Pelvis and Lower Limb trauma

Question 1

who gets pelvic fractures?

Answer 1

young people - usually dur to high energy
older people - usually due to osteoporosis - can get pubic rain fractures from low energy injuries, usually minimally displaced lateral compression injuries and settle with conservative management over time

Question 2

what forms the pelvic ring?

Answer 2

sacrum
ilium
ischium
pubic bines with strong supporting ligaments

Question 3

vessels of the pelvic ring

Answer 3

branches of the internal iliac arterial system and the pre0sacral venous plexus are prone to injury
risk of serious hypovolaemia

Question 4

nerves of the pelvic ring

Answer 4

nerve roots and branches of the lumbosacral plexus are prone to injury

Question 5

lateral compression fracture in the pelvic ring?

Answer 5

due to side impact (RTA) where 1 half of the pelvis (hemipelvis) is displaced medially
fractures through the pubic rami/ischium involve a sacral compression fracture of SI joint disruption

Question 6

vertical shear fracture in the pelvic ring?

Answer 6

due to axial force on one hemipelvis (e.g. fall from height, rapid, deceleration)
affected hemipelvis is displaced superiorly
risk of injury to the sacral nerve roots and lumbosacral plexus
risk of major haemorrhage
leg on the affected side will appear shorter

Question 7

anteroposterior compression injury in the pelvic ring?

Answer 7

can cause wide disruption of the pubic symphysis
resulting in an ‘open-book pelvic fracture’
causes substantial bleeding from torn vessels
also from the pelvic volume increasing exponentially due to the degree of displacement - with widely displaced injuries the pelvis can hold several litres of blood before tamponade and clotting occur

Question 8

management of pelvic ring fractures

Answer 8

prompt assessment and resuscitation

treat the blood loss - fluids/blood

Question 9

management of open book pelvic fractures

Answer 9

promptly reduce the displacement to minimise the pelvic volume to allow tamponade of bleeding to occur
apply tied sheet/special pelvic binder around the outside of the pelvis to hold the reduction temporarily and allow slotting of the vessels
an external fixator will provide more secure initial stablisation

Question 10

what is the management if after initial pelvic fracture management haemodynamic instability continues

Answer 10

angiogram and
embolisation,
or open packing of the pelvis if laparotomy is required for co-existing intra-abdominal injuries

Question 11

what are the other structures which can be injured in a pelvic fracture?

Answer 11

potential for bladder and urethral injuries, blood at the urethral meatus and urinary catheterisation can cause further injury
urological assessment and intervention is needed

Question 12

what exam is mandatory when there is pelvic fracture?

Answer 12

PR exam to assess sacral nerve root function and to look for blood
presence of blood indicates a rectal tear injury - the injury is an open fracture with a higher mortality risk
general surgical review as may need defunctioning colostomy

Question 13

What is the acetabulum?

Answer 13

intra-articular section of the pelvis which forms the ‘cup’ of the hip joint

Question 14

who gets acetabulum fractures?

Answer 14

younger patients with high energy injuries

older patients with low energy injuries

Question 15

what is the significance of posterior wall acetabulum fractures/

Answer 15

may be associated with hip dislocation - head of femur pushed out the back of the joint - RTA where the car driver’s knees collide with the dashboard

Question 16

how is a acetabulum fracture investigated?

Answer 16

x-ray (difficult to see - try oblique view)

CT scans - determine fracture pattern for surgical planning)

Question 17

how are undisplaced/small wall acetabulum fractures managed?

Answer 17

conservative management

Question 18

how are intra-articular/unstable/displaced acetabulum fractures managed?

Answer 18

young people
- anatomic reduction and rigid fixation to decrease risk of post traumatic OA
older patients - THR, either early (with an uncemented cup and screws) or delayed

Question 19

who gets hip fractures?

Answer 19

older people with osteoporosis
numbers of hip fractures are increasing with ageing population
majority are over 80 and 75% are female

Question 20

what co-morbidities are associated with hip fractures?

Answer 20

they tend to increase the risk of falls 
cerebrovascular insufficiency 
cardiac arrhythmias 
postural hypertension etc. 
comorbidities such as renal failure cardiopulmonary disease and chest infections can cause complications post-surgery

Question 21

how are hip fractures managed?

Answer 21

nearly all have surgery usually within 24 hours
risks of non-operative management just as high
exceptions - high risk patients expected to die very soon after injury

Question 22

what is the prognosis of hip fractures

Answer 22

20% don’t regain full independence and need long-term care, 30% fail to return to their pre-injury function
many need a stick/walking frame
some patients fail to recover and so need a wheelchair and may need assistance/ hoist to transfer from bed to chair

Question 23

risk factors for a proximal femoral fracture?

Answer 23

Risk doubles every 10 yrs after 50 yrs old
• Osteoporosis (3 times more common in females)
• Smoking
• Malnutrition
• Excess alcohol
• Impaired vision
• Neurological impairment

Question 24

how does proximal femoral fracture (hip fracture) present?

Answer 24

usually externally rotated and shortened leg
pain in groin
pain on pin roll

Question 25

what is the blood supply to the femoral head?

Answer 25

- Intramedullary artery of shaft of femur (travels up the femoral neck and into the femoral head) - Medial and lateral circumflex branches of profunda femoris - Artery of ligamentum teres

Question 26

what is an intra-capsular proximal femoral fracture?

Answer 26

``` fracture is above the trochanter lines, undisplaced, displaced (young, old and active, old), garden fractures I - valgus impacted displaced, II - undisplaced, III - displaced, VI - displaced ```

Question 27

complications of a intra-capsular proximal femoral fracture?

Answer 27

Complications: non-union, AVN (as the arterial supply of the femoral head can be disrupted)

Question 28

what is a extra-capsular proximal femoral fracture?

Answer 28

basicervical, intertrochanteric, subtrochanteric

Question 29

what are the potential complications of a proximal femoral fracture?

Answer 29

malunion | non-union (but much less than intra-capsular

Question 30

how is a proximal femoral fracture diagnosed?

Answer 30

history - fall, pain, unable to weight bear shortening external rotation - due to pull of the tendon investigations - X ray - shenton's line - MRI

Question 31

how is a proximal hip fracture treated?

Answer 31

return the patient to pre-fracture level of function | usually by operation followed by early mobilisation to avoid complications of recumbency

Question 32

management of undisplaced intra-capsular hip fracture?

Answer 32

``` Good function (young adult, high energy injury) = fixation (reduction using DHS, screws, can do multiple pinning) Risks: AVN/non-union as blood supply is probably damaged • Poor function = hemiarthroplasty (hip replacement - replacing femoral head alone ```

Question 33

management of displaced intra-capsular fracture?

Answer 33

Hemiarthroplasty or total hip replacement (THR is replacing the acetabulum as well as the femoral head) Risks: THR has higher risk of infection and displacement (esp. in the cognitively impaired) but can give better function so is given for higher functioning hip fracture patients

Question 34

how is a extra-capsular hip fracture managed?

Answer 34

Generally fixed with internal fixation, keeping the patient’s own natural hip joint blood supply in extra-capsular injuries is usually intact so tend to do fixation instead of replacement An IMN can be short or long CHS/DHS = large screw is inserted into the femoral head across the fracture line, and a plate which has a barrel attached to the lateral end of the screw and is fixed to the femoral shaft - as the patient weight bears, the screw slides into the barrel of the plate which results in compression at the fracture site promoting fracture healing

Question 35

extra-capsular Intertrochanteric fracture management

Answer 35

CHS/DHS [compression/dynamic hip screw]

Question 36

extra-capsular basicervical fracture management

Answer 36

CHS/DHS [compression/dynamic hip screw]

Question 37

extra-capsular Subtrochanteric fracture management

Answer 37

(usually in elderly patients with osteoporosis who fall onto the side, area has poor blood supply, non-union is quite common) = IMN [intramedullary nail], pre-operatively can use pain-relief and Thomas splint fracture from the greater to lesser trachanter

Question 38

summary of hip fracture management?

Answer 38

early mobility is important If both sides are vascularised = fix If one side is avascular = replace

Question 39

extra-capsular reverse oblique fracture management?

Answer 39

IMN | sort of the opposite of a subtrochanteric fracture

Question 40

how is an infection post hip fracture managed?

Answer 40

sometimes metal work is removed but not routinely if infected after fracture healing - take it out, give antibiotics etc. if infected before fracture is fully healed, might give antibiotics and then take it out but treatment is more variable

Question 41

where are the common sites of fragility fractures?

Answer 41

neck of femur (NOF) neck of humerus wrist vertebral and pelvic fractures

Question 42

what are some fraility syndromes

Answer 42

falls immobility delirium incontinence susceptibility to the side effects of medication (if patient is very frail get in a better operative state for better post-operative recovery)

Question 43

who gets femoral shaft fractures?

Answer 43

usually a result of high energy substantial risk of concomitant fracture elsewhere Can get stress fractures of the femoral shaft due to: osteoporotic bone, metastatic disease, patients with Paget’s disease, long-term bisphosphonate use (for osteoporosis - so paradoxical)

Question 44

what are the risks of a femoral shaft fracture?

Answer 44

Fat embolism, fat from medullary canal entering the damaged venous system (causes confusion, hypoxia, risk of ARDS) IF displaced, can get substantial blood loss (up to 1.5L)

Question 45

what is the management of a femoral shaft fracture?

Answer 45

Resuscitation Initial - optimise analgesia with a femoral nerve block, Thomas splint (stabilises fracture minimising further blood loss and fat embolism) Definitive - usually closed reduction and stabilisation with IMN, but can use minimally invasive plate fixation (with minimal disruption to the fracture site blood supply)

Question 46

what is the knee?

Answer 46

the articulation between the distal end of the femur and proximal tibia hinge joint mainly does flexion and extension, has small degree of rotation not as stable as the hip joint

Question 47

who gets a distal femoral fracture?

Answer 47

usually in osteoporotic bone fall on the flexed knee

Question 48

what are the types of distal femoral fracture?

Answer 48

can be extra-articular - supracondylar or intra-articular - intercondylar

Question 49

how does a distal femoral fracture present?

Answer 49

usually adopts a flexed position due to the pull of the gastrocnemii muscles

Question 50

how is a distal femoral fracture managed?

Answer 50

usually fixed with plates and screws

Question 51

who gets knee dislocation?

Answer 51

uncommon | either due to high energy injuries ow with severe hypertension and/or rotational forces with a sporting injury

Question 52

how is a knee dislocation treated?

Answer 52

``` surgical emergency - high incidence of vascular injury nerve injury and compartment syndrome should be urgently reduced need thorough neurovascular assessment knee is unstable - external fixator ```

Question 53

who gets patellar dislocation?

Answer 53

``` pretty common more common in female adolescents general ligament laxity valgus knee rotational malalignment shallow trochlear groove ```

Question 54

what is the most common patellar dislocation?

Answer 54

lateral dislocations due to either a direct blow or a contraction of the quadriceps with a rotational force with the patella not engaged in the trochlea (less than 30° flexed)

Question 55

how does a patellar dislocation present?

Answer 55

tenderness over the medial retinaculum (as medial patellofemoral ligament is torn may have haemoathrosis may get osteochondral fractures (which occasionally need retrieval fixation depending on size)

Question 56

how is a patellar dislocation managed?

Answer 56

may spontaneously reduce when knee is straightened if remains dislocated - manipulation for reduction may get subluxation sometimes needs surgical stabilisation (bony procedure for malalignment/soft tissue (MPFL) reconstruction)

Question 57

what is the prognosis of patellar dislocation?

Answer 57

10% will get another dislocation with 50% getting multiple recurrent dislocations most adolescents stabilise as they get older

Question 58

who gets a proximal tibia (plateau) fracture?

Answer 58

either high energy in young patients - might be associated with neurovascular injury to compartment syndrome or low energy in osteoporotic bone

Question 59

what is the effect of a lateral plateau fracture in the proximal tibia?

Answer 59

caused by valgus stress injury to knee, can cause failure of MCL and ACL

Question 60

what is an intra-articular fracture in the proximal tibia (plateau) fracture?

Answer 60

either split in the bone | depression of the articular surface or both

Question 61

what is the effect of a medial plateau fracture in the proximal tibia?

Answer 61

caused by varus stress, this is less common, can cause LCL | rupture

Question 62

what is the presentation of damage to the common peroneal (femoral) nerve in plateau fracture?

Answer 62

common accompanying injury | causes foot-drop due to loss of power to tibialis injury

Question 63

what is the management of a proximal tibia (plateau) fracture?

Answer 63

reduction and fixation (plates and screws, CT can help), with early motion to prevent stiffness and post-traumatic OA, may need bone graft Can use external fixator before surgery, sometimes this is used as definitive management If this all fails (which happens often) then need total knee replacement

Question 64

what causes tibial shaft fractures?

Answer 64

usually due to indirect force and either bending (transverse) fracture rotational energy (spiral fracture) or compressive force from deceleration (oblique fracture) can be a combo of these or from high energy injuries (comminuted fractures) can be open fractures - tibial shaft is subcutaneous

Question 65

what is something to be aware of with tibial shaft fractures?

Answer 65

it is the commonest cause of compartment syndrome after trauma esp in ant. compartment of leg

Question 66

what is the treatment of tibial shaft fracture?

Answer 66

up to 50% displacement and 5 degrees of angulation can be treated conservatively (cast, check X-rays) if fibula is not fractured then tibia often drifts varus if fibula is also fractured then the tibia drifts valgus Surgical stabilisation: esp. if comminuted fractures (highly unstable), open fractures or compartment syndrome - IMN is most commonly used (25% have anterior knee pain afterwards - need to discuss this with patients esp. those who have an occupation that involves kneeling) - ORIF with plates and screws (risk of affecting blood supply, non-union) Can do external fixation (can cause pin site infection/loosening) Non-union - may need bone grafting/special circular frames Compression at fracture site to promote healing Form new bone from distraction osteogenesis (making a longer bone out of a shorter one)

Question 67

healing of the tibia

Answer 67

one of the slowest healing bones in the body | union around 16 weeks and heals in 1 year