Neck of Femur Fractures Flashcards
List 4 factors which predispose an individual to neck of femur fractures
- Increasing age
- Osteoporosis
- Female
- Smoking
How does a NOF present?
- Shortened, abducted and externally rotated leg
- Groin or hip pain, may radiate to the knee
- Unable to weight bear
Initial investigation of choice for a suspected NOF fracture?
AP and lateral X-rays
MRI or CT scanning may be used where the x-ray is negative, but a fracture is still suspected.
What is a key sign on X-ray of a fractured NOF
Disruption of Shenton’s line
What is Shenton’s line?
Continuous curving line formed by the medial border of the femoral neck and continues to the inferior border of the superior pubic ramus.
On what x-ray view of the hip can Shentons line be seen?
AP
Give the 3 sources of blood supply to the femoral head
CHECK answer
- Retinacular vessels
- Intraosseous cervical vessels
- The artery of the ligamentum teres
Initial management of a NOF on admission
- Analgesia
- Investigations (X-rays)
- VTE risk assessment and prophylaxis (eg. LMWH)
- Pre-operative assessment (incl bloods and ECG)
- Orthogeriatrics input
How are Intra-capsular NOF fractures classified?
Garden Classification ➞ undispaced (I/II) versus displaced (III/IV)
Increasing severity with increasing grade
Which vessels are disrupted in a NOF fracture?
What is the implication of this?
CHECK
The intraosseous cervical vessels are disrupted
Femoral head nutrition is then dependent on remaining retinacular vessels and those functioning vessels in the ligamentum teres
What defines an Intertrochanteric fracture?
How is this treated?
Occur between the greater and lesser trochanter
Treated with a dynamic hip screw (AKA sliding hip screw)
What is a DHS?
Screw goes through the neck and into the head of the femur
A plate with a barrel that holds the screw is screwed to the outside of the femoral shaft
Allows compression of the fracture whilst maintaining the neck shaft angle of the femur
Give 4 complications of a DHS
- Cut out of lag screw through the femoral head
- Detachment of plate from femur
- Nonunion
- AVN of femoral head
The type of Inter-Trochanteric Fracture is based on what?
Number of parts - Increased severity with increasing grade
What is defines a sub-trochanteric fracture?
How are these treated?
Fractures within 5cm distal to the lesser trochanter
May be treated with an IM nail
What is an IM nail?
A metal pole inserted through the greater trochanter into the central cavity of the shaft of the femur
What are the the deforming forces that act on the proximal fragment of a subtrochanteric fracture
- Abduction; gluteus medius and gluteus minimus
- Flexion; iliopsoas
- External rotation; short external rotators
What are the deforming forces that act on the distil fragment of a subtrochanteric fracture
Adduction and shortening; adductors
Give 3 pros about operative-cephalomedullary nailing in the treatment of Subtrochanteric Fractures
- preserves vascularity
- load-sharing implant
- stronger construct in unstable fracture patterns
Give 4 cons about operative- cephalomedullary nailing in the treatment of Subtrochanteric Fractures
- reduction technically difficult
- nail can not be used to aid reduction
- fracture must be reduced prior to and during passage of nail
- may require percutaneous reduction aids or open clamp placement to achieve and maintain reduction
What is an intra-capsular fracture?
A break in the femoral neck, within the capsule of the hip joint. Affects the area proximal to the intertrochanteric line
What is the biggest danger with Intra-capsular fractures?
Blood supply to femoral head disrupted ➞ risk of avascular necrosis (AVN)
Compare a displaced vs non-displaced intracapsular fracture
Displaced disrupts supply to the femoral head
Non-displaced may have an intact blood supply to femoral head
List 3 Surgical managements for an Intra-capsular fractures
- Internal Fixation
- Hemiarthroplasty
- THR
When is Internal fixation used for Intra-capsular fractures?
Non-displaced or minimally displaced IC fractures
Also Displaced IC fractures in the young (but may require open reduction -orthopaedic emergency) or in the elderly (controversial)
When is arthroplasty (hemi, THR) used for Intra-capsular fractures?
Displaced ICF
Compare a Hemiarthroplasty vs THR?
When does one tend to be offered over another?
Hemiarthroplasty:
- Only head of the femur is replaced, the acetabulum is left in place.
- Generally offered to patients with limited mobility or significant co-morbidities
THR:
- Both the head of the femur and the socket are replaced.
- Generally offered to patients who can walk independently and are fit for surgery
What is the most common approach for a hemiarthroplasty + explain?
List 2 risks of this
Lateral (Hardinge) Approach
- Fascia Lata split to expose Vastus Lateralis
- Splits both Gluteus Medius and Vastus Lateralis
Risks:
- Femoral nerve damage
- Denervation Gluteus Medius
According to NICE guidelines, within what timeframe must a NOF fracture be surgically treated?
Either the same day or the day after the patient is admitted (within 48 hours).
