve is in the thernar eminence?
reoccurant nerve a branch of median nerve
what innervates the abductor pollicis brevis?
reoccurant median nerve
what two nerves innervate the flexor pollicis brevis?
superifical head- reoccurant median nerve
deep head- deep ulnar nerve since its in the median side of the hand
what muscle is deep to abductor pollicis brevis?
opponens pollicis
what innervates the opponens pollicis?
reoccurant median nerve
where is the adductor pollicis?
not in the thenar eminence. its in the webbing in the thumb
what are the two heads of adductor pollicis? and attachment?
transverse head- head of 3rd metacarpal
oblique head- to capitiate
what innervates the adductor pollicis?
deep ulnar nerve
what opening does the ulnar nerve enter the hand?
Guyon’s canal
what does the ulnar nerve split into after entering the hand?
deep and superficial branch
what part of the hand does the deep ulnar nerve innervate?
hypothenar muscles
what does the deep ulnar nerve continue to innervate after the hypothernar muscles, sweeping laterally?
3 out of 3 palmar interossei
4 out of 4 dorsal interossei
2 out of 4 lumbricals
what sweeps in the palmar part of the hand with the deep ulnar nerve?
the ulnar artery
what muscles are you using when holding something in between the 1st and 2nd digits?
adductor pollicus
what muscles are you using when the adductor pollicus can’t manage to hold something with the 1st and 2nd digit, it compensates for the adductor pollicus?
flexor pollicus brevis and flexor pollicus longus
what is the test for thumb adduction? and what nerve could be the cause of lacking thumb adduction?
Froment’s sign
Deep ulnar nerve damage
what are the 2 muscles that do thumb and index grip? and what is it’s innervations?
adductor pollicus- deep ulnar nerve
flexor pollicus brevis/longus- median nerve
where will you find the short muscles in the hand?
in between the metacarpals
both dorsal and palmar interossei muscles of the short muscles are located where?
both are anterior in the hand even though its called dorsal interossei muscle
how many dorsal interossei muscles are there and where are they located?
4
first one in between 1st and 2nd digit and so on until the 4th and 5th digit all on the dorsal side?
what is between the 1st and 2nd digit on the palmar/anterior side opposite of the 1st dorsal interossei muscle?
adductor pollicus
what will the dorsal interossei muscle do?
abduct (DAB) the metacarpals
flex at the metacarpal phalangeal joints
extend at the interphalangeal joints (distal and proximal)
where do the dorsal interossei short muscles attach?
originate in between metacarpal dorsally
into
lateral bands of the extensor hood
what are all dorsal interossei muscles innervated by?
deep ulnar nerve
what are the two abductors of the thumb?
abductor pollicus longus and abductor pollicus brevis
where are the palmar interossei muscles?
in the anterior aspect of the hand, its deep to the long finger flexor muscles. in between the metacarpal of the palmar side in between the 2, 3, 4, 5th metacarpals
what is the function of the palmar interossie muscles?
Adduct the metacarpals (PAD)
flex at metacarpal phalangeal joints
extend at PIP and DIP joints
what are the attachments of the palmar interossie muscles?
the same as dorsal interossie muscles:
in between the metacarpals and inserts into lateral bands of the extensor hood
what are the palmar interossie muscles innervated by?
deep ulnar nerve also
what are the attachments of lumbricals?
originate at the lateral aspects of flexor digitorum profundus and inserts at the lateral bands of the extensor hoods
what innervates the lumbricals?
(medial 2) 3rd and 4th- deep ulnar nerve
(lateral 2) 1st and 2nd- digital branch of median nerve
what innervates the flexor digitorum profundus?
medially- deep ulnar nerve
laterally- median nerve
what does the lumbricals do?
they create lumbrical grip
what is the lumbrical grip?
with the action of dorsal/palmar interossie and lumbricals they
flex MCP
extension PIP and DIP
what is lumbrical grip used in clinically?
percussion of the internal organs
what are the extrinsic muscles of the palmar hand?
Flexor digitorum superficialis
and
Flexor digitorum profundus
How are they FDS and FDP traveling in the hand?
in the same synovial sheath
how is the the synovial sheath layed out?
in the digits 2-5 share the same. and digit 1 has its own. therefore it can communicate an infection in the same synovial sheath
what are the two ligament like structures that cover the extrinsic finger muscles?
tethers the FDS and FDP tethered to the digits by annular and cruciform pulleys
how many annular and cruciform pulleys are there?
3- cruciform pulley
5- annular pulley
what is the function of the pulley system in the fingers?
prevents bow-stringing by holding the tendons in place and displacing the force to a different location.
What is the trigger finger?
an issue with a finger pulley, and the tendon gets stuck in the pulley. fixed by cutting the pulley that is affecting the tendon. most effected is a3 or a4
what is the campers chiasm?
flexor digitorum superficialis tendon becomes deep to attach to bone while flexor digitorum profundus tendon is now more superifical due to it continuing to the distal phalangi.
what does the FDS tendon do in the middle phalange?
split and insert on the middle phalange bone
what does the FDP tendon do in the finger distally?
attaches to the distal portion of the distal phalange becoming more superfiicial to FDS by default
what are the extensor muscles of the phalanges?
extensor digitorum extensor digiti minimi extensor indicies lumbercles dorsal/palmar interossie
How does the finger extension occur?
Extensor hood-
How does the extensor hood work?
a central tendon from the inserts just distal to the PIP. emerging from the central tendon two lateral bands(from each side of middle phalange loops and meets at the Distal phalange) looks like leaflet of a branch
what forms the central tendon originate from? HINT: muscles
extensor indicie
extensor digitorum
extensor digiti minimi
what are the three groups of muscles that are in the lateral band of the extensor hood?
dorsal interossie
palmar interossie
lumbricals
what happens when the lateral bands are under tensions?
the IP joints extend
how does the lumbricals, DI, and PI orient prior the metacarpal- phalangeal joint , at MCP joint, and post the MCP joint?
prior- is in the palmar side
at MCP joint- it begins to cross posteriorly
post- it now becomes posterior
due to the extensor hood and the three anterior finger muscles (lumbrical, Dorsal interossie, palmar interossie) what action does it cause
since at the MCP joint these muscles goes from anterior to dorsal side. its action is flexion at MCP joint and extension past the MCP joint
what is the important nerve for digit extension?
Deep ulnar nerve because it innervates the Dorsal interossie, palmar interossie, and the two medial lumbricles
what occurs when the deep ulnar nerve is damaged?
the fingers are stuck in flexion aka Claw hand
what muscles are involved in finger extension?
extensor digitorum
dorsal interossie
palmar interossie
two medial lumbricles
what makes the hand do lumbricle grip. then to full extension.
the intrinsic muscles: DI, PI, and 2 Med. lumbricles bring the fingers to lumbricle grip position. then for full extension you need the extensor digitorum
Thoracic Outlet?
compression of brachial plexus/axillary artery/subclavian artery as it emerges. either by scalenes (roots), by clavicle, pectoralis minor
Pronator teres syndrome?
compression of median nerve by pronator teres
Cubital tunnel syndrome?
compression of ulnar nerve- palmar/dorsal of lateral hand
Radial Tunnel syndrome
anterior portion of lateral epicondyle. loss of sensation of dorsal lateral hand. loss/weak motor of all extensors
what will result form pronator teres syndrome?
loss of motor skill to flexion of the wrist, some pronation loss, loss of sensation of lateral aspect of the palm/finger and tips of the fingers, and weakness in thernar eminence
Carpal tunnel syndrome?
compression of median nerve
what results of carpal tunnel syndrome?
no motor issues on the wrist. weakness of thenar eminence due to reoccurant nerve. parasthesia of just the digits. palmar sparing aka palm is okay.
prolonged medial nerve damage results in what?
ape hand- flattening of thenar eminence. due to the reoccurant median nerve being atrophied
where will cubital tunnel syndrome person complain of?
complain of parathysia palmar and dorsal aspect of the medial hand.
what muscles are effected by carpal tunnel syndrome?
(medial) flexor digitorum profundus flexor carpi ulnaris medial 2 lumbricles DI PI muscles of the hypothenar eminence
how does cubital tunnel syndrome differ from damage at the level of guyons canal?
palmar/ dorsal cutaneous aspect of the ulnar nerve, flexor digitorum profundus, flexor carpi ulnaris not effected. parathysia of 4th and 5th digit (medial)
Posterior interosseous syndrome?
emerges at the level of supinator. with purely motor related. motor of all extensors
Sign of Benediction?
long median nerve compression. results in flat thenar eminence and more. with digits 1, 2, 3 locked in extension due to not being able to flex (flexor digitorum superficialis, flexor digitorum profundus, flexor pollicus longus, all the thenar eminence). not effecting the digits 4 and 5 due to being only by the ulnar nerve
Ulnar claw?
long ulnar nerve lesion. results in hyper extension at the MCP of digits 2-5 and complete Interphalangeal flexion at digits 4-5 and partial interphalangeal flexion at 2-3 digits. doesn’t effect 1st digit (bc its related to median nerve)
what muscles are effected in ulnar claw?
median lumbricles, DI, PI
why does ulnar claw result in hyper extension at MCP?
bc extensor digitorum does reach the distal phalanges
Full claw hand?
both median and ulnar nerve are damaged
what does the hand look like in full claw hand?
1st digit is locked in extension and abduction. MCP is locked in extension. IP are locked in flexion
Erb’s and Klumpke’s Palsy
seen most to infant at birth due to the pull of brachial plexus (roots/trunks). also occurs in adults in severe trauma to the neck/axillary area. Erb’s(C5, C6, maybe C7) Klumpke’s (C8, T1)
If C5 is involved where would you see weakness and parathysia?
parathysia- lateral shoulder
weakness- shoulder abduction
If C6 is involved where would you see weakness and parathysia?
parathysia- lateral forearm into the thumb
weakness- elbow flexion and wrist extension
If C7 is involved where would you see weakness and parathysia?
parathysia- midline of UE to the 3rd digit
motor- elbow extension and wrist flexion
If C8 is involved where would you see weakness and parathysia?
motor- extension of the thumb
parathysia- medial hand and forearm
If T1 is involved where would you see weakness and parathysia?
motor- intrinsic of the hand(abd, add, and some flexion)
parathysia- at the level of the cubital fossa
