Objective To investigate individual variations of the femoral isometric poiIit of anterrior cruciate ligament(ACL). Methods The femoral isometric points(i)were determined by measuring the knee joint lateral projections in 100 adults.The distances from the femoral isometric point i to the posterior border of intercondylar notch were measured and compared among 4 age groups(20 to 30 y,30 to 40 y,40 to 50 y and>50 y)by 2 × 2 factor analysis and Student-Newman-Keuls (SNK-q)Analysis to determine the effects of age and gender on the measurements. Results The average distance was(10.6±1.55)mm,ranging from 15.05 am to 7.50 mm.The 2×2 factor analysis showed the differences were signifcant between age groups(F=2.843,P=0.042)and between sexes(F=4.245,P=0.042).but the age and sex factors were not interacted (F=0.456,P=0.7 14). The SNK-q Analysis revealed the differences were significant between the 20 to 30 y group and the 40 to 50 y group as well as the>50 y group(P<0.05),but not significant between the 30 to 40 y group and the 20 to 30 y group(P>0.05).No signifieant difference was observed between any two of the 30 to 40 y group,40 to 50 y group and>50 y group(P>0.05). Conclusion Since the ACL femoral isometric points vary from person to person,it is valuable to check them twice radiologically before and during the operation.

Objective To evaluate the risk of chondral injury during anterior cruciate ligament (ACL) reconstruction using a double cross-pin femoral fixation device via the anteromedial portal in Chinese cadavers. Methods Nine specimens of the knee (6 left ones and 3 right ones) were taken from 5 male and 4 female conservative cadavers of Chinese adult. The average age of the cadavers were 34.8 (26 to 45)years old. Femoral tunnel drilling and cross-pin guide insertion were performed using the Rigidfix Cross Pin device through the anteromedial portal. The ACL reconstructions were simulated at 3 entrance points of the cross-pin (0°, 45° and 90° relative to the horizontal plane) . The risks of chondral injury were statistically analyzed when the cross-pin entrance point was at the 3 different positions relative to the femoral chondral surface. Results The incidence of chondral injury was 100% when the Rigidfix cross-pin guide was at 90° relative to the horizontal plane. When the Rigidfix cross-pin guide was at 45° and 0° the incidences of chondral injury were 66. 7% and 22. 2% respectively. Conclusion Since there is always a risk of chondral injury when the Rigidfix cross-pin device is used to reconstruct ACL via the anteromedial portal, the anteromedial portal is not recommended for the ACL reconstruction using Rigidfix femoral fixation.

[Objective]To investigate the feasibility and short-term effects of arthroscopic suture fixation with cannulated screw and washer for bony avulsion of the posterior cruciate ligament.[Method]Arthroscopic suture fixation with cannulated screw and washer was carried out in 30 patients with bony avulsion of the posterior cruciate ligament.The posterior cruciate ligament and avulsion bone fragment were held together with two Ethibond 5 polyester threads,which were first wrapped around the posterior cruciate ligament from the anterior to the posterior,and then tied behind the posterior cruciate ligament and over the bone fragment.The threads were pulled out through tibia tunnels,tighted and fixed on cannulated screw and washer under the tibia tunnels 2 cm.[Result]The operation time were 60-90 min.A follow-up was made in 10 patients for 6-12 months.All fractures were united without displacement at 6 weeks after operation.No postoperative complications occurred.The Lysholm scores were 83-95(89.6?4.03).[Conclusion]Arthroscopic suture fixation with cannulated screw and washer for bony avulsion of the posterior cruciate ligament technique is simple to perform and gives a satisfactory short-term results.

Objective:To investigate the effects of ligamen remnant preservation on knee joint function and proprioception recovery in patients with anterior cruciate ligament (ACL) injuries during ACL reconstruction under arthroscope.Methods:The clinical data of 266 patients with ACL injuries,who were treated in the 174th hospital of PLA from January 2010 to March 2016,were retrospectively analyzed.All the patients underwent ACL reconstruction under arthroscopy,among them,163 patients with remnant preservation were chosen as remnant preservation group;103 patients with completely clearing remnant preservation in the operation,as non remnant preservation group.All the patients were followed up for more than 12 months,and the knee function and proprioception recovery of the two groups were evaluated.Results:There were no significant differences in the knee ipsilateral Lysholm score,international knee documentation committee knee assessment scale (IKDC) score,passive activity detection threshold,passive angle regeneration test results between the two groups before operation,9 and 12 months after operation (P＞0.05).The Lysholm scores and IKDC scores of the two groups at each time point were significantly higher than those before operation,the passive activity detection threshold and passive angle regeneration test results were significantly lower than those before operation (P＜0.05).The Lysholm scores and IKDC scores in the remnant preservation group 3 and 6 months after operation were higher than those in the non remnant preservation group,the passive activity detection threshold and the passive angle regenerated test results were lower than the non remnant preservation group,the difference was statistically significant (P＜0.05).Conclusion:Remnant preservation in the ACL reconstruction under arthroscopy can accelerate the recovery of knee joint function and proprioception,and satisfactory clinical results are achieved,which is worth popularizing.

Objective To compare the efficacy of single-tunnel single-bundle and double-bundle reconstruction in patients with anterior cruciate ligament reconstruction.Methods A total of 64 patients with anterior cruciate ligament rupture in our hospital were randomly divided into single-bundle group with 32 cases and double-bundle group with 32 cases, given single-tunnel single-bundle anterior cruciate ligament reconstruction, and single-tunnel double-bundle anterior cruciate ligament reconstructions.The IKDC, Tegner, Lysholm and KT-2000 scores were compared in two groups preoperation and at 12 months after operation.Results Thee were no significant difference in sex, age, injured site and injured time in the two groups(P>0.05).The IKDC, Tegner and Lysholm scores after operation were higher than operation before, and the KT-2000 scores was lower than operation before in two groups, and the differences were statistically significant(P<0.05).But there were no significant differences in IKDC, Tegner, Lysholm and KT-2000 scores between two groups before and after treatment(P>0.05).Conclusion The subjective and objective function scores of two groups showed no significant difference.But single-tunnel double-bundle for anterior cruciate ligament reconstruction is characterized by simplicity, firmly fixation and effectively restoration of knee stability.

Objective To compare the efficacy of single-tunnel single-bundle and double-bundle reconstruction in patients with anterior cruciate ligament reconstruction.Methods A total of 64 patients with anterior cruciate ligament rupture in our hospital were randomly divided into single-bundle group with 32 cases and double-bundle group with 32 cases, given single-tunnel single-bundle anterior cruciate ligament reconstruction, and single-tunnel double-bundle anterior cruciate ligament reconstructions.The IKDC, Tegner, Lysholm and KT-2000 scores were compared in two groups preoperation and at 12 months after operation.Results Thee were no significant difference in sex, age, injured site and injured time in the two groups(P>0.05).The IKDC, Tegner and Lysholm scores after operation were higher than operation before, and the KT-2000 scores was lower than operation before in two groups, and the differences were statistically significant(P<0.05).But there were no significant differences in IKDC, Tegner, Lysholm and KT-2000 scores between two groups before and after treatment(P>0.05).Conclusion The subjective and objective function scores of two groups showed no significant difference.But single-tunnel double-bundle for anterior cruciate ligament reconstruction is characterized by simplicity, firmly fixation and effectively restoration of knee stability.