Comparison of analgesic efficacy between continuous adductor canal nerve block catheter with and without posterior capsular infiltration in patients undergoing unilateral robotic total knee replacement: A retrospective study

Total knee arthroplasty is a major surgical procedure that can result in significant pain during recovery. Adequate analgesia is, therefore, the cornerstone in enabling good functional outcomes for the patient. Our study assessed retrospectively, the post-operative pain scores with continuous proximal adductor canal nerve block catheter with and without posterior capsular infiltration. Materials and Methods: All patients undergoing unilateral robotic total knee arthroplasty were randomized into two groups. One group received only a continuous adductor canal nerve block catheter. The other group was provided with a continuous adductor canal nerve block catheter with posterior capsular infiltration. The post-operative VAS (Visual Analogue Scale) score and the time of the first rescue analgesic were noted. Results: The group which received continuous adductor canal nerve block catheter with posterior capsular infiltration had better post-operative analgesia with delayed time of first rescue analgesia. Hence local anaesthetic infiltration in the posterior capsule provided superior recovery rates in terms of pain management. Conclusion: Our study concluded that patients receiving continuous adductor canal catheters and posterior capsular infiltration had better post-operative analgesia than those receiving only continuous adductor canal catheters. This aided in faster recovery and mobilization in robotic knee arthroplasty, contributing to fast-tracking.