Factors associated with persistent opioid use 6–12 months after primary total knee arthroplasty

Perioperative Opioid Use and Dosage Trajectories Vary Depending on Pain Outcome Classification and Bodily Pain in Patients who Catastrophize About Their Pain: A Secondary Analysis of a Randomized Trial in Knee Arthroplasty

Opioid use and dosage following knee arthroplasty (KA) has not been reported for subgroups with persistent moderate pain versus rapidly improving mild pain, externally validated from prior work. We determined if opioid use and dosage varied for persons classified into these externally validated subgroups. A secondary purpose determined if bodily pain scores are associated with the outcome subgroup. This was a secondary analysis of a prospective no-effect randomized clinical trial conducted on 384 participants with pain catastrophizing and scheduled for KA. Data were collected preoperatively and at 2-, 6-, and 12-month following surgery. Two-piece latent class growth curve analyses applied previously validated pain outcomes to determine subgroup outcome trajectories for the proportion of opioid users and oral morphine equivalent (OME) dosages. Substantial trajectory separation was found for opioid use and OME. Specifically, the average OME dosage for the persistent moderate pain subgroup was more than double that for the other outcome subgroup. The average preoperative opioid daily OME dosage for 170 patients reporting opioid use was 24.94 (95% [confidence interval] CI = 20.52, 29.38). Bodily pain was consistently higher for the persistent moderate pain subgroup compared to the other subgroup. Outcome subgroups in patients with pain catastrophizing demonstrated substantial differences in opioid use and dosage and were predicted by high pain catastrophizing, more bodily pain, and changes in bodily pain over time. The persistent moderate pain subgroup is at greater risk of opioid use and greater opioid dosages and should be targeted for preoperative screening and interventions to reduce opioid use and potential opioid misuse. PERSPECTIVE: More frequent and higher opioid dosage following KA was found for the persistent moderate pain subgroup compared to the other subgroup. Patients with persistent pain had worse catastrophizing, contralateral and ipsilateral lower extremity pain, low back pain, and whole body pain compared to the rapidly improving mild pain subgroup.

Advances in the management of persistent pain after total knee arthroplasty

PURPOSE OF REVIEW

Total knee arthroplasty (TKA) is one of the most commonly performed surgical procedures, with additional growth anticipated as the US population ages. Because the prevalence of chronic postsurgical pain ranges from 15 to 25%, identifying persons at risk for persistent pain following surgery allows for preoperative optimization of risk factors as well as early identification and intervention in the postsurgical period.

RECENT FINDINGS

Clinical understanding of available management techniques is critical to management, which should focus on improving patient mobility and satisfaction while reducing patient disability and healthcare costs. Current evidence supports a multimodal management strategy. This includes pharmacologic and nonpharmacologic interventions, procedural techniques, and identification and optimization of psychosocial and behavioral contributors to chronic pain. Procedural techniques known to confer analgesia include radiofrequency and watercooled neurotomy techniques. More recently, case reports have been published describing analgesic benefit with central or peripheral neuromodulation as a novel, though more invasive analgesic therapy.

SUMMARY

Identification and early intervention to address persistent pain after TKA is important to optimize patient outcomes. The anticipated growth in TKA underscores the need for future investigations to more fully define potential therapies for chronic pain following TKA.

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

Osteoarthritis as an Umbrella Term for Different Subsets of Humans Undergoing Joint Degeneration: The Need to Address the Differences to Develop Effective Conservative Treatments and Prevention Strategies

Osteoarthritis (OA) of joints such as the knee and hip are very prevalent, and the number of individuals affected is expected to continue to rise. Currently, conservative treatments after OA diagnosis consist of a series of increasingly invasive interventions as the degeneration and pain increase, leading very often to joint replacement surgery. Most interventions are focused on alleviating pain, and there are no interventions currently available that stop and reverse OA-associated joint damage. For many decades OA was considered a disease of cartilage, but it is now considered a disease of the whole multi-tissue joint. As pain is the usual presenting symptom, for most patients, it is not known when the disease process was initiated and what the basis was for the initiation. The exception is post-traumatic OA which results from an overt injury to the joint that elevates the risk for OA development. This scenario leads to very long wait lists for joint replacement surgery in many jurisdictions. One aspect of why progress has been so slow in addressing the needs of patients is that OA has been used as an umbrella term that does not recognize that joint degeneration may arise from a variety of mechanistic causes that likely need separate analysis to identify interventions unique to each subtype (post-traumatic, metabolic, post-menopausal, growth and maturation associated). A second aspect of the slow pace of progress is that the bulk of research in the area is focused on post-traumatic OA (PTOA) in preclinical models that likely are not clearly relevant to human OA. That is, only ~12% of human OA is due to PTOA, but the bulk of studies investigate PTOA in rodents. Thus, much of the research community is failing the patient population affected by OA. A third aspect is that conservative treatment platforms are not specific to each OA subset, nor are they integrated into a coherent fashion for most patients. This review will discuss the literature relevant to the issues mentioned above and propose some of the directions that will be required going forward to enhance the impact of the research enterprise to affect patient outcomes.