Subtrochanteric Fractures

Question 1

What are the deforming forces in a subtrochanteric fracture?

Answer 1

Proximal:

1) abduction- gluteus medius/minimus
2) flexion- iliopsoas
3) external rotation- short external rotators

Distal:
1) adduction/shortening- adductors

Question 2

What are radiographic clues of a bisphosphonate related fracture?

Answer 2

1) lateral cortical thickening
2) medial spike
3) lack of comminution
4) transverse fracture

Question 3

What are indications to use a fixed angle blade plate in subtrochanteric fractures?

Answer 3

1) surgeon preference
2) associated femoral neck fracture
3) narrow medullary canal
4) pre-existing femoral shaft deformity

Question 4

What are the advantages of lateral positioning for placement of a CM nail for intertrochanteric fractures?

Answer 4

1) allows for easier reduction of the distal fragment to the flexed proximal fragment
2) allows for easier access to entry portal, especially for piriformis nail

Question 5

What is the most frequent intraoperative complication with antegrade nailing of a subtrochanteric femur fracture?

Answer 5

varus and procurvatum (or flexion) malreduction

Question 6

What are additional risks to consider with plate or nail fixation of bisphosphonate fractures?

Answer 6

nail fixation:
increased risk of iatrogenic fracture
because of brittle bone and cortical thickening
increased risk of nonunion with nail fixation resulting in increased need for revision surgery

plate fixation:
increased risk of plate hardware failure
because of varus collapse and dependence on intramembranous healing inhibited by bisphosphonates

Question 7

What is associated with low energy subtrochanteric fractures?

Answer 7

Pathological fractures

Also bisphosphonate use, esp alendronate