Lower Limb Fractures Flashcards
What is the most common fracture in the elderly population
Femoral neck fracture
- risk increases with age and osteoporosis
Can occur in the young population after a high energy trauma
What are the anatomical classifications of a femoral neck fracture?
Intracapsular fracture
- occur within the joint capsule (proximal to intertrochanteric line)
Extracapsular fracture
- occurs distal to the joint capsule (involving or distal to the trochanteric line)
Why does the site of a femoral fracture matter
Relationship to blood supply
- femoral head receives supple from the femoral neck
- an intracapsular fracture disrupts this blood supply and can cause avascular necrosis
How are intracapsular fractures managed
Usually require surgical intervention to prevent AVN
- undisplaced = internal fixation (DHS)
- displaced = hemiarthroplasty
- total hip arthroplasty is they have symptomatic, pre-existing arthritis, or if the patient is very high functioning (elderly)
- children/young adults can have reduction and fixation
How are extracapsular fractures managed
Only requires closed reduction and open fixation with DHS
What are the complications of a femoral neck fracture
Mortality (20% at 90 days) AVN of femoral head Dislocation of arthroplasty Loss of fixation Non-union Lower limb thromboembolic disease
What are the risk factors for osteoporosis
Steroids Hyperthyroidism Alcohol Thin Testosterone (decrease) Early menopause (female) Renal/liver failure Erosive/inflammatory bone disease e.g. RA Dietary
Family history
Age
What is a T-score
Bone mineral density compared to that of a healthy young adult
- T-score is the number of standard deviations the patients bone mineral density is from average
T-score results meaning
T-score > 0 = BMD better than the reference range
T-score 0 to -1 = no evidence of osteoporosis
T-score -1 to -2.5 = osteopenia, increased risk of osteoporotic fracture
- requires lifestyle advice
T-score
What is the management of femoral neck fracture, post-surgery
Bisphosphonates - reduce risk of recurrence, regardless of BMD
Calcium and vitamin D
Rehab
- fall-prevention assessment (med review, removing hazards in home, assessing muscle strength, balance and gait)
- home/osteoporosis/skilled nursing facilities
- early ambulation
Nutritional concerns need addressing
Periodic X-Ray to assess AVN risk (MRI if unsure)
Two types of pelvic fractures
Low energy insufficiency
High energy fracture
Describe a low energy insufficiency pelvic fracture
Age >60 years
Fall from standing height
Can be displaced, non-displaced and usually involves both the anterior and the posterior pelvis
Describe a high energy pelvic fracture
Age <60 years
Caused by a RTA, fall from height or sports (e.g. horse riding)
- requires a lot of force
Clinical features of a pelvic fracture
Inability to weight bear Pelvic pain Pelvic tenderness Unstable pelvis on palpation Haematuria Haematoma over ipsilateral flank, inguinal ligament, proximal thigh or perineum Lower limb neurovascular deficits - PR for tone and sensation Rectal bleeding Instability and pain on hip adduction - indicates acetabular fracture PR and vaginal exam to assess occult fracture
Initial management of pelvic fracture
ABCDE X-Ray - anterior-posterior - inlet - occult CT - for posterior pelvic structures
Management of a stable (single ring) pelvic fracture
Bed rest
Analgesia
Early mobilisation
Management of an unstable (multiple ring) pelvic fracture
Liable to massive haemorrhage
- due to tearing of posterior presacral venous plexus
ABCDE
Establish haemodynamic control
- fluid resuscitation
- X-match/O negative blood if needed
- pelvic binder for external hemorrhage control
Refer to orthopaedics
- external fixation followed by ORIF/screw fixation
Why are hip dislocations a surgical emergency
Damage to local nerves and blood vessels occurs as the femoral head is forced from the socket
- typically requires an extreme amount of force
- damage to blood vessels: AVN
- damage to nerves: sciatic nerve damage
Posterior dislocation (90%) or anterior dislocation (10%)
Why is a knee dislocation a surgical emergency
High rate of vascular injury - in both high and low impact cases
- assess limb perfusion (may require emergency vascular repair and fasciotomy)
- peroneal nerve injury
Common causes of femoral fractures
High energy in young people
- RTA
- fall from height
Why can a femoral fracture be an emergency
Association with major haemorrhage
- 1000-1500mls of blood can be lost into the femoral shaft (closed
- double that if open
Emergency management - femoral fracture
ABCDE
Haemodynamic control - IV fluids, bloods (X-match)
Realign fracture and Thomas splint leg
- control pain and haemorrhage to allow X-Ray to be taken
External fixation - used in damage control scenarios and replaced at a later date
Full secondary survey
Operative management - femoral fracture
Locked and reamed intramedullary nailing to provide rotational stability
Plate and screw- if ipsilateral NOF #
Traction splint if too sick for surgery
Tibial fracture - complications
Compartment syndrome
- can occur in open and closed
- higher risk when lower leg damaged (vs thigh)
Mal/non-union
Knee pain
Malrotation
Nerve injury (during operative management)
Tibial fracture - emergency management of open fracture
ABCDE Fracture reduction Assess neurovascular status Normal management of open fracture - IV antibiotics, photo, remove gross contamination, tetanus vaccine, application of saline soaked gauze and immobilisation with splint
Ankle fracture-dislocation - emergency management
Immediate closed reduction and backslab before X-Ray
- due to risk to blood vessels and nerves
- check neurovascular status before and after
Ankle fracture-dislocation - management of a stable injury
Lateral malleolus with no talar displacement
- Weber A/B
Below-knee cast for 6 weeks
- post-cast X-Ray needed to check position
- allows weight-bearing
Ankle fracture-dislocation - management of an unstable injury
Minimal displacement (2mm or less)
- acceptable in the elderly, treated as a stable fracture
Weber B/C fracture with medial tenderness or talar shift
- ORIF
- post-op cast (non-weight bearing for 6 weeks as fracture heals)
Ankle fracture - most common type
Distal fibula fracture (and pilon)
Metatarsal bone - fracture patterns
Avulsion fracture of 5th metatarsal
- twisting injuries (inversion)
- causes avulsion of the proximal tuberosity
Metatarsal shaft fractures
- diaphyseal, metaphyseal
- caused by crush injuries (car running over foot)
- less common
Lisfranc injury
Disruption of articulation between the medial cuneiform and base of the second metatarsal
- high energy fracture pattern
- also causes incongruity between 2nd metatarsal and intermediate cuneiform (TMT joint)
