Periarticular Injection vs Psoas Block for THA-Associated Postoperative Pain
A number of regional anesthesia modalities, such as psoas compartment block and periarticular injection, have become mainstays of multimodal approaches used during total hip arthroplasty.
Intraoperative periarticular local anesthetic infiltration (periarticular injection) and psoas compartment block (PCB) may provide comparable analgesia after total hip arthroplasty (THA), according to a prospective clinical trial published in The Journal of Arthroplasty.
A number of regional anesthesia modalities, such as PCB and periarticular injection, have become mainstays of multimodal approaches used during THA.
However, the most efficacious method for reducing patient pain postoperatively has remained unclear, prompting investigators to examine what differences, if any, exist between PCB and periarticular injection, in the first study directly comparing them.
In this study, 99 patients with osteoarthritis undergoing unilateral THA by the direct anterior approach by a single surgeon were enrolled between May 2016 and May 2017. Participants in both groups had comparable demographic variables and demonstrated no differences in preoperative resting or ambulatory pain scores. Individuals were randomly assigned to receive PCB (n=49) or periarticular injection (n=50).
The study's primary outcomes were resting and ambulatory postoperative pain scores, reported with the 10-point visual analog scale. The secondary outcome was total inpatient narcotic consumption, reported as an oral morphine equivalent.
The periarticular injection group reported lower resting pain scores at 3 hours postsurgery (2.9±2.2 vs 4.0±2.2; P = .036). Resting and ambulatory pain at postoperative days 1 and 2 and at the 3-week follow-up as well as inpatient total narcotic consumption were comparable in both groups. A composite measure of recovery quality (40 composite score; range, 40-200) was higher in the periarticular injection group vs the PCB group (183.1 ± 10.3 vs 177.2 ± 14.0, respectively; P =.020).
Complications were limited and minor, with transient numbness being the only complaint. There were 5 patients (10.2%) in the PCB group who reported this issue, and 1 patient (2.0%) from the periarticular injection group who experienced the same. No complete motor blockade was observed in either group.
Study strengths included prospective randomization, anesthetic technique specificity and reproducibility, and use of 1-month postoperative pain scores. The study was conducted by a single surgeon, a limitation that may affect generalizability of the results.
Both periarticular injection and PCB provided analgesia following surgery, with similar findings regarding 10-point pain scores and narcotic consumption. The slight superiority of periarticular analgesia during the immediate postoperative period, coupled with the concern for overblockade effects in PCB, contribute to recommending periarticular injection as the preferred anesthetic technique for use during THA.
Fahs AM, Koueiter DM, Kurdziel MD, Huynh KA, Perry CR, Verner JJ. Psoas compartment block vs periarticular local anesthetic infiltration for pain management after anterior total hip arthroplasty: a prospective, randomized study [published online February 20, 2018]. J Arthroplasty. doi:10.1016/j.arth.2018.02.052