A combination of high preoperative pain and low radiological grade of arthritis is associated with a greater intensity of persistent pain 12 months after total knee arthroplasty

The evolution of anesthetic management for total knee arthroplasty (TKA) patients: A hospital network experience

Introduction

In the face of an ongoing opioid epidemic and an aging population, the utilization of a successful multimodal pain regimen in patients undergoing total knee arthroplasty (TKA) is vital. This study looks to explore the effect of different types of anesthesia in addition to a multimodal pain regimen on post-operative outcomes after undergoing TKA.

Materials and methods

From January 2016 to December 2022, 783 charts of patients undergoing an elective TKA were reviewed. Patients undergoing primary, isolated, and unilateral TKA procedures were included. Patients were grouped into three study arms: 1) general anesthesia (GA); 2) general anesthesia with a local anesthetic adductor canal block (GA + ACB); 3) spinal anesthesia with local anesthetic adductor canal block (SA + ACB). Patients who received other anesthesia types or received ACB utilizing liposomal bupivacaine were excluded.

Results

Of the 420 included patients, 63 patients received GA, 148 GA + ACB, and 209 SA + ACB. Patients in the SA + ACB group had a shorter LOS compared to both the GA + ACB and GA groups (p < 0.01. The SA + ACB group had the lowest daily average OME requirement (p < 0.01). Finally, patients in the SA + ACB group had the lowest average total cost of $11,683.91 (p < 0.01).

Discussion

Spinal anesthesia with adductor canal block is effective in decreasing opioid usage and improving postoperative outcomes after TKA. Surgeons and anesthesiologists should look to utilize this anesthetic option along with a multimodal regimen when deciding how to best manage postoperative pain after TKA procedures.

Level of evidence

Level III.

Chronic pain at 1-year following knee arthroplasty is associated with a worse joint-specific function and health-related quality of life

PURPOSE

The purpose of this study was to identify independent variables associated with chronic pain (CP) at 1 year following knee arthroplasty (KA) and whether this influenced functional outcomes.

METHODS

This retrospective study was conducted over a 2-year period and included 2588 patients with completed Oxford knee score (OKS) and EuroQol (EQ)-five domains (5D) preoperatively and at 1 and 2 years postoperatively. The OKS pain component score was used to define patients with CP (≤14 points). The mean age was 70.0 (range 34-94) years and there were 1553 (60.0%) females.

RESULTS

There were 322 (12.4%) patients with CP at 1 year. A worse preoperative EQ-5D (p = 0.025), EQ-visual analogue scale (VAS) (p = 0.005) and OKS questions relating to washing (p = 0.010), limping (p = 0.007), kneeling (p = 0.003) and night pain (p = 0.004) were independently associated with risk of CP. However, the preoperative OKS (area under the curve [AUC]: 72.0, p < 0.001) and EQ-5D score (AUC: 70.1, p < 0.001) were the most reliable predictors, with threshold values of <18-points and <0.300 being predictive of CP, respectively. Of those with CP at 1 year, 231 were followed up at 2 years, of which 92 (39.8%) had resolution of their CP. A worse response to OKS question 11 (ability to shop) and EQ-5D (p = 0.028) at 1 year was independently associated with persistent CP. Patients with CP had significantly (p < 0.001) worse OKS, EQ-5D and EQ-VAS at 1 year compared to those without. However, for those that had resolution of their CP at 2 years, their outcomes were clinically equal to those that did not have CP at 1 year.

CONCLUSION

One in eight patients had CP at 1 year following surgery, which was associated with clinically worse knee-specific outcomes and quality of life. However, by 2 years, two in five patients had resolution of their CP and had functional outcomes clinically equal to those without CP at 1 year. The risk factors identified could be used to inform patients of their risk for CP and the potential for resolution.

LEVEL OF EVIDENCE

Level III retrospective study.

Linking Intra-Articular Inflammatory Biomarkers with Peripheral and Central Sensitization in Late-Stage Knee Osteoarthritis Pain: A Pilot Study

Background/Objectives: To investigate if intra-articular biomarkers relate to peripheral and central sensitization in patients with late-stage knee osteoarthritis (KOA). Methods: A total of 17 (6M, 11F) patients (aged 69 ± 10 years) were assessed for peripheral (pressure pain thresholds (PPT)) and central (temporal summation (TS) and conditioned pain modulation (CPM)) sensitization the day before total knee arthroplasty. Synovial fluid was collected during surgery and assayed for IL-6, IL-8, IL-10, TNF-α, CXCL-10, BDNF, NGF, CCL2, CCL5, VEGF, IL-1RI, MMP-1, MMP-7, IL-1β, and CXCL-9. Associations of biomarkers and their combinations reflecting chronic (CXCL-9) and acute ((CCL2×CXCL-10)/IL-10)) inflammation, cartilage degeneration (MMP-1×MMP-7), and neurotrophy (NGF×BDNF) with PPT, TS, and CPM were analyzed by bivariate correlations and by multiple linear regression analyses corrected for BMI, sex, and age. Results: The medial joint line and the superior medial joint region showed the lowest PPT. Higher acute inflammation related significantly to worse pressure tenderness at the superior medial joint region (R2 = 0.642; p = 0.010). Cartilage degeneration and chronic inflammation were associated with both absolute (R2 = 0.827; p = 0.001) and relative CPM (R2 = 0.882; p < 0.001). Acute inflammation and neurotrophy were related to relative TS at the m. tibialis anterior (R2 = 0.728; p = 0.02). Conclusions: This study demonstrates that increased levels of intra-articular biomarkers of acute inflammation are related to peripheral sensitization and that biomarkers of cartilage degeneration and chronic inflammation are associated with central sensitization. These results may be a stepping-stone toward a better understanding of the working mechanism of peripheral and central sensitization in KOA pain and the development of more targeted therapeutic interventions.

Bibliometric and visual analysis of research on analgesia and total knee arthroplasty from 1990 to 2022

Background

In recent decades, there have been notable advancements in the field of analgesia and total knee arthroplasty (TKA). This study aims to employ bibliometric analysis to elucidate the prevailing research focal points and trends within analgesia and TKA from 1990 to 2022.

Material and methods

Relevant publications were retrieved from the Web of Science Core Collection. CiteSpace, VOSviewer, and Scimago Graphica were used for visualization and bibliometric analysis of countries, institutions, authors, journals, references, and keywords.

Results

A total of 2776 publications on analgesia and TKA were identified, with the United States having the highest number of publications. The University of Copenhagen was the most productive institution, and Kehlet, Henrik was the most prolific author. The Journal of Arthroplasty had the most publications and citations. The most common keywords were "TKA," "pain management," "postoperative pain," "Total hip arthroplasty (THA)," and "postoperative management." Keyword burst detection demonstrated that adductor canal block (ACB) was a recent research hotspot.

Conclusion

Our study revealed a sharp increase in global publications on analgesia and TKA, and this trend is expected to continue. Further research is necessary to determine the optimal regimen for multimodal analgesia, the ideal location and volume of ACB, and their clinical significance.

Factors associated with pain and functional impairment five years after total knee arthroplasty: a prospective observational study

BACKGROUND

Few studies have evaluated the associations between preoperative factors and pain and physical function outcomes after total knee arthroplasty (TKA) from a mid-term perspective. Identification of such factors is important for optimizing outcomes following surgery. Thus, we examined the associations between selected preoperative factors and moderate to severe pain and pain-related functional impairment as measured using the Brief Pain Inventory (BPI), five years after TKA in patients with knee osteoarthritis.

METHODS

In this prospective observational study, all patients scheduled for primary unilateral TKA for osteoarthritis were consecutively recruited. Preoperative factors identified from previous meta-analyses were included to assess their associations with pain severity and pain-related functional impairment five years after TKA. Pain severity was the primary outcome, while pain-related functional impairment was the secondary outcome. The BPI was used to evaluate outcomes five years post-TKA. Statistically significant factors from univariate regressions were entered into a multiple logistic regression model to identify those with the strongest associations with pain severity or pain-related functional impairment five years after TKA.

RESULTS

A total of 136 patients were included, with a mean age of 67.7 years (SD 9.2) and a majority being female (68%). More severe preoperative pain (OR = 1.34, 95% CI [1.03 to 1.74]), more painful sites (OR = 1.28., 95% CI [1.01 to 1.63]), and more severe anxiety symptoms (OR = 1.14., 95% CI [1.01 to 1.28]) were associated with increased likelihood of moderate to severe pain five years after TKA surgery, while more severe osteoarthritis (OR = 0.13, 95% CI [0.03 to 0.61]) was associated with reduced likelihood of moderate to severe pain five years after TKA. More severe anxiety symptoms (OR = 1.25, 95% CI [1.08 to 1.46]) were also associated with increased likelihood of moderate to severe pain-related functional impairment five years after surgery, while male sex (OR = 0.23, 95% CI [0.05 to 0.98]) was associated with reduced likelihood of pain-related functional impairment five years after surgery.

CONCLUSION

The identified preoperative factors should be included in larger prognostic studies evaluating the associations between preoperative factors and mid-term pain severity and physical function outcomes after TKA surgery.

Do the Revision Rates of Arthroplasty Surgeons Correlate With Postoperative Patient-reported Outcome Measure Scores? A Study From the Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

Patient-reported outcome measures (PROMs) are a pragmatic and efficient means to evaluate the functional quality of arthroplasty beyond revision rates, which are used by most joint replacement registries to judge success. The relationship between these two measures of quality-revision rates and PROMs-is unknown, and not every procedure with a poor functional result is revised. It is logical-although still untested-that higher cumulative revision rates correlate inversely with PROMs for individual surgeons; more revisions are associated with lower PROM scores.

QUESTIONS/PURPOSES

We used data from a large national joint replacement registry to ask: (1) Does a surgeon's early THA cumulative percent revision (CPR) rate and (2) early TKA CPR rate correlate with the postoperative PROMs of patients undergoing primary THA and TKA, respectively, who have not undergone revision?

METHODS

Elective primary THA and TKA procedures in patients with a primary diagnosis of osteoarthritis that were performed between August 2018 and December 2020 and registered in the Australian Orthopaedic Association National Joint Replacement Registry PROMs program were eligible. THAs and TKAs were eligible for inclusion in the primary analysis if 6-month postoperative PROMs were available, the operating surgeon was clearly identified, and the surgeon had performed at least 50 primary THAs or TKAs. Based on the inclusion criteria, 17,668 THAs were performed at eligible sites. We excluded 8878 procedures that were not matched to the PROMs program, leaving 8790 procedures. A further 790 were excluded because they were performed by unknown or ineligible surgeons or were revised, leaving 8000 procedures performed by 235 eligible surgeons, including 4256 (53%; 3744 cases of missing data) patients who had postoperative Oxford Hip Scores and 4242 (53%; 3758 cases of missing data) patients who had a postoperative EQ-VAS score recorded. Complete covariate data were available for 3939 procedures for the Oxford Hip Score and for 3941 procedures for the EQ-VAS. A total of 26,624 TKAs were performed at eligible sites. We excluded 12,685 procedures that were not matched to the PROMs program, leaving 13,939 procedures. A further 920 were excluded because they were performed by unknown or ineligible surgeons, or because they were revisions, leaving 13,019 procedures performed by 276 eligible surgeons, including 6730 (52%; 6289 cases of missing data) patients who had had postoperative Oxford Knee Scores and 6728 (52%; 6291 cases of missing data) patients who had a postoperative EQ-VAS score recorded. Complete covariate data were available for 6228 procedures for the Oxford Knee Score and for 6241 procedures for the EQ-VAS. The Spearman correlation between the operating surgeon's 2-year CPR and 6-month postoperative EQ-VAS Health and Oxford Hip or Oxford Knee Score was evaluated for THA and TKA procedures where a revision had not been performed. Associations between postoperative Oxford and EQ-VAS scores and a surgeon's 2-year CPR were estimated based on multivariate Tobit regressions and a cumulative link model with a probit link, adjusting for patient age, gender, ASA score, BMI category, preoperative PROMs, as well as surgical approach for THA. Missing data were accounted for using multiple imputation, with models assuming they were missing at random and a worst-case scenario.

RESULTS

Of the eligible THA procedures, postoperative Oxford Hip Score and surgeon 2-year CPR were correlated so weakly as to be clinically irrelevant (Spearman correlation ρ = -0.09; p < 0.001), and the correlation with postoperative EQ-VAS was close to zero (ρ = -0.02; p = 0.25). Of the eligible TKA procedures, postoperative Oxford Knee Score and EQ-VAS and surgeon 2-year CPR were correlated so weakly as to be clinically irrelevant (ρ = -0.04; p = 0.004 and ρ = 0.03; p = 0.006, respectively). All models accounting for missing data found the same result.

CONCLUSION

A surgeon's 2-year CPR did not exhibit a clinically relevant correlation with PROMs after THA or TKA, and all surgeons had similar postoperative Oxford scores. PROMs, revision rates, or both may be inaccurate or imperfect indicators of successful arthroplasty. Missing data may limit the findings of this study, although the results were consistent under a variety of different missing data scenarios. Innumerable factors contribute to arthroplasty results, including patient-related variables, differences in implant design, and the technical quality of the procedure. PROMs and revision rates may be analyzing two different facets of function after arthroplasty. Although surgeon variables are associated with revision rates, patient factors may exert a stronger influence on functional outcomes. Future research should identify variables that correlate with functional outcome. Additionally, given the gross level of function that Oxford scores record, outcome measures that can identify clinically meaningful functional differences are required. The use of Oxford scores in national arthroplasty registries may rightfully be questioned.

LEVEL OF EVIDENCE

Level III, therapeutic study.

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.

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.