1. Midshaft Femur Shaft Fracture: Always Antegrade Nailing
Brent L. Norris
Clinical Associate Professor
Chairman, OSU Orthopaedic Surgery Training Program
Oklahoma State University
Co-Director, Orthopaedic Trauma Fellowship
University of Oklahoma
Tulsa, OK

2. Disclosures AAOS Program Committee Member
AONA: Fellowship grant support
Depuy/Synthes Consultant
Acumed Consultant
Wishbone Medical Consultant
Endeavor Ortho Principle
ORI Principle

3. What’s the Big Deal?

4. Thank You!

5. “It’s just a femur fracture, lets nail it!”
History:
48 yo male
Ped struck
Pneumothorax
Subarachnoid hemorrhage
Liver laceration
Femur and forearm fx
CNS 52=25 Abdo 42=16 ISS=50 Ortho 32=9

6. USUALLY IM NAILS BUT SOMETIMES ALL THE ABOVE
Types of Fixation
IM Nails
Plates and Screws
External Fixation
USUALLY IM NAILS BUT SOMETIMES ALL THE ABOVE

7. Concerns associated with IM Femoral Nailing Late 1990’s
Antegrade vs retrograde
Trochanteric vs piriformis
Reamed vs unreamed
Timing of fixation
Early verses delayed
Extending the indications of IM femoral nailing

8. Antegrade Femoral Nailing
Piriformis fossa starting point
Trochanteric starting point

9. Antegrade Femoral Nail-Piriformis Start
Advantages
Aligned with medullary canal
Less hoop stresses
No violation of G. Medius Tendon
Proven track record
Disadvantages
May damage short external rotators
Injury to blood supply femoral head
Hard to find in obese patients

10. Antegrade Femoral Nailing Trochanteric Start
Advantages
Easy to find
Supine nailing easier
Less injury to blood supply femoral head?
Less OR time and blood loss
Disadvantages
Not in line with medullary canal
Potential for proximal fragment malalignment
Femoral bursting (ANTERIOR)
Damage to G. Medius tendon/muscle

11. Antegrade Femoral Nail
Insertion Forces Depend Upon
Nail Geometry/Characteristics
Curvature of femur
Entry portal
Piriformis/Trochanteric
Size of the canal
Size of the proximal fragment

12. Antegrade Femoral Nail
Nail Insertion with Improper Technique
Increased comminution
Malalignment of the fracture

13. Advances in IM Nailing IM Reaming Nail GeometryMetallurgy
Flexible reamers
Nail GeometryMetallurgy
Cannulatioin, radius of curvature, interlocking options
SS, Ti, C
Extending Nailing Indications
Nailing metaphyseal, articular injuries

14. Intramedullary Reaming
Technique used to enlarge an already existing hole
Technique
Cannulated system
Front cutting (initial reaming)
Side cutting
Over ream by 1mm to 1.5mm
Prevents “longitudinal jamming”

15. Intramedullary Reaming
Ideal Design to Decrease IM Pressure
Deep flutes
Narrow shaft
Small diameter bulb
Slow advancement
Frequent pullback

16. IM Reaming Advantages Biomechanical Stimulus
Allows  diameter, stronger nail
Creates more contact between the nail/bone
Improves fracture stability
Stronger nail
Increased frictional forces
Increases rate of fracture union
Increased blood flow/bone graft

17. IM Reaming Disadvantages
Risks to blood supply
Intramedullary blood supply is injured
Possible necrosis of diaphyseal bone
Reaming plus insertion of tight fitting nail can injure  70% of cortical bone vascularity
Vascularity begins reconstitution at 2-3 wks
Nearly complete restoration at 8 weeks
May increase risk for infection (early on)
Causes long term cortical remodeling*
Increased cortical thinning
Increased cortical porosity

18. Intramedullary Reaming
Increases medullary pressure
Embolization of marrow contents
Increases cortical temperature
Upwards of 50 degrees C
Thermal necrosis of cortical bone

19. Reamed vs Unreamed Reamed Nailing Unreamed Nailing
Longer operating time
Increased blood loss
Fewer complications
Increased pulmonary dysfunction in lung injured patients*
Unreamed Nailing
Smaller nails leading to increased nail/screw failures ??
Increased nonunions ??
Indicated in some polytrauma

20. Reamed vs ‘Some reaming’ vs Unreamed
Higher Union Rate: 98.3% vs 92.5
RR of nonunion is 4.5x greater without reaming
Canadian Orthopaedic Trauma society, JBJS, 2003
SPRINT Trial (TIBIA)(J Bone Joint Surg Am Dec 1; 90(12): 2567–2578)
Slightly increased union in closed fx with reaming
NO difference with open fxs
Fewer intraoperative complications
Tornetta et al., J Orthop Trauma, 1997
Shepard et al., Orthop Trans, 1997

21. Clinical Results
Regardless of the current controversy reamed antegrade femoral nailing has a proven track record
High union rates
Low complications rates
Excellent return of function
Clinical concerns:
pulmonary dysfunction
postoperative hip pain
difficult starting point

22. Clinical Results Retrograde Nailing Antegrade Nailing
61 cases (reamed)
1 union: 85%
2 union: 95%
One septic knee
Normal knee function by 12 weeks
Antegrade Nailing
551 cases (reamed)
1 union: 93.6%
2 union: 98.9%
Mal-alignment minimal
Distal 1/3 fxs had increased change of angulation
Wolinsky et al. , J. Trauma, 1999
Ostrum et al., J Orthop Trauma, 1998

23. Complications Femoral Bursting Technical error Other factors
Stiff nail
Radius of curvature mismatch “longitudinal jamming”
Eccentric entry points
Increase hoop stresses in proximal fragment
Large proximal fragment
Small fragment decreases hoop stresses

24. Complications Ways to Avoid Femoral Bursting
Obtain good starting portal
Prevent “longitudinal jamming”
Enlarge the IM canal
Nail diameter less than canal diameter
Canal reamed to a larger diameter than nail
Advent of static locking
No need to risk forcing a tight nail into a small canal

25. Complications Malreductions (Pushing the envelop) End segments
Potential for deformity
Malreduction
Instability of the nail
fixation in short segment
Eccentric reaming
Malrotation
External Rot.
Patients hate it

26. Complications Deep IM infection Prominent HW HW requiring removal
Hip pain
Knee pain
Need for secondary surgery for union

27. Having said all this: What about Retrograde Femoral Nail
Relative Indications
Ispilateral femur and tibia fxs
Supracondylar or distal third fxs
Bilateral
Polytrauma
Obesity
Associated femoral neck fracture and/or acetabular fracture
OR if you are Bob Ostrum fixing a femur fracture

28. Summary
Intramedullary nail is the BEST method of fixation for femoral shaft fractures
ANTEGRADE nailing tried and tested
Interlocking extends indications for treatment
Proximal and distal segments
Can be technically demanding
Many nail options therefore need a good preoperative plan
IM Reaming
Advantages
Improves Biomechanics, Improves Insertion Ease, Stimulates Healing
Disadvantages (REAL and must be remembered)
Pulmonary Injury, Increase Necrosis, Devitalized Bone, Cortical Remodeling

29. Antegrade vs Retrograde
The femur shaft fx does not know or care what direction you place the IM Nail…
But the hip and the knee surely do!

30. Thank You