Success rate and efficacy of intentional ipsilateral epidural catheter placement for anterior cruciate ligament reconstruction surgery: a retrospective analysis of 307 consecutive patients

PURPOSE: Intentional placement of an epidural catheter toward the operative side can produce a predominantly ipsilateral effect, which may benefit patients undergoing unilateral knee surgery. In this study, we retrospectively evaluated the success rate and efficacy of intentional ipsilateral epidural catheter placement in patients undergoing anterior cruciate ligament reconstruction (ACLR). METHODS: With IRB approval, we retrospectively analyzed existing clinical data that had been routinely collected from patients who underwent ACLR and received intentional ipsilateral epidural catheter placement combined with spinal anesthesia between January 2021 and December 2023. All epidural catheters were advanced toward the operative side and used for continuous infusion for 3 days. Catheter tip position was evaluated by X-ray on postoperative day (POD) 1. Pain scores on the Numerical Rating Scale (NRS), analgesic requirements, distribution of sensory blockade, motor function, and complications through POD4 were evaluated. RESULTS: Of 307 patients undergoing ACLR, 297 patients were included in the analysis. Catheters were inserted between the T11/12 and L1/2 intervertebral spaces. X-rays revealed that the epidural catheter tip was located on the operated side in 274 patients (92.3%). An ipsilateral-dominant sensory block covering lumbar segments was observed in more than 90% of patients throughout 3 PODs. Median NRS scores during mobilization remained below 3 with epidural infusion, and 263 patients (88.6%) could perform active straight leg raise on the operative side on POD1. CONCLUSION: Intentional ipsilateral epidural catheter placement demonstrated a high success rate, provided motor-sparing and satisfactory analgesia in patients undergoing ACLR.