Proponents of the direct anterior approach (DAA) for hip arthroplasty (THA) claim lower postoperative pain compared to the posterolateral approach (PA); however, whether that theoretical advantage results in lower opioid consumption is unclear. We sought to investigate the relationship between the DAA and PA on total 90-day predicted opioid consumption in a large cohort.

Retrospective analysis identified 2,304 DAA and 6,288 PA primary THAs in patients >18 years old from February 2019 to April 2022. Ninety-day postoperative total morphine milligram equivalent (MME); in-hospital administration, discharge prescriptions, and refills within 90 days were compared between DAA and PA cohorts. Nearest-neighbor matching was performed controlling for age, sex, BMI, ASA, and periarticular injection to evaluate opioid consumption patterns for DAA and PA. Quantile regression was employed to predict the median (50th percentile) MME prescribed by surgical approach.

After matching, DAA and PA demonstrated similar median total 90-day prescribed MME (p = 0.008). After adjusting for patient and surgical factors, quantile regression predicted a similar median total 90-day prescribed MME for DAA and PA (243.5 versus 242.7; p = 0.78). While approach did not demonstrate a significant relationship for predicted 90-day MME, other factors including age, sex, BMI, length of stay, peripheral anesthesia, periarticular injection, and white or Caucasian race demonstrated a significant relationship with predicted 90-day MME (p <0.0001).

While we identified several risk factors for increased in-hospital and 90-day post-operative opioid consumption, a comparison between DAA and PA did not demonstrate significantly different opioid prescribing patterns.