Adductor Canal BlockversusFemoral Nerve Block for Total Knee Arthroplasty

Abstract

Background: This prospective double-blinded, randomized controlled trial compared adductor canal block (ACB) with femoral nerve block (FNB) in patients undergoing total knee arthroplasty. The authors hypothesized that ACB, compared with FNB, would exhibit less quadriceps weakness and demonstrate noninferior pain score and opioid consumption at 6 to 8 h postanesthesia. Methods: Patients received an ACB or FNB as a component of a multimodal analgesic. Quadriceps strength, pain score, and opioid consumption were assessed on both legs preoperatively and at 6 to 8, 24, and 48 h postanesthesia administration. In a joint hypothesis test, noninferiority was first evaluated on the primary outcomes of strength, pain score, and opioid consumption at 6 to 8 h; superiority on each outcome at 6 to 8 h was then assessed only if noninferiority was established. Results: Forty-six patients received ACB; 47 patients received FNB. At 6 to 8 h postanesthesia, ACB patients had significantly higher median dynamometer readings versus FNB patients (median [interquartile range], 6.1 kgf [3.5, 10.9] (ACB) vs. 0 kgf [0.0, 3.9] (FNB); P < 0.0001), but was not inferior to FNB with regard to Numeric Rating Scale pain scores (1.0 [0.0, 3.5] ACB vs. 0.0 [0.0, 1.0] FNB; P = 0.019), or to opioid consumption (32.2 [22.4, 47.5] ACB vs. 26.6 [19.6, 49.0]; P = 0.0115). At 24 and 48 h postanesthesia, there was no significant statistical difference in dynamometer results, pain scores, or opioid use between the two groups. Conclusion: At 6 to 8 h postanesthesia, the ACB, compared with the FNB, exhibited early relative sparing of quadriceps strength and was not inferior in both providing analgesia or opioid intake.

The adductor canal block provides effective analgesia similar to a femoral nerve block in patients undergoing total knee arthroplasty—a retrospective study

“…In the current study, patients in the ACB group were significantly better participants in postoperative physical therapy vs patients who received FNB. This finding is consistent with previous studies that have demonstrated ACB preserves quadriceps strength [15,26,27] and that ACB enhances ambulation compared with FNB [19,25]. Adductor canal block preserves motor function, resulting in improved physical therapy after TKA.…”

“…Patients in the ACB group had better quadriceps strength, and pain scores were similar compared with those in the FNB group. However, in this study, patients also received postoperative epidural analgesia, which may have confounded the pain scores and opioid consumption results [27]. In the current study, patients in the ACB group were significantly better participants in postoperative physical therapy vs patients who received FNB.…”

“…Similarly, Jaeger et al [26] performed a prospective study comparing continuous ACB to continuous FNB after TKA and found that patients in the ACB group had more preserved quadriceps strength. A more recent study by Kim et al [27] analyzed postoperative quadriceps strength and pain scores in patients who received either a single-shot FNB or ACB. Patients in the ACB group had better quadriceps strength, and pain scores were similar compared with those in the FNB group.…”

Adductor Canal Block Combined with Sciatic Nerve Block Vs. Local Analgesic Infiltration for Pain Control after Total Knee Arthroplasty

“…The anterior branch of obturator nerve, the saphenous nerve, and a branch of the posterior femoral nerve within the adductor canal are sensory to the surrounding tissue of the knee joint [33,34]. Kim et al [35] femoral nerve block and adductor canal block and for post-operative pain management with TKR, they found that the comparative reduction of post-operative pain with less opioid consumption, additionally, adductor canal block had spring of the quadriceps with no difference in range of motion. Wang et al [24] performed a metaanalysis from randomized controlled trials and found that no difference between adductor canal block and femoral nerve block as regards the pain management or morphine consumption after TKR, in addition, a better knee mobility with sparing of quadriceps strength and decreased risk of falls.…”

Recent advances in regional anaesthesia

“…The primary advantage of the adductor canal block is sparing of the motor branches to the quadriceps muscles resulting in earlier patient mobility following TKA [21].…”