Objective To review the research progress of injection sites of local infiltration analgesia (LIA) in total knee arthroplasty (TKA). MethodsThe relevant domestic and foreign literature in recent years was extensively reviewed. The neuroanatomy of the knee, and the research progress of the selection and the difference of effectiveness between different injection sites of LIA in clinical studies were summarized. ResultsLarge concentrations of nociceptors are present throughout the various tissues of the knee joint. Patellar tendon, subpatellar fat pad, lateral collateral ligament insertions, iliotibial band insertions, suprapatellar capsule, and posterior capsule were more sensitive to pain. Most current studies support injections into the lateral capsule, collateral ligament, retinaculum, quadriceps tendon, fat pad, and subcutaneous tissue. Whether to inject into the back of the knee and subperiosteum is controversial. ConclusionThe relative difference of knee tissue sensitivity to pain has guiding significance for the selection of LIA injection site after TKA. Although researchers have conducted clinical trials on injection site and technique of LIA in TKA, there are certain limitations. The optimal scheme has not been determined yet, and further studies are needed.
ObjectiveTo evaluate the early effectiveness of local infiltration anesthesia (LIA) with compound betamethasone in total knee arthroplasty (TKA). MethodsThe clinical data of 102 patients with knee osteoarthritis who were treated by TKA and met the selection criteria between May 2022 and March 2023 were retrospectively analyzed. They were divided into control group and study group according to whether LIA preparation was added with compound betamethasone, with 51 cases in each group. There was no significant difference of baseline data, such as age, gender, body mass index, operative side, preoperative range of motion (ROM), Knee Society Score (KSS), white blood cell (WBC), and hematocrit between the two groups (P>0.05). The intraoperative total blood loss and hidden blood loss were recorded, and WBC was recorded on the 1st, 2nd, and 3rd days after operation. Pain was assessed by visual analogue scale (VAS) score on the 1st, 2nd, and 3rd days after operation and morphine intake milligrames equivalent within 48 hours after operation. Passive ROM, maximum extension and flexion angles of knee joint were measured on the 3rd day after operation; the early postoperative complications were recorded. ResultsThere was no significant difference in total blood loss and hidden blood loss between the two groups (P>0.05). The postoperative pain levels in both groups were relatively mild, and there was no significant difference in VAS scores in the first 3 days after operation and in morphine intake milligrams equivalent within 48 hours after operation between the two groups (P>0.05). The WBC in the first 3 days after operation was significantly improved in both groups (P<0.05). The WBC in the study group was significantly higher than that in the control group on the 1st and 2nd days after operation (P<0.05), but there was no significant difference between the two groups on the 3rd day after operation (P>0.05). On the 3rd day after operation, the maximum extension angle of knee joint in the study group was smaller than that in the control group, while the maximum flexion angle and passive ROM of knee joint in the study group were larger than those in the control group, and the differences were significant (P<0.05). There were 6 cases of fever and 17 cases of deep venous thrombosis in the control group, and 1 case and 14 cases in the study group, respectively. There was no poor wound healing and periprosthetic joint infection in the two groups, and there was no significant difference in the incidence of complications between the two groups (P>0.05). ConclusionThe application of compound betamethasone in LIA during TKA is a safe and optimal strategy to promote the early postoperative rehabilitation of patients.