Comparison of Local Infiltration Analgesia With Femoral Nerve Block for Total Knee Arthroplasty: A Prospective, Randomized Clinical Trial

Total knee arthroplasty (TKA) is usually associated with severe postoperative pain, which can prevent rehabilitation of patients’ knee function and influence the satisfaction of surgery. Local infiltration analgesia (LIA) as a new method to managing postoperative pain has been applied in clinical practice recently. However, the safety and efficacy of LIA compared with femoral nerve block (FNB) in postoperative pain management of TKA still remains controversial. Thus, we conducted an original clinical trial to compare LIA and FNB.

One hundred fifty-seven patients undergoing TKA were enrolled in a randomized, double-blind, single-center study. The patients received either FNB (group A) or periarticular infiltration of local anesthetic (group B). The morphine consumption used in patient-controlled analgesia after surgery, postoperative Visual Analogue Scale (VAS), Knee Society Score, and range of motion before and after surgery in both groups were analyzed, as well as the adverse effects.

Group A consisted 78 patients, and group B contained 79 patients. The patients’ characteristics including age and body mass index had no significant difference (P > .05). Morphine consumption, VAS at rest, range of motion, and Knee Society Score were similar between the 2 groups. Our study showed group B, the local anesthetic group had less VAS with movement on postoperative day 1 (P = .01) than that of group A, which means a better pain control. Because of the study design, the surgery time showed no significant difference. Eighteen patients in group A and 21 patients in group B experienced mild-to-medium nausea or vomiting. One patient in group B had dizziness and one patient in group A suffered a neuropraxic injury to the femoral nerve. No urinary retention case was seen during inpatient days. There were no significant differences between the 2 groups about side effects.

Our research showed that no significant differences were observed between the 2 treatment groups. LIA could provide a similar analgesic effect to FNBs with a low incidence of complications.