DYNAMIC HIP SCRE SURGERY FOR INTERTROCHANTERIC FRACTURES

1. DYNAMIC HIP SCREW
DR ANURAG MITTAL
ORTHO
UCMS

2. INDICATION
• Stable intertrochanteric fracture till 2.1 –study by evans and another
by Hornby-non operative vs operative
• Low complication ,mortality rate,pain, leg swelling, sores –same in both
• But shorter hospitalization
• Better restoration of normal anatomy
• Ability to live independently
• Basicervical neck of femur # with derotation screw
• Unstable # with
• TSP
• Axial dynamic compression plate
• IHS

5. TSP

6. Biaxial compression plate

7. IHS

8. Principle
• Controlled collapse
• Dynamic action reduces incidence of screw cut
out and penetration of screw into hip joint

9. Procedure

10. Position

11. Reduction
• Undisplaced #-no reduction,slight IR
• Displaced#-
• extension ,
• Abduction-corrects varus
• IR –”screw home” the distal fragment
• Evaluation
• #displacement
• Neck shaft angle
• Anteversion
• Femoral shaft ‘sag’
• Rotation checked clinically

12. Lateral approach to
the proximal femur

13. Guide pin insertion
• For 135 angled plate
• If higher angled plate-entry
moved 5 mm distally for 5
degree increase

14. ANGLE GUIDE

15. VARIABLE ANGLE GUIDE

17. • Why 135 ideal??
• Hip joint resultant force-159-
difficult insertion/cut out
• 130-high bending load
• Influence of nail plate angle on
bending moment: Larger angle
results in smaller moment
because of shorter distance (d);
conversely, smaller angle results
in larger moment because of
longer distance

18. TIP APEX DISTANCE
• Should be <25mm
• Tip of screw should lie under 10
mm of subchondral bone
• Screw should ideally lie in centre
on ap and lateral views
• Superior and anterior location
avoided-cut out

19. Lag screw length
• Measuring guide used
• Tip extension and immediate telescoping
must be taken into account

20. Short vs long barrel
• <85 mm—short barrel
• >=85 mm—standard barrel
• WHY??
• Thread length-22mm
• Recommended sliding -25 mm(min 10 mm)
• Standard barrel length-38 mm(short-25 mm)
• So 22+25+38=85mm

21. COMPONENTS
SHORT BARREL
LONG BARREL
TRIPLE REAMER

25. Implant insertion and fixation
• Long vs short side plate
• More dissection
• Complicate future surgery
• no improvement in proximal purchase
• Inherent stability of fracture/reduction not altered
• Reduces tensile forces on prox two screws but no additional protection
• Same rate of failure

26. Keyed system

31. • Traction released
• Angled plate acts as an aid to
reduction
• Intraop prox displacement of
femoral shaft along the plate
before screw insertion
• Post op as lag screw collapses into
the barrel by impaction
• Compression screw-also
prevents postop hip screw barrel
disengagement

32. Complication

33. •