# Adductor Canal Block Versus Femoral Nerve Block for Postoperative Pain Management in Anterior Cruciate Ligament Reconstruction: A Prospective Interventional Study

## TL;DR

This study compares two nerve blocks for pain management after ACL surgery, finding that one preserves muscle strength better than the other.

## Contribution

The study provides new evidence comparing the effectiveness of adductor canal block versus femoral nerve block in preserving motor function after ACL reconstruction.

## Key findings

- ACB and FNB provided similar durations of analgesia (348.33 vs. 363.06 minutes).
- ACB preserved motor strength better, with 12 out of 15 patients experiencing no motor block.
- No neurological adverse effects were observed in either group.

## Abstract

Background

A common knee joint disorder is injury to the anterior cruciate ligament (ACL), which often requires surgery. Proper pain control after the surgery facilitates fast recovery and prevents chronic pain. To provide analgesia for knee procedures, the use of opioids, non-steroidal anti-inflammatory medications, and regional techniques are commonly employed. This study aims to evaluate the efficacy of adductor canal block (ACB) and femoral nerve block (FNB) for postoperative pain management after anterior cruciate ligament reconstructions (ACLRs).

Methodology

This prospective interventional study included 30 participants scheduled for patellar graft ACLR. They were assigned into groups, i.e., ACB and FNB, with 15 patients each. The evaluation occurred one day before the operation, and all surgical procedures were performed using spinal anesthesia. During the postoperative period, a 10-point visual analog scale (VAS) was utilized to quantify pain intensity at the end of the surgery and at various intervals after the surgery. Patients with a VAS score greater than 4 received either FNB or ACB using bupivacaine 0.125%. Duration of analgesia time, power of quadriceps muscle, and neurologic complications were documented.

Results

No statistically significant value was observed in the mean duration of analgesia between the patients in ACB (348.33 minutes) and the patients in FNB (363.06 minutes). No motor block was observed in 12 patients who received ACB, while only four patients had a motor-sparing effect among those who received FNB. No neurological adverse effects were observed in the study participants.

Conclusions

ACB provides an equal duration of analgesia similar to FNB, and ACB significantly spares motor strength and maintains higher quadriceps power than FNB.