Anatomy Reconstruct Of Anterior Cruciate Ligament(ACL) By Dual-source Computed Tomography(DSCT)

Objective1.To attempt to reconstruct femoral and tibial original footprint ofanterior cruciate ligament (ACL) by dual-source computed tomography (DSCT)three-dimensional reconstruction technique, make a conclusion, and try toprovide more comprehensive, reliable and representative theoretical basis forclinical personalized anatomy double-bundle reconstruction by measuring thefootprint geometry parameters of ACL.2. Femoral, try to establish a three-point-two-angle‘positioning system which is particularly applicable to thepersonalized anatomy double-bundle reconstruction of ACL under arthroscopy,to provide practical basis for clinical ACL personalized anatomy reconstruction.3.Tibial, DSCT three-dimensional reconstruction technique can be used forpostoperative singial and double bundle tunnel positioning evaluation, make aconclusion, and try to help surgery to improve operative scheme. Methods1.Fifty-five volunteers, including32males and23females aged20-50years oldwith average age of28years, were scanned by DSCT, and original data wereprocessed to64-slice spiral CT workstation (GE，Volume Share2-AW4.4version). Lateral wall of femoral intercondylar notch and tibial plateau werereconstructed. Original footprint of ACL was observated and painted. Femoral, the areas of original footprint of anteromedial bundle (AMB) and posterolateralbundle (PLB)、 length and width、footprint angle (FA)、distance between twocenters of AMB and PLB、the shortest distances to the distal margin of thearticular cartilage(DDCM) and the shortest distances to the posterior margin ofthe articular cartilage (DPCM) were measured. Tibial, footprint areas, footprintlength and width and the average geometric midpoint insertion for the ACLlocated on the tibial plateau were measured.2. Preoperative,30knees from30patients who planned to double-bundle reconstructed were scanned by DSCT.Lateral wall of the intercondylar notch and the ACL femoral footprint werereconstructed, and the three-point-two-angle‘positioning system was used forpreoperative plan. Intraoperative, femoral tunnels positioning was achievedaccording to the measured data of preoperative plan. Postoperative,30double-bundle reconstructed knees were scanned by DSCT again, and lateral wallof the intercondylar notch and the ACL femoral tunnels were achieved. Comparethe position relations between the measured data of preoperative plan and femoraldouble-bundle tunnels positioning.3. Over the same period,30singal-bundlereconstructed knees were scanned by DSCT. Lateral wall of the intercondylarnotch and tibial plateau were achieved. Compare the areas of recovery raterelations between the singal-bundle and double-bundle tunnels positioning, andevaluate singal-bundle and double-bundle tunnels positioning in tibial plateau.Results1. All ACL femoral and tibial footprints were successfullyreconstructed in110knee joints, which were relative protruding, plain, irregularin shape and completely different areas on the image. The femoral footprintparameters comparison: Differences were not statistically significant fromside-to-side in original footprint length and width,footprint angle, the shortestdistances to the distal margin of the articular cartilage and the areas of footprint （P>0.05）. Differences were statistically significant in the areas ofAMBfootprint, the distance from AMB center to PLB, the shortest distances to thedistal margin of the articular cartilage between males and females（P<0.05）.Differences were statistically significant in the shortest distances to the posteriormargin of the articular cartilage not only in side to side, but also in differentgende（rP<0.05）.2. The tibial footprint parameters comparison: Differences werestatistically significant in the mean area of tibial footprint of ACL betweendifferent gender: male:(200.99±30.42) mm~2, female:(170.30±26.94) mm~2（p=0.000）. Differences were statistically significant in the mean width of tibialfootprint of ACL between different gender: male:(9.25±1.56) mm, female:(8.30±1.46) mm（p=0.002）. Differences were not statistically significant in themean length of tibial footprint of ACL between different gender:male:(14.00±1.76) mm, female:(13.63±1.65) mm（P=0.278）. Comparison of theaverage geometric midpoint insertion for the ACL was located on the tibialplateau in sagittal and frontal reconstructions. Sagittal: male:（48.35±6.13)%,female:（47.53±4.34)%（P=0.689）. Frontal:male:(49.70±2.37)%, female:（49.00±2.68)%（P=0.070）. Differences were not statistically significant in theaverage geometric midpoint insertion for the ACL located on the tibial plateau indifferent gender.2. On the lateral wall of femoral intercondylar notch, Three-point-two-angle‘positioning system we developed can totally define anddescribe the double-bundle insertions and just be competently applied inanatomic ACL reconstruction with arthroscopic technique which was evidencedby later clinical used and postoperative tunnel evaluation.3. Postoperative, theaverage area recovery rate of AMB is (32±10)%, PLB is (38±8)%. The arearecovery rate of Double-bundle (70+16)%significantly greater than single-bundle (53±18)%(P=0.020). Conclusions1. ACL femoral and tibial footprint can be clearly reconstructed with DSCT three-dimensionalreconstruction technique.2. We can provide more comprehensive, reliable andrepresentative theory basis for clinical personalized anatomy double-bundlereconstruction by measuring the footprint geometry parameters of ACL whichwas reconstructed by dual-source computed tomography three-dimensionalreconstruction technique.3.ACL femoral and tibial natural footprints are differentfrom one another which indicates the need of individualized reconstruction inorder to restore the anatomy in maximum.4.The three-point-two-angle‘positioning system postulated by us is just suitable for anatomic ACLreconstruction with arthroscopy.5. DSCT three-dimensional reconstructiontechnique can be used for postoperative tunnel positioning evaluation and to helpsurgery to improve operative scheme.6.Compared with single–bundlereconstruction, individualized double-bundle reconstruction is more able torestore the anatomy in maximum.