Wrist and Hand Flashcards
what are the different types of distal radius fracture and what type is most common
Smith’s, Colles, Barton’s fractures
Colles fracture is most common
what is the main mechanism of distal radius fractures and who is at highest risk
FOOSH is the main mechanism
elderly people/people with osteoporosis are at a higher risk
describe a Colles fracture
extra-articular fracture of the distal radius with dorsal angulation and dorsal displacement
describe a Smith’s fracture
extra-articular fracture of the distal radius with volar angulation (opposite to Colles’)
occurs when someone falls backwards and puts their hand out to stop them
describe a Barton’s fracture
intra-articular fracture of the distal radius with associated dislocation of the radiocarpal joint (either volar or dorsal)
what distinguishes a bartons fracture from a smith or colles fracture
Barton’s fracture is intra-articular
whereas Smith and Colles are both extra-articular
risk factors for distal radius fractures
risk factors relating to osteoporosis;
- female gender
- increasing age
- prolonged steroid use
- smoking or alcohol excess
- early menopause
what signs can you do that test the function of the 3 nerves in the hand
okay sign (index and thumb opposition) - median nerve (anterior interosseous nerve)
Thumbs up (thumb extension) - radial nerve
Frogment’s sign (adduction of the thumb) - ulnar nerve
management of distal radial fractures
Conservative:
resus and stabilise
all displaced fractures require closed reduction under anaesthetic
following reduction - stable and successfully reduced fractures should be placed in a below elbow backslab cast
physiotherapy
Surgical:
significantly displaced or unstable fractures require surgical intervention, also intra-articular fractures require the same
options include; ORIF with plating or K wire fixation
patient then placed in cast to ensure immobility
what is the most common carpus bone of the wrist to be fractured
scaphoid
describe the blood supply of the scaphoid bone and why its important
supplied by branches of the radial artery - dorsal and volar branch
dorsal branch supplies 80% of the blood and enters the scaphoid distally before travelling in a retrograde fashion towards the proximal end
consequently fractures of the scaphoid can result in avascular necrosis and subsequent degenerative wrist disease
the more proximal the fracture the higher the risk of AVN
management of a scaphoid fracture
conservative; undisplaced fractures not involving the proximal pole of the scaphoid require strict immobilisation in a plaster
surgical; displaced fractures fixed operatively using a percutaneous variable-pitched screw
what is the main important complication of scaphoid fractures
risk of avascular necrosis
if a patient has had 2 negative x-rays of the wrist but is still showing clinical signs of a scaphoid fracture what are the next steps
place in interim cast and immobilise
MRI of wrist
what is the main artery that supplies blood to the scaphoid
dorsal branch of the radial artery
what is carpal tunnel syndrome
condition involving compression of the median nerve within the carpal tunnel of the wrist
what nerve is affected in carpal tunnel syndrome and what symptoms does this induce
median nerve
pain, numbness and paresthesia in the lateral 3.5 digits
risk factors for carpal tunnel syndrome
obesity, female gender, increasing age, previous injury to wrist, repetitive hand or wrist movements
also associated with diabetes, rheumatoid and hypothyroidism
why is the palm often spared (no symptoms) in carpal tunnel syndrome
because the sensory supply to the palm (palmar cutaneous branch of the median nerve) branches proximal to the flexor retinaculum passing over the carpal tunnel
what tendon creates the carpal tunnel by running superiorly from the pisiform to the scaphoid
flexor retinaculum (transverse carpal ligament)
sign of later stage carpal tunnel syndrome
weakness in thumb abduction/wasting of thenar eminence due to denervation atrophy of the thenar muscles
management of carpal tunnel syndrome
conservative; wrist splint (preventing flexion), physiotherapy, corticosteroid injections
surgical; carpal tunnel release surgery - decompress the carpal tunnel by cutting through the flexor retinaculum, reducing the pressure on the median nerve
what is a Dupuytrens contracture
condition involving the contraction of the longitudinal palmar fascia
develops at the MCP and interphalangeal joints and can severely limit digital movement and reduce patients quality of life
describe the pathophysiology and disease progression of a dupuytrens contracture
thickening and contraction of the plantar fascia
- initial pitting and thickening of the palmar skin and underlying subcut tissue, with loss of mobility of overlying skin
- firm painless nodule begins to form, becoming fixed to the skin and the deeper fascia, gradually increasing
- cord then develops, resembling a tendon, which begins to contract over months to years
- contraction of the cord pulls on the MCP and PIP joints, leading to progressive flexion deformity in the fingers
