Hand a wrist Flashcards
Which is the most common bone to fracture is your hand
Scahoid
what percentage of carpal bone fractures does scaphiod fracture make up
70-80%
most common mechanism of action for fracture of a scaphoid bone
fall on a out streached hand
hyperextension and impact of the scaphoid against the rim of the radius
patients with scaphoid fracture complain on
pain in the anatomical stuffbox
pain worsten by moving wrist
swelling around the radial and posterior aspects of the wrsit
fractures in the scaphoid occur in what region of scaphoid
waist of the scahoid (70-80%)
if fractures of the scaphoid do not occur at the waist where will they occur
occur in the proximal pole (20%)
or the distal pole (10%) AKA scaphoid tubercle
a fracture taken immediately after a injury is likely to show how on a x ray
may not reveal fracture
why is late diagnosis of carpal bone fracture common
cant see the fracture on a x-ray until 10-14 days after
why are carpal bone fractures more commonly seen on a x ray 10-14 days after
fracture line may become more visible after some bone reasorption
if still not sure of a scaphoid fracture after 10-14 days x ray what other imaging techniques can you use?
CT or MRI
Descrivbe the blood supple to the proximal pole of the scaphoid
retrograde
tenuous (weak)
fractures through the waist of the scaphoid can cause
avascular necrosis
displacements fractures through the wasit of the scaphoid have high risk of
non-union
malunion
avasualr necrosis
late complications of carpal instability and secondary oestoarthritis
colles’ fracture
an extra articular fracture of the distal radial metaphysis, with dorsal angulation and impaction
what kind of fracture do you also see in 50% of colles fractures
ulnar styloid fracture
colles’ fractures are commonly seen in
people with osteoporosis (reduced bone density)
post- menopausal women
high impact trauma
mechanism of injury for colle’s fracture
fall onto a outstretched hand with a pronated forearm and wrist in dorsiflexion
how patients present with colles’ fracture
painful
deformed
swollen wrist
x ray of colles’ fracture
dorsal angulation and impaction are usually visible on plain x-ray
how to treat colles’s fractrure
reduction and immobilisation in a cast
complications of colles’ fracture healing
malunion median nerve paldy and post traumatic carpal tunnel syndrome secondary osteoarthitis (more common with intra-articular fractures) tear of the extensor pollicis longus tendon (through attrition of the tendon over a shape fragment of bone
Smiths fracture
fracture of the distal radius with palmar angulation of the distal fracture fragment
smiths fractures can be though as the oppostie to
colles’ fracture
mechanism of injury for smith fracture
fall onto a flexed wrist or a direct ow to the back of the wrist
malunion of a smith fracture results in
garden spade deformity
garden spade deformity of the malunion of a smiths fracture can cause what complications think about the nerves in the wrist
narrows and distorts the carpal tunnel and can result in carpal tunnel syndrome
What joints in the hand can get arthritis
metacarpophalangeal joints
interphalangeal joints
Osteoarthsis LOSS
L- LOSS OF JOINT SPACE
O-OSTEOPHYTES
S-SUBCHONDRAL CYTES
S-SUBCHONDRAL SCLEROSIS
Rhumatoid arthritis
L – LOSS OF JOINT SPACE
E- EROSION
S- SOFT TISSUE SWELLING
S-SOFT BONE (OSTEOPENIA)
Rheumatoid arthritis has what kind of distribution
symmetrical polyarthritis
how patients resent with Rheumatoid arthritis
pain and swelling of the PIPs and MCPJ of the fingers
redness overlying the joint
stiffness - worse in moring or after perdios of inactivity
carpal tunnel syndrome (compression of the median nerve in the carpal tunnel, in this case due to synovial swelling)
fatigue and flu like symptoms (due to the systemic nature of rheumatoid disease
adanced rheumatoid arthitisi will present
nodules in the fingers and elbow
advanced deformities
two most common defomaties seen with patients with advanced rheumatoid arthritis
swan neck deformity
boutonniere deformity
what is a swan neck deformity
Poximal interphlangeal joint is hyperextend
Metacarpal phalangeal joint and distal interphlangeal joint is flexed
why is the PIP hyperextensted
there is a imbalance between the muscles froces acting on the PIPJ (extension>flexion))
Describe Boutonniere deformity
the metacarpophalangeal joint and distal interphalangeal joiny are hyperextended
Proximcal interphalngeal joint is flexed
why do you see this shape in boutonniere deformity
immflamtion in the PIP leads to lengthening or ruture of the central slip of extensor digitorum at its inserion into the base of the middle phalanx on the dorsal surface of the finger. the lateral bands slip down the sides of the finger so that they are on the palmar surface and instead od acting as extensors act as flexors. as well as hyperextendinf the Distal interphalangeal joint
Psoriatic arthropathy apprence
skin condition causes red,flaky patches of skin covered with silvery scales
typical locations of psoriatic arthopathy
elbows,knees,scalp and lower back
psoriatic arthopathy can lead to
arthritis
which joints are most effected by psoriatic arthritis
DIPJ
Joint in hand most commonly effected by osteoarthitis is
1st carpometacarpal joint (between the trapezium and the first metacarpal)
osteoarthisis of the 1st CMC joint complaints
pain at the base of their thumb
pain is exacerbated by movement and relieved by rest
stiffness following periods od rest (in the mornings)
swelling aroun the base of the thumb
later stages of 1st CMC joint oestoarthitisis you will see
frist metacarpal subluxes in an ulnar direction, resulting in loss of normal contour and squaring of the hand
heberden’s nodes are a classic sign of
osteoarthitis and effect the Distal interphalangeal joint
herberden’s nodes begin with either two mechanism
chronic swelling of the affected joints or
sudden onset of pain,swelling and loss of manual dexterity
heberden’s nodes typicall start with swelling containing what
gelatinous hyaluronic acid
where about do heberden’s nodes appear on DIP joint
dorsolateral aspect
whats a bouchards node’s
same as a herberden’s but occurs in PIPJs
carpal tunnel syndrome compression of what nerve
MEDIAN NERVE
Wrist factors for carpal tunnel
obesity, repetitive wrist work, pregnancy, rheumatoid arthritis and hypothrodism
what nerve compression may result in
ischaemia, focal demyelination, decrease in axonal calibre and eventually axonal loss
patients complaients with carpal tunnel syndrome
paraesthesia in the dsitrutio of the median nerve (thumb, index finger, middle finger, radial half of ring finger)
worse at night went the wrist drifts into flexon during sleep, narrowing the carpal tunnel further
with carpal tunnel syndrome the sensation to the palm is spaed, why
palmar cutaneous branch of the median nerve branches proximal to the carpal tunnel and passes superficial to it into the palm (so is not compressed)
long term carpal tunnel can result in thenar muscle atropy why
motero branch of the median nerve to the thenar musce exists the median nerve distal to the carpal tunnel
which mucles make up thenar
flexor pollicis brevis (superficial head)
abductor pollicis brevis
opponens pollicis
what motion can the pollicis do in thenar atrophy
flex - flexor pollicis longus is innervated by the anterior interosseous branch of the median nerve in the forearm,
deep head of the flexor pollicis bervis is innervated by the ulnar nerve
Adduction - adductor pollicis is supplied by the ulnar nerve
what canal does ulnar nerve eater wrist though
Guyan’s canal
ulnar tunnel syndrome patients report
paraethesai in the ring and little finger
progression to weakness of the intrinsic muscles of the hand suppled by the ulnar nerve
what muscles in hard are suppled by the ulnar nerve
adductor pollicis
palmar and doral interossei
lumbricals (ring to little finger(
deep head of flexor pollicis berves
Dupuytren’s contracture
loacliased thickening and contracture of the palmar aponeurosis leading to a flexor deformity of the adjacent finger
earl on patients with dupuytren’s contracture notice
thickening in their palm
whats leads to the contracture kater in duputrens contracture
myofibroblasts within the nodule contract leading to the formation of tight bands called cords in the palmar fascia
overlying skin tighly adherent to the palmar aponerosis
fingers becomes stuck in a flexed position and cannot be passively strightened
Dupuytrens contracture inherentence
autosomal dominant 70%
sporadic 30%
common age to get dupuytrens contracture
40 -60 years old common in males
Conditions that increase the risk of developing Dupuytren’s contracture
type 1 diabetis
smoking
heart disease
HIV
Where is a common location to damage the radial nerve
spinal groove of humerus
why is the radial nerve likely to be damaged in a shaft fracture
closely associated with the bone
radial nerve damnage can patients still extend their elbow
yes
extension will be normal or midly compromised
the never head to the long and medial heads of the tricepts is given off prior to the radial nerve entering the spinal groove
the nerve supplying to the lateral head of the tricept is given off in the spiral groove, but this is generally proximal to the fracture and is unaffected
anconeus is paralysed but this has only a minor role in elbow extention
whyc muscle is paralysed in elbow extenion if radial nerve damage
Anconeus
radial nerve damage effected wrist how
wrsit and fingers flexed (wrsit drop)
paralysis of brachioradialis and all extensors muscles of the wrist and fingers
the wrist and finger are flexed when the forearm is pronated because of unopposed flexor muscles and gravity
radial never damage distribution of sensory impairment
posterior cutaeous nerve of the arm branch if radial nerve is unaffected
the lower lateral cutaneous nerve of the arm and psoteior cutaeous never of the forearm branch high in the spinal groove and unaffected
Paraesthsia is therefore usually in the distrution of the superficial branch of the radial nerve
the median nerve gives off no muscular branches to the muscles of the arm therefore supplies
pronator teres, flexor carpi radialis, palmaris longus and flexor digitorum superficialis
(all originate from the medial epicondyle)
what kind of injuty could damage the median nerve in arm
supracondylar fracture of the humerus
median nerve injury above elbow results in loss of what mucles
in antrior foearm both pronators are weak and the flexors of the wrsit are paralysed
except flexor carpi ulnaris and the ulnar hald of the flexor digitorum profundus (supplied by ulnar nerve)
median nerve injury above elbow resulrs forearm in what direction
supinated
due to the unopposed action of supinator and bicep brachii
wrist is flexed in median nerve damage due to
pull of flexor carpi ulnaris
median nerve damage effecting thumb
flexon of thumb is weak or absent as flexor pollicis longus is paralysed but the deep head of the flexor pollicul breve may have some residual innervation from the ulnar nerve
median nerve damnage which fingers effected
index and middle fingers
median nerve damage what happens when they try and make a fist
Hand on benediction index and middle finger stay straight
Ape hand deformity
seen in medial nerve damanage, deformity with the thenar wasting in a high median nerve lesion
above elbow median nerve damage loss of sensory to what region
palm, and 3 and a half digits
back of hand top of index and middle finger
injury to the median nerve at the wrist (low median nerve injury) mechanism of injury
compression carpal tunnel
penetrating injury - broken glass
what muscles are intact in a lower median nerve injury compared to a higher median nerve injury
muscles of common flexor origin at the medial epicondyle
pronator teres, flexor carpi radialis, palmaris longus and flexor digitorium superficialis
and flexor digitorium produndus
muscles paralysed in lower median nerve damanage
LOAF
L lumbricals to the index and middle fingers
O opponens pollicis
A abductor pollicis brevis
F flexor pollicis brevis (superficial head)
what muscles does the ulnar nerve supply in arm
THE ULNAR NERVE DOES NOT SUPPLY ANY MUSCLES IN THE ARM
the ulnar nerve at the level of the elbow gives off a branch to
flexor carpi ulnaris which originates from the common flexor origin on the medial epicondyle and from the ulna
where does the ulnar nerve supple in the forearm
ulnar half of flexor digitorum prfundus (to the ring and little fingers)
and palmar cutaneous branch and doral cutaneous branch
these functions will be intact in a low ulnar injury at the level of the wrist
ulnar nerve supplies what in hand
muscles of the hypothenar eminence, adductor pollicis and the deep head of flexor pollicis brevis , interossei the lumbricals to the ring and little finger, palmaris brevis and palmar digital branches to the ulnar 1 and half digits
if nerve damnaged at wrist lose all these fucntions
what shape hand can long term dmange to ulnar nerve cause
claw hand
fingers hyper extended and MCP and flexed at both the PIP and DIP
Why are the MCPJs of the ring and little finger hyperextended and the IPJs flexed
3rd and 4rd lumbrical muscles supplied by ulnar nerve and paralysed
lumbricals allow what movement
flex the digits at the MCPJ and extend the digits at the IPJ via the dorsal extensor expansion
ulnar claw MCPJs hyperextended why
unopposed extension from the extensor digitorum in the posterior compartmebt of the forearm
ulnar calw PIP and DIP flexed why
unapposed flexion from the flexor muscles in the anterior compartment of the arm
ulnar nerve lesion at wrsit cause loss of sensation
palmar aspect of the ulnar 1 and half digits and the dorsum over the distal phalanges only
injury to the ulanr nerve at the elbow mechanism of injury
medial epicondylar fracture
compression in the cubital tunnel
what muscles lost is ulnar nerve drainage at elbow
muscles of the hypothenar eminence, adductor pollicis and the deep head of flexor pollicis brevis , interossei the lumbricals to the ring and little finger, palmaris brevis and palmar digital branches to the ulnar 1 and half digits
PLUS
flexor carpi ulnarsi, ulnar half od flexoe digitorum profuncuds (to ring and little finger) and loss of sensation in the dorsal and palmar cutaneous branches
is the ulanr claw more or less pronodced in elbow damange
less pronocuded but more muscles dmanged
Ulnar paradox
ulnar claw will be present bu as flexor giditorium profunduc is paralysed there will not be any flexion at the DIPJ of the ring and little finger
