Abstract
Objectives
The goal of this retrospective study was to compare two different processes of pain control after total knee arthroplasty (TKA): local anesthesia versus femoral nerve block. The tested hypothesis was that the patient's ability to be discharged was obtained sooner with the local anesthesia process.
Methods
110 patients consecutively operated on for TKA by a single surgeon without any selection criterion were included. The study group included 58 patients operated on under general anesthesia with infiltration of the surgical field with local anesthesia. The control group included 52 patients operated on under general anesthesia and continuous femoral nerve block. In the study group, 200 ml of ropivacaïne 5% were injected into the surgical field, and an intra-articular catheter was left to allow continuous infusion of ropivacaïne (20 ml/h during 24 hours). The control group was treated by a femoral nerve block with ropivacaïne during 24 hours. Discharge was considered allowed when the patient was able to walk independently, go upstairs and downstairs independently, when the knee flexed over 90° and if the subjective pain assessment (VAS) was under 3/10.
Results
Discharge allowance was obtained sooner (mean 2 days) in the study group (p<0.01). 40 patients of the study group (69%) and 2 patients of the control group (4%) were able to stand up on the day of implantation (p<0.001). Deambulation was possible at D1 in the study group and D2 in the control group (p<0.001). Gait was possible at D4 in the study group and D6 in the control group (p<0.05). Discharge was possible 2 days earlier in the study group (p<0.01). Active quadriceps function was recovered 2 days earlier in the study group (p<0.001). Knee flexion exceeded 90° 2 days earlier in the study group (p<0.001). There was a faster decrease of the pain VAS in the study group, but the total consumption of analgesic was not different in the two groups. The complication rate was not different in the two groups.
Conclusion
The process using local anesthesia may allow a better pain control after TKA, and consequently a faster rehabilitation and an earlier discharge.
