Should Cannabinoids Be Added to Multimodal Pain Regimens After Total Hip and Knee Arthroplasty?

This study investigated the effects of dronabinol on pain, nausea, and length of stay following total joint arthroplasty (TJA).

We retrospectively compared 81 consecutive primary TJA patients who received 5 mg of dronabinol twice daily in addition to a standard multimodal pain regimen with a matched cohort of 162 TJA patients who received only the standard regimen. A single surgeon performed all surgeries. Patient demographics, length of stay, opioid morphine equivalents (MEs) consumed, reports of nausea/vomiting, discharge destination, distance walked in physical therapy, and visual analog scale pain scores were collected for both groups. Student's t-tests as well as chi-square or Mann-Whitney U-tests were used for statistical comparisons.

There were no significant differences between the 2 groups for age, gender, body mass index, American Society of Anesthesiologists score, anesthesia type, visual analog scale scores, distance walked with physical therapy, discharge disposition, or episodes of nausea/vomiting. The mean length of stay in the dronabinol group was significantly shorter at 2.3 ± 0.9 days versus 3.0 ± 1.2 days in the control group (P = .02). In the context of a shorter stay, the dronabinol group consumed significantly fewer total MEs (252.5 ± 131.5 vs 313.3 ± 185.4 mg, P = .0088). Although the dronabinol group consumed fewer MEs per day and per length of stay on average, neither of these achieved statistical significance. No side effects of dronabinol were reported.

These findings suggest that further investigation into the role of cannabinoid medications for non-opioid pain control in the post-arthroplasty patient may hold merit.