Marijuana Users Had Higher Hip Dislocation Rates After Hip Replacement Surgery

Among 1,654 matched pairs of marijuana users and non-users who underwent total hip arthroplasty (2010-2018), marijuana users had significantly higher rates of hip dislocation at both 90 days and one year. However, there was no difference in opioid consumption between groups. Marijuana use was associated with lower 90-day care costs.

Retrospective review of the Mariner insurance database (2010-2018). Marijuana users identified by ICD codes were 1:1 matched to non-users on age, sex, comorbidities, obesity, alcohol, tobacco, illicit drug use, drug abuse history, and psychiatric history. Compared 90-day and 1-year outcomes.

The finding that marijuana use did not increase opioid consumption challenges the common assumption that cannabis users need more pain medication postoperatively. The dislocation finding may relate to balance or coordination effects rather than surgical healing.

This adds to the surgical outcomes literature showing cannabis-associated complications that may relate to physical function (falls, coordination) rather than wound healing or infection.

Administrative database with ICD coding for marijuana use likely captures only diagnosed cannabis use disorder. Cannot distinguish active use from historical use. Cannot control for factors not captured in claims data. Dislocation mechanism not specified.