The pericapsular nerve group block: a step towards outpatient total hip arthroplasty?

A new regional anaesthetic technique, coined the pericapsular nerve group (PENG) block, targets the anterior hip capsule by blocking the articular branches of the femoral nerve and accessory obturator nerve. In this study, we evaluated: (1) patient outcomes; (2) postoperative pain scores; and (3) postoperative opioid consumption in total hip arthroplasty (THA) patients who received a PENG block in comparison to a control group.

A retrospective chart review was performed for patients who underwent primary THA and met criteria at a single institution (n = 48), with an additional cohort of patients collected as controls (n = 48). Postoperative pain scores were measured by obtaining the cumulative visual analogue scores (VAS) at 12-hour intervals until the 48-hour benchmark. All administered opioids were collected from postoperative day (POD) 0 to POD2 and converted to morphine milligram equivalents (MME).

In the PENG group, length of stay was significantly shorter (p < 0.001) and the initial postoperative distance walked was significantly farther (p = 0.001). The PENG group consistently demonstrated significantly lower mean cumulative pain scores until the 48-hour mark (p < 0.001 for all). Patients receiving the PENG block also experienced a significantly longer therapeutic window before requiring their first opioid (p < 0.002). The PENG group required significantly less opioid MMEs on POD1, POD2, and cumulatively over the entire stay (p < 0.022 for all).

Our findings suggest that the PENG block has the potential of impacting THA recovery pathways and contributing to cost savings. Thus, its use further supports the transition to the outpatient setting and drives us towards achieving value-driven healthcare.