Common fractures and dislocations of the lower limb Flashcards
Classify the types of hip fracture
Intracapsular/subcapital: NOF
- Subcapital: below the femoral head
- Transcervical: across the mid-femoral neck
- Basicervical: across the base of the femoral neck
Extracapsular
- Intertrochanteric
- Subtrochanteric
What are the common clinical signs of a hip fracture?
When may these be absent?
Shortened and externally rotated leg
May be absent if fracture is not displaced
Describe three X-ray features of a hip fracture
Obtain AP pelvis and lateral hip radiographs
- Shenton’s line disruption
- Lesser trochanter more prominent: external rotation
- Femur flexion and external rotation: unopposed iliopsoas
- Asymmetry of lateral femoral neck/head
- Sclerosis in fracture plane; smudge sclerosis from impaction
- Bone trabecular angulation
Which artery supplies most of the blood to the femoral head?
Medial femoral circumflex artery
What imaging should be offered in suspected occult hip fracture?
MRI within 24hr
Otherwise, consider CT
Describe the preoperative pain management for hip fractures
Assess pain:
- Immediately upon presentation at hospital
- Within 30 minutes of administering initial analgesia
- Hourly until settled on the ward
- Regularly as part of routine nursing observations
Analgesia should allow passive external rotation of leg, nursing care and rehabilitation
Paracetamol every 6 hours preoperatively; consider opioids and nerve blocks
NSAIDs not recommended
Describe the postoperative pain management for hip fractures
- Paracetamol every 6 hours postoperatively
- Additional opioids if insufficient postoperative pain relief
NSAIDs not recommended
What is the aim behind operating on hip fractures?
Operate with the aim to enable full weight bearing (without restriction) in the immediate postoperative period
When is a total hip replacement, rather than hemiarthroplasty, offered to patients with a displaced intracapsular hip fracture?
Total hip replacement if all of the following:
- Prior, walked independently outdoors using a stick at most
- Not cognitively impaired
- Medically fit for anaesthesia and the procedure
What surgical procedures are offered for the different types of hip fracture?
- Screw fixation or conservative: undisplaced intracapsular
-
Replacement arthroplasty: displaced intracapsular
- Total or hemiarthroplasty depending on patient
- Extramedullary implants (DHS): trochanteric fractures
- Intramedullary nail: subtrochanteric fracture.
Describe the clinical features of hip dislocation
Hip dislocation usually occurs posteriorly, with:
- Leg shortening
- Flexion
- Internal rotation
May also have fracture of acetabulum or soft tissue injury
Which nerve may be damaged with hip dislocation?
State an associated complication of this
Sciatic nerve
Equinus foot deformity
Which patients are more likely to suffer an hip dislocation?
Patients with total hip replacement (THR)
How is hip dislocation treated?
- Reduction under GA
- Traction for 3 weeks: promotes joint capsule healing
Describe the typical cause of a femoral shaft fracture
High force trauma eg. RTA
Otherwise, pathological fractures should be considered
Describe the common radiographic findings of a femoral shaft fracture
- Proximal bone fragment:
- Flexed (iliopsoas)
- Abducted (gluteus medius)
- Externally rotated (gluteus maximus)
- Distal fragment
- Shortened (hamstrings)
- Adducted
- Externally rotated (adductors)
What is the treatment of a femoral shaft fracture?
- Stabilise with resuscitation and traction
- Locked intramedullary nail
What is the typical cause of a tibial fracture?
High force trauma Stress injury may occur with chronic low force trauma
Define a toddler’s fracture
Spiral distal tibial fracture seen in young children. Associated with a twisting injury, may present with refusal to weight-bear. Should never occur in children not yet walking ➔ consider non-accidental injury and alert paediatric team
Name 3 reasons to revise a total hip replacement
Aseptic loosening (most common reason)
Pain
Dislocation Infection
Describe the 3 types of patella fractures
- Undisplaced fracture across the patella
- Comminuted fracture: fall or direct blow
- Transverse fracture with a gap: forced passive flexion whilst quadriceps contracted
Describe the clinical features of a patella fracture
- Painful swollen knee
- If separated, gap may be palpable
- Usually blood in joint
Helpful to establish if patient can extend knee, as this will influence treatment
Outline the treatment of a undisplaced patellar fracture
As extensors are intact, treatment is protective
- Aspirate if haemarthrosis threatens skin
- Plaster cast for 4-6 weeks
- Daily quadricep exercises
Outline the treatment of a comminuted patellar fracture
Extensors are intact, but patella is irregular
Attempts should be made to preserve the patella
- Partial patellectomy + circlage wire
- Hinge brace to mould fragments
- Resurfacing if still symptomatic
Outline the treatment of a displaced transverse patella fracture
Disrupted extensor mechanism
- Internal fixation of fragments: tension band
- Brace worn until active extension regained
- Daily flexion and extension exercises
What is the commonest cause of patella dislocation?
Traumatic disloaction due to sudden contraction of quadriceps muscles while the knee is stretched in valgus and external rotation
Describe the clinical features of dislocation of the patella
- Displaced patella sits laterally
- Uncovered prominent medial femoral condyle
- Loss of active and passive knee movement
What x-ray changes are seen with dislocation of the patella?
- Patella displaced laterally
- Tilted or rotated
- 5%: associated osteochondral fracture
How is discloation of the patella treated?
- Closed reduction
- Plaster back-slab for 2 weeks
- Physiotherapy to regain flexion
- Patella holding brace may be used for 4 weeks
