Total knee arthroplasty (TKA) is effective for relieving pain for patients with knee osteoarthritis but research suggests that preoperative opioid use may worsen outcomes following surgery.
Researchers collected medical data from patients before and six months after TKA and used the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) to quantify pain.
Of 156 patients, 36 had had at least one preoperative opioid prescription. The mean baseline WOMAC score was 43.0 for the non-opioid group and 46.9 points for those who had used opioids. After six months, the opioid group had a mean reduction in WOMAC score of 27.0 points (95% confidence interval [CI] = 22.7 to 31.3) compared with 33.6 points (95% CI = 31.4–35.9) in the non-opioid group.
Reporting in The Journal of Bone and Joint Surgery (online, 17 May 2017), the researchers conclude that patients who used opioids before TKA obtained less pain relief, and recommend that clinicians consider limiting pre-TKA opioid use to optimise the benefits of TKA
 Smith S, Bido J, Collins J et al. Impact of preoperative opioid use on total knee arthroplasty outcomes. J Bone Joint Surg Am. 2017;99:803–808. doi: 10.2106/JBJS.16.01200