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

AbstractIntroductionThe 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), 200mL ropivacaine 5% was injected into the surgical wound and an intra-articular catheter was fitted to provide continuous infusion of 20mL/h ropivacaine for 24h. 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±3.2days; P=0.0003), with significantly shorter mean hospital stay (6.1±3.4 versus 8.8±3.5days; 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