Hand Trauma

Question 1

what are the four types of injuries associated with the hand?

Answer 1

• avulsion and ligamentous injuries
• impact fractures
• dislocations
• foreign bodies

Question 2

name the two avulsion and ligamentous injuries associated with the hand

Answer 2

• mallett finger
• gamekeeper’s/skier’s thumb

Question 3

name the two impact fractures associated with the hand

Answer 3

• boxer’s fracture
• Bennett’s fracture

Question 4

describe mallett finger

Answer 4

a deformity of the finger caused when the extensor digitorum (tendon that straightens finger) is damaged

Question 5

MOI for mallett finger

Answer 5

• something strikes the tip of the finger and causes ‘forced flexion’ of an extended digit
• this stretches the tendon away from the bone
• can also pull a fragment of bone with it causing an avulsion fracture

Question 6

describe the radiographic appearance of mallett finger

Answer 6

• a fracture fragment is shown at the distal interphalangeal joint
• if there isn’t an avulsion fracture, ligamentous damage still appears

Question 7

describe treatment for mallett finger

Answer 7

• usually non operative
• finger placed in extension and splinted for 6 weeks
• DIP joint kept immobile in extension for 6 weeks
• if fracture fragment is large will require ORIF (open reduction internal fixation) surgery using K-wires

Question 8

describe the prognosis for mallett finger

Answer 8

• when treated immediately prognosis is good and full recovery
• skin ulcerations and nail deformities when healing
• untreated may lead to swan neck deformity and secondary arthritis

Question 9

describe gamekeeper’s/skier’s thumb

Answer 9

tear of the ulnar collateral ligament (UCL) (medial ligament) at the metacarpo-phalangeal joint
gamekeeper’s - chronic
skier’s - acute

Question 10

MOI for gamekeeper’s/skier’s thumb

Answer 10

the ligament can either tear due to a widened MCPJ or the ligament can tear and may pull a fragment of bone resulting in an avulsion fracture

Question 11

describe the radiographic appearance of gamekeeper’s/skier’s thumb

Answer 11

• a fracture fragment can be seen at the insertion of the UCL (base of proximal phalanx)
• or if it is just ligamentous damage then this can be shown due to a widened MCPJ

Question 12

describe treatment for gamekeeper’s/skier’s thumb

Answer 12

• splinting for 6 weeks
• if serious surgery to repair ligament
• surgical fixation with ORIF ligament repair

Question 13

describe the prognosis for gamekeeper’s/skier’s thumb

Answer 13

• treated immediately prognosis is good
• complete tear repaired late can lead to long term weakness and pain
• increased long term arthritis

Question 14

describe boxer’s/scrapper’s fracture

Answer 14

comminuted transverse fracture of
boxer’s - 2nd/3rd metacarpal
scrapper’s - 4th/5th metacarpal

Question 15

MOI for boxer’s/scrapper’s fracture

Answer 15

direct blow with clenched fist against a solid surface
boxer’s - full force with wrist in neutral position
scrapper’s - swinging blow with less force and not as central

Question 16

describe the radiographic appearance for boxer’s/scrapper’s fracture

Answer 16

comminuted transverse fracture to a metacarpal

Question 17

describe treatment for boxer’s/scrapper’s fracture

Answer 17

• closed reduction aligns fragments of the fracture prior to immobilisation
• surgical intervention using k wires or ‘pin and plate’ fixation
• surgical reduction must minimise angulation of the fragments

Question 18

describe Bennett’s fracture

Answer 18

• intra-articular fracture of the base of the first metacarpal with dislocation off the first carpometacarpal joint
• small fragment of metacarpal stays attached to the ligament and articulates with the trapezium

Question 19

MOI for Bennett’s fracture

Answer 19

axial blow on a partially flexed first metacarpal (punch with clenched fist)

Question 20

describe the radiographic appearance of Bennett’s fracture

Answer 20

oblique fracture line at the base of the first metacarpal with a triangular fracture fragment at base of the metacarpal

Question 21

describe treatment for Bennett’s fracture

Answer 21

• minor fractures treated by closed reduction to align fragments
• immobilised in thumb spica for 6 weeks
• allow gradual mobilisation
• more serious require surgical intervention using K wires or ‘pin and plate’ fixation

Question 22

describe prognosis for Bennett’s fracture

Answer 22

prognosis is usually good
complications include:
- osteoarthritis at carpometacarpal joint
- reduced movement at joint
- recurrent joint instability
- skin infections
- radial nerve injury

Question 23

describe finger dislocations

Answer 23

dislocation of a phalanx from its normal anatomical position also the volar plate may rupture associating with an avulsion fracture

Question 24

MOI for finger dislocations

Answer 24

forced hyper extension or flexion of a phalanx
- sporting injury, trapping in door, fall on outstretched hand

Question 25

describe the radiographic appearance of finger dislocations

Answer 25

hyper extension:
phalanx moves posteriorly, fracture fragment may also be visible
hyper flexion:
phalanx moves anteriorly causing a volar dislocation

Question 26

describe treatment of finger dislocations

Answer 26

• closed reduction to align phalanges
• splinting and immobilising for 6 weeks

Question 27

describe prognosis for finger dislocations

Answer 27

good prognosis as long as no entrapment of ligaments during reduction