Neck of Femur Fractures

Question 1

What are the two types of NoF fractures?

Answer 1

Intracapsular and extracapsular

Question 2

What is the standard patient for NoF fracture?

Answer 2

Caucasian woman in her 7th/8th decade

Question 3

What is the usual underlying pathophysiology in low trauma NoF fracture

Answer 3

Osteoporosis

Question 4

Give three types of intracapsular fracture

Answer 4

Subcapital
Transcervical
Basiccervical

Question 5

Give two types of extracapsular fracture

Answer 5

Intertrochanteric

Subtrochanteric

Question 6

Give four clinical features of NoF fracture

Answer 6

Shortened limb
Externally rotated
Painful, tender hip
Failed leg raise

Question 7

What are the two main questions to ask when looking at a NoF radiograph?

Answer 7

Is there a fracture?

Is it displaced?

Question 8

What are you looking for in fracture?

Answer 8

Breaks in cortices

Length of spread

Question 9

What are two clues that a fracture is displaced?

Answer 9

Disruption of shentons line

Mismatch between trabecular lines of femoral head and the supra-acetabilar part of the pelvis

Question 10

Why is displacement an importnat thing to diagnose?

Answer 10

Undisplaced or impacted fracture do better, displaced do worse

Question 11

What is Shenton’s line?

Answer 11

Line along lesser trochanter, femoral neck and inferior superior pubic ramus

Question 12

What is Gardners classification used for?

Answer 12

Classifying intracapsular fractures of the hip

Question 13

Give the four stages of GArdner classifcation

Answer 13

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

Question 14

Which gardners have the best prognosis?

Answer 14

I and II as less displaced

Question 15

What is the difference between III and IV

Answer 15

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.

Question 16

Give four NoF fractures not to miss

Answer 16

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

Question 17

Give some investigations for NoF fracture

Answer 17

• AP and lateral radiograph
• FBC and cross-match
• Renal function, glucose, ECG, CXR

Question 18

What is the initial management for NoFF?

Answer 18

Initial management is splinting and pain relief, with compartment block (femoral, obturator and lateral cutaneous nerve) if surgery is going to be delayed.

Question 19

How do you treat a displaced intracapsular NOFF?

Answer 19

• Hemiarthroplasty in unfit patients, THR in fit patients

Question 20

When would you use THR for dis intra NOFF

Answer 20

THR sometimes used in younger patients, delayed treatment with acetabular damage or patients with metastatic or pagets disease.

Question 21

How would you treat undisplaced intracapsular fracture?

Answer 21

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

Question 22

What is important to do post-op?

Answer 22

• Breathing exercises

- Early mobilization

Question 23

What is the prognosis for NoFF?

Answer 23

One in ten patients die within thirty days, one in five within one year. High risk of post-operative complications.

Question 24

What are the three sources of blood of the femoral head?

Answer 24

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

Question 25

What happens to blood supply in an intracapsular NOFF?

Answer 25

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.

Question 26

What is the rate of avascular necrosis in NoF patients?

Answer 26

This complication occurs in 30% patients with displaced fractures and 10% of those without.

Question 27

Give two complications of NoF repair?

Answer 27

Avascular necrosis

Non-union

Question 28

Give four types of extracapsular fracture?

Answer 28

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

Question 29

What is the mechanism of injury of extracapsular fracture?

Answer 29

The fracture is caused either by a fall directly onto the greater trochanter or by an indirect twisting injury.

Question 30

What is the treatment for intertrochanteric fracture?

Answer 30

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.

Question 31

How do kids break their hips?

Answer 31

Jumping out of trees

Question 32

Why are large forces required to break sub-trochanteric neck of femur?

Answer 32

Due to the calcar femorale, a stout pillar of bone located posteromedially

Question 33

Why is blood loss often large in subtrochanteric fractures?

Answer 33

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.

Question 34

What is the Nottingham Hip Fracture score?

Answer 34

30-day mortality risk of fractures

Question 35

Why is leg shortened and externally rotated?

Answer 35

Iliopsoas and Gluteus Medius

Question 36

Outline the blood supply to the neck of femur

Answer 36

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

Question 37

How do you fix a displaced intracapsular facture?

Answer 37

Hemiarthroplasty in unfit patients, THR in fit patients

Question 38

How do you fix an undisplaced intracapsular fracture?

Answer 38

 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.