T&O - wrist and hand Flashcards
Describe this X-Ray
- AP and Lateral X-Ray views (of unknown person taken at unknown time)
- Of the Right wrist and hand
- The most obvious deformity is a extra-articular fracture to the distal radius with dorsal angulation and dorsal displacement consistent with a Colle’s fracture
How does a Smith’s fracture appear on X-ray?
- Extra-articular Distal radius fracture with volar angulation +/- volar displacement
What is a Barton’s fracture?
An intra-capsular fracture of the distal radius with associated dislocation of the radio-carpal joint
What are risk factors for distal radius fractures?
- Mainly related to osteoperosis
- Increasing age
- Female gender
- Early menopause
- Smoking
- Alcohol excess
- Prolonged alcohol missuse
How do you assess the neurovascular supply of the hand following a distal radius fracture?
Median nerve:
- Sensory radial surface of 2nd digit
- Motor abduction of the thumb (anterior iterosseus nerve)
Radial nerve:
- Sensory dorsum of 1st web space
- Motor extension of IPJ of the thumb
Ulnar nerve:
- Sensory ulnar surface of 5th digit
- Motor adduction of the thumb (Frommet’s sign)
What measurements are taken on an X-ray of a distal radius fracture?
- Radial height (<11mm)
- Radial inclination (<22º)
- Radial volar tile (>11 º)
How are distal radius fractues managed?
Mostly conervatively: traction and manipulation under anaesthetic + below elbow backslab cast
Surgery: only required if severely displaced or unstable
What complications can occur after a distal radius fracture?
- Malunion
- Dinner fork deformity in Colle’s fracture if not properly manipulated
- Median nerve compression
- Osteoarthritis
Describe the blood supply to the scaphoid
Branches of the radial artery
a) volar branch
b) dorsal branch - supplies 80% of blood
- enters the distal pole in a retrograde fashion
- The more proximal the scaphoid fracture the high the risk of AVN
What is felt on examination in a scaphoid fracture?
- Sudden onset wrist pain and bruising following trauma
- Tenderness over the anatomic snuffbox
- Pain on palpating the scaphoid tubercle
- Pain on telescoping of the thumb (pulling)
What x-ray views are needed in scaphoid fractures?
- Lateral
- AP
- Oblique
- Knwon as the ‘scaphoid series’
What is the issue with detecting a scaphoid fracture on initial presentation? How do you procede?
- Fractures are not always detected on initial x-ray
- If there is clinical suspicion despite negative imaging then immobilise wrist in a thumb splint and repeat 10-14 days later
- If radiographing is still negative 10-14 days later then do an MRI of the wrist
How are scaphoid fractures managed?
Undisplaced: struct immobilisation under plast with a thumb splint
However, due to high risk of AVN surgery may be advocated especially if it is the patients dominant hand
Displaced: will need surgery - percutaneous variable pitched screw
What are some of the complications of a scaphoid fracture?
- AVN (risk increases the more proximal the fracture)
- Non-union due to poor blood supply
- can be managed with internal fixation and bone grafts
Give the border and contents of the carpal tunnel
What are some risk factors for developing carpal tunnel syndrome?
- Female
- Increasing age
- Pregnancy
- Obesity
- Previous wrist injury
- Diabetes Mellitus
- RA
- Hypothyroidism
- Repetive hand or wrist movements
Descibe the clinical presentation of carpal tunnel syndrome?
- Pain numbness and paraesthesia in median nerves sensory distribution
- palm is often spared as plamar cutaneous branch of median nerve branches before carpal tunnel
- Symptoms typically worse at night
- can be relieved by hanging affected arm out the bed or shaking
- No visible findings on examination
- Tinel’s test (percussing over nerve) and Phalen’s test (wrist in full flexion for 1 minute causes the sesnsory symptoms
- Later stages: may see weakness of thumb abduction or wasting of the thenar eminence
What differential diagnosis should be considered if suspecting carpal tunnel syndrome?
- Cervical Radiculopathy - C6 nerve root compression causes similar paraesthesia distribution but there will be neck pain and involvement of entire arm
- Pronator Teres syndrome - median nerve compression by prontaor teres. Symptoms extend to proximal forearm and palm sesnation is reduced
- Flexor carpi radialis tenosynovitis- causes tenderness at the base of the thumb
How can carpal tunnel syndrome be managed?
- Conservative: wrist splint, preventing wrist flexion, physiotherapy and training exercises
- Corticosteroid injections direct to carpal tunnel
- Trial NSAIDs but little evidence
- Surgery for severely limiting cases
Briefly explain carpal tunnel surgery
- Decompression of the carpal tunnel by cutting through the flexor retinaculum which reduces the pressure on the median nerve
- Can be done under local anaesthetic as a day case
What are some complications of carpal tunnel decompression surgery?
- perisitant CTS symptoms if ligament release is incomplete
- infeciton
- scar
- nerve damage
- trigger thumb
What complication can arise if carapal tunnel is untreated?
Long term CTS can cause permanent neurological impairment
What is Dupuytren’s contracture?
Contraction of the longitudinal palmar fascia, starts as painless nodules then develops fibrous cards and flexion contractures which can severely limit digital movement
Describe the pathophysiology of Dupuytren’s Contracture
Fibroplastic hyperplasia and altered collagen matrix of the palmar fascua leads to thickening and contraction
- Inital pitting and thickening of palmar skin and underlying subcut tissue - there is loss of mobility of overlying skin
- Firm painless nodules begin to form, gradually increasing in size
- Cord develops resmbling a tendon - contracts over months to years
- Contraction of the cord pull on MCP and PIP joints causing progressive flexion deformity in the fingers
