Distal Third Femoral Shaft Fracture: Antegrade vs. Retrograde Nailing Michael Zlowodzki MD University of Minnesota Department of Orthopaedic Surgery

HPI  71 y/o was working on a ladder and fell  Ambulatory without assistive devices prior to injury  decreased dp pulse when compared to LLE. dopplerable. ABI 1.2  h/o CABG s/p bypass, AV replacement, A flutter, DM  On Coumadine  INR on presentation: 2.7

DEFINITIVE TREATMENT OPTIONS ?

TREATMENT OPTIONS  Antegrade nailing (Piriformis fossa)  Antegrade nailing (Trochanteric entry)  Retrograde nailing  Submuscular plating  (External fixation)

ANTEGRADE (Piriformis) vs. RETROGRADE NAILING: Current evidence  2 RCTs  1 non-randomized comparative study

POTENTIAL REASONS NOT TO DO ANTEGRADE NAILING  Multiply-injured patients  Spinal injuries  Fractures of the hip, pelvis or acetabulum  Bilateral injuries  Obesity

 54 retrograde (all reamed) –1 nonunion  46 antegrade (all reamed) –All healed  10 mm nail in all cases –prolonged time to union associated with a nail-to- canal diameter difference with either insertion technique

 N=94 antegrade (57% unreamed, 81% static) –89% healed –10% hip pain & 9% knee pain (in patients with no hip and knee injuries)  N=104 retrograde (89% unreamed, 72% static) –88% healed –4% hip pain & 36% knee pain (Avg f/u: 23 months) (in patients with no hip and knee injuries) HIGH NONUNION RATE, BUT MAJORITY UNREAMED

 69 fractures randomized (f/u: 65/69)  All reamed and statically locked  Toe-touch weight bearing until callus  All healed  3/35: Hip HO after antegrade nailing  3/30: Knee hemarthrosis (perc. Arthrocentesis done)

ROTATIONAL ALIGNMENT IN COMMINUTED FXS (Winquist 3 & 4):  Assessed with CT  Antegrade nailing: 3 of 18 (17%)  Retrograde Nailing: 5 of 15 (33%) (+ 5/30 shortened by avg. of 12 mm) Tornetta et al. Antegrade or retrograde reamed femoral nailing. A prospective, randomised trial. JBJS Br. 2000; 82(5), 652-4

 “…nailing without a traction table made length and control of rotation more difficult, as evidenced by the superior reductions achieved in the antegrade group”  “To avoid this problem we advise that the distal jig be used to rotate the nail with the leg and crosslocking at the proximal end be carried out first.” Tornetta et al. Antegrade or retrograde reamed femoral nailing. A prospective, randomised trial. JBJS Br. 2000; 82(5), 652-4

RETROGRADE NAILING: Proximal Locking

 Mechanical reason: –Avoid stress risers (Highest stress in subtroch area)  Anatomical reason: –Avoid neurovascular structures ABOVE LESSER TROCHANTER

 Highest tensile and compressive stresses in subtrochanteric area  14 times higher compressive stresses in one- leg stance: 44 N/mm 2 (compared to 2-leg stance)  24 times higher tensile stresses in one-leg stance: 36 N/mm 2 (compared to 2-leg stance)

 60 CADAVERS DISSECTED  Branches of femoral artery: 10 cm below piriformis fossa (All branches at least 10 cm below)  Branches of femoral nerve: 4 cm below piriformis fossa (On average 4 cm +/- 1.4)

Branches of the femoral nerve proximal to the lesser trochanter Riina et al. J Orthop Trauma, Volume 12(6).August

RETROGRADE NAIL: ENTRY POINT

 26 cadaver 6 mm anterior to PCL 3 mm medial

 11 cadaver 12 mm anterior to PCL Midline in coronal plane

CONCLUSION: ANTEGRADE vs. RETROGRADE NAILING - ALWAYS REAM !!! - EQUAL UNION RATES - HIP PAIN VS. KNEE PAIN

Worst case scenario: rIMN Ricci et al. Retrograde versus antegrade nailing of femoral shaft fractures. JOT 2001; Mar-Apr;15(3):161-9.

MY FIXATION PREFERENCE ORDER FOR THIS CASE 1.Antegrade piriformis fossa nail 2.Submuscular locking plate 3.Antegrade trochanteric entry nail 4.Retrograde nail 5.External fixation