Postoperative pain control by intra-articular local anesthesia versus femoral nerve block following total knee arthroplasty: Impact on discharge

IntroductionThe goal of this retrospective study was to compare pain control following total knee arthroplasty (TKA) on a perioperative protocol of local anesthesia (LA) versus the more classical femoral nerve block (FNB) technique.HypothesisFitness for discharge would be achieved earlier using the LA protocol.MaterialsNinety-eight consecutive TKA patients operated on by a single surgeon were included with no selection criteria. In the study group (49 patients), 200 mL ropivacaine 5% was injected into the surgical wound and an intra-articular catheter was fitted to provide continuous infusion of 20 mL/h ropivacaine for 24 h. The control group (49 patients) received ropivacaine FNB. Discharge fitness (independent walking, knee flexion > 90°, quadricipital control, pain on VAS ≤ 3) and hospital stay were assessed.ResultsDischarge fitness was achieved significantly earlier in the study group (4.2 ± 2.6 versus 6.7 ± 3.2 days; P = 0.0003), with significantly shorter mean hospital stay (6.1 ± 3.4 versus 8.8 ± 3.5 days; P = 0.0002). The complications rate did not differ between study and control groups.DiscussionAlthough retrospective, this study indicates that the LA protocol improves management of post-TKA pain and accelerates rehabilitation, thereby, reducing hospital stay. The acceleration effect may be due to the absence of quadriceps inhibition.Level of evidenceLevel III – Case control study.