ObjectiveThis study aims to investigate the dynamic changes in general body parameters, blood glucose, and blood lipid profiles in obese cynomolgus monkeys, exploring the correlations among these parameters and providing a reference for research on the obese cynomolgus monkey model. Methods30 normal male cynomolgus monkeys aged 5 - 17 years old (with body mass index < 35 kg/m² and glycated hemoglobin content < 4.50%) and 99 spontaneously obese male cynomolgus monkeys (with body mass index ≥35 kg/m² and glycated hemoglobin content < 4.50%) were selected. Over a period of three years, their abdominal circumference, skinfold thickness, body weight, body mass index, fasting blood glucose, glycated hemoglobin, and four blood lipid indicators were monitored. The correlations between each indicator were analyzed using repeated measurement ANOVA, simple linear regression, and multiple linear regression correlation analysis method. Results Compared to the control group, the obese group exhibited significantly higher levels of abdominal circumference, skinfold thickness, body weight, body mass index, and triglyceride (P＜0.05). In the control group, skinfold thickness increased annually, while other indicators remained stable. Compared with the first year, the obese group showed significantly increased abdominal circumference, skinfold thickness, body weight, body mass index, triglyceride, and fasting blood glucose in the second year(P＜0.05), with this increasing trend persisting in the third year (P＜0.05). In the control group, the obesity incidence rates in the second and third years were 16.67% and 23.33%, respectively, while the prevalence of diabetes remained at 16.67%. In the obese group, the diabetes incidence rates were 29.29% and 44.44% in years 2 and 3, respectively. Among the 11-13 year age group, the incidence rates were 36.36% and 44.68%, while for the group older than 13 years, the rates were 28.13% and 51.35%. Correlation analysis revealed significant associations (P＜0.05) between fasting blood glucose and age, abdominal circumference, skinfold thickness, body weight, and triglyceride in the diabetic monkeys. Conclusion Long-term obesity can lead to the increases in general physical indicators and fasting blood glucose levels in cynomolgus monkeys, and an increase in the incidence of diabetes. In diabetic cynomolgus monkeys caused by obesity, there is a high correlation between their fasting blood glucose and age, weight, abdominal circumference, skinfold thickness, and triglyceride levels, which is of some significance for predicting the occurrence of spontaneous diabetes.

Objective:To investigate the relationship between anterior tibial translation (ATT) and bony morphology around the knee after anterior cruciate ligament (ACL) injury.Methods:A total of 67 patients diagnosed with acute ACL injury without any meniscal lesions were enrolled in this study between September 2019 and August 2020. Preoperative magnetic resonance imaging (MRI) scans were used to measure the ATT of the lateral compartment, and bony morphology was assessed by measuring lateral femoral condyle (LFC) length, LFC height, lateral tibial plateau (LTP) length, LTP slope and by calculating the following ratios: LFC ratio (LFC length/LFC height), knee extension ratio (LFC length/LTP length), and knee flexion ratio (LFC height/LTP length). The status of the anterolateral ligament (ALL) was assessed by preoperative MRI scans and classified as completely injured (44 patients), partially injured (19 patients), or intact (4 patients). The ATT was compared between patients with completely injured ALL and those with partially injured or intact ALL. Pearson correlation analysis between the ATT and each bony variable was performed in ALL-completely-injured patients and ALL-partially-injured or intact patients.Results:Of the 67 patients, 33 were male and 34 were female, with a mean of age 31.7±9.7 years (range 15-47 years). The average of time interval between ACL injury and MRI examination was 26.0±22.0 days (95% CI: 20.7, 31.4 d). The ATT of the lateral compartment was 5.6±4.0 mm (range, -4.9-16.2 mm), the average of LFC length was 37.3±2.5 mm (range, 30.5-43.2 mm), the average of LFC height was 37.4±3.6 mm (range, 30.6-46.3 mm), the average of LTP length was 46.9±4.1 mm (range, 39.0-56.8 mm), the average of LTP slope was 6.3°±3.1° (range, -3.7°-11.6°), LFC ratio was 100.4%±8.1% (range, 84.1%-119.0%), knee extension ratio was 80.0%±5.8% (range, 66.1%-96.3%), and knee flexion ratio was 80.0%±6.0% (range, 66.4%-93.8%). The ATT was greater in patients with completely injured ALL than in patients with partially injured or intact ALL (6.4±4.3 mm vs. 3.9±2.8 mm, t=2.52, P=0.014). The ATT was negatively correlated with LFC height ( r=-0.43, P<0.001) and LTP length ( r=-0.35, P=0.004) and was positively correlated with LFC ratio ( r=0.48, P<0.001), knee extension ratio ( r=0.36, P=0.003), and LTP slope ( r=0.29, P=0.018). All these correlations were still statistically significant in patients with complete ALL injury ( P<0.05), but were no significant in patients with partial ALL injury or intact ALL ( P>0.05). Conclusion:Bony morphology of the distal femur and proximal tibia was associated with ATT after ACL injury. Such an association was more dramatic in patients with a complete ALL injury.

Objective:To evaluate the clinical, radiological and arthroscopic outcomes after surgical repair for chronic lateral meniscus posterior root (LMPR) avulsion combined with anterior cruciate ligament (ACL) reconstruction.Methods:From July 2015 to June 2017, a total of 33 patients who underwent transtibial pull-out suture repair for chronic LMPR avulsion combined with anatomic single-bundle ACL reconstruction with hamstring graft were retrospectively reviewed. There were 30 males and 3 females with an average age of 27.7±7.5 years (range 17-45 years) and a mean BMI of 25.2±3.7 kg/m 2 (range 19.4-36.7 kg/m 2). All patients were available for at least two years of follow-up. A second-look arthroscopy was performed to evaluate the healing status of the repaired meniscus. Subjective knee function was assessed through Lysholm and Tegner scores. Objective knee stability was evaluated using KT-1000 arthrometer side-to-side difference (SSD) and pivot shift test under anesthesia. The tibiofemoral relationship was evaluated by anterior tibial subluxation (ATS) measured on axial MRI. Between patients with preoperative ATS ≥6 mm (18 patients in the ATS positive group) and <6 mm (15 patients in the ATS negative group), the postoperative ATS and the reduction of ATS was also compared. Results:After a mean follow-up of 27.5±4.0 months (range 24-39 months), the LMPR avulsion completely healed in 23 (70%) cases, partially healed in 9 (27%) cases, failed to heal in 1 (3%) case on second-look arthroscopy. The Lysholm score was increased from 60.4±13.6 to 82.7±11.1 at 1 year and to 91.4±9.1 at 2 years operatively ( F=155.996, P<0.001). The Tegner score was increased from 3(2, 5) to 4(3, 5) at 1 year and 6(4, 6) at 2 years postoperatively (χ 2=47.791, P<0.001). The KT-1000 SSD was decreased from 9.1±3.3 mm to 2.0±1.7 mm ( t=11.197, P<0.001). The result of pivot shift test was also improved (10 grade I, 20 grade II, 3 grade III, preoperatively vs 30 grade 0, 3 grade I, postoperatively, U=5.161, P<0.001). The ATS was reduced from 5.7±3.9 mm to 3.5±3.2 mm ( t=3.530, P=0.001). However, there was no statistically significant decrease in the ATS of the ATS negative group ( t=0.400, P=0.695). The ATS of the ATS positive group was reduced from 8.7±1.8 mm to 5.0±3.3 mm ( t=4.765, P<0.001), and the ATS reduction of the ATS positive group was greater than that of the ATS negative group (3.7±3.3 mm vs 0.3±2.8 mm, t=3.115, P=0.004). Conclusion:In patients undergoing ACL reconstruction, the transtibial pull-out suture repair for chronic LMPR avulsion yielded meniscus healing rate of 97% with improved subjective knee function and objective knee stability and better restored the tibiofemoral relationship for patients with excessive ATS.

Objective:To explore the risk factors of primary anterior cruciate ligament (ACL) reconstruction failure.Methods:From November 2015 to May 2017, a total of 178 consecutive patients with clinically diagnosed non-contact ACL injury were treated and followed-up more than 2 years. Twenty-five patients (post-operative failure group) who underwent completely ruptured ACL graft confirmed by MRI, positive pivot-shift test, more than 5 mm side-to-side difference (SSD) measured by KT-1000 arthrometer, more than 5 mm static anterior tibial translation (ATT) measured on MRI were determined to be ACL reconstruction failure. They were matched in a 1∶2 fashion to 50 non-failure patients (post-operative non-failure group), who showed intact ACL graft 2 years after ACL reconstruction. The sex, age, body mass index (BMI), affected side, meniscal injury side, time from injury to surgery, KT-1000 SSD, pivot shift test under anesthesia, follow-up duration, posterior tibial slope (PTS) and ATT measured on the pre-operative weight-bearing whole leg radiographs between the two groups were compared using univariate analysis. Moreover, the predictors of ACL reconstruction failure were assessed by multivariable conditional Logistic regression analysis.Results:Post-operative failure group had a significantly higher PTS and ATT values than those in the post-operative non-failure group (17.21°±2.20° vs 14.36°±2.72°, t=4.395, P<0.001; 8.29±3.42 mm vs 4.09±3.06 mm, t=5.504, P<0.001). The sex, age, BMI, affected side, meniscal injury side, time from injury to surgery, KT-1000 SSD, pivot shift test under anesthesia, follow-up duration between the two groups showed no significant difference ( P>0.05). Multivariable Logistic regressions indicated that PTS≥17° ( OR=15.62, P=0.002) and ATT≥6 mm ( OR=9.91, P=0.006) were independent risk factors for primary ACL reconstruction failure. However, sex, age, BMI, meniscal lesions, degree of pivot shift test, KT-1000 SSD were not the independent risk factors. Conclusion:PTS≥17° and ATT≥6 mm could increase the risk of primary ACL reconstruction failure.

Objective To investigate the risk factors of J sign in patients with recurrent patellar dislocation, and to estab?lish a new grading system of J sign. Methods From January 2017 to August 2018, a consecutive case series of 111 recurrent pa?tellar dislocation patients were included in the present study. Among these patients, a total of 68 patients had positive J sign (J sign (+) group), and the remaining 43 patients had negative J sign (J sign (-) group). Caton index, Dejour classification, tibial tuber?osity?trochlear groove (TT?TG) distance and rotational parameters of the lower extremity (including femoral anteversion angle, ex?ternal tibial torsion angle and knee rotation angle) were measured to compare the differences of these parameters between the inter?vention group and control group. Furthermore, the risk factors of J sign were analyzed in detail. Meanwhile, a new grading system of J sign was introduced based on the extent and form of lateral patellar shift. Results The prevalence of J sign in recurrent patel?lar dislocation was 61.3% (68/111). Univariate analysis showed that femoral anteversion angle (t=3.376, P=0.001), knee rotation angle (t=4.886, P=0.001), TT?TG distance (t=3.177, P=0.002) and prevalence of patellar alta (χ2=9.809, P=0.002) were much high?er in the J sign (+) group, and the differences were statistically significant when compared with the J sign (-) group. Multivariate Logistic regressions demonstrated that increased femoral anteversion angle ( OR=1.118, P=0.012), enlarged knee rotation angle ( OR=1.178, P=0.016) and patella alta ( OR=3.229, P=0.040) were independent risk factors of J sign in patients with recurrent pa?tellar dislocation. Conclusion Increased femoral anteversion angle, enlarged knee rotation angle, and patellar alta were strongly associated with J sign. These factors may be independent risk factors of J sign in patients with recurrent patellar dislocation.

Objective To investigate the effects of excessive pre?operative anterior tibial translation (ATT) on post?opera?tive knee stability after anterior cruciate ligament (ACL) reconstruction. Methods From January 2016 to December 2016, a total of 348 patients with noncontact ACL injuries who underwent primary anatomic single?bundle ACL reconstruction were retrospec?tively analyzed. The hamstring autograft was used as the grafted tendon. The ATT relative to the lateral femoral condyle was mea?sured on pre?operative magnetic resonance imaging (MRI) scans. Among them, twenty patients (ATT positive group) who demon?strated>10 mm ATT distance were matched in a 1∶2 fashion to 40 control participants (ATT negative group) with<3 mm ATT dis?tance. All patients were followed for at least 2 years. The post?operative clinical outcomes, including the ATT distance, the KT?1000 side?to?side difference, and the pivot?shift tests were compared between the two groups. Results The ATT distance of the ATT positive group was 13.5±1.3 mm, which was significantly larger than that of the ATT negative group (2.5±1.4 mm) (t=45.435, P=0.013) pre?operatively. At 2?year follow?up, the ATT distance of the ATT positive group was 9.7±1.8 mm, which was significant?ly larger than that of the ATT negative group (0.9±1.6 mm) (t=49.655, P=0.011). Moreover, the KT?1000 side?to?side difference of the ATT positive group was 4.4±1.5 mm, which was also significantly larger than that of the ATT negative group (0.8±1.1 mm) (t=38.945, P=0.014). There was significantly difference in the pivot?shift test between the two groups (ATT positive group: 1 grade 0, 18 grade I, 1 grade II vs. ATT negative group: 39 grade 0, 1 grade I) (χ2=40.521, P=0.012). Conclusion Excessive ATT could not be completely restored to normal after isolated anatomic single?bundle ACL reconstruction. Compared to the ATT negative group, the ATT positive group has inferior knee stability at 2?year follow?up.

Objective To discover the relationship between the post?operative positive residual patellar J sign and the laxity of reconstructed medial patellofemoral ligament (MPFL) after MPFL reconstruction combined with tibial tubercle osteotomy (TTO). Methods A total of 39 consecutive recurrent patellar dislocation (RPD) adult patients who were performed MPFL recon?struction and TTO with more than 2 follow?up time were analyzed retrospectively in the present study. The patellar tracking of all the patients was evaluated and was classified into positive patellar J sign group and negative J sign control group during knee ac?tive flexion and extension at final follow up. The computed tomography (CT) examination was performed in all patients at 0°exten?sion of the knee. The patellar laxity index measured by patellar glide test (PGT) and the radiographic parameters (tibial tuberosity?trochlear groove distance, bisect offset index, patella trochlear?groove distance, patella lateral tilt angle, femoral anteversion angle, tibial external angle and knee rotational angle) calculated by CT scans slices as well as the pre?/post?operative knee functional scores including International Knee Documentation Committee (IKDC) score, Kujala score, and Lysholm score were compared be?tween the positive group and negative group at final follow up. Results The average follow?up duration was 26.3±6.7 months (range 24-31) and all the patients did not suffer from the RPD during the follow?up. Ten (26%, 10/39) patients performed positive J sign, and the remaining 29 (74%, 29/39) performed negatively. The two groups were compatible with no significant difference in age, gender, injury side, follow?up duration and preoperative knee function scores (P＞0.05). At the final follow up, the patellar laxity index in the positive J sign group was 34.9%±6.9%, while that in the negative group was 24.6%±8.6%. There was signifi?cantly difference in the patellar laxity index between two groups (t=-3.413, P=0.002). The bisect offset index in the positive group was 102.9%±12.4%, while that in the negative group was 76.0%±18.4%. There was significantly difference in the bisect offset in?dex between two groups (t=-4.268, P=0.000). The patella trochlear?groove distance in the positive group was 2.2±3.7 mm, while that in the negative group was-7.6±5.8 mm. There was significantly difference in the patella trochlear?groove distance between two groups (t=-4.233, P=0.000). The two groups were compatible with no significant difference in tibial tuberosity?trochlear groove distance, patella lateral tilt angle, femoral anteversion angle, tibial external angle and knee rotational angle (P＞0.05). The IKDC, Kujala, and Lysholm in the positive group were 86.4±6.5, 85.3±1.1, 91.5±7.9 respectively with significantly differences compared with preoperative scores 53.3±2.4, 73.2±9.7, 76.7±6.6 (t=-10.163, P=0.000; t=-1.274, P=0.023; t=-8.533, P=0.018). The IKDC, Kujala, and Lysholm in the negative group were 87.3±8.6, 84.3±4.7, 93.1±4.3 respectively with significantly differences compared with preoperative scores 49.1±4.6, 71.4±6.5, 79.5±7.0 (t=-14.381, P=0.000; t=-0.068, P=0.037; t=-6.902, P=0.013). There were no significant difference in the postoperative knee function scores between the two groups (P＞0.05). Conclusion RPD patients can recover the patellar instability from the surgical technique of MPFL reconstruction and TTO and none of them suffer from the RPD during the follow?up. However, the morbidity of post?operative positive residual patellar J sign was 26%. The positive J sign might increase the laxity of patella.

Objective: To investigate the association between high-grade pivot-shift and complete lateral meniscus posterior root (LMPR) tear in patients with anterior cruciate ligament (ACL) ruptures. Methods: From January 2013 to December 2017, a total of 86 ACL injured patients with LMPR tears were reviewed retrospectively. There were 66 males and 20 females with an average age of 27.8±8.3 years (range 16-49 years) and an mean BMI of 25.1±3.2 kg/m² (range 17.4-33.9 kg/m²). The average duration from injury to surgery was 33.5±79.4 weeks (range 3 days to 11 years). All patients were classified into high-grade pivot-shift group (60 patients of IKDC grade II-III) and low-grade pivot-shift group (26 patients of IKDC grade 0-I) according to the results of pivot-shift tests under anesthesia before ACL reconstructions. Predictive factors of high-grade pivot-shift were analyzed by multivariable Logistic regression, involving degree of LMPR tear, integrity of meniscofemoral ligament, width of lateral meniscal extrusion, KT-1000 arthrometer side-to-side difference, age, sex, and BMI. Results: The prevalence of complete LMPR tear in high-grade pivot-shift group was higher than that in low-grade pivot-shift group. High-grade pivot-shift was associated to complete LMPR tear [OR=4.096, 95% CI(1.339, 12.371), P=0.013] and KT-1000 arthrometer side-to-side difference [OR=9.632, 95% CI (3.095, 29.975), P<0.001]. The association between high-grade pivot-shift and complete LMPR tear was more striking in patients with duration from injury to surgery ≥12 weeks [OR=8.343, 95%CI(1.224, 56.853), P=0.030]. High-grade pivot-shift did not associated with meniscofemoral ligament, lateral meniscal extrusion, age, sex and BMI (P>0.05). Conclusion In patients with ACL ruptures, complete LMPR tear was an independent risk factor of high-grade pivot-shift, especially for patients with 12 weeks at least duration from injury to surgery.

Objective To investigate the incidence of concomitant anterolateral ligament (ALL) abnormality by magnetic resonance imaging (MRI) on patients with high-grade pivot-shift after anterior cruciate ligament (ACL) injuries.Methods From January 2016 to June 2016,one hundred and sixty-four consecutive patients with acute ACL injury were retrospectively reviewed.All patients underwent comprehensive pre-operative physical examinations and MRI scans.Sixty-eight patients with acute ACL injury who showed high-grade (grade Ⅱ and Ⅲ) pivot-shift phenomenon were enrolled in the high-grade pivot-shift group.They were matched in a 1:1 fashion to another 68 ACL-injured participants who showed low-grade (grade 0 and Ⅰ) pivot-shift phenomenon during the same study period.The grade of ALL injury was divided into grade Ⅰ (sprain),grade Ⅱ (partial tear) and grade Ⅲ (complete tear),and they were further compared between the high-grade pivot-shift group and the low-grade pivot-shift group on the coronal view of their T2WI MRI scans.Results The mean age of the patients in all groups was 29.3 years old.There were 43 male and 25 female patients in each group.There were no significant differences in terms of the time from injury to surgery,the body mass index and the KT-1000 side-to-side difference.Overall,there were 105 patients (77.2％,105/136) showed abnormal signal of the anterolateral ligament on MRI scans.The incidence of concomitant ALL injury in the high-grade pivot-shift group (94.1％,64/68) was significantly higher than that in the low-grade pivot-shift group (60.3％,41/68,x2=10.786,P=0.013).Specifically,there were 15,19 and 30 patients who showed grade Ⅰ,Ⅱ and Ⅲ ALL abnormality in high-grade pivot-shift group.However,there were only 29,8 and 4 patients who showed grade Ⅰ,Ⅱ and Ⅲ ALL abnormality in low-grade pivot-shift group.The incidence of patients who showed grade Ⅱ/Ⅲ MRI evidence of concomitant ALL injury was 76.6％ (49/64) in the high-grade pivot-shift group,which was also significantly higher than that in the low-grade pivot-shift group (29.3％,12/41,x2=18.452,P=0.009).Conclusion In the present study,77.2％ of the patients who showed high-grade pivot-shift demonstrated combined ALL injury on the MRI scan.In addition,patients in the high-grade pivot-shift group showed significantly higher incidence of combined ALL MRI abnormality compared with those in the low-grade pivot-shift group.The high-grade pivot-shift phenomenon might be caused by combined ACL and ALL injury.

Objective To evaluate the effectiveness of anterior cruciate ligament (ACL) reconstruction combined with anterolateral ligament(ALL)reconstruction in ACL injury patients with high-grade pivot shift.Methods From May 2015 to April 2016,156 patients underwent ACL reconstruction by the same surgeon,and 22 of them with grade 2/3 pivot shift were included in this study.Anteroposterior knee stability was evaluated using KT1000 measurement,and the rotatory stability was assessed using the pivot-shift test.The Lysholm score was used to monitor the clinical function.Results There were 14 male subjects and 8 females,with an average age of 29.3 years.The mean follow-up period was 8.6 months.The mean side-to-side difference of anteroposterior knee laxity was 2.1 ± 0.6 mm,significantly improved compared with the preoperative 8.9 ± 3.1 mm.The preoperative pivot-shift indicated 2+ in 20 patients and 3+ in 2 patients,while at the final follow-up,21 patients had negative pivot shift with 1 of 1+ pivot shift.The difference was significant.The average Lysholm score improved significantly from 60.5 ± 12.3 preoperatively to 79.2 ± 7.8 at the final follow-up.Conclusion The rotatory instability can be effectively restored through the ACL reconstruction combined with ALL reconstruction in patients with high-grade pivot shift.The early-stage knee stability and functional outcomes indicate significant improvement postoperatively.