The hand Flashcards
Which bones articulate with the carpals distally
Metacarpals
Metacarpals are numbered… which is first
First is nearest to the thumb (so actually the lateral one is 1st in the anatomyical psoiton)
What bones do the metacarpals articulate iwth
The proximal phalanges, thne middle phalanges then distal phalanges
What is the palmar aponeurosis- what is it continuous proximally and distally
Proximal- continuous with flexor retinuaculum (which the palmaris longus tendon attaches to)….
distally is it fibrous digital sheath
What underlies the palmar aponeurosis and what is contained within fibrous digital sheaths
palmar aponeurosius overlies the long flexor tendons of the hand (FDS/FDP)
Fibrous digital sheaths
contain the flexor tendons and their synovial sheaths
How does the FDP relate to the FDS in the proximal digit
FDP on theinside, FDS outside… both surrounded by the synovidal sheath/fibrous digit sheath…. superifical to the prox. phalanx
Where does the extensor expansion lie with respect to the phalanx
Deep (entensor dorsal expansion)
There are 2 fibrous septa of the palm, what are these and where are they
Medial septum: between the palmar aponeurosis and the 5st metacarpal
Lateral septum: from palmar aponeurosis to the 3rd metacarpal
State the compartments of the hand
Hypothenar compartment
Central compartment
Thenar compartment
Adductor compartment
On the surface of the hand, which lies more medial, thenar or midpalmar
and which septum divides the thenar and midpalmar space
thenar space
lateral septum divides
Where in the hand are the following:
Thena compartment, central compartment, Adductor compartment Thenar space Hyppothenar compartment Hypothenar fascia
Thenar is proximal to the thumb
Central is underneath the palmar aponeurosis in middle of palm
Adductor is deep to the thenar
Thenar space occurs between the thenar, central and adductor component
Hypothenar is near the little finger
Hypothenar fascia is medial to the hypothenar compartment
Name the categories of intrinsic muscles of the hand
thenar compartment
adductor compartment
hypothenar compartment
interossei and lumbricals
State the INTRINSIC thenar muscles
State the INTRINSIC adductor muscles
State the INTRINSIC hypothenar muscles
State the INTRINSIC interossei and lumbricals muscles
THENAR:
- abductor pollicis brevis
- flexor pollicis brevis
- opponens pollicis
ADDUCTOR:
-adductor pollicis
Hypothenar muscles:
- abductor digiti minimi
- flexor digiti minimi
- opponens digiti minimi
Interossei and lumbricals:
lumbricals – flex the MCP’s (metacarpalphalyngeal joints), extend the IPJs (interphalyngeal joints)
palmar interossei – adduct the digits (“PAD”)
dorsal interossei – abduct the digits (“DAB”)
Where is the opponens pollicis
The anterior part of hand below thumb….. opposition is bringing thumb towards little finger
Look at the diagram of tumb movements
…
Which muscles abduct the thumb
APL (not intrinsic hand muscle), APB
Which muscles adduct the thumb
Adductor pollicis, first dorsal interosseous
both intrinsic hand muscles
Which muscles extend the thumb
EPL, EPB, APL
none are intrinsic hand muscles
Whichmuscles flex the thumb
FPL (not an intrinsic hand muscle), FPB
Which muscle(s) cause opposition of thumb
Opponens pollicis
T/f lumbricals are superifical to the interossei
t
Where is te adductor pollicis attached
middle finger proximal phalanx to the middle phalynx of the thumb
What muscle is teh adducotr policis supplied by vs the thenar muscles
Adductor pillicis- ulnar nerve
Thenar muscles- median nerve
How many dorsal interossei, palmar interossei and lumbricals are there
where do the lumbricals originate
where do lumbricals insert
Where is the attachments of the inerossei muscles
Function of each interossei
interossei= 3 palmar interossei= 4 and lumbricals are there=4
from the flexor digitalis profundus…. from tendon not bone!! They come from anterior to posterior
Lumbicals insert into the extensor expansion
Inserted into the base of the proximal phalanx and the extensor expansion
PAD- palmar interossei ADDUCT in relation to the axial line which is down the middle phalanx (all toward the middle phalanx)
DAB- dorsal abduct
2/3 palmar interossei stabilise the middle finger….
look at the attachments
What are the anterior tendons of the hand
Fibrous digital sheath
Osseo-fibrous tunnels
In the tunnels run the long flexor tendons and their synovial sheaths
Annular and cruciform pulleys
Outline how flexor muscles of the digits enter the hand
FDP and FDS pass in the carpal tunnel,
under the flexor retinaculum,
enter common synovial sheath and
enter digital synovial sheath within its own fibrous digital sheath
T/f the flexor of thumb muscles enter the common synovial sheath
f: the FPL do not enter it
T/f the common synovial sheath is continuous with the digital synovial sheath
f: the digital synovial sheath for the little finger is continuous with the common synovial sheath.
The synovial sheath for thumb does not enter the common synovial sheath, so this sheath is just continuous with itself
Outline the structure of the FDS and FDP
FDS splits around FDP
FDS to middle phalanx, FDP to distal phalanx
as FDP supplies the distal phalyngeal joints
Outline the structure of the synovial sheath of the digit
It has two layers (then the fibrous digital sheath on the outside).
These are the synpvial lining of the tunnel (outside) and synovial covering of the tendon (inside)
The space in between these layers is the osseofibrous tunnel
T/F an artery of the digit would run in the osseofibrous tunnel
F… it runs in the medotendon. This is an area where the two layers of the synovial tendon meet, forming vincula
What are vincula
Within each osseo-aponeurotic canal, the tendons of the flexor digitorum superficialis and flexor digitorum profundus are connected to each other, and to the phalanges, by slender, tendinous bands, called vincula tendina
Outline the parts of the fibrous digital sheath
Annular (A1-5 from prox. to dist….. look like rings)
Cruciate (C1-4 from prox to dist…. look like cross)
State the tendons of the posterior hand
Extensor retinaculum Synovial tendon sheaths Inter-tendinous bands Extensor expansions Lumbricals and interossei attach to the expansions Extensor digitorum, EI, EDM
Look at the cross section of the hand….
what is in compartment
1-6
- Abductor pollicis longus and extensor pollicis brevis
- Extensor carpi radialis longus and brevis
- Extensor pollicis longus
- Tendinous sheath for extensor digitorum and extensor indicis
- Extensor digit minimi
- Extensor carpi ulnaris
Joints of the hand region
Distal radio-ulnar joint Wrist joint Intercarpal joints Carpo-metacarpal and inter-metacarpal joints Metacarpo-phalangeal joints Interphalangeal joints
What is the axis of rotation from supination to pronation
A vertical line through the distal radioulnar joint (exactly where the two bones articulate)
The wrist joint
Make notes….
The articular disc between the ulna and the triquetrum/pisiform is comprised of what
The ligamentous border of the articular disc (between the radius and ulna)
and the sacciform recess of the snovial capsule
Outline ligaments in the writ
……
Outline ligaments in the writ
…….
T/F there are two radial extensors and 1 ulnar
T:ECRL, ECRB, ECU
Revision: which muscles would be involved in:
radial deviation
ulnar deviation
Radial: ECRB, ECRL, FCR, APL
Ulnar: FCU, ECU
What are the intercarpal joints
Joints between the proximal row:
scaphoid, lunate, triquetral, pisiform
Joints between the distal row:
trapezium, trapezoid, capitate, hamate
Joints between the proximal and distal rows:
the midcarpal joint
The CMC of the thumb is between which 2 bones
Trapezium –> thumb metacarpl (MC1)
What type of joints are the metacarpals involved in
CMC of thumb and digit (i.e. metacarpal/carpal)
Intercarpal joints
Which movements can occur at the Carpometacarpal and Intermetacarpal Joints (CHECK)
flexion and extension
radial deviation and ulnar deviation
circumduction
What movement can occur at metacarpal-carpal joints
flexion and extension
abduction and adduction
Why is the ulnar collateral ligament of the thumb important\?
Make notes
What movements can happen at the IP joints
Flexion and extension only
What is DIP and PIP
Proximal Interphalangeal PIP
Distal Interphalangeal DIP
T/f thumb has both PIP and DIP
F…. only one interphalangeal joint
What is a volar plate
the palmar ligament
Outline the components of the metacarpo-phalangeal joint
- Collateral ligament (cord-like part and fan-like part)
2. Palmar ligament (volar plates)
What is the extensor expansion and what is it anchored to
pecial connective attachments by which the extensor tendons insert into the phalanges. These flattened tendons (aponeurosis) of extensor muscles span the proximal and middle phalanges….
attach to the PALMAR ligament
Slide 48
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Slide 48
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Where is the ulnar present on the hand
Beside FCU at the wrist
Which arch(es) does the ulnar artery form
Superficial palmar arch – palmar digital arteries
Deep palmar branch
These come from the interosseous arteries in the forearm of the ulnar
Where is the radial artery present
Under brachioradialis and beside FCR at the wrist
+
Anatomical snuff box
What arteries does the radial artery contribute to
Deep palmar arch
Palmar metacarpal arteries
Arteries of hand….
there is anastamosis between the palmar arch and the dorsal carpal arch
Nervous supply of the hand muscles
All by the median nerve apart from the adductor policis, which is supplied by the ulnar nerve
Clinical significance of the synovial sheaths o fthe hand
The flexor pollicis longus has its synovial sheath, which is separate from the common synodival sheath.
As such, infection would not spread to the fingers from the thumb
How does the pisiform join with the ulnar and the distal carpal bones
It doesn’t it is suspended in a tendon and doesn’t interact with the bones
Fuction of each nerve in the forearm
Median nerve
- Main nerve of the anterior compartment of forearm
- Some supply to hand intrinsic muscles
Ulnar nerve
- Main nerve of the hand
- Some of anterior compartment (FCU, half of FDP)
Radial nerve
- Posterior compartment of the forearm
- Some sensory component to the hand
What are the digital nerves
Purely sensory
Often damaged
Median nerve function
Enters the carpal tunnel with FDP, FDS and FPL
Motor to:
Thenar muscles (APB, FPB, OP) and lumbricals I and II
Sensory to:
Palmar surface of thumb, IF, MF and half of RF
Some of the dorsal surface of those digits
Ulnar nerve function
Runs over (not under) the flexor retinaculum, lateral to the pisiform Divides into; Superficial branch, sensory to; palmar surfaces of LF and half of RF Deep branch, motor to; hypothenar muscles adductor pollicis lumbricals III and IV all the interossei
What does the ulnar nerve pass through
The Guyon’s tunnel
Outline the 3 types of grip
- Power Grip
long flexors of the fingers and thumb
intrinsic muscles of the palm
extensors of the wrist joint! - Precision grip
the wrist and fingers are held rigidly by the long flexors and extensors
the intrinsic muscles of the hand carry out the fine movements needed
3.Hook grip
consumes little energy, mainly involves long flexors of digits; e.g. carrying shopping bag or briefcase
How thick is the extensor retinaculum compared tot he flexor retinaculum
NOT as thick and chunk as the flexor retinaculum, but it is able to hold the tendons down.
Outline structure of extensor tendons vs flexor tendons
There are some connections between extensors of digits (i.e. between extensor digitum and extensor digiti minimi too)…
called INTERDENDINOUS CONNCTION
Outline the ligaments of the wrist (not included on the ppt. but fairly simple)
There are four ligaments of note in the wrist joint, one for each side of the joint
Palmar radiocarpal – It is found on the palmar (anterior) side of the hand. It passes from the radius to both rows of carpal bones. Its function, apart from increasing stability, is to ensure that the hand follows the forearm during supination.
Dorsal radiocarpal – It is found on the dorsum (posterior) side of the hand. It passes from the radius to both rows of carpal bones. It contributes to the stability of the wrist, but also ensures that the hand follows the forearm during pronation.
Ulnar collateral – Runs from the ulnar styloid process to the triquetrum and pisiform. Works in union with the other collateral ligament to prevent excessive lateral joint displacement.
Radial collateral – Runs from the radial styloid process to the scaphoid and trapezium. Works in union with the other collateral ligament to prevent excessive lateral joint displacement.
