Objective:To compare the clinical effect of anchor fixation of medial collateral ligament（MCL）and non-repaired treatment combined with arthroscopic anterior and posterior cruciate ligament reconstruction in the treatment of type KD-IIIM（Schenck classification）dislocation of knee joint.Methods:A retrospective case-control study was conducted to analyze the clinical data of 41 patients with type KD-IIIM dislocation of the knee joint admitted to Xi'an Honghui Hospital of Xi'an Jiaotong University from September 2015 to September 2017. There were 26 males and 15 females，with the age range of 15-62 years［（37.7±13.9）years］. A total of 21 patients were treated by arthroscopic anterior and posterior cruciate ligament reconstruction and anchor fixation of MCL（repaired group）and 20 patients by arthroscopic anterior and posterior cruciate ligament reconstruction without MCL repair（non-repaired group）. The perioperative complications were observed. Comparisons between the two groups were made before operation，4 months after operation and at the last follow-up in terms of Lysholm score，International Knee Documentation Committee（IKDC）score，Visual Analogue Scale（VAS）and range of motion of joint flextion and extension. The medial opening distance of stress X-ray of lower limbs was also observed at the last follow-up.Results:All patients were followed up for 48-66 months［（54.4±5.1）months］. No perioperative complications were noted. The Lysholm score，IKDC score，VAS and range of motion of joint flextion and extension showed no statistical differences between the two groups before operation（ P>0.05），and all were improved from the preoperative level at 4 months after operation and at the last follow-up（ P<0.05）. The Lysholm score in repaired group were（69.7±5.1）points and（83.8±4.9）points at 4 months after operation and at the last follow-up，significantly higher than those in non-repaired group［（61.0±5.5）points and（74.6±6.0）points］（ P<0.05）. The IKDC score in repaired group was（71.8±4.0）points at 4 months after operation，significantly higher than that in non-repaired group［（71.1±3.9）points］（ P<0.05）. The IKDC score in repaired group was（82.3±5.1）points at the last follow-up，similar with that in non-repaired group［（83.2±4.0）points］（ P>0.05）. The VAS in repaired group was（2.5±0.6）points at 4 months after operation，significantly decreased in comparison with（3.2±1.2）points in non-repaired group（ P<0.05）. The VAS in repaired group was（2.0±1.4）points when compared to（2.2±1.3）points in non-repaired group at the last follow-up（ P>0.05）. The range of motion of joint flextion and extension in repaired group was（107.6±6.9）° and（125.9±7.8）° at 4 months after operation and at the last follow-up，significantly increased in comparison with（89.6±4.0）° and（120.9±5.2）° in non-repaired group（ P<0.05）. The medial opening distance in repaired group was（2.3±0.2）mm at the last follow-up，significantly decreased when compared to（3.1±0.2）mm in non-repaired group（ P<0.05）. Conclusion:For type KD-IIIM knee dislocation，arthroscopic anchor fixation of MCL or without MCL repair combined with anterior and posterior cruciate ligament reconstruction are both effective in satisfactory functional recovery，but MCL repair contributes to earlier function recovery，faster pain relief and more reliable joint stability.

Objective:To investigate the initial effectiveness of manual techniques versus navigation positioning system-assisted reconstruction for anterior cruciate ligament (ACL) injuries in children and adolescent populations.Methods:A retrospective analysis was conducted on 28 patients with ACL rupture who underwent primary total epiphyseal ACL reconstruction in the Sports Medicine Treatment Center of Honghui Hospital Affiliated to Xi'an Jiaotong University from January 2019 to October 2022. Patients were categorized into two groups based on the method of guide needle insertion: the manual group (guide needle insertion relying on the operator's expertise) and the robot-assisted group (guide needle insertion assisted by the Tianji robot navigation and positioning system). The manual group comprised 14 cases (9 males, 5 females) with an average age of 13.59±1.59 years, while the robot-assisted group included 14 patients (10 males, 4 females) with an average age of 13.27±1.66 years. The operation time, intraoperative fluoroscopy times, guide needle placement times, the distance between the central point of the internal articular opening of the tibial and femoral bone tunnel and the ideal point, the rate of epiphyseal inflammation, and the International Knee Documentation Committee (IKDC) subjective score, Lysholm score, KT-2000 ligament relaxation, lower limb force line were compared between the two groups.Results:The follow-up duration was 19.9±6.3 months for the manual group and 18.8±4.9 months for the robot group ( t=0.546, P=0.589). The manual group's operation duration was 123.0±12.6 min, significantly longer than the robot group's 96.4±12.9 min ( t=5.502, P<0.001). Intraoperative fluoroscopy was performed 11.8±3.1 times in the manual group, markedly more than the robot group's 3.7±0.8 times ( t=9.434, P<0.001). The robot group required only one guide needle placement for both femur and tibia, while the manual group had 5.7±1.2 placements on the femur side and 4.6±1.8 on the tibia side. The distance between the femoral joint's central point and the ideal point was 0.87±0.20 mm in the robot group, superior to the manual group's 1.92±0.64 mm ( t=5.816, P<0.001). Similarly, the distance between the central point and the ideal point was 1.15±0.34 mm for the robot group, better than the manual group's 1.94±0.55 mm ( t=4.582, P<0.001). No cases of epiphyseal irritation were observed in the robot group, while 21% (3/14) of the manual group experienced tibial or femoral epiphyseal plate involvement. At 3 months post-surgery, the robot group exhibited higher IKDC subjective scores (90.57±8.46) and Lysholm scores (86.29±5.09) compared to the manual group (83.50±6.19 and 80.93±5.93), respectively ( P<0.05). However, at the final follow-up, there were no significant differences in IKDC subjective scores, Lysholm scores, or KT-2000 ligament relaxation between the two groups ( P>0.05). Both groups showed normal lower limb force alignment and no abnormal growth or development. Conclusion:Tianji robot navigation and positioning system-assisted ACL reconstruction in children and adolescents offer advantages such as precise positioning, shorter operation times, reduced intraoperative fluoroscopy, faster recovery, and enhanced epiphyseal protection compared to manual methods.

Objective:To compare the clinical efficacy of robot-assisted and simple arthroscopic reconstruction of anterior cruciate ligament (ACL).Methods:A retrospective cohort study was conducted to analyze the clinical data of 37 patients with ACL tear admitted to Honghui Hospital of Xi′an Jiaotong University from January 2020 to September 2020. There were 24 males and 13 females, aged 16-45 years［(30.7±9.8)years］. A total of 17 patients were treated by robot-assisted ACL reconstruction (robot-assisted group), and 20 patients by simple arthroscopic ACL reconstruction (simple arthroscopy group). The operation time, number of guide wire drilling, positional accuracy of bone tunnel (distance between the central point of bone tunnel and ideal anatomical point) and perioperative complications were compared between the two groups. Knee stability was evaluated by Lachman test and KT-2000 measurement, and knee function by Lysholm score, International Knee Documentation Committee (IKDC) score and range of motion of joint flexion and extension before operation, at 4 months after operation and at the last follow-up.Results:All patients were followed up for 12-18 months［(13.1±4.1)months］. The operation time in robot-assisted group was (83.8±11.3)minutes, significantly longer than (50.4±9.1)minutes in simple arthroscopy group ( P<0.01). The number of guide wire drilling in robot-assisted group was (2.2±0.5)times, less than (2.5±0.4)times in simple arthroscopy group ( P<0.05). The distance between the central point of bone tunnel and ideal anatomical point was (1.3±0.3)mm in robot-assisted group, not significantly different from (1.4±0.3)mm in simple arthroscopy group ( P>0.05). There were no perioperative complications in both groups. The two groups showed no significant differences in Lachman test, KT-2000 measurement, Lysholm score, IKDC score and range of motion of joint flexion and extension before operation, at 4 months after operation and at the last follow-up (all P>0.05). The above indices in both groups were significantly improved at 4 months after operation and at the last follow-up as compared with those before operation (all P<0.01), and both groups showed no significant difference in the above indexes at 4 months after operation and at the last follow-up as compared with those before operation (all P>0.05). Conclusion:Compared with simple arthroscopic ACL reconstruction, robot-assisted ACL reconstruction can prepare a bone tunnel once with good location and direction in one time and achieve similar results in stability and functional recovery of the joint except for slightly longer operation time.