[Modified application of interface screw in femoral side during anterior cruciate ligament reconstruction]

To compare clinical effects of the improved interface screw fixation of femoral end of anterior cruciate ligament with classic femoral lateral loop plate fixation.

A retrospective analysis of 65 patients who underwent arthroscopic anterior cruciate ligament reconstruction from January 2019 to September 2021 were performed. According to the different fixation methods of the femoral side, 35 patients were divided into loop plate fixation(loop plate group), including 27 males and 8 females, aged from 18 to 50 years old with an average of (35.00±7.60) years old;30 patients in interface screw fixation(interface screw group), including 20 males and 10 females, aged from 18 to 50 years old with an average of (32.00±8.50) years old. Hospital stay, hospital expenses, operation time, complications, C-reactive protein at 1, 3, 6 days after operation, and postoperative Lysholm score and International Knee Documentation Committee(IKDC) score at 18 months were compared between two groups.

All patients were successfully operated, and obtained follow-up from 18 to 36 months with an average of (25.16±4.50) months. Anterior drawer test and Lachman test of all patients turned to negative. There were no statistical differences in hospital stay, hospital expenses and complications between two groups(P>0.05);operation time in loop plate group was (74.00±6.84) min, and (91.67±6.34) min in interface screw group, and had difference between two groups(P<0.05). C-reactive protein on the 1st and 3rd day after operation was (40.00±10.10), (20.00±8.23) mg·L^-1 in loop plate group, and (60.00±8.93), (30.00±8.66) mg·L^-1 in interface nail group, had statistical difference between two groups (P<0.05);while there was no difference in C-reactive protein on the 6th day after operation(P>0.05). At 18 months after operation, Lysholm and IKDC scores showed no significant difference between two groups (P>0.05). In loop plate group, medullary enlargement on coronal and sagittal views were (2.75±0.19) mm, (1.55±0.25) mm, and (2.81±0.22) mm, (1.61±0.20) mm in interface screw group, and had statistical difference between two groups(P<0.05).

In the reconstruction of anterior cruciate ligament, the common interface screw on the femoral side is changed to the sheath interface screw, and intramedullary screw is changed to the compression and fixation of tendon from outside to inside of joint. Although the operation procedure is relatively complicated and operation time is slightly longer, it has advantages of no residual metal foreign body after operation, and clinical effect is no different from classical loop plate suspension fixation, which is still a good choice.