1. Nahhas, M., Turcotte, R.E. and Isler, M.
RADIOLOGICAL FOLLOW-UP OF DISTAL FEMORAL ENDOPROSTHESES FOR TUMOR RESECTION
Nahhas, M., Turcotte, R.E.
and Isler, M.

3. Radiological Follow-up of Distal Femoral Endoprostheses
Choice of the reconstruction method depends on many variables
function
complications
longevity of the implant (rate of revision)
radiological follow-up

4. Radiological follow-up of distal femoral endoprostheses
complications of massive oncological endoprosthetic implants
(infection)
recurrence
aseptic loosening
fracture
bushing wear

5. Radiological follow-up of distal femoral endoprostheses
Turner et al, OCNA #13, 1982
analyzed complications of early rotating hinge implants
fractures of tibial bearing component 5/200
misalignment or lack of tibial support
stress concentration
corrected by design changes

6. Radiological follow-up of distal femoral endoprostheses
Rotating hinge vs fixed hinge
decreased constraints to decrease
loosening
bushing failure
generation of metallic debris
Polyethylene bearing surfaces
increased debris?

7. Radiological follow-up of distal femoral endoprostheses
GOAL
to determine the rate of complications
consequences
longevity
inform the surgeon and patient regarding choice of reconstruction options

8. Radiological follow-up of distal femoral endoprostheses
Material and Methods:
prospective orthopedic oncology database
32 patients had received a distal femoral massive endoprosthesis
years 1990 to 2004

9. Radiological follow-up of distal femoral endoprostheses
Material and Methods:
identical implant (KMRS)
identical technique (cemented)
Average follow-up 3.8 years (46m)
MSTS (ISOLS) method of radiologic evaluation

10. Radiological follow-up of distal femoral endoprostheses
MSTS (ISOLS) method
aseptic loosening (bone remodelling)
aseptic loosening (interface)
anchorage (loosening or fracture)
implant body problems
implant articulation problems (wear)
extra-cortical bone bridging

11. Radiological follow-up of distal femoral endoprostheses

13. Radiological follow-up of distal femoral endoprostheses stress shielding

14. Radiological follow-up of distal femoral endoprostheses
Results (N = 32)
excellent bone remodeling in 31
no change from immediate postop
excellent interface in 32
no radio-lucent line
excellent anchorage in 31
adequate cement mantle, no change

15. Radiological follow-up of distal femoral endoprostheses
Results (N=32)
implant body problems: none
Implant Articulation
excellent in 30 (no change)
good in 2 patients (<2mm decrease)

16. Radiological follow-up of distal femoral endoprostheses
Results N=32
Extracortical bone bridging
excellent in 6 patients, good in 4, fair in 11 and poor in 11
*beaded surface at interface

17. Radiological follow-up of distal femoral endoprostheses
Turner et al, 1982
analyzed complications of early rotating hinge implants
fractures of tibial bearing component 5/200
none in our series
no significant signs of polyethylene wear being associated with loosening

18. Radiological follow-up of distal femoral endoprostheses
Eckardt et al, 1997
N=24, F-up median 5.8y
stress shielding proximal osteolysis
osteolysis at the proximal junction as early sign of loosening (54%) at 42 m
17% radiological loosening
8% revision

19. Radiological follow-up of distal femoral endoprostheses
Malawer, 2002
median f-up 7.8y
revised for aseptic loosening 5.4%
hardware failure 5.4% (polyethylene)

20. Radiological follow-up of distal femoral endoprostheses
Chao et al 1996
N=30, F-up median 3.5y
similar results to ours, same implant
extracortical bone bridging > 25% in 18 (60%)

21. Radiological follow-up of distal femoral endoprostheses
Our study
3.8y follow-up
no revisions done or planned
bone bridging > 25% in 65%
excellent radiological results

22. Radiological follow-up of distal femoral endoprostheses
Discussion
descriptive study of radiological complications in a prospective series using a uniform reconstruction method
certain conclusions can be drawn regarding medium and long term outcome

23. Radiological follow-up of distal femoral endoprostheses
Conclusion : Overall results in this series suggests a low rate of complications can be expected from the radiological standpoint when using massive endoprostheses for the reconstruction of the distal femur after oncological resection

24. Radiological follow-up of distal femoral endoprostheses
this study adds to the existing evidence
scientific data regarding the outcome for an implant allows the surgeon to make an evidence based choice

25. Radiological follow-up of distal femoral endoprostheses
Thank you for your attention