Comparative study between adductor canal blockade and the use of spinal morphine to evaluate postoperative analgesia in anterior cruciate ligament reconstruction surgeries

The anterior cruciate ligament is an important reducer of rotational instability of the knee. Its injury is quite common, with arthroscopic surgery with autografts as the technique of choice for treatment. Anesthesia aims to relieve peri and postoperative pain, providing early discharge, rehabilitation and less abuse of analgesic medications. Currently, several anesthetic modalities are used, with no consensus on technical superiority. This is a randomized, double-blind, controlled clinical trial whose main objective was to compare two anesthesias for ligament reconstruction surgery: spinal anesthesia associated with ultrasound block of the adductor canal (group R0,5%) vs. spinal anesthesia associated with intrathecal administration of morphine (group M). Side effects such as paresthesia, urinary retention, headache, pruritus, and tingling were also studied. There was no predominance of adverse effects in the comparison between group M and R0.5% (P = 0.101) and groups R0.5 and C (P = 0.272). The use of opioids in the postoperative period was higher in the control group when compared to the group that underwent adductor canal block, 9 vs. 5 patients, respectively (p = 0.030), but with no differences between the other comparisons. Regardless of the technique used for postoperative pain control, patient satisfaction was 100%. No patient presented serious adverse effects during the study period. In our study, the side effects were close to those found in the literature. Therefore, this study demonstrated that for anterior cruciate ligament reconstruction surgery, both analgesic techniques can be used.