2. Treatment of femoral neck fractures INTERNAL FIXATION –In biologic ‘young’ patients (< 60-80 yr) ARTHROPLASTY –In biologic ‘old’ patients (> 60-80 yr)

3. Results of fixation of femoral neck fractures 35% RE-INTERVENTION RATE IN DISPLACED # Non-union Avascular necrosis Loss of fixation

4. Fracture healing of femoral neck fractures GOALS: Preserve the remaining blood supply Provide the stability necessary for revascularisation Provide the stability necessary for primary osteonal reconstruction MEANS: Anatomical reduction Stable internal fixation

5. Why do implants fail? multiple parallel screws or pins: PRO’S: Dynamic Minimal invasive CON’S: No angular stability No rotational stability Stability relies on the three- point fixation method and is dependant on exact screw placement High total implant volume

6. Why do implants fail? sliding hip screw devices: PRO’S: Angular stability Dynamic CON’S: No rotational stability –During insertion –After insertion –With or without ‘anti-rotation’ screw High implant volume LABILE UNSTABLE

7. Can we make a better implant?

9. GANNET Gannet nail & side wings Impaction anchors Gannet plate

10. CHARACTERISTICS: Rotational stability Angular stability Dynamic compression Impaction locking Minimal invasive High load bearing surface Cannulated technique Simple instrumentation

11. ROTATIONAL STABILITY: Sidewings on blade Impaction anchors ANGULAR STABILITY: Sliding barrel plate Dynamic compression

12. IMPACTION LOCKING: Locking of the Gannet nail in the femoral head 1.Prevents perforation 2.Prevents backing out 3.Additional rotational stability 4.Augmented by bone impaction

13. MINIMAL INVASIVE Low implant volume: GANNET: 920 mm 3 DHS: 1975 mm 3

14. MINIMAL INVASIVE Low frontal area: GANNET: 31 mm 2 DHS: 133 mm 2

15. HIGH LOAD BEARING SURFACE: GANNET: 338 mm 2 DHS: 221 mm 2

16. CANNULATED: 3.0 mm guide wire

17. SIMPLE INSTRUMENTATION

18. GANNET (DLBP) loading tests

19. GANNET (DLBP) static deformation test

20. GANNET fatigue test

21. GANNET anchor expansion test

22. GANNET push in test

23. GANNET (DLBP) cut out test

24. GANNET (DLBP) rotation test

25. Guide pin insertion

26. Stepped cannulated drilling

27. Introducer setting

28. Introducer/implant assembly

29. One step insertion

31. GANNET pilot study No technical complications No general complications Fracture healing 23/25 Avascular necrosis 1/25 Non union 1/25

32. GANNET pilot study REINTERVENTION RATE: 2/25 Undisplaced fractures (n=8): 0/8 Displaced fractures (n=17): 2/17

33. GANNET conclusions Fast Streamlined Targeted Fold wings in pursuit