1. Reverse oblique fracture
Case for small group discussion: Fractures of the femur
Christoph Finkemeier, DE
Discussion points (overview)
Imaging
Fracture classification
Deforming forces
Treatment options
Preoperative planning
Surgical approach
Reduction
Tip Apex distance
Aftertreatment
Complications
AO Trauma Advanced Principles Course

2. Case description
85-year-old man
Fall

3. Additional imaging ?
Day 0

4. AO/OTA
31-A fractures

5. Treatment options? Day 0 Discuss treatment options:
Compression hip screw with trochanter stabilizing plate
Cephalomedullary nail (ideal)
Fixed Angle device (special circumstances)
Proximal femoral locking plate
Day 0

6. Compression hip screws alone are contraindicated for reverse oblique or AO/OTA 31-A3 fractures
Discussion points:
Deforming forces are not controlled with a compression hip screw because there is no intact lateral wall to compress the head and neck segment against. The entire proximal fragment will “slide” laterally until the barrel and lag screw abut each other. Excessive lateralization of the proximal fragment decreases the offset of the hip leading to poor hip mechanics and may lead to hardware failure or nonunion.

7. Cephalomedullary nails are load sharing and prevent lateral displacement
Discussion points:
Cephalomedullary nails are excellent choices for these fractures as they are load sharing and prevent lateral displacement.
Fixed-angle plates are indicated in some cases where a nail would potentially comminute the fracture such as in patterns where the greater trochanter or piriformis fossa are fractured.

8. Reduction techniques Positioning Supine free legged
Supine fracture table
Legs scissored
Well leg holder
Lateral free legged
Closed reduction
Open reduction with clamp
Several positioning options are available.
For low energy intertrochanteric hip fractures that will not require a lot of traction, a fracture table with the fractured extremity in traction and non-fractured extremity in a well-leg holder works well for most cases.
This set up allows for excellent imaging of the proximal femur.
The ipsilateral arm needs to be brought over the chest and out of the way of the nail entry site. The torso needs to be bent away from the operative side to open up access to the proximal femur nail entry point.
Proper positioning allows free access to the proximal femur. Excessive traction will rotate the pelvis and block access to the proximal femur.

9. Reduction by closed, indirect means alone was inadequate
A small incision was used to allow placement of a clamp to achieve reduction
Day 0

10. Nail entry point
The type of nail chosen for the procedure will determine the entry point. A piriformis cephalomedullary nail will be inserted through a piriformis entry point.
A trochanteric-entry cephalomedullary nail will be inserted through the superior portion of the greater trochanter as described in the manufacturers technique guide.
Day 0

11. Tip-apex distance A strong predictor of cut-out. TAD > 25 mm
Baumgaertner MR et al (J Bone Joint Surg Am. 1995;77:1058–1064)
Reference:
Baumgaertner MR, Curtin SL, Lindskog DM, et al. The value of the tip-apex distance in predicting failure of fixation of peritrochanteric fractures of the hip. J Bone Joint Surg Am Jul;77(7):1058–1064.
TAD > 25 mm
Risk for cut-out

12. TAD = = 8
Day 0

13. Aftercare? Day 30 Discuss aftercare:
Sutures removed when incision healed (7–14 days)
Weight bearing as tolerated
DVT prophylaxis for 21 days
Day 30

14. Summary and take-home message
31-A3.3 fractures do not have a lateral wall to compress against
Sliding hip screws (unless used with a trochanter stabilization plate) cannot resist the lateralization of the proximal fragment which is caused by the deforming forces acting on the hip.
A cephalomedullary nail inserted through the greater trochanter or the piriformis fossa provides an effective mechanical block that resists lateralization of the proximal segment.
Placing the lag screw or helical blade deep and center (TAD <25) in the head will decrease the risk of cut out.
Open reduction with a clamp or Lambotte hook are frequently necessary to achieve anatomical reduction.
Moderator should ask participants to summarize what else they have learned from this case.
References:
Haidukewych GJ, Israel TA, Berry DJ. Reverse obliquity fractures of the intertrochanteric region of the femur. J Bone Joint Surg Am May 83(5):
Baumgaertner MR, Curtin SL, Lindskog DM, et al. The value of the tip-apex distance in predicting failure of fixation of peritrochanteric fractures of the hip. J Bone Joint Surg Am Jul;77(7):1058–1064.