Lower limb fractures Flashcards
What are the Ottawa Rules for ankle x-rays?
The Ottawa Rules for ankle x-rays have a sensitivity approaching 100%.
When is an ankle x-ray required?
An ankle x-ray is required if there is pain in the malleolar zone and any one of the following findings:
- Bony tenderness at the lateral malleolar zone (from the tip of the lateral malleolus to the lower 6 cm of the posterior border of the fibula).
- Bony tenderness at the medial malleolar zone (from the tip of the medial malleolus to the lower 6 cm of the posterior border of the tibia).
- Inability to walk four weight-bearing steps immediately after the injury and in the emergency department.
Are there Ottawa rules for other injuries?
Yes, there are Ottawa rules available for both foot and knee injuries.
What is a common site of fracture in elderly females?
The hip is a common site of fracture, especially in osteoporotic, elderly females.
What is a risk associated with displaced hip fractures?
Avascular necrosis is a risk in displaced fractures due to the blood supply to the femoral head.
What are the classic signs of a hip fracture?
Pain, a shortened leg, and an externally rotated leg.
Can patients with non-displaced neck of femur fractures weight bear?
Yes, patients with non-displaced or incomplete neck of femur fractures may be able to weight bear.
What are the two classifications of hip fractures based on location?
Intracapsular (subcapital) and extracapsular.
What defines an intracapsular hip fracture?
From the edge of the femoral head to the insertion of the capsule of the hip joint.
What are the types in the Garden classification system?
Type I: Stable fracture with impaction in valgus.
Type II: Complete fracture but undisplaced.
Type III: Displaced fracture, usually rotated and angulated, but still has boney contact.
Type IV: Complete boney disruption.
Which types of fractures most commonly disrupt blood supply?
Types III and IV.
What is the management for an undisplaced intracapsular hip fracture?
Internal fixation, or hemiarthroplasty if unfit.
What does NICE recommend for displaced intracapsular hip fractures?
Replacement arthroplasty (total hip replacement or hemiarthroplasty) for all patients.
When is total hip replacement favored over hemiarthroplasty?
If patients can walk independently outdoors with a stick, are not cognitively impaired, and are medically fit for anaesthesia and the procedure.
What is the management for stable intertrochanteric fractures?
Dynamic hip screw.
What is the management for reverse oblique, transverse, or subtrochanteric fractures?
Intramedullary device.
What are metatarsal fractures?
Metatarsal fractures are relatively common and can affect one or multiple metatarsals due to direct trauma or crush injuries.
When a fracture occurs due to repeated mechanical stress, it is termed a stress fracture. The metatarsals are the most common site of stress fractures.
Which metatarsal is the most commonly fractured?
The proximal 5th metatarsal is the most commonly fractured metatarsal and the most common site of midfoot fractures.
Which metatarsal is the least commonly fractured?
The 1st metatarsal is the least commonly fractured metatarsal.
What are proximal avulsion fractures?
Proximal avulsion fractures (pseudo-Jones fractures) are the most common type of 5th metatarsal fractures, occurring at the proximal tuberosity and usually associated with a lateral ankle sprain.
What are Jones fractures?
Jones fractures are much less common and are transverse fractures at the metaphyseal-diaphyseal junction.
Who is most likely to experience metatarsal stress fractures?
Metatarsal stress fractures occur in otherwise healthy athletes, such as runners.
Where is the most common site of metatarsal stress fractures?
The most common site of metatarsal stress fractures is the 2nd metatarsal shaft.
What are the features of metatarsal fractures?
Features include pain and bony tenderness, swelling, and an antalgic gait.
What investigations are used for metatarsal fractures?
X-rays distinguish between displaced and non-displaced fractures, guiding management options. Stress fractures may appear normal on X-ray, but a periosteal reaction may be seen after 2-3 weeks.
An isotope scan or MRI may help establish the presence of a stress fracture, as X-rays are often normal in up to half of all cases.
What is the patella?
The patella is a sesamoid bone that develops within the quadriceps tendon, dividing it into the quadriceps tendon superiorly and the patella ligament inferiorly.
What role does the patella play in the knee?
The patella protects the knee from physical trauma and plays an important role in the extensor mechanism of the knee.
How does the patella increase the efficiency of the quadriceps?
The patella increases the distance of the quadriceps tendon from the centre of rotation (the knee joint), making it easier to apply force.
What is the shape of the patella?
The patella is roughly triangular in coronal and axial planes.
What are the surfaces of the patella?
The anterior surface is flat, while the posterior surface has a medial and lateral facet that articulates with the femur at the patellofemoral joint.
What types of injuries can occur to the patella?
The patella can be injured by direct or indirect means.
What is a direct injury to the patella?
A direct injury usually follows a blow or trauma to the front of the knee, resulting in an undisplaced crack or comminuted fracture.
What is an indirect injury to the patella?
An indirect injury occurs when the quadriceps forcefully contracts against a block to knee extension, often resulting in a transverse patella fracture.
What are the clinical features of a patella fracture?
Clinical features include considerable swelling, bruising, pain and tenderness localized to the patella, and a palpable gap.
How can the extensor mechanism be assessed?
If the patient is able to straight leg raise, the extensor mechanism is grossly intact.
What investigations are used to diagnose patella fractures?
Plain films are usually sufficient, requiring a minimum of two views, often an AP and lateral.
How are undisplaced patella fractures managed?
Undisplaced fractures can be managed non-operatively in a hinged knee brace for 6 weeks, allowing full weight bearing.
How are displaced patella fractures managed?
Displaced fractures should be considered for operative management with tension band wire, inter-fragmentary screws, or cerclage wires, followed by a hinged knee brace for 4 to 6 weeks.
