Comparison of ultrasound-guided femoral + anterior sciatic nerve block and genicular nerve block for postoperative pain in total knee arthroplasty

Abstract

Purpose: This study aimed to compare the effectiveness of ultrasound-guided femoral and anterior sciatic (FAS) nerve blocks and genicular (G) nerve blocks as preventive analgesia methods after total knee arthroplasty.
 Materials and Methods: Fifty patients, aged 55–80 years were divided into two groups preoperatively. Patients in the FAS group (n=25) received 20 mL solutions (10 mL 0.5% bupivacaine, 1 mL [4 mg] dexamethasone, and 9 mL saline) in both femoral and sciatic blocks. Patients in the G group (n=25) received 5 mL solutions (2 mL 0.5% bupivacaine, 1 mL [4 mg] dexamethasone, and 2 mL saline) for each nerve. Patients were assessed 24 h postoperatively, and pain scores, time to first analgesic requirement, total analgesic dose, and postoperative complications during the first 24 h were recorded.
 Results: VAS scores at postoperative 0, 1, and 6 h and the total amount of tramadol consumed 24 h were lower in the FAS group than in the G group. There was no requirement for additional analgesia in the first 24 h in the FAS group; however, 9 patients required additional analgesia in the G group. 
 Conclusion: USG FAS nerve blocks were superior to the genicular nerve blocks in TKA. Additionally, the genicular block doesn’t cause motor block. A genicular block can be considered as an alternative with this regard.