Comparison of Adductor Canal Block versus Femoral Nerve Block for Ambulatory Distance on Postoperative Day-1 Following Unilateral TKR Surgery- An RCT Study

Background: Total knee replacement (TKR) is associated with intense post-operative pain. Providing both optimal analgesia and early mobilization are vital for the patient. We hypothesized the adductor-canal-block, being a pure sensory block, provides a longer ambulation distance by patient when compared with femoral nerve block as the latter causes both sensory and motor block.Method: Patients aged 30-80 years scheduled for TKR were included in this randomized controlled trial. The patients were divided into two groups, one received a continuous adductor-canal-block(n=25)and other group received continuous femoral nerve block(n=25) via a catheter with continuous infusion of 0.2% Ropivacaine at the rate of 5-10 ml/hour. During the next 24 hours VAS and MMT score were calculated at different intervals. 10 metre ambulation distance covered by patients was measured after 24hr of surgery.Result: 50 patients were analysed using student t test. The Visual Analogue Scale and Manual Muscle Testing score were noted during 24-hour period post-op. There was a significant difference among the VAS scores in the two groups at 2 hours post-op period only. The MMT was significantly different at 2 instances – 6 and 12-hours post-op. The ambulation distance post-24-hours surgery showed no significant difference between the two groups.Conclusion: Based on our study it can be concluded that either ACB or FNB can be administered to the patients as both blocks are almost equally effective in terms of ambulation distance after 24 hrs of surgery and pain relief in post-operative period.Keywords: Total knee replacement, Adductor canal block, Femoral nerve block, Ambulation distance, VAS and MMT.