The psoas compartment block (PCB) or periarticular soft-tissue local anesthetic injection are forms of regional anesthesia often used as one of the components in multimodal anesthesia applied during total hip arthroplasty (THA). The most efficacious form of regional anesthesia for THA has yet to be determined.
In a single-surgeon, prospective, clinical trial, patients undergoing THA via direct anterior approach were randomized to receive an intraoperative periarticular local anesthetic infiltration (periarticular injection) or a PCB. Postoperative pain scores, narcotic consumption, and complications were recorded.
Forty-nine patients were randomized to the PCB and 50 were randomized to the periarticular injection. The resting pain score 3 hours postoperatively was statistically significantly lower in the periarticular injection group by 1.1 point (2.9 ± 2.2 vs 4.0 ± 2.2, P = .036). No difference was found in resting pain scores or ambulatory pain scores in the morning or evening of postoperative day 1, 2, or at the 3-week follow-up visit. There was no difference in in-hospital narcotic consumption between groups (P = 1.0). There were no major complications directly related to the block in either group. A total of 6 patients reported complaints of transient numbness, 5 in the PCB group (5/49, 10.2%), and one in the periarticular injection group (1/50, 2%, P = .087).
These results demonstrate similarity between the 2 methods. We prefer periarticular anesthetic infiltration over PCB due to improved immediate postoperative pain scores and avoidance of potential symptoms associated with nerve blockade.