A Comparison of a Single Point versus Two-Point Injection Technique to Block Sciatic Nerve by Posterior Approach Using Sono Guidance: A Randomized Controlled Trial

Abstract

Background: Sciatic nerve blocks are essential for effective pain management in lower limb surgeries. This study compares the efficacy and duration of analgesia between single-point and two-point ultrasound-guided injection techniques for sciatic nerve blocks.

Methods: This randomized controlled trial was conducted at Dr. Sampurnanand Medical College, involving 100 patients undergoing below-knee surgeries. Participants were allocated to either the single-point injection group (SP) or the two-point injection group (DP) through randomization. The primary outcomes measured were the time to perform the block, onset times of sensory and motor blockade, duration of analgesia, and procedural complications.

Results: The time to perform the block was shorter in the SP group (9.97 ± 1.03 minutes) compared to the DP group (15.69 ± 1.49 minutes; p<0.001). However, the DP group exhibited faster onset of sensory (11.14 ± 1.62 minutes) and motor blockade (15.73 ± 1.44 minutes) and a longer duration of analgesia (421.80 ± 34.39 minutes), all statistically significant compared to the SP group.

Conclusion: The two-point injection technique, while more time-consuming, enhances the effectiveness of sciatic nerve blocks by providing a quicker onset and prolonged duration of analgesia compared to the single-point technique. These findings suggest that the two-point technique may be preferable for surgeries requiring extended postoperative pain management.