DHS (dynamic hip screw) vs PFNA (proximal femoral nail antirotation) for Intertrochanteric fractures comparision - Dr Chintan N Patel

1. Antirotation Proximal Femoral Nail
Versus Dynamic Hip Screw
For Intertrochanteric Fractures:
A meta-analysis of randomized controlled studies
Orthopaedics & Traumatology: Surgery & Research
(2013) 99, 377—383
Dept of Orthopaedics , J.N. Medical College
and
Dr. Prabhakar Kore Hospital and MRC,
Belgaum

2. INTRODUCTION
• Inter-trochanteric fractures are becoming common as our
population ages. Treatment of peritrochanteric fracture is based on
patient’s medical condition, bone quality and fracture
configuration.
• Established surgical options for peritrochanteric fractures mainly
include DHS, Gamma nail, and proximal femoral nail, but the
optimal treatment choice continues to be highly debated.
• Generally, Dynamic Hip Screw (DHS) internal fixation is one of
the most primary options. For stable or minimally displaced
pertrochanteric fractures (AO 31-A1 fractures, i.e., basicervical
fractures and simple pertrochanteric fractures), the DHS fixation
produces reliable results. However, in unstable fractures, the DHS
device performs less well with a relatively higher incidence of
internal fixation failure.

3. INTRODUCTION
• The Proximal Femoral Nail Antirotation (PFNA) is an
intramedullary device with a helical blade rather than a
screw, for better purchase in the femoral head and has been
adopted for patients with unstable peritrochanteric
fractures. (AO 31-A2 and 31-A3)
• Thus, to provide the most comprehensive assessment of
the PFNA and DHS for peritrochanteric fractures, we
performed this meta-analysis based on all relevant
randomized controlled trials comparing PFNA with DHS
for peritrochanteric fractures.
• The hypothesis of present study was that
“PFNA achieved better efficacy for peritrochanteric
fractures compared with DHS.”

4. • Proximal femoral fractures (PFFs) carry high mortality
rates of 5% after 1 month and 15% after 6 months.
• Among PFFs, 65% are extra-capsular. The main
challenge with extra-capsular PFFs is instability in the
event of comminution and rupture of the posteromedial
cortex, as seen in complex pertrochanteric fractures,
intertrochanteric fractures extending into the diaphysis,
and subtrochanteric fractures.

5. • The rate of reoperation for mechanical
complications of any type remains as high
as 8%.
• Mechanical complications include
hardware-related fractures and blade cut-out
with a risk of acetabular penetration.
• Greater fracture instability and osteoporosis
severity are associated with a higher risk of
mechanical complications

6. Materials and methods:
• Relevant randomized controlled trials comparing PFNA
with DHS for pertrochanteric fractures were assessed for
eligibility and included into this meta-analysis.
• The inclusion criteria of this meta-analysis were:
randomized controlled trials comparing PFNA with DHS
for pertrochanteric fractures and reporting at least one of
these main outcomes, including operating time, blood loss,
all causes for mortality, and complications.

8.  Five randomized controlled trials were finally included into this meta-
analysis. Pooled results showed there were less blood loss (weighted
mean difference Blood loss = −249.75 ml, 95%CI −303.83 to −195.67,
P < 0.0001) and fewer complications (Odds ratio = 0.40, 95%CI 0.23
to 0.70, P = 0.001) in the PFNA group compared with the DHS group.
However, there was no difference in term of mortality between those
two groups (Odds ratio mortality = 1.13, 95%CI 0.47 to 2.69, P =
0.79).

9. Intertrochanteric fractures
 Extracapsular fractures of the proximal
femur involving the area between the
greater and lesser trochanter
 50% of all fractures of the proximal
femur
Risk factors in the elderly:
• Less soft-tissue cover
• Muscle weakness
• Secondary osteoporotic fractures
• Poor protective response
• Impaired cognition/vision
• Comorbidity/drugs

11. AO Classification

13. Treatment Goals
• Stable internal fixation, early mobilization and
full weight bearing ambulation.
• Good quality of fixation depends upon
– Bone quality
– Fracture pattern
– Fracture reduction
– Implant choice
– Implant placement

14. Treatment options
• Nonoperative:
– 12-14 weeks bed rest
– Buck‘s traction / Russel’s skeletal traction
– Plaster spica
– Derotation boot
– Thomas splint immobilization
• Operative
• Extra Medullary
- Dynamic hip screw
- Trochanteric stabilizing plate
- 95 degree Angle blade plate
• Intramedullary Nail
– Gamma Nail
– Intramedullary hip screw
– Condylar blade plate
• External fixator
• Replacement arthroplasty

15. Implant
Extramedullary Intramedullary
Gamma-nailPFN
Blade plate DHS

16. Stable
Easy to treat by any method
Un Stable
DIffficult to treat
If lateral wall is intact and lesser trochanter is intact it is stable,
if any one of them is broken it is unstable
How to identify an unstable fracture?

17. Pre Operative Day 1
31. A2.1 31. A3. 3
31% of A2 Type Fractures

18. Choice of implant
• There is evidence that a
rigid extramedullary
fixation bears too high a
risk for:
– early failure (cut out)
– more postoperative hip pain
– reduced postoperative
mobility

19. • The IM component helps to buttress against
fracture collapse and medialization of the distal
fracture fragment, particularly in unstable (ie,
reverse obliquity) intertrochanteric fractures.
• The percutaneous insertion of the IM device may
reduce the amount of surgical trauma.

20. • Few studies have assessed method of cephalic fixation with
proximal reconstruction nail , which theoretically ensures
rotational and angular stability with a single component, as well
as cancellous bone compaction around the blade inserted by
impaction. Cancellous bone compaction improves anchoring in
osteoporotic bone, thereby decreasing the risk of cut-out.
• A multicentre study by Simmermacher et al. suggests that, by
controlling the metaphyseal impaction, the helical blade may
prevent penetration through the femoral head and allow full
weight-bearing in over three-quarters of patients with unstable
fractures.

21. Reduced lever arm
Extramedullary Plate =< Intramedullary
Plate (Nail)

22. Less telescoping

23. Prevents medialisation-Shaft

24. Outcome of Sliding Hip Screw in Un Stable Fractures
Is DHS still the Gold Standard?

25. Changes in the Nailing systems
1. Change of entry point
– Piriformis entry/ modified medial trochanteric
portal

26. 2. more proximal location of distal
interlocking bolt

27. 3. option for oblique static distal locking bolt

28. 4. The main change is in the proximal locking
mechanism

29. “ Z effect ”

30. “Reverse Z effect”

31. 5 degree medio-lateral angle makes it easier to insert
Difference between PFNA and A2

32. Difference between PFNA and A2

33. DHS PFNA PFNA2
1. Open procedure so,
Significantly higher need for
transfusion
2. Increased surgical time
3. Longer time to mobilization
4. Longer hospital stay
5. Higher postoperative
complication rate
6. Lower rates of union 91.6%
1. Semi close procedure so, Lesser or no need for blood
transfusions
2. Shorter surgical time & Lesser fluoroscopy exposure
3. Direct full weight bearing
4. Shorter length of hospital stay
5. Higher Harris Hip scores at short term evaluation
1. Minimizes the risk of
lateral impingement to
the lateral cortex
2. Shortest surgical time
3. Easier nail insertion
4. Highest union rates
97.15%

34. AAOS – Ten tips to better outcome
1. Use the tip to apex distance
2. No lateral wall, no hip screw
3. Know the unstable intertrochanteric fracture patterns and Nail them
4. Beware of the anterior bow of the femoral shaft
5. When using a trochanteric entry nail, start slightly medial to the exact
tip of the greater trochanter
6. Donot ream an unreduced fracture
7. Be cautious about the nail insertion trajectory and do not use a
hammer to seat the nail
8. Avoid varus angulation of the proximal fragment – use the
relationship between the tip of the trochanter and the center of the
femoral head
9. When nailing, lock the nail distally if the fracture is axially or
rotationally unstable
10. Avoid fracture distraction when nailing

35. Summary
• 31-A1 (“stable”) fractures
might be treated with any
sliding device
• 31-A2 (“unstable“) fractures
can be treated either with an
intramedullary device which
permits immediate full
weight bearing or a sliding
hip screw

36. ConclusionConclusion
• In conclusion, PFNA can benefit
peritrochanteric fractures patients with less
blood loss and fewer complications compared
with DHS.