Comparative Study between Adductor Canal Block and Femoral Nerve Block for Postoperative Analgesia in Knee Arthroscopy

Abstract
Background: Femoral Nerve Block (FNB) is one of the easiest peripheral nerve blocks. However, prolonged motor blockade is associated with a clinically important risk of fall. With the advent of ultrasonography, the adductor canal can be easily visualized at the mid-thigh level, allowing perform-ance of Adductor Canal Block (ACB) with a high success rate.
Aim: To compare the safety and efficacy of ultrasound guided adductor canal block versus ultrasound guided femoral nerve block as post-operative analgesic in patients undergoing knee arthroscopy.
Patients and Methods: This study was carried out in Tanta University Hospitals from September 2015 till March 2016 on 105 adult patients of both sexes with ASA physical status I/II scheduled for knee arthroscopy. Patients divided into three equal groups (Group I) received basic analgesia in the form of paracetamol and diclofenac, (Group II) received ultrasound guided FNB and (Group III) received ultrasound guided ACB.
Results: There were no significant differences among the three studied groups according to demographic data. Compar-ison of the mean value of NPS score showed no significant difference between FNB and ACB, but there were significant increase in control group in comparison to both FNB and ACB. The first time to introduce morphine and total morphine consumption showed no significant difference between FNB and ACB. There was significant decrease of BBS score in FNB till 6-8h postoperative in comparison with control group and ACB.
Conclusion: Ultrasound guided adductor canal block is efficient as ultrasound guided femoral nerve block in control post-operative pain in patients undergoing knee arthroscopy. Also ACB result in early mobilization with no risk of fall that renders ACB preferred.