Neck of Femur Fractures Flashcards
What are the two types of NoF fractures?
Intracapsular and extracapsular
What is the standard patient for NoF fracture?
Caucasian woman in her 7th/8th decade
What is the usual underlying pathophysiology in low trauma NoF fracture
Osteoporosis
Give three types of intracapsular fracture
Subcapital
Transcervical
Basiccervical
Give two types of extracapsular fracture
Intertrochanteric
Subtrochanteric
Give four clinical features of NoF fracture
Shortened limb
Externally rotated
Painful, tender hip
Failed leg raise
What are the two main questions to ask when looking at a NoF radiograph?
Is there a fracture?
Is it displaced?
What are you looking for in fracture?
Breaks in cortices
Length of spread
What are two clues that a fracture is displaced?
Disruption of shentons line
Mismatch between trabecular lines of femoral head and the supra-acetabilar part of the pelvis
Why is displacement an importnat thing to diagnose?
Undisplaced or impacted fracture do better, displaced do worse
What is Shenton’s line?
Line along lesser trochanter, femoral neck and inferior superior pubic ramus
What is Gardners classification used for?
Classifying intracapsular fractures of the hip
Give the four stages of GArdner classifcation
Stage I – Incomplete impacted fracture with femoral head tilted into slight valgus
Stage II – Complete but undisplaced fracture
Stage III – Complete fracture with moderate displacement
Stage IV – Severely displaced fracture
Which gardners have the best prognosis?
I and II as less displaced
What is the difference between III and IV
III usually does not have alignment of trabecular lines of the femoral head with the supra-acetabular trabecula. IV usually does, as proximal fragment completely displaced from neck of femur and rests in neutral position.
Give four NoF fractures not to miss
1) Stress fractures – High index of suspicion of NoF for elderly patients with hip pain and young patients with pain who do regular impact loading sports
2) Undisplaced fractures – Very subtle fracture line can lead to it being missed
3) Painless fractures – bed ridden patients may fracture their hip and lead to impaction
4) Multiple fractures – Patient with a femoral shaft facture may also have a NoF fracture
Give some investigations for NoF fracture
- AP and lateral radiograph
- FBC and cross-match
- Renal function, glucose, ECG, CXR
What is the initial management for NoFF?
Initial management is splinting and pain relief, with compartment block (femoral, obturator and lateral cutaneous nerve) if surgery is going to be delayed.
How do you treat a displaced intracapsular NOFF?
- Hemiarthroplasty in unfit patients, THR in fit patients
When would you use THR for dis intra NOFF
THR sometimes used in younger patients, delayed treatment with acetabular damage or patients with metastatic or pagets disease.
How would you treat undisplaced intracapsular fracture?
o Fracture is reduced internally to start
Patient under anaesthesia the fracture is disimpacted by applying traction with the hip held in 45* of flexion and slight abduction, the limb is then slowly brought into extension and finally internally rotated. As traction is released the fracture reimpacts in the reduced position.
Open reduction can also be tried in stage III and IV fractures in patients
What is important to do post-op?
- Breathing exercises
- Early mobilization
What is the prognosis for NoFF?
One in ten patients die within thirty days, one in five within one year. High risk of post-operative complications.
What are the three sources of blood of the femoral head?
1) Ascending cervical branches of the medical circumflex and lateral cicumflex arteries which arise from femoris profundus and run within the capsular retinaculum before entering bone at the articular margin of the femoral head
2) The intramedullary vessels of the femoral neck
3) The vessels of ligamentum teres
What happens to blood supply in an intracapsular NOFF?
In an intracapsular fracture the intramedullary supply is always disrupted and the medial and lateral circumflex may be torn if the fracture is displaced. Risk of avascular necrosis.
What is the rate of avascular necrosis in NoF patients?
This complication occurs in 30% patients with displaced fractures and 10% of those without.
Give two complications of NoF repair?
Avascular necrosis
Non-union
Give four types of extracapsular fracture?
Type 1 – Undisplaced, uncomminiuted
Type 2 – Displaced, minimal comminution, lesser trochanter fracture, varus
Type 3 – Displaced, greater trochanter fracture, comminuted, varus
Type 4 - Severely comminuted, Subtrochanteric extensiom
What is the mechanism of injury of extracapsular fracture?
The fracture is caused either by a fall directly onto the greater trochanter or by an indirect twisting injury.
What is the treatment for intertrochanteric fracture?
Intertrochanteric fractures are treated by early internal fixation. Fracture reduction is performed on fracture table that provides slight traction and internal rotation. The fracture is often fixed with a sliding screw in conjunction with a plate or intramedullary nail. Alternatively a dynamic hip screw can be used.
How do kids break their hips?
Jumping out of trees
Why are large forces required to break sub-trochanteric neck of femur?
Due to the calcar femorale, a stout pillar of bone located posteromedially
Why is blood loss often large in subtrochanteric fractures?
Intertrochanteric fractures are treated by early internal fixation. Fracture reduction is performed on fracture table that provides slight traction and internal rotation. The fracture is often fixed with a sliding screw in conjunction with a plate or intramedullary nail. Alternatively a dynamic hip screw can be used.
What is the Nottingham Hip Fracture score?
30-day mortality risk of fractures
Why is leg shortened and externally rotated?
Iliopsoas and Gluteus Medius
Outline the blood supply to the neck of femur
1) Ascending cervical branches of the medical circumflex and lateral cicumflex arteries which arise from femoris profundus and run within the capsular retinaculum before entering bone at the articular margin of the femoral head
2) The intramedullary vessels of the femoral neck
3) The vessels of ligamentum teres
How do you fix a displaced intracapsular facture?
Hemiarthroplasty in unfit patients, THR in fit patients
How do you fix an undisplaced intracapsular fracture?
Once fracture is reduced it is held with cannulated or dynamic hip screws. Three screws in parallel are usually used. The inferior screw extends from level of lesser trochanter on lateral side and in parallel with inferior cortex of the neck. Two other screws are inserted more proximally, straddling anterior and posterior margins of the femoral neck of the lateral x-ray.
