Opioid-dependent patients have worse outcomes before knee replacement surgery

Patients who are dependent on opioids (narcotic pain relievers) for pain management before knee replacement surgery have much more difficulty recovering, a study recently published in the Journal of Bone and Joint Surgery (JBJS) has found. These patients tend to have longer hospital stays, more post-surgical pain, a higher rate of complications, and are more likely to need additional procedures, than patients who are not opioid-dependent.

"We expected to find that the opioid-dependent patients have worse outcomes," says orthopaedic surgeon Michael A. Mont, M.D., the principal investigator and Director of the Center for Joint Preservation and Reconstruction at the Rubin Institute for Advanced Orthopaedics at Sinai Hospital of Baltimore. "But the differences between the two groups of patients were even greater than we thought they would be. The chronic narcotics users did significantly worse in every category."

Study Findings:

Patients included in the study were matched according to age, sex, body-mass index, insurance type, as well as a variety of medical factors. When those factors were accounted for, the study still found that chronic opioid users:

• had to remain in the hospital longer after surgery
• were more likely to need referrals for pain management
• were more likely to suffer unexplained pain or stiffness
• had lower function and less motion in the replaced knee

"This doesn't mean that opioid users shouldn't have the surgery," Mont says. "But those patients and their physicians should know that their results may not be as optimal. It might be possible that we can work with these patients to improve their surgical outcomes."

Dr. Mont and his co-authors outline several strategies to help improve patient outcomes; including:

• weaning patients off strong opioid medications prior to surgery
• prescribing alternate, non-opioid pain medications
• considering non-pharmaceutical pain management strategies

The study's authors acknowledge that some patients who become dependent on opioids before surgery may have lower pain thresholds than those who do not. In addition, those patients may be less compliant with rehabilitation plans and other post-surgical treatments. However, the results of this study are important enough to warrant attention to this issue.

"Previous studies have found that patients who use opioids are more dissatisfied after surgery," Mont says. "But these are more powerful findings since patients require additional surgeries. This is a topic our orthopaedic community and other care providers need to address together."