Lower Limb Trauma Flashcards
What mechanism causes pelvic injury?
Young patients - high energy injury
Older patients - osteoporosis
Name the bones of the pelvis
Sacrum
Ilium
Ischium
Pubic bones
What neuromuscular structures can be damaged in pelvic trauma?
Internal iliac arterial system
Pre-sacral venous plexus
Roots and branches of lumbo-sacral plexus
Name four types of pelvic fracture
- lateral compression fracture
- anteroposterior compression fracture
- vertical shear
- acetabular fracture
How does a lateral compression fracture occur?
Side impact - one half of the pelvis is displaced medially
Describe the three types of lateral compression fracture
I - ramus fracture and ipsilateral anterior sacral compression fracture
II - ramus fracture and ipsilateral posterior ilium fracture
III - ipsilateral lateral compression and contralateral APCF
How does an anteroposterior compression fracture occur?
Open book fracture due to widespread disruption of the pubic symphysis
Describe the three types of anteroposterior compression fracture
I - symphysis widening <2.5cm
II - symphysis widening >2.5cm, anterior SI d’astasies and disruption of sacrspinous/tuberous ligaments
III - SI dislocation, disruption to sacrospinous and sacrouberous ligaments
Describe a vertical shear fracture
Posterior and superior hemipelvis displacement, high risk of nerve injury and haemorrhage. Shorter leg on affected side
How are pelvic fractures managed?
Pelvic binder to temporarily hold reduction
PR exam
Angiogram
Embolisation or packing of the pelvis
How are acetabular fractures managed?
X-ray/CT
Small/undisplaced - conservative
Displaced/unstable - reduction and fixation or replacement
State the risk factors for hip fractures
- osteoporosis
- smoking
- malnutrition
- excess alcohol
- neurological impairment
- impaired vision
What type of fractures are at risk of non-union?
Intracapsular fractures
How are intracapsular fractures treated?
Fixation, hemiarthroplasty or total hip replacement
Describe garden grading
I - impaction/incomplete
II - non-displaced complete
III - partially displaced
IV - displaced and complete
How will an intracapsular fracture present?
History of fall, painful and unable to weight bear, shortened and externally rotated due to abductors and iliopsoas
Name three types of extra capsular fracture
- basicervical
- intertrochanteric
- subtrochanteric
How are extracapsular fractures investigated?
X-ray
MRI
If an intracapsular fracture is displaced how is it treated?
Poor function - hemi-arthroplasty
Young patient - fixation
Good function - THR
How is an intracapsular non-displaced fracture treated?
Poor function - hemi-arthroplasty
Good function - THR
Good function and good blood supply - fixation
How are extra capsular fractures treated?
Inter-trochanteric - DHS
Sub-trochanteric - Intramedullary nail
Reverse oblique - intramedullary nail
What factors predispose to femoral shaft fractures?
Osteoporosis
Metastatic disease
Paget’s
Long term bisphosphonates
What is the significant complication of femoral shaft fracture?
Substantial blood loss up to 1.5 litres can occur and fat can enter the damaged venous system causing a fat embolism
How is a femoral shaft fracture managed?
Thomas splint
Analgesia
Femoral nerve block
Reduction and stabilisation with nail/plate
How do distal femoral fractures occur?
Osteoporotic bone with a fall onto the flexed knee
Describe a distal femoral fracture
Adopts a flexed position - gastro pull and unless contraindicated fixed with plate, screws and cast
Describe a proximal tibial fracture with valgus stress
Lateral plateau fracture with failure of the MCL and sometimes ACL
Describe a proximal tibial fracture as a result of a blow from car
Proximal fibular fracture and injury to common perineal nerve with foot drop
Describe a proximal tibial fracture due to varus stress
Medial plateau fracture with LCL rupture and stretch injury to common perineal nerve
How are proximal tibial fractures managed?
Total Knee Replacement
Plate and Screws for fixation
What is the most common cause of compartment syndrome?
Tibial Shaft Fracture
How are tibial shaft fractures managed?
Non-operative - above knee cast
Operative - internal fixation controls the position
What is the slowest healing bone in the body?
Tibia
What is a common method of tibial stabilisation?
Intra-medullary nailing
State another name for distal tibial fractures
Pilon fractures
What merits an ankle x-ray?
Tenderness on medial/lateral malleolus if unable to weight bear
Describe a stable ankle fracture
Isolated distal fibular fracture with no other damage is common and treated with a cast/splint for 6 weeks
Describe an unstable ankle fracture
Distal fibular fractures with deltoid ligament rupture - bruising and tenderness
What is talar shift?
Asymmetric increased space around the talus within the ankle mortise
What is talar tilt?
Talus and tibial plafond non-parallel
What bone is commonly fractures on a fall from height onto the heel?
Calcaneal
How does a talar fracture occur?
Forced dorsiflexion from rapid deceleration - risk of AVN if displaced
Reduce and fixation
What is the name for a mid foot fracture?
Lisfranc
What imaging is required for a lisfranc fracture?
CT scan
How will a mid foot fracture present?
Grossly swollen bruised foot upon which they are unable to bear weight
