Analgesic Effect Of Different Concentrations Of Ropivacaine Adductor Canal Block Combined With Lateral Femoral Cutaneous Nerve Block After Total Knee Arthroplasty

Objective:Comparison of the analgesic effect of ultrasound-guided ropivacaine adductor canal block combined with lateral femoral cutaneous nerve block after total knee arthroplasty and the effect on knee function.Methods:Ninety patients who received primary unilateral TKA in subarachnoid block were randomly divided into three groups: 0.2% ropivacaine(group A),0.25% ropivacaine(group B),and 0.3% ropivacaine(group C).The three groups received ACB+LFCNB before surgery,and the postoperative VAS pain score,the consumption of Sufentanil 24 hours after surgery,the first rescue analgesic time,postoperative knee range of motion(ROM),quadriceps muscle strength and postoperative complications were recorded.Results:Compared with group A,the resting VAS scores and exercise VAS scores in groups B and C at 4,8,12 and 24 h after surgery were decreased(P <0.05),the consumption of sufentanil within 24 hours after surgery was decreased(P <0.05),the time of first rescue and analgesia was prolonged(P<0.05),and the motion of the knee on the day after surgery was increased(P<0.05).The above results showed no significant difference between group B and group C.There were no significant differences in knee range of motion,quadriceps strength and incidence of complications 1 and 2 days after surgery among the three groups.Conclusion:In the use of ACB+LFCNB for postoperative analgesia of TKA,0.25% and 0.3%ropivacaine,compared with 0.2% ropivacaine,can improve the early postoperative pain and facilitate the functional recovery of the knee joint after surgery.Meanwhile,0.25%ropivacaine can provide the same analgesic effect as 0.3% Ropivacaine.Based on this study,researchers can further explore the optimal concentration of ACB+LFCNB.