2017 ISAKOS Biennial Congress ePoster #1170

 

Comparison Between Two Different Interference Fit Femoral Fixation Devices For Acl Reconstruction With Doubled Achilles Tendon Graft:A Biomechanical Analysis On Sheep Specimen

Xuezhen Shen, PhD, Beijing CHINA
Feng Qu, MD, Beijing CHINA

Department of Orthopaedics, Chinese PLA General Hospital, Beijing 100853, China, beijing, CHINA

FDA Status Cleared

Summary

To test the biomechanical properties of self-designed biological cortical bonepress-fit bolt fixation for the reconstruction of anterior cruciate ligament (ACL).

Abstract

Methods: 16 fresh goat knee joint specimen been divided into two groups; 5 normal knee joint complex. Soft tissue around the knee joint specimens were removed and us self-designed 6mm diameter biological cortical bonepress-fit bolt and diameter of 7mm absorbable interference screw to fix the goat double Achilles tendon reconstructing the anterior cruciate ligament respectively. The fixed point is in distal of bone tunnel for femoral, in the proximal of bone tunnel for tibial, both are fixed near joint line, only the anterior cruciate ligament survived of the normal knee joint complex. The reconstructed samples were fixed on the biomechanical machine, the maximum failure load (MFL),yield load(YL) and stiffness were determined. Record the maximum displacement of specimens in first times, thirtieth times, 100th times, 500th times and 1000th times of the system and the failure mode in cyclicloading test. The data were statistically analyzed and compared the biomechanics index of biological cortical bonepress-fitbolt ,absorbable interference screw and normal anterior cruciate ligament ,analysis the biomechanical properties of self-designed biological cortical bonepress-fit bolt fixation for the reconstruction of anterior cruciate ligament (ACL).

Results

In femoral, YL ofcortical bonepress-fit bolt group are greater than the interface screw group, the difference was statistically significant (P <0.05), stiffness of cortical bonepress-fit bolt group is greater than the interface nail group, the difference is not statistically significant (P>0.05). There are no statistical difference in the maximum displacement of the circulatory system in first times, 30 times, 100 times, 500 times, 1000 times is not significant (P>0.05)in two groups. In tibial, YL of cortical bonepress-fit bolt group are greater than the interface screw group, the difference was statistically significant (P <0.05), stiffness of cortical bonepress-fit bolt group is greater than the interface nail group, the difference is not statistically significant (P>0.05). The difference of maximum displacement between the two groups in the 100th, 500, 1000 cycles is statistically significant (P<0.05); while there is no significant difference in the first times, 30th cycles (P>0.05).
Conclusion:The mechanical performances like biggest failure load and failure load, the stiffness, cortical bonepress-fit bolt reconstruction of ACL are better than absorbable screw interface screw in tibial and femoral side.It is a good choice to usecortical bonepress-fit bolt in anterior cruciate ligament reconstruction fixation.