Artikel
A novel implant-free femoral pull-press-fixation for ACL reconstruction
Suche in Medline nach
Autoren
-
Sebastian Kwisda
- MH Hannover, Medizinische Hochschule Hannover, Unfallchirurgie, Hannover, Germany
-
Antonios Dratzidis
- Annastift, MHH, Orthopädie, Hannover , Germany
-
Mohamed Omar
- Medizinische Hochschule Hannover, Unfallchirurgische Klinik, Hannover, Germany
| Veröffentlicht: | 10. Oktober 2016 |
|---|
Gliederung
Text
Objectives: Extracortical fixation techniques in anterior cruciate ligament reconstruction bear the risk of tunnel enlargement, while close-to-aperture fixations often show lower failure loads. The purpose for this study was to investigate the biomechanical properties of a novel implant-free femoral combination of an extra-cortical and close-to-aperture fixation.
Methods: Quadrupled human cadaveric semitendinosus tendons were fixed to 30 porcine femorae with either a cannulated interference screw (IF), an implant-free post fixation (SKN), an EndoButton fixation (EB) or a novel pull-press fixation (PP). Specimens were cyclically loaded 20 times between 20-60 N followed by 500 cycles with 60- 200 N, followed by a load to failure test with 1 mm/sec.
The tests were recorded with a digital video camera.
Constructs were photo-optically marked at intervals of 10 mm starting at the ridge of the femoral drill hole. One marker was located in the bone and 3 markers within the tendons, with a distance of 10 mm between each marker. Markers were used to investigate length changes within the tendon and to analyze changes between tendon and bone.
Results: The difference in the mean elongation of the tendons in the groups during the 500 cycles between 60-200 N was not significant (p>0,05). The mean maximum load to failure was significantly higher (p<0,01) in the PP- (710±64N), IF- (634±71N) and EB-group (754±72N)compared to in the SKN-group (511±52N). There was no significant difference between the PP- and the EB-group and also no significant difference between the PP and the IF-group. The load to failure in the EB-group was significantly higher (p<0,01) than the IF-group. Stiffness of the constructs in the PP-group was significantly higher (176±71 N/mm) compared to 84±26 N/mm in the SKN-group. There was no significant difference in stiffness in the other groups. The analysis of the photo-optical markers confirm the biomechanical results.
Conclusions: This study indicates comparable biomechanical properties of a novel implant-free femoral pull-press fixation to conventional extracortical and close to aperture implant-techniques and superior properties to conventional implant-free techniques in terms of cyclic elongation, stiffness and maximum load to failure. Clinical studies will have to confirm the biomechanical results.
