Objective:Anterior cruciate ligament injury is the most common type of knee joint ligament injury.Anterior cruciate ligament reconstruction has a high failure rate,with bone tunnel abnormalities as the most significant factor in these failures.Digital orthopedic technology can effectively develop implementation plans for the revision,thus increasing the success rate.This study aims to develop a surgical plan for anterior cruciate ligament revision by employing multiplanar reconstruction(MPR)for measuring bone tunnel position and diameter,and simulating bone tunnel creation via 3D printing preoperatively. Methods:A total of 12 patients who underwent anterior cruciate ligament revision at the Third Xiangya Hospital of Central South University between 2014 and 2021 were retrospectively studied.The data included patient demographics,preoperative formulated knee joint 3D printing models,and preoperative knee CT scans.The study measured the bone tunnel's diameter and position to guide the establishment of revision bone tunnels during surgery,reassessed the postoperative bone tunnels,and evaluated knee joint functional scores[including International Knee Documentation Committee Knee Evaluation Form(IKDC)score,Lysholm score,and Tegner exercise level score]. Results:Preoperative measurements revealed suboptimal femoral tunnels positions in 4 patients and tibial tunnels positions in 2 patients.MPR and 3D printing technology were used to guide the establishment of a new bone canal during surgery,and postoperative measurements were satisfactory for all patients.Preoperative measurements demonstrated the interclass correlation coefficient for femoral tunnels and tibial tunnels diameters were 0.843(P<0.05)and 0.889(P<0.001),respectively.Meanwhile,the intraclass correlation coefficient were 0.811(P<0.05)and 0.784(P<0.05),respectively.The intraoperative diameter of femoral and tibial tunnels showed excellent correlation with postoperative CT measurements,with intraclass correlation coefficient values of 0.995(P<0.001)and 0.987(P<0.001),respectively.All bone tunnel positions were within the normal range.At the final follow-up,knee joint function scores in all 12 patients improved significantly compared to pre-surgery(P<0.001),and the reoperation rate was zero. Conclusion:MPR and 3D printing technology can accurately measure the parameters of reconstructed anterior cruciate ligament bone tunnels.Personalized revision plans for patients with reconstruction failure enhances the success rate of revision surgery and improves patient prognosis.

OBJECTIVE：To i mprove the transfer rate and purity of oleanolic acid and ursolic acid in total triterpenoids from Ligustrum lucidum ，so as to optimize the purification technology. METHODS ：Oleanolic acid and ursolic acid were used as representative components of total triterpenoids ，and their contents were determined by HPLC. The determination was performed on Thermo BDS Hypersil C 18 column with mobile phase consisted of methanol- 0.02％ ammonium acetate solution （80∶20，V/V）at the flow rate of 1.0 mL/min. The detection wavelength was set at 210 nm，and column temperature was 30 ℃. The sample size was 20 μ L. In single factor tests，using transfer rate of oleanolic acid and ursolic acid as index ，the effects of water precipitation temperature and time ，the amount of redissolved ethanol on the purification technology was investigated ；using transfer rate and purity of two components as indexes ，the effects of the amount of activated carbon and volume fraction of crystallization ethanol were investigated. Based on it ，using the amount of redissolved ethanol and activated carbon ，volume fraction of crystallization ethanol as factors ，Box-Behnken response surface methodology was used to optimize the purification technology ，and validation tests were performed. RESULTS ：The optimal purification technology was adding 4-fold（mL/g，the same below ）water in L. lucidum concentrated solution ，placing for 2 hours at 0 ℃（water precipitation ）；adding 1-fold ethanol to dissolve （redissolution）； adding 4％ activated carbon （edulcoration）；finally adding water to adjust the volume fraction of ethanol to 80％，placing at 4 ℃ for 12 hours（crystallization），centrifuging and drying. The results of 3 times of validation tests showed that the transfer rates of oleanolic acid and ursolic acid in total triterpenoids prepared by optimized technology were 61.11％ and 65.78％，the purities of them were 53.44％ and 19.79％，and RSDs were both lower than 3％. CONCLUSIONS ：The optimized purification technology has high extraction efficiency and simple operation ，which can be used for industrial production of purification of total triterpenoids from L. lucidum and the development of corresponding preparations.