Lifetime medical costs of knee osteoarthritis management in the United States: impact of extending indications for total knee arthroplasty

Efficacy and safety of biologic agents for the treatment of osteoarthritis: a meta-analysis of randomized placebo-controlled trials

Background:

We aimed to evaluate the efficacy and safety of biologic agents targeting three main cytokines, that is, nerve growth factor (NGF), interleukin-1 (IL-1), and tumor necrosis factor-α (TNF-α), for osteoarthritis (OA) treatment.

Methods:

Databases (PubMed, Embase, and Cochrane Library) and ClinicalTrials.gov were systematically searched for randomized placebo-controlled trials (RCTs) of biologic agents from inception to November 15, 2020. The outcomes were the mean change in pain, function scores, and the risk of adverse effects (AEs).

Results:

Out of the 28 studies with 29 RCTs (8555 individuals) included, biologic agents were superior to placebo in pain relief (standardized mean difference [SMD] = 0.28, 95% confidence interval [CI] = 0.17–0.38, p < 0.001) and function improvement (SMD = 0.30, 95% CI = 0.18–0.43, p < 0.001). The incidence of any AEs (risk ratio [RR] = 1.09, 95% CI = 1.05–1.14, p < 0.001) and discontinuations due to AEs (RR = 1.39, 95% CI = 1.05–1.83, p = 0.021) were higher following treatment with biologic agents while no significant difference was found in serious AEs. Subgroup analyses showed that NGF inhibitors provided superior pain relief (SMD = 0.36, 95% CI = 0.26–0.47, p < 0.001) and function improvement (SMD = 0.41, 95% CI = 0.30–0.51, p < 0.001), whereas IL-1 inhibitors and TNF-α inhibitors did not. Meanwhile, NGF inhibitors increased the incidence of any AEs (RR = 1.12, 95% CI = 1.07–1.17, p < 0.001) and discontinuations due to AEs (RR = 1.48, 95% CI = 1.07–2.06, p = 0.018). IL-1 inhibitors and TNF-α inhibitors showed no difference in safety compared with placebo.

Conclusions:

The efficacy and safety of biologic agents vary by mechanism of action. NGF inhibitors can relieve OA-related pain and improve function but involve safety concerns. IL-1 inhibitors and TNF-α inhibitors are relatively safe options but with limited efficacy.

Incorporating patient-reported outcomes into shared decision-making in the management of patients with osteoarthritis of the knee: a hybrid effectiveness-implementation study protocol

INTRODUCTION

Osteoarthritis (OA) is a major clinical and public health concern. The primary surgical treatment of knee OA is total knee replacement (TKR), a procedure that aims to alleviate pain and restore physical function. TKR is expensive, however, and based on professional guidelines, inappropriately performed in up to a third of patients. Patient-reported outcome measures (PROMs) help evaluate treatment options by quantifying health outcomes that matter to patients and can thus inform shared decision-making (SDM) between patients and health professionals.

METHODS AND ANALYSIS

This is a US-based 2-year, two-site hybrid type 1 study to assess clinical effectiveness and implementation of a machine learning-based patient decision aid (PDA) integrating patient-reported outcomes and clinical variables to support SDM for patients with knee OA considering TKR. Substudy 1: At one study site, a randomised controlled trial is evaluating the clinical effectiveness of the PDA and SDM process on decision quality as measured after the baseline consultation and treatment choice measured 3 and 6 months after the baseline visit among 200 patients with knee OA. Substudy 2: At a second study site, a qualitative assessment using principles of behaviour design and intervention mapping is evaluating the feasibility and acceptability of the PROMs, PDA and SDM process by interviewing seven health professionals and 25 patients before and 25 patients after PDA implementation.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from The University of Texas at Austin Institutional Review Board (protocol number: 2018-11-0042). Informed consent will be obtained from all participants. Study results will be disseminated through conference presentations, publications and professional societies.

TRIAL REGISTRATION NUMBER

NCT04805554.

Joint Dysfunctionality Alleviation along with Systemic Inflammation Reduction following Arthrocen Treatment in Patients with Knee Osteoarthritis: A Randomized Double-Blind Placebo-Controlled Clinical Trial

Background and objectives: Many mediators and cytokines are involved in the pathogenesis of osteoarthritis (OA). Some of these cytokines are spontaneously expressed by cultured fibroblast-like synoviocytes. Therefore, using serum samples, the efficacy and the effects of avocado/soy unsaponifiables, ASU, (Arthrocen) on cytokine changes were assessed in patients with knee OA (KOA). Materials and Methods: Experimental procedure: A randomized, double-blind, placebo-controlled clinical trial was conducted on patients with a diagnosis of mild to moderate OA who received either Arthrocen 300 mg/day (n = 61) or placebo (n = 58) for 3 months. Data collection was performed using questionnaires including the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), 20-item short form survey (SF-20), Lequesne index of severity for osteoarthritis of the knee (LISOK), and three visual analog scales (VASs) as pain quality indices. The serum levels of interleukins 2 (IL-2), IL-4, IL-10, IL-17α, and TNF-α were measured using an ELISA reader. Results: Both quality of life indices, pain sensation and scored by specialists (as VASs), respectively, including WOMAC and SF-20, as well as joint dysfunctionality symptoms assessed by physicians were significantly improved (p < 0.05) in OA patients receiving Arthrocen. The serum levels of anti-inflammatory interleukins 4 and 10 were also augmented, while levels of inflammatory IL-17 and TNF-ɑ cytokines were decreased significantly (p < 0.05) compared with the control groups during the 3- and 6-month treatment. Conclusions: Arthrocen consumption may increase the quality of life in OA patients through amelioration of inflammation and improvement of functional activities without any adverse effects in the long term.

Baicalein Alleviates Osteoarthritis Progression in Mice by Protecting Subchondral Bone and Suppressing Chondrocyte Apoptosis Based on Network Pharmacology

As life expectancy increases, Osteoarthritis (OA) is becoming a more frequently seen chronic joint disease. The main characteristics of OA are loss of articular cartilage, subchondral bone sclerosis, and synovial inflammation. Baicalein (Bai), a traditional Chinese medicine extracted from Scutellaria baicalensis Georgi, has been demonstrated to exert notable anti-inflammatory effects in previous studies, suggesting its potential effect in the treatment of OA. In this study, we first predicted the action targets of Bai, mapped target genes related to OA, identified potential anti-OA targets for Bai, performed gene ontology (GO) enrichment, and KEGG signaling pathway analyses of the action targets, and analyzed the molecular docking of key Bai targets. Additionally, the effect and potential mechanism of Bai against OA were verified in mouse knee OA models induced by destabilized medial meniscus (DMM) surgery. GO and KEGG analyses showed that 19 anti-OA targets were mainly involved in the response to oxidative stress, the response to hypoxia and apoptosis, and the PI3K-Akt and p53 signaling pathways. Molecular docking results indicated that BAX, BCL 2, and Caspase 3 enriched in the apoptotic signaling pathway have high binding affinity with Bai. Validation experiments showed that Bai can significantly attenuate the loss of articular cartilage (OARSI score), suppress synovial inflammation (synovitis score), and ameliorate subchondral bone resorption measured by micro-CT. In addition, Bai notably inhibited the expression of apoptosis-related proteins in articular cartilage (BAX, BCL 2, and Caspase 3). By combining network pharmacology with experimental validation, our study identifies and verifies the importance of the apoptotic signaling pathway in the treatment of OA by Bai. Bai may have promising application and potential therapeutic value in OA treatment.

Unraveling the Signaling Secretome of Platelet-Rich Plasma: Towards a Better Understanding of Its Therapeutic Potential in Knee Osteoarthritis

Platelets and their secretory products play an important role in determining the balance between tissue repair and tissue damage. To obtain novel insights into the molecular composition of platelet-rich plasma (PRP) and contextualize them in knee osteoarthritis (OA), two different plasma formulations, namely PRP and platelet-poor plasma (PPP), were prepared from six healthy donors following a biobank-automated protocol. Inter-donor differences were analyzed, and pools were created before performing multiplexing protein arrays. In addition, PRP and PPP were prepared from six patients following our in-house protocols. Supernatants from PRP and PPP were harvested one hour after calcium chloride activation. Multiplexing protein arrays were performed in parallel for all plasma formulations. Results were normalized to fold change in relation to PPP and examined using Ingenuity Pathway Analysis Software. Bioinformatic predictions showed that PRPs constitute a signaling system with interrelated networks of inflammatory and angiogenic proteins, including but not limited to interleukin-6 and -8 (IL-6, IL-8), insulin like growth factor 1 (IGF-1), transforming growth factor beta, (TGF-b), and vascular endothelial growth factor (VEGF) signaling, underlying biological actions. Predictions of canonical systems activated with PRP molecules include various inflammatory pathways, including high-mobility group box protein (HMGB1) and interleukin 17 (IL-17) signaling, neuroinflammation, and nuclear factor-kappa b (NF-κB) pathways. Eventually, according to these predictions and OA evolving knowledge, selected PRP formulations should be tailored to modulate different inflammatory phenotypes, i.e., meta-inflammation, inflame-aging or posttraumatic inflammatory osteoarthritis. However, further research to discriminate the peculiarities of autologous versus allogeneic formulations and their effects on the various OA inflammatory phenotypes is needed to foster PRPs.

Fully Automatic Knee Bone Detection and Segmentation on Three-Dimensional MRI

In the medical sector, three-dimensional (3D) images are commonly used like computed tomography (CT) and magnetic resonance imaging (MRI). The 3D MRI is a non-invasive method of studying the soft-tissue structures in a knee joint for osteoarthritis studies. It can greatly improve the accuracy of segmenting structures such as cartilage, bone marrow lesion, and meniscus by identifying the bone structure first. U-net is a convolutional neural network that was originally designed to segment the biological images with limited training data. The input of the original U-net is a single 2D image and the output is a binary 2D image. In this study, we modified the U-net model to identify the knee bone structures using 3D MRI, which is a sequence of 2D slices. A fully automatic model has been proposed to detect and segment knee bones. The proposed model was trained, tested, and validated using 99 knee MRI cases where each case consists of 160 2D slices for a single knee scan. To evaluate the model's performance, the similarity, dice coefficient (DICE), and area error metrics were calculated. Separate models were trained using different knee bone components including tibia, femur, patella, as well as a combined model for segmenting all the knee bones. Using the whole MRI sequence (160 slices), the method was able to detect the beginning and ending bone slices first, and then segment the bone structures for all the slices in between. On the testing set, the detection model accomplished 98.79% accuracy and the segmentation model achieved DICE 96.94% and similarity 93.98%. The proposed method outperforms several state-of-the-art methods, i.e., it outperforms U-net by 3.68%, SegNet by 14.45%, and FCN-8 by 2.34%, in terms of DICE score using the same dataset.

The burden of OA-health services and economics

Osteoarthritis (OA) is a highly prevalent and disabling condition that affects over 7% of people globally (528 million people). Prevalence levels are even higher in countries with established market economies, which have older demographic profiles and a higher prevalence of obesity, such as the US (14%). As the 15th highest cause of years lived with disability (YLDs) worldwide, the burden OA poses to individuals is substantial, characterized by pain, activity limitations, and reduced quality of life. The economic impact of OA, which includes direct and indirect (time) costs, is also substantial, ranging from 1 to 2.5% of gross national product (GNP) in countries with established market economies. In regions around the world, the average annual cost of OA for an individual is estimated between $700-$15,600 (2019 USD). Though trends in OA prevalence vary by geography, the prevalence of OA is projected to rise in regions with established market economies such as North America and Europe, where populations are aging and the prevalence of obesity is rising.

A Cross-Sectional Study of Association between Plasma Selenium Levels and the Prevalence of Osteoarthritis: Data from the Xiangya Osteoarthritis Study

OBJECTIVES

Selenium plays an indispensable role in antioxidant and antiinflammation processes. Oxidative stress and inflammation have been hypothesized to be involved in the pathogenesis of cartilage degeneration. We sought to examine the association between plasma selenium levels and the prevalence of radiographic osteoarthritis (ROA).

DESIGN

A population-based cross-sectional study.

SETTING AND PARTICIPANTS

Individuals aged ≥ 50 years were retrieved from the Xiangya Osteoarthritis (XO) Study, a community-based study conducted among the residents of the rural areas of China.

METHODS

Plasma selenium concentration was measured by inductively coupled plasma-dynamic reaction cell-mass spectrometry. ROA was defined as Kellgren/Lawrence score ≥ 2 in at least one knee, hip or hand joint. The association between plasma selenium levels and ROA was evaluated by applying logistic and spline regression.

RESULTS

A total of 1,032 subjects (women: 52.5%; mean age: 63.1 years; ROA prevalence: 45.4%) were included. Compared with the highest tertile, the odds ratios (ORs) for ROA were 1.24 (95% confidence interval [CI]: 0.91 to 1.68) and 1.77 (95% CI: 1.31 to 2.40) in the middle and lowest tertile of plasma selenium, respectively (P for trend<0.05). The results were not changed materially with adjustment of potential confounders. In addition, subjects who had lower plasma selenium levels exhibited a higher prevalence of ROA in a dose-response relationship manner (P=0.005).

CONCLUSION

This study suggests that subjects with lower levels of plasma selenium exhibited a higher prevalence of ROA in a dose-response relationship manner. However, additional studies are still needed to verify the potential causal relationship.

Knee extensor muscle weakness is a risk factor for the development of knee osteoarthritis: an updated systematic review and meta-analysis including 46 819 men and women

OBJECTIVE

To update a systematic review on the association between knee extensor muscle weakness and the risk of incident knee osteoarthritis in women and men.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Systematic searches in PubMed, EMBASE, SPORTDiscus, CINAHL, AMED and CENTRAL in May 2021.

ELIGIBLE CRITERIA FOR SELECTING STUDIES

Longitudinal studies with at least 2 years follow-up including baseline measure of knee extensor muscle strength, and follow-up measure of symptomatic or radiographic knee osteoarthritis. Studies including participants with known knee osteoarthritis at baseline were excluded. Risk of bias assessment was conducted using six criteria for study validity and bias. Grading of Recommendations Assessments, Development and Evaluation assessed overall quality of evidence. Meta-analysis estimated the OR for the association between knee extensor muscle weakness and incident knee osteoarthritis.

RESULTS

We included 11 studies with 46 819 participants. Low quality evidence indicated that knee extensor muscle weakness increased the odds of symptomatic knee osteoarthritis in women (OR 1.85, 95% CI 1.29 to 2.64) and in adult men (OR 1.43, 95% CI 1.14 to 1.78), and for radiographic knee osteoarthritis in women: OR 1.43 (95% CI 1.19 to 1.71) and in men: OR 1.39 (95% CI 1.07 to 1.82). No associations were identified for knee injured populations except for radiographic osteoarthritis in men.

DISCUSSION

There is low quality evidence that knee extensor muscle weakness is associated with incident symptomatic and radiographic knee osteoarthritis in women and men. Optimising knee extensor muscle strength may help to prevent knee osteoarthritis.

PROSPERO REGISTRATION NUMBER

CRD42020214976.

Osteoarthritis: A Review of Novel Treatments and Drug Targets

Osteoarthritis affects over 10% of our population over the age of 60 years old, significantly reducing their quality of life and increasing morbidity. A number of aetiological factors contribute to the development of osteoarthritis including obesity, genetic factors, injury and increasing age. Many of the pathological processes which underlie the condition remain poorly understood and therefore limited progress has been made in developing effective disease modifying treatments. This review article aims to summarise our current understanding of osteoarthritis, the molecular mechanisms which drive the disease and current progress in developing therapeutic strategies to target these. 

Effect of a PA-led arthritis center on hip and knee osteoarthritis care

OBJECTIVE

To evaluate the effect of an arthritis center on patient care and operational throughput.

METHODS

A single-institution, retrospective review was conducted of patients with hip or knee osteoarthritis from January 2016 to October 2019. Our physician assistant (PA) led arthritis center opened in November 2017, and manages nonoperative treatment of osteoarthritis by formulating individualized treatment plans. Descriptive and inferential statistics comparing operational measures, treatment patterns, and patient satisfaction pre- and postcenter opening were performed.

RESULTS

Overall patient volume, new patient volume, and the proportion of new patients seen increased after the arthritis center opened. Encounters per patient and clinicians seen per patient decreased, while the rate of injections and surgery increased. Patient satisfaction improved after opening of the arthritis center.

CONCLUSIONS

The establishment of a dedicated PA-led arthritis center is associated with improved access to care, operational efficiency, and patient satisfaction in patients with hip and knee osteoarthritis.

Predicting postoperative transfusion in elective total HIP and knee arthroplasty: Comparison of different machine learning models of a case-control study

BACKGROUND

Total joint arthroplasty (TJA) is a very successful orthopedics procedure but associates with a significantly high transfusion rate.

OBJECTIVE

In this study, we aimed to determine predictors of postoperative blood transfusion in patients undergoing elective hip and knee TJA patients and compare the accuracy of machine learning (ML) algorithms in predicting transfusion risk.

METHODS

We utilized data from 12,642 patients undergoing primary unilateral TJA. Risk factors and demographic information were extracted, and predictive models were developed using seven ML algorithms. The area under the receiver operating characteristic curve was used to measure the predictive accuracy of each algorithm.

RESULTS

The overall transfusion rate was 18.7%. Patient-related risk factors for transfusion included age 65-85 (Odds Ratio (OR): 1.175-1.222), female (OR: 1.246), American Society of Anesthesiologists grade Ⅱ or greater (OR: 1.264-2.758). Surgical factors included operation time (OR: 1.736), drain use (OR: 2.202) as well as intraoperative blood loss (OR: 7.895). Elevated preoperative Hb (OR: 0.615), Hct (OR: 0.800), BMI (≥24 kg/m2) (OR: 0.613-0.731) and tranexamic acid use (OR: 0.375) were associated with decreased risk of postoperative transfusion. The long short-term memory networks (LSTM) and random forest (RF) models achieved the highest predictive accuracy (p < 0.001).

CONCLUSION

The risk factors identified in the current study can provide specific, personalized postoperative transfusion risk assessment for a patient considering lower limb TJA. Furthermore, the predictive accuracies of LSTM and RF algorithms were significantly higher than the others, making them potential tools for future personalized preoperative prediction of risk for postoperative transfusion.

The Effect of Body Mass Index and Metformin on Matrix Gene Expression in Arthritic Primary Human Chondrocytes

OBJECTIVE

Obesity is a known risk factor for knee osteoarthritis (OA). Diabetes has been associated with progression of OA and metformin is the first-line treatment in type 2 diabetes. The effect of the body mass index (BMI) and metformin on the expression of certain matrix genes in human chondrocytes is unclear. The purpose of this study was to investigate the effect of BMI and metformin on the expression of matrix genes in primary human chondrocytes.

DESIGN

Adult female patients undergoing knee arthroplasty for end-stage OA were enrolled. Primary chondrocytes were cultivated and stimulated with metformin. Matrix gene expression was analyzed using polymerase chain reaction. Clinical data were used in multivariable regression models to assess the influence of BMI and metformin stimulation on gene expression.

RESULTS

A total of 14 patients were analyzed. BMI was a predictor of increased expression in ADAMTS5 (β = -0.11, P = 0.03). Metformin slightly reduced expression in ADAMTS5 (β = 0.34, P = 0.04), HIF-1a (β = 0.39, P = 0.04), IL4 (β = 0.30, P = 0.02), MMP1 (β = 0.47, P < 0.01), and SOX9 (β = 0.37, P = 0.03). The hip-knee-ankle angle and proton pump inhibitors (PPIs) intake were associated with reduced SOX9 expression (β = 0.23, P < 0.01; β = 2.39, P < 0.01). Higher C-reactive protein (CRP) levels were associated with increased MMP1 expression (β = -0.16, P = 0.02).

CONCLUSION

We found that BMI exerts a destructive effect via induction of ADAMTS5. Metformin reduced the expression of catabolic genes ADAMTS5 and MMP1 and might play a role in disease prevention. Limb malalignment and PPI intake was associated with a reduced expression of SOX9, and higher CRP levels correlated with increased MMP1 expression, indicating a destructive process.

Increased serum AXL is associated with radiographic knee osteoarthritis severity

Objective

To investigate the expression and clinical significance of serum soluble AXL in patients with radiographic knee osteoarthritis (KOA).

Methods

There were 183 patients with KOA who were selected and divided based on the Kellgren‐Lawrence (KL) score into KL 0 subgroups (n = 42), KL I‐II subgroups (n = 90), and KL III‐IV subgroups (n = 51). Healthy volunteers (n = 170) in our hospital were selected with matched age and gender as the control group. AXL level in serum was detected by enzyme‐linked immunosorbent assay. The correlation between serum AXL with severity and clinical indicators of osteoarthritis was analyzed.

Results

The level of serum AXL was significantly higher in the osteoarthritis group than that in the control group (P < .05). In the osteoarthritis patients, serum AXL level was increased with the increase of KL score. Serum AXL level was positively correlated with age, body mass index, erythrocyte sedimentation rate, serum C‐reactive protein, cartilage oligomeric protein, matrix metalloproteinase‐13, and transforming growth factor‐β1 levels. The cut‐off value for serum AXL was determined as 33.375 ng/mL by receiver operating curve analysis.

Conclusion

The level of serum AXL in patients with osteoarthritis is significantly higher than in healthy controls, and is closely related to the severity of radiographic osteoarthritis.

A harm reduction model to assess the impact of new treatments for pain over standard of care among patients with osteoarthritis

BACKGROUND: Osteoarthritis (OA) affects millions of adults in the United States and can result in substantial pain, functional impairment, and significant clinical and economic burden. To manage chronic pain associated with OA, treatment guidelines recommend a variety of pharmacologic treatments, including traditional oral nonsteroidal anti-inflammatory drugs (NSAIDs), cyclooxygenase-2 inhibitors (COX-2s), and opioids. While these drug treatments can be effective at pain management, they are also associated with significant clinical and economic burden. New treatments for chronic pain among patients with OA of the hip and/or knee have the potential to reduce the occurrence of such negative clinical outcomes, including cardiovascular events, renal events, and opioid use disorder (OUD), thereby reducing health care resource use (HRU) and medical costs. OBJECTIVE: To develop a harm reduction model (HRM) to assess potential reductions of negative clinical outcomes, HRU, and medical costs associated with the use of new treatments in place of oral NSAIDs, tramadol, and non-tramadol opioids among patients with OA of the hip and/or knee in the United States. METHODS: The HRM model integrated findings from the literature and inputs from a variety of sources, along with assumptions regarding potential ability of new treatments to replace existing treatments and market penetration into a unified framework to estimate outcomes and costs. The model outputs included estimated per-patient and population-level reductions in negative clinical outcomes associated with prescribing new treatments in place of oral NSAIDs or opioids along with number needed to treat (NNT) associated with new treatments. The model assumed that new treatments will primarily be used in place of non-tramadol opioids, but more modest adoption in place of oral NSAIDs and tramadol. RESULTS: Among patients with OA of the hip and/or knee who were prescribed oral NSAIDs, tramadol, or non-tramadol opioids for chronic use (≥ 90 days), the HRM estimated total cost savings of $3.8 billion, $5.1 billion, and $29.9 billion, respectively, from prescribing new treatments for OA pain over a 36-month period. The reduced economic burden was driven by significant reductions in the incidence of negative clinical outcomes. Estimates of the NNT to avoid a negative clinical event related to NSAID and opioid treatment initiation were low for most outcomes. Estimates of NNT associated with NSAID use ranged from 4 to 17 patients, depending on outcome, and estimates of NNT associated with opioid use was 35 non-tramadol and 134 tramadol patients for OUD and ranged from 6 to 21 patients for the other clinical outcomes, depending on treatment and outcome. CONCLUSIONS: Results from the HRM suggest that prescribing new treatments in place of oral NSAIDs and/or opioids for OA pain results in a potentially substantial reduction in patients experiencing negative clinical outcomes and reductions in all-cause HRU and costs. DISCLOSURES: This study was sponsored by Pfizer and Eli Lilly and Company. Silverman was a paid consultant to Pfizer and Eli Lilly and Company in connection with this study. Beck and Schepman are employees of Pfizer with stock and/or stock options. Robinson is an employee and minor stockholder of Eli Lilly and Company. Rice, White, and Fernan are employees of the Analysis Group, who were paid consultants to Pfizer and Eli Lilly and Company for this study and development of the manuscript.

An Automatic Knee Osteoarthritis Diagnosis Method Based on Deep Learning: Data from the Osteoarthritis Initiative

Osteoarthritis (OA) is the most common form of arthritis. According to the evidence presented on both sides of the knee bones, radiologists assess the severity of OA based on the Kellgren–Lawrence (KL) grading system. Recently, computer-aided methods are proposed to improve the efficiency of OA diagnosis. However, the human interventions required by previous semiautomatic segmentation methods limit the application on large-scale datasets. Moreover, well-known CNN architectures applied to the OA severity assessment do not explore the relations between different local regions. In this work, by integrating the object detection model, YOLO, with the visual transformer into the diagnosis procedure, we reduce human intervention and provide an end-to-end approach to automatic osteoarthritis diagnosis. Our approach correctly segments 95.57% of data at the expense of training on 200 annotated images on a large dataset that contains more than 4500 samples. Furthermore, our classification result improves the accuracy by 2.5% compared to the traditional CNN architectures.

Daily Walking and the Risk of Knee Replacement Over 5 Years Among Adults With Advanced Knee Osteoarthritis in the United States

OBJECTIVE

To examine the association of the volume and intensity of daily walking at baseline with the risk of knee replacement (KR) over 5 years in adults with advanced structural knee osteoarthritis.

DESIGN

Prospective, longitudinal, and multicenter observational study.

SETTING

Osteoarthritis Initiative study with follow-up from 2008-2015.

PARTICIPANTS

Community-dwelling adults with or at risk of knee osteoarthritis were recruited from 4 sites in the United States (N=516; mean age, 67.7±8.6y; body mass index, 29.3±4.7 kg/m2; 52% female). We included participants with advanced structural disease, without KR and had valid daily walking data (quantified using Actigraph GT1M), at baseline.

INTERVENTIONS

Not applicable.

MAIN OUTCOMES

KR. Walking volume was measured as steps/day and intensity as minutes/day spent not walking (0 steps/min) and walking at very light (1-49 steps/min), light (50-100 steps/min), or moderate (>100 steps/min) intensities. To examine the relationship of walking volume and intensity with the risk of KR, we calculated hazard ratios (HRs) and 95% confidence intervals (CIs) adjusting for covariates.

RESULTS

Of 516 adults with advanced structural disease, 88 received a KR over 5 years (17%). Walking an additional 1000 steps/d was not associated with the risk of KR (adjusted HR=0.95; 95% CI, 0.84-1.04). Statistically, replacing 10 min/d of very light and light walking with 10 min/d of moderate walking reduced the risk of KR incidence by 35% and 37%, respectively (adjusted HR=0.65, 95% CI, 0.45-0.94, for very light and adjusted HR=0.63; 95% CI, 0.40-1.00, for light).

CONCLUSIONS

Daily walking volume and intensity did not increase KR risk over 5 years and may be protective in some cases in adults with advanced structural knee osteoarthritis.

Expression and related mechanisms of miR-330-3p and S100B in an animal model of cartilage injury

Objective

To investigate the roles of and relationship between microRNA (miR)-330-3p and S100 calcium-binding protein B (S100B) in an animal model of cartilage injury.

Methods

This study included 30 New Zealand male rabbits randomly divided into three groups: an intervention group, a model group and a sham surgery control group. Modelling was performed in the intervention and model groups, but in the sham surgery group, only the skin was cut. After modelling, the intervention and model groups were injected with the miR-330-3p overexpression vector GV268-miR-330-3p or the control GV268-N-ODN vector, respectively, twice a week for 7 weeks.

Results

Levels of interleukin-1β and tumour necrosis factor-α in the synovial fluid were significantly higher in the model group than in the intervention and control groups. The level of miR-330-3p in the cartilage tissue was significantly higher in the control group than in the model group but it was significantly lower compared with the intervention group. Levels of S100B, fibroblast growth factor receptor 1 and fibroblast growth factor-2 in the cartilage tissue of rabbits in the model group were significantly higher compared with the control and intervention groups.

Conclusion

These findings demonstrate that the upregulation of miR-330-3p can inhibit the expression of S100B.

Long-Term Outcome Measures of Repeated Non-Animal Stabilized Hyaluronic Acid (Durolane) Injections in Osteoarthritis: A 6-Year Cohort Study with 623 Consecutive Patients

Purpose

To determine the duration of symptom relief following repeated administration of hyaluronic acid injections for osteoarthritis.

Patients and Methods

This was a 6-year observational study with 623 consecutive patients who had received hyaluronic acid injections. The primary outcome measure was the mean time between injections measured in days. Classical one-sample 2-sided t-tests, one-way analysis of variances and post-hoc analyses were performed to determine if there were statistically significant differences between age, gender, radiographic severity and the type of joints injected. All patients were invited to complete an online post-treatment experience and satisfaction survey.

Results

The analysis included 727 joints (mean Kellgren-Lawrence grade, 2.9 ± 0.8 (range 2–4)) in 623 patients (297 (47.7%) male; mean age at first injection, 57.8 ± 12.7 years (range 21.2–92.1)). Patients ranged from having 1–8 injections per joint. The mean time between injections in days was 466.8 ± 321.7 (2nd injection, 157 joints), 400.5 ± 164.7 (3rd injection, 58 joints), 378.2 ± 223.1 (4th injection, 27 joints), 405.3 ± 216.3 (5th injection, 7 joints), 268.4 ± 104.4 (6th injection, 5 joints), 289.8 ± 99.4 (7th injection, 4 joints), and 272.5 ± 33.2 (8th injection, 2 joints). Patients with grades 2 and 3 compared to grade 4 osteoarthritis experienced a longer time between injections (F (2, 154) = 3.53, p = 0.0316). No statistically significant differences were observed between age, gender, or joint groups. The survey included 233 participants (109 (46.8% male)). A total of 144 respondents (64.9%) recommended hyaluronic acid injections for osteoarthritis.

Conclusion

Pain relief from hyaluronic acid injections was sustained for on average 466.8 days post initial treatment. Patients who received subsequent 3rd, 4th, and 5th injections also experienced extended duration of benefit. Patients with grades 2 or 3 osteoarthritis are more likely to experience a longer duration of relief.

Race Differences in Post-Acute Physical Therapy Utilization and Patient-Reported Function after Total Knee Arthroplasty

OBJECTIVE

This observational cohort study included patients of Black and White race and non-Hispanic ethnicity with end-stage knee osteoarthritis who were scheduled to receive total knee arthroplasty (TKA) surgery. We examined whether there are race differences in (1) use of physical therapy (PT) across all post-acute settings and (2) patient-reported physical function following TKA.

METHODS

We collected pre- and post-operative physical function data and post-operative rehabilitation data on 104 Black and White individuals undergoing TKA. Regression analyses and independent samples t-tests were used to explore the predictive value of race on post-operative functional outcome and compare PT utilization within each post-acute setting and across all post-acute rehabilitation settings.

RESULTS

Total PT received was similar between White and Black participants, but there were significant race differences in PT utilization within specific settings. Race did not significantly predict function after TKA, but Black participants had slightly lower self-reported function both before and after surgery than White participants.

CONCLUSION

This is the first study to examine both PT utilization and functional outcomes in a sample of individuals undergoing TKA, and results indicate differences in where post-operative PT is received between Black and White patients.

Stem Cell Therapy and Its Significance in Pain Management

Pain management has always been a challenging issue, which is why it has been a major focus of many rigorous studies. Chronic pain which typically lasts for more than three months is prevalent at an astounding rate of 11% to 19% of the adult population. Pain management techniques have gone through major advances in the last decade with no major improvement in the quality of life in affected populations. Recently there has been growing interest in the utilization of stem cells for pain management. Advancement of stem cell therapy has been noted for the past few years and is now being used in human clinical trials. Stem cell therapy has shown promising results in the management of neuropathic, discogenic back, osteoarthritis, and musculoskeletal pain. In this article, we will discuss the role of stem cells in the pain management of the aforementioned conditions, along with the mechanism, adverse effects, and risks of stem cell therapy.

Pain perception in chronic knee osteoarthritis with varying levels of pain inhibitory control: an exploratory study

Background and aims Pain is a disabling symptom in knee osteoarthritis (KOA) and its underlying mechanism remains poorly understood. Dysfunction of descending pain modulatory pathways and reduced pain inhibition enhance pain facilitation in many chronic pain syndromes but do not fully explain pain levels in chronic musculoskeletal conditions. The objective of this study is to explore the association of clinical variables with pain intensity perception in KOA individuals with varying levels of Conditioned Pain Modulation (CPM) response. Methods This is a cross-sectional, exploratory analysis using baseline data of a randomized clinical trial investigating the effects of a non-invasive brain stimulation treatment on the perception of pain and functional limitations due to KOA. Sixty-three subjects with KOA were included in this study. Data on pain perception, mood perception, self-reported depression, physical function, quality of life, and quantitative sensory testing was collected. Multiple linear regression analysis was performed to explore the association between the clinical variables with pain perception for individuals with different levels of CPM response. Results For KOA patients with limited CPM response, perception of limitations at work/other activities due to emotional problems and stress scores were statistically significantly associated with pain scores, F(2, 37) = 7.02, p < 0.01. R-squared = 0.275. For KOA patients with normal CPM response, general health perception scores were statistically significantly associated with pain scores, F(1, 21) = 5.60, p < 0.05. R-squared = 0.2104. Limitations of this study include methodology details, small sample size and study design characteristics. Conclusions Pain intensity perception is associated differently with clinical variables according to the individual CPM response. Mechanistic models to explain pain perception in these two subgroups of KOA subjects are discussed.

A Systematic Review of Current Clinical Practice Guidelines on Intra-articular Hyaluronic Acid, Corticosteroid, and Platelet-Rich Plasma Injection for Knee Osteoarthritis: An International Perspective

Background:

There are many clinical practice guidelines (CPGs) for the prevention, diagnosis, and treatment of knee osteoarthritis (OA). They differ by region, considering local health care systems, along with cultural and economic factors. Currently, there are conflicting CPG recommendations across the various publications, which makes it difficult for clinicians to fully understand the optimal treatment decisions for knee OA management.

Purpose:

To summarize the current published CPG recommendations for the role of injections in the nonoperative management of knee OA, specifically with the use of intra-articular hyaluronic acid (IA-HA), intra-articular corticosteroids (IA-CS), and platelet-rich plasma (PRP).

Study Design:

Systematic review.

Methods:

A comprehensive search identified all nonoperative knee OA CPGs within the ECRI (formerly Emergency Care Research Institute) Guidelines Trust database, the Guidelines International Network database, Google Scholar, and the Trip (formerly Turning Research Into Practice) database. Guideline recommendations were categorized into strong, conditional, or uncertain recommendations for or against the use of IA-HA, IA-CS, or PRP. Guideline recommendations were summarized and depicted graphically to identify trends in recommendations over time.

Results:

The search strategy identified 27 CPGs that provided recommendations. There were 20 recommendations in favor of IA-HA use, 21 recommendations in favor of IA-CS use, and 9 recommendations that were uncertain or unable to make a formal recommendation for or against PRP use based on current evidence. Most recommendations considered IA-HA and IA-CS use for symptom relief when other nonoperative options are ineffective. IA-CS were noted to provide fast and short-acting symptom relief for acute episodes of disease exacerbation, while IA-HA may demonstrate a relatively delayed but prolonged effect in comparison. The CPGs concluded that PRP recommendations currently lack evidence to definitively recommend for or against use.

Conclusion:

Available CPGs provide recommendations on injectables for knee OA treatment. General guidance from a global perspective concluded that IA-CS and IA-HA are favored for different needed responses and can be utilized within the knee OA treatment paradigm, while PRP currently has insufficient evidence to make a conclusive recommendation for or against its use.

The Effect of Local Heat Therapy versus Cold Rub Gel on Pain and Joint Functions in Patients with Knee Osteoarthritis

This study was compared the effect of local heat therapy versus cold rub gel on pain and joint function in patients with knee osteoarthritis. One hundred seventeen patients with knee osteoarthritis were randomly assigned to cold rub gel, local heat therapy, and control group. Data were collected by knee injury and osteoarthritis outcome score at a week prior to the interventions and on weeks of 1, 2, 3, and 4 of the interventions. A significant difference was found between the three groups in terms of pain severity (p = .001), joint symptoms (p = .001), ADL function (p = .001), Sport and Recreation function (p = .001), except Knee related QOL (p = .3). Cold rub gel and heat therapy were both effective in improving pain and joint function in patients with knee osteoarthritis.

A Comprehensive Review of Viscosupplementation in Osteoarthritis of the Knee

PURPOSE OF REVIEW

The purpose of this systematic review is to discuss emerging evidence in the field of viscosupplementation for chronic knee pain secondary to Osteoarthritis (OA). This review focuses on types of viscosupplementation that are clinically available currently, evidence to support their use, contraindications, and adverse events.

RECENT FINDINGS

OA, also known as degenerative joint disease, is the most common form of arthritis in the United States, affecting 54.4 million, or 22.7% of the adult population. The knee is the most common joint affected in OA, with up to 41% involvement, 30% in the hands, and 19% in the hips. The pathophysiology of OA is complex, with contributing factors including mechanical stress to the joint, as well as many person-specific factors such as genetic susceptibility, ethnicity, nutrition, and sex. Treatment modalities include weight control, exercise, non-steroidal and steroidal anti-inflammatory drugs, opioids, intra-articular platelet-rich plasma, placebo, corticosteroid injection, intra-articular viscosupplementation, and surgery. Viscosupplementation consists of injection of hyaluronic acid (HA) into affected joints, intending to restore the physiologic viscoelasticity in the synovial fluid (SF) in the absence of inflammation. HA has also been shown to downregulate pro-inflammatory factors, such as PGE2 and NFkB, and proteases and proteinases known to break down the joint matrix.The contraindications for HA injection are similar to any other injection therapy, and adverse events are usually mild, local, and transient. Viscosupplementation (VS) is effective over placebo and more effective than NSAIDs and corticosteroids in pain reduction and improved functionality; however, guidelines recommend neither for nor against its use, demonstrating variability in the existing evidence base.Current VS options divide primarily into native vs. cross-linked and low-molecular-weight vs. high-molecular-weight. Current treatment options include Hylan g-f-20, Sodium Hyaluronate preparations (Suparts Fx, Euflexxa, Gelsyn-3, Durolane, Hyalgen), single-use agents (Gel-One, Synvisc-One, Monovisc), and Hyaluronan (Orthovisc, Monovisc, Hymovic). They share a common safety profile, and all have evidence supporting their efficacy. Their specific details are reviewed here.

SUMMARY

OA is the most common form of arthritis. It is a chronic, debilitating illness with a high impact on the functionality and quality of life of a significant part of the population in the western world. Treatments include medical management, physical therapy, activity modification, injection, and surgery. VS effectively reduces pain, increases functionality, and delays surgery in the knee to treat osteoarthritis. While previous studies have demonstrated variable results, more evidence is becoming available generally supportive of the benefit of VS in the treatment of knee OA.

Joint Corticosteroid Injection Associated With Higher Physical Therapy Compliance in Knee Osteoarthritis

Background Knee corticosteroid injection (KCSI) and physical therapy (PT) are two efficacious treatments for knee osteoarthritis (KOA). However, poor adherence to PT in resource-limited communities might limit its effectiveness. KCSI prior to PT might improve adherence in this population. Methodology This was a retrospective cohort analysis of patients referred to PT for KOA from January 01, 2018 to December 31, 2019 from an adult primary care resident clinic in Hartford, Connecticut, USA. Patients were divided into two groups, namely, those who had a KCSI around the time of the referral versus those who did not. PT adherence was evaluated in both groups. Results A total of 143 patients referred to PT were selected, and 11 patients were excluded. In total, 38/132 patients had a KCSI within a four-month window of the PT referral. Patients were mostly Hispanic (no injection 79.8% vs. injection 78.9%) females (80.9% vs. 71.1%), the average age was in the 60s, and over 90% were insured by either Medicaid or Medicare. In the injection group, 18/38 patients completed at least one PT visit (47.4%) versus 21/94 patients (22.3%) in the noninjection group. The odds ratio of undergoing PT was 1.38 (95% confidence interval [CI] = 1.14-1.69; p = 0.002), and the rate ratio of PT visits was 2.50 (95% CI = 1.82-3.42; p = 1.36 × 10-8), both adjusted for age, sex, and severity. Among those who attended at least one session, the mean number of PT visits was 5.4 in both injection and noninjection groups (median 5 versus 4).  Conclusions In a predominantly Hispanic patient population, those who underwent KCSI were more likely to undergo PT and, as a group, attend more sessions.

Nortriptyline for pain in knee osteoarthritis: a double-blind randomised controlled trial in New Zealand general practice

BACKGROUND

Osteoarthritis (OA) of the knee is a common cause of chronic pain. Analgesics that are currently available have limited efficacy and may be poorly tolerated. Tricyclic antidepressants are used as analgesics for other chronic conditions, but they have not been evaluated as analgesics in OA.

AIM

To investigate the analgesic efficacy of nortriptyline in people with knee OA.

DESIGN AND SETTING

A two-arm, parallel-group, 1:1, double-blind, randomised, placebo-controlled trial in Christchurch, New Zealand.

METHOD

Participants were recruited from orthopaedic outpatient clinics, primary care, and through public advertising. Adults with knee OA and a pain score of ≥20 points on the 50-point Western Ontario and McMaster University Osteoarthritis Index (WOMAC) pain subscale were randomised to receive either nortriptyline or identical placebo for 14 weeks. The primary outcome was knee pain at 14 weeks measured using the WOMAC pain subscale. Secondary outcomes included: function; stiffness; non-steroidal anti-inflammatory drug, opioid, and/or paracetamol use; each participant's global assessment; and adverse effects at 14 weeks.

RESULTS

Of the 205 randomised participants, 201 (98.0%) completed follow-up at 14 weeks. The baseline-adjusted mean WOMAC pain subscale score at week 14 was 6.2 points lower (95% confidence interval = -0.26 to 12.6, P = 0.06) in the nortriptyline arm versus the placebo arm. Differences in secondary outcomes generally favoured the nortriptyline arm, but were small and unlikely to be clinically relevant. However, the following were all more commonly reported by participants taking nortriptyline than those taking a placebo: dry mouth (86.9% versus 51.0%, respectively, P<0.001), constipation (58.6% versus 30.4%, respectively, P<0.001), and sweating (31.3% versus 20.6%, respectively, P = 0.033).

CONCLUSION

This study suggests nortriptyline does not significantly reduce pain in people with knee OA. The adverse effect profile was as expected.

Individual variation in diurnal cortisol in patients with knee osteoarthritis: Clinical correlates

BACKGROUND

The cortisol awakening response (CAR) is a core biomarker of hypothalamic-pituitary-adrenal (HPA) axis regulation. To date, however, studies of HPA-axis function among patients with chronic pain are scarce and show equivocal results. The objectives of this study were to investigate the association between CAR and pain-related outcomes and to investigate potential sex differences in patients with knee osteoarthritis (KOA).

METHODS

In this cross-sectional study, KOA patients (N = 96) completed self-report questionnaires assessing pain and psychosocial factors and underwent Quantitative Sensory Testing (QST) to assess pressure pain threshold (PPT). Additionally, salivary cortisol samples (N = 60) were collected to assess HPA-axis function at 6 time points (awakening, 15- and 30-minute post-awakening, 4 PM, 9 PM and bedtime). The CAR was calculated by examining increases in salivary cortisol from awakening to 30 min post awakening and the total post-awakening cortisol concentration by calculating the lower areas under the curve of cortisol with respect to ground (AUC_G).

RESULTS

Patients with a relatively blunted CAR had significantly higher anxiety levels and lower PPT than patients with relatively normal CAR. Similarly, patients with a relatively reduced AUC_G had significantly higher pain interference and anxiety levels compared to patients with relatively normal AUC_G. PPT was positively correlated with CAR and AUC_G and negatively correlated with pain severity and anxiety_. Men with KOA had significantly lower anxiety, higher PPT and higher CAR and AUC_G than women with KOA. Mediation analysis results revealed a significant indirect effect of PPT on the relationship between sex and AUC_G. CONCLUSIONS: The findings of this study suggest that neuroendocrine factors such as CAR and AUC_G may contribute to individual differences in pain-related outcomes in patients with KOA. Additionally, our results show sex differences in the magnitude of morning HPA activation and pain-related outcomes. Finally, our findings are suggestive of a sex-dependent relationship between post-awakening cortisol concentrations and pain perception. Future research should examine these associations across various pain populations.

Osteoarthritis care and risk of total knee arthroplasty among medicare beneficiaries

OBJECTIVE

To examine health care utilization among patients with knee osteoarthritis and test if utilization differed among residents of regions with high and low rates of total knee arthroplasty (TKA).

DESIGN

This was a retrospective cohort study of U.S. Medicare beneficiaries in 2005 - 2010 with knee osteoarthritis. Health care utilization for knee complaints, including rates of physician visits, physical therapy, knee injections and arthroscopy were abstracted from claims files until TKA or the end of study in 2015. Utilization was compared among beneficiaries who lived in regions with high or low rates of TKA.

RESULTS

Among 988,570 beneficiaries with knee osteoarthritis, 327,499 beneficiaries (33.1%) had TKA during follow-up (median 5.6 years). Higher rates of visits for knee complaints were associated with increased risks of arthroplasty, while use of physical therapy, specialist care, and intra-articular treatments were associated with lower risks. Frequency of TKA varied from 26.4% in the lowest quintile region to 42.1% in the highest quintile. Rates of physician visits, physical therapy, specialist care, and use of intra-articular injections varied inversely with arthroplasty quintile. For example, physical therapy was used by 32.5% of beneficiaries in the lowest quintile region and 23.6% in the highest quintile region. Physical therapy was associated with lower TKA rates across all quintiles.

CONCLUSIONS

Dedicated non-surgical osteoarthritis care was infrequently used by elderly Americans with knee osteoarthritis. Non-surgical care was more common in regions with low rates of TKA, suggesting reciprocal emphasis on medical versus surgical treatment across regions.

Reducing sedentary time using an innovative mHealth intervention among patients with total knee replacement: Rationale and study protocol

INTRODUCTION

Although knee replacement is effective for improving pain and physical function, subsequent improvements in physical activity typically do not follow. As a result, many patients spend most of their day engaged in sedentary behavior, which may put them at higher risk of experiencing poor function and disability. Intervening on sedentary time, rather than physical activity, may be a more feasible first-step approach for modifying activity-related behaviors in adults who received knee replacement.

OBJECTIVE

The purpose of this study is to examine the use of a mobile health (mHealth) intervention to reduce sedentary time among adults who received a knee replacement at 3 and 6 months after surgery.

METHODS

Patients (n = 92) scheduled for knee replacement will be recruited and at 4 weeks after surgery, they will be randomized to either NEAT!2 or Control. NEAT!2 participants will use the NEAT!2 smartphone app, which provides a vibration and/or audible tone to interrupt prolonged bouts of sitting detected from the smartphone's internal accelerometer, until 3 months after surgery. NEAT!2 participants will receive biweekly coaching calls between 4 and 12 weeks after surgery. Control participants will receive an education control app and receive non-intervention calls to assess general surgery recovery. Both groups will receive 3 retention calls between 3 and 6 months. Data collection will occur pre-operatively and at 3 and 6 months after surgery.

DISCUSSION

The results of this study will help to determine whether an innovative remotely-delivered, mHealth sedentary reduction intervention can decrease sedentary time in adults after knee replacement.

The Value of Total Knee Replacement in Patients With Knee Osteoarthritis and a Body Mass Index of 40 kg/m2 or Greater : A Cost-Effectiveness Analysis

BACKGROUND

Total knee replacement (TKR) is an effective and cost-effective strategy for treating end-stage knee osteoarthritis. Greater risk for complications among TKR recipients with a body mass index (BMI) of 40 kg/m2 or greater has raised concerns about the value of TKR in this population.

OBJECTIVE

To assess the value of TKR in recipients with a BMI of 40 kg/m2 or greater using a cost-effectiveness analysis.

DESIGN

Osteoarthritis Policy Model to assess long-term clinical benefits, costs, and cost-effectiveness of TKR in patients with a BMI of 40 kg/m2 or greater.

DATA SOURCES

Total knee replacement parameters from longitudinal studies and published literature, and costs from Medicare Physician Fee Schedules, the Healthcare Cost and Utilization Project, and published data.

TARGET POPULATION

Recipients of TKR with a BMI of 40 kg/m2 or greater in the United States.

TIME HORIZON

Lifetime.

PERSPECTIVE

Health care sector.

INTERVENTION

Total knee replacement.

OUTCOME MEASURES

Cost, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs), discounted at 3% annually.

RESULTS OF BASE-CASE ANALYSIS

Total knee replacement increased QALYs by 0.71 year and lifetime medical costs by $25 200 among patients aged 50 to 65 years with a BMI of 40 kg/m2 or greater, resulting in an ICER of $35 200. Total knee replacement in patients older than 65 years with a BMI of 40 kg/m2 or greater increased QALYs by 0.39 year and costs by $21 100, resulting in an ICER of $54 100.

RESULTS OF SENSITIVITY ANALYSIS

In TKR recipients with a BMI of 40 kg/m2 or greater and diabetes and cardiovascular disease, ICERs were below $75 000 per QALY. Results were most sensitive to complication rates and preoperative pain levels. In the probabilistic sensitivity analysis, at a $55 000-per-QALY willingness-to-pay threshold, TKR had a 100% and 90% likelihood of being a cost-effective strategy for patients aged 50 to 65 years and patients older than 65 years, respectively.

LIMITATION

Data are derived from several sources.

CONCLUSION

From a cost-effectiveness perspective, TKR offers good value in patients with a BMI of 40 kg/m2 or greater, including those with multiple comorbidities.

PRIMARY FUNDING SOURCE

National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health.

Real-World Health Care Resource Utilization and Costs Among US Patients with Knee Osteoarthritis Compared with Controls

PURPOSE

To determine the prevalence, healthcare resource utilization and costs (HCRU&C) of knee osteoarthritis (OA) patients versus controls.

PATIENTS AND METHODS

Retrospective, matched-cohort administrative claims analysis using IBM MarketScan databases (2011-2017). Newly diagnosed, adult (18+ yrs) knee OA patients identified by ICD9/10 code were matched 1:1 to controls by age, sex, payer, and geography; alpha level set to 0.05. Prevalence was estimated for 2017. All-cause and knee OA-related HCRU&C reported per-patient-per-year (PPPY) over follow-up period up to 4 years.

RESULTS

Overall 2017 knee OA prevalence was 4% (615,514 knee OA/15.4M adults). A total of 510,605 patients meeting inclusion criteria were matched 1:1 with controls. The knee OA cohort had mean age 60 years and was 58% female. Versus controls, knee OA patients had significantly more PPPY outpatient (84.5 versus 45.0) and pharmacy (29.8 versus 19.8) claims, and significantly higher PPPY outpatient costs ($12,571 versus $6,465), and pharmacy costs ($3,655 versus $2,038). Knee OA patients incurred $7,707 more PPPY total healthcare costs than controls, of which $4,674 (60.6%) were knee OA-related medical claims and $1,926 (25%) were knee OA-related medications of interest. PPPY costs for nonselective NSAIDs, cyclooxygenase-2 (COX-2) inhibitors, intraarticular hyaluronic acid, non-acute opioids, and knee replacement were higher for knee OA patients than controls. Using median and mean all-cause total cost ($9,330 and $24,550, respectively), the estimated sum cost of knee OA patients in MarketScan ranged from $5.7B to $15B annually.

CONCLUSION

This retrospective analysis demonstrated an annual 2017 prevalence of 4.0% (≥18 years) and 13.2% (≥65 years) for newly diagnosed knee OA patients. Compared with controls, all-cause costs were significantly higher for knee OA patients, nearly double that of matched controls, attributable to increased medical and treatment costs and comorbidity treatment burden. Additionally, the estimated annual cost of knee OA treatment was substantial, ranging between $5.7 billion and $15 billion.

Exploring Race Differences in Satisfaction with Rehabilitation Following Total Knee Arthroplasty: a Qualitative Study

BACKGROUND

The purpose of this qualitative focus group study was to explore race differences in the rehabilitation experience and satisfaction with rehabilitation following total knee arthroplasty (TKA).

METHODS

We conducted a series of qualitative focus group discussions with groups of Non-Hispanic White and Non-Hispanic Black older adults who recently underwent TKA. We used grounded theory approach, which asks the researcher to develop theory from the data that are collected. Participants discussed barriers and facilitators to accessing rehabilitation after surgery, opinions regarding their physical therapists, the amount of post-operative physical therapy received, and overall satisfaction with the post-operative rehabilitation process.

RESULTS

Thirty-six individuals participated in focus groups. Three major themes emerged: (1) Participants reported overall positive views of their post-TKA rehabilitation experience. They particularly enjoyed one-on-one care, the ability to participate in "prehabilitation", and often mentioned specific interventions they felt were most helpful in their recovery. (2) Despite this, substantial barriers to accessing physical therapy exist. These include suboptimal pain management, copayments and other out-of-pocket costs, and transportation to visits. (3) There were minor differences in the rehabilitation experiences between Black and White participants. Black participants reported longer paths toward surgery and occasional difficulty interacting with rehabilitation providers.

CONCLUSIONS

Individuals undergoing TKA can largely expect positive rehabilitation experiences post-operatively. However, some barriers to post-operative physical therapy exist and may differ between Black and White patients. Physical therapists should increase their awareness of these barriers and work to minimize them whenever possible.

Exosomes Derived from Non-Classic Sources for Treatment of Post-Traumatic Osteoarthritis and Cartilage Injury of the Knee: In Vivo Review

Osteoarthritis of the knee is one of the most common chronic, debilitating musculoskeletal conditions. Current conservative treatment modalities such as weight loss, non-steroidal anti-inflammatory drugs, and intra-articular steroid injections often only provide temporary pain relief and are unsatisfactory for long-term management. Though end stage osteoarthritis of the knee can be managed with total knee arthroplasty (TKA), finding alternative non-surgical options to delay or prevent the need for TKA are needed due to the increased healthcare costs and expenditures associated with TKA. Exosomes have been of particular interest given recent findings highlighting that stem cells may at least partially mediate some of their effects through the release of extracellular vesicles, such as exosomes. As such, better understanding the biological mechanisms and potential therapeutic effects of these exosomes is necessary. Here, we review in vivo studies that highlight the potential clinical use of exosomes derived from non-classical sources (not bone marrow or adipose derived MSCs derived MSCs) for osteoarthritis of the knee.

Estimation of Expenditure and Challenges Related to Rehabilitation After Knee Arthroplasty: A Hospital-Based Cross-Sectional Study

BACKGROUND

Expenditure for rehabilitation following knee arthroplasty for osteoarthritis- and rehabilitation-related challenges following discharge to home after surgery is not available in the Indian context.

OBJECTIVES

To estimate cost of rehabilitation and document challenges in following rehabilitation advices, from a patient perspective.

METHODS

We conducted a hospital-based cross-sectional study of patients visiting the orthopedic department at a tertiary care public-funded hospital in New Delhi and included those who recently (less than 4 months) underwent primary knee arthroplasty for osteoarthritis. A trained physiotherapist not involved in clinical care collected information on expenditures incurred after discharge from hospital, patient's ability to recall the advices given by the physician and challenges they experienced using a semi-structured questionnaire. We report median costs by category of direct and indirect cost and used linear regression to explore determinants of cost.

RESULTS

We interviewed 82 consecutive patients (mean age 60.8 years and 68% females) with median time since surgery of 28 days. More than half (52%) sought some support for physiotherapy. The median cost of rehabilitation was INR 18,395 (Interquartile-range 11,325-27,775). Direct medical cost contributed to 74% of total cost (32% fee for services, 21% medications and lab investigations, 21% assistive devices). Twenty percent higher costs were incurred among those undergoing bilateral knee surgery after adjusting for age, sex, income, and type of physiotherapy support sought. Challenges were related to recall of advices, not understanding the recovery process and pain management.

CONCLUSION

About half patients undergoing knee arthroplasty seek support for rehabilitation after discharge to home contributing to a major portion of expenses incurred during rehabilitation. Cost-effective support mechanism for home-based rehabilitation is required for improving patient rehabilitation experiences.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s43465-021-00405-6.

Healthcare Utilization and Knee Osteoarthritis Symptoms among Urban Older Malaysian

Knee osteoarthritis (OA) is a prevalent chronic disorder in the older population. While timely management is important to minimize the consequences of knee OA, information on the utilization of healthcare services among this population remains limited. Therefore, the objectives of this study were to determine the healthcare utilization and its associated factors in older persons with knee OA. Cross-sectional data from 1073 participants aged 60 years and above from the Malaysian Elders Longitudinal Research (MELoR) study were included. The utilization rate of healthcare services was quantified. Factors related to the utilization of healthcare services were determined using logistic regression analysis. Healthcare utilization among participants with knee OA was significantly higher than those without knee OA (p < 0.01). Outpatient usage was higher (p < 0.01) in comparison to inpatient and pharmacotherapy. Being married and having an income were significantly associated with seeking outpatient care (OR: 11.136, 95% CI: 1.73–52.82, p < 0.01) and pharmacotherapy (OR: 10.439, 95% CI: 1.187–91.812, p < 0.05), while females were less likely to utilize inpatient care services (OR: 0.126, 95% CI: 0.021–0.746, p < 0.05). The higher rate of healthcare utilization among older persons with knee OA indicates the increased healthcare needs of this population, who are commonly assumed to suffer from a benign disease.

Physical Function and Quality of Life and Modification of Authentic Islamic Prayer Procedure by Osteoarthritis Knee Patients in Saudi Arabia: A Cross-sectional Study

Physical activity and quality of life of older people decline as age increases and with associated chronic diseases. The quality of life of patients was assessed using generic measures in Saudi Arabian patients. The objective of this cross-sectional study was to evaluate the quality of life among Osteoarthritis knee patients who have modified their lifestyle and adapted to chair usage to offer prayers using disease-specific knee measures. A total of 107 subjects have been evaluated among Muslims with a chair usage history to offer the prayers. There is a statistically significant difference (p < 0.001) among the history of chair users to offer prayers. Function as well as quality of life has been declined over the years, that is, from 0 to 9 years of modified (chair use) prayer in Saudi Arabian Muslims.

Efficacy and safety of duloxetine for postoperative pain after total knee arthroplasty in centrally sensitized patients: study protocol for a randomized controlled trial

Background

Postoperative residual knee pain after total knee arthroplasty (TKA) is a significant factor that contributes to patient dissatisfaction. Patients with preoperative central sensitization (CS) may be more susceptible to unexplained chronic pain after TKA, and duloxetine has been reported to be effective in post-TKA pain control in patients with CS. However, there remains limited evidence to support this off-label use in routine clinical practice. Hence, we designed this randomized, placebo-controlled, triple-blind clinical trial to evaluate the effects of preoperative screening and targeted duloxetine treatment of CS on postoperative residual pain compared with the care-as-usual control group.

Methods

This randomized controlled trial includes patients with knee osteoarthritis on a waiting list for primary unilateral TKA. Patients with preoperative CS will be randomly allocated to the perioperative duloxetine treatment group (duloxetine group) or the care-as-usual control group (placebo group). Patients in the duloxetine group will receive a half-dose of preemptive duloxetine (30 mg/day) for a week before surgery and a full-dose of duloxetine (60 mg/day) for six weeks after surgery. The primary outcome is the intensity of residual pain at six months after TKA, including the visual analogue scale, 11-point numeric rating scale, the sensory dimension of the brief pain inventory, and the pain subscale of the Knee injury and Osteoarthritis Outcome Score. The secondary outcome measures will include the pain and function related outcomes. All of the patients will be followed up at one, three, and six months after surgery. All adverse events will be recorded and immediately reported to the primary investigator and ethics committee to decide if the patient needs to drop out from the trial.

Discussion

This clinical trial will convey the latest evidence of the efficacy and safety of the application of duloxetine in postoperative pain control in CS patients who are scheduled for TKA. The study results will be disseminated at national and international conferences and published in peer-reviewed journals.

Trial registration

Chinese Clinical Trial Registry (http://www.chictr.org.cn) registration number: ChiCTR2000031674. Registered 07 April 2020.

Moving toward targeting the right phenotype with the right platelet-rich plasma (PRP) formulation for knee osteoarthritis

Intra-articular injections of platelet-rich plasma (PRP) and other novel blood-derived products developed specifically for osteoarthritis (OA) can provide pain relief and potential benefits in disease progression. Meta-analyses show the clinical superiority of PRP compared with other intra-articular injections, but results are modest and the effect sizes are small. PRP injections in knee OA are performed indiscriminately, but the clinical response varies enormously between patients because of an array of mixed OA phenotypes. Subgroup analyses are scarce; some studies stratify patients according to radiographic severity and found better results in early OA, without consensus for more advanced stages of the condition. Parallel identification of soluble and imaging biomarkers is essential to personalise and leverage PRP therapies. The inflammatory phenotype is most interesting from the PRP perspective because PRPs modulate inflammation by releasing a large pool of chemokines and cytokines, which interact with synovial fibroblasts and macrophages; in addition, they can modulate the innate immune response. No soluble biomarkers have been discovered that have implications for OA research and PRP interventions. Clinical examination of patients based on their inflammatory phenotype and imaging identification of pain sources and structural alterations could help discern who will respond to PRP. Synovial inflammation and bone marrow lesions are sources of pain, and intra-articular injections of PRP combined with subchondral bone injection can enhance clinical outcomes. Further refining ultrasound phenotypes may aid in personalising PRP therapies. Intra-articular delivery combined with injections in altered ligamentous structures, medial and coronal ligaments or premeniscal pes anserinus showed positive clinical outcomes. Although the evidence supporting these approaches are weak, they merit further consideration to refine PRP protocols and target the right OA phenotypes.

Delay to TKA and Costs Associated with Knee Osteoarthritis Care Using Intra-Articular Hyaluronic Acid: Analysis of an Administrative Database

Background

Total knee arthroplasty (TKA) is a surgical treatment for patients with knee osteoarthritis (KOA) that no longer experience symptom relief from non-operative or pharmacologic treatments. Non-operative KOA management aims to address patient symptoms and improve function, as well as forestall or mitigate the large costs associated with TKA. The primary objective of this study was to examine the relationship between intra-articular hyaluronic acid (IA-HA) treatment and delaying TKA in patients with KOA compared to patients not receiving IA-HA, as well as to identify differences in KOA-related costs incurred among patients who received or did not receive IA-HA.

Methods

This was a retrospective analysis of an administrative claims database from October 1st, 2010 through September 30th, 2015. Kaplan-Meier survival analysis was conducted to determine the TKA-free survival of patients who received IA-HA, stratified by the number of injection courses received versus those who did not receive any IA-HA. Median KOA-related costs per year were calculated for 2 comparisons: (1) patients who received IA-HA versus patients who did not receive IA-HA, among patients who eventually had TKA, and (2) patients who received IA-HA versus patients who did not receive IA-HA, among patients who did not have TKA.

Results

A total of 744 734 patients were included in the analysis. A delay to TKA was observed after IA-HA treatment for patients treated with IA-HA compared to those who did not receive IA-HA. At 1 year, the TKA-free survival was 85.8% (95% CI: 85.6%-86.0%) for patients who received IA-HA and 74.1% (95% CI: 74.0%-74.3%) for those who did not receive IA-HA. At 2 years, the TKA free survival was 70.8% (70.5%-71.1%) and 63.7% (63.5%-63.9%) in the 2 groups, respectively. Patients treated with multiple courses of IA-HA demonstrated an incremental increase in delay to TKA with more courses of IA-HA, suggesting that the risk of TKA over the study time period is reduced with additional IA-HA courses. The hazard ratio for the need of TKA was 0.85 (95% CI 0.84-0.86) for a single course and 0.27 (95% CI 0.25-0.28) for ⩾5 courses, both compared to the no IA-HA group. In patients that eventually had TKA, the median KOA-related costs were lower among those who received IA-HA before their TKA ($860.24, 95% CI: 446.65-1722.20), compared to those who did not receive IA-HA ($2659.49, 95% CI: 891.04-7480.38). For patients who did not have TKA, the median and interquartile range (IQR) KOA-related costs per year were similar for patients who received IA-HA compared with those who did not.

Conclusion

These results demonstrate that within a large cohort of KOA patients, individuals who received multiple courses of IA-HA had a progressively greater delay to TKA compared to patients who did not receive IA-HA treatment. Also, for patients who progressed to TKA, IA-HA treatment was associated with a large reduction in KOA-related healthcare costs. Based on these results, multiple, repeat courses of IA-HA may be beneficial in substantially delaying TKA in KOA patients, as well as minimizing KOA-related healthcare costs.

Risk factors for progression to total knee arthroplasty within two years of presentation for knee osteoarthritis

INTRODUCTION

Knee osteoarthritis (OA) is a leading cause of disability and functional limitations in aging adults. Total knee arthroplasty (TKA) is the gold standard treatment of this condition. The purpose of this study is to evaluate which patient characteristics are associated with proceeding to TKA.

METHODS

Retrospective review of patients with knee osteoarthritis at a single institution was conducted. Demographic, radiographic and clinical patient characteristics were analyzed. The primary outcome measure was whether patients underwent TKA over the study time-period. Univariate comparisons between patients not undergoing surgery and those undergoing TKA were performed. Multivariate logistic regression was performed to evaluate risk factors for undergoing TKA.

RESULTS

Two hundred seven patients were included in the study. One hundred eighty seven patients (90.3%) did not undergo surgery, while 20 (9.7%) underwent TKA. No statistically significant differences in demographics were observed between patients who underwent TKA and those who did not. On multivariate analysis, patients with Kellgren Lawrence grade 4 OA (OR: 20.793, p = 0.009) and varus alignment (OR: 13.044, p = 0.040) were at significantly increased risk of undergoing TKA. Using only these two variables, the area under the curve for predicting which patients would undergo TKA was 0.846, indicating excellent discrimination.

CONCLUSION

In patients diagnosed with knee OA, Kellgren Lawrence grade 4 classification and varus knee alignment are significant risk factors for undergoing TKA, and are associated with a decreased time from initial presentation to surgery. These findings may be used to counsel patients, aid triage decisions, and inform the development of future predictive models.

Diagnosis and Treatment of Hip and Knee Osteoarthritis: A Review

Importance

Osteoarthritis (OA) is the most common joint disease, affecting an estimated more than 240 million people worldwide, including an estimated more than 32 million in the US. Osteoarthritis is the most frequent reason for activity limitation in adults. This Review focuses on hip and knee OA.

Observations

Osteoarthritis can involve almost any joint but typically affects the hands, knees, hips, and feet. It is characterized by pathologic changes in cartilage, bone, synovium, ligament, muscle, and periarticular fat, leading to joint dysfunction, pain, stiffness, functional limitation, and loss of valued activities, such as walking for exercise and dancing. Risk factors include age (33% of individuals older than 75 years have symptomatic and radiographic knee OA), female sex, obesity, genetics, and major joint injury. Persons with OA have more comorbidities and are more sedentary than those without OA. The reduced physical activity leads to a 20% higher age-adjusted mortality. Several physical examination findings are useful diagnostically, including bony enlargement in knee OA and pain elicited with internal hip rotation in hip OA. Radiographic indicators include marginal osteophytes and joint space narrowing. The cornerstones of OA management include exercises, weight loss if appropriate, and education-complemented by topical or oral nonsteroidal anti-inflammatory drugs (NSAIDs) in those without contraindications. Intra-articular steroid injections provide short-term pain relief and duloxetine has demonstrated efficacy. Opiates should be avoided. Clinical trials have shown promising results for compounds that arrest structural progression (eg, cathepsin K inhibitors, Wnt inhibitors, anabolic growth factors) or reduce OA pain (eg, nerve growth factor inhibitors). Persons with advanced symptoms and structural damage are candidates for total joint replacement. Racial and ethnic disparities persist in the use and outcomes of joint replacement.

Conclusions and Relevance

Hip and knee OA are highly prevalent and disabling. Education, exercise and weight loss are cornerstones of management, complemented by NSAIDs (for patients who are candidates), corticosteroid injections, and several adjunctive medications. For persons with advanced symptoms and structural damage, total joint replacement effectively relieves pain.

Total knee replacement after high tibial osteotomy: time-to-event analysis and predictors

BACKGROUND

An important aim of high tibial osteotomy (HTO) is to prevent or delay the need for total knee replacement (TKR). We sought to estimate the frequency and timing of conversion from HTO to TKR and the factors associated with it.

METHODS

We prospectively evaluated patients with osteoarthritis (OA) of the knee who underwent medial opening wedge HTO from 2002 to 2014 and analyzed the cumulative incidence of TKR in July 2019. The presence or absence of TKR on the HTO limb was identified from the orthopedic surgery reports and knee radiographs contained in the electronic medical records for each patient at London Health Sciences Centre. We used cumulative incidence curves to evaluate the primary outcome of time to TKR. We used multivariable Cox proportional hazards analysis to assess potential preoperative predictors including radiographic disease severity, malalignment, correction size, pain, sex, age, body mass index (BMI) and year of surgery.

RESULTS

Among 556 patients who underwent 643 HTO procedures, the cumulative incidence of TKR was 5% (95% confidence interval [CI] 3%-7%) at 5 years and 21% (95% CI 17%-26%) at 10 years. With the Cox proportional hazards multivariable model, the following preoperative factors were significantly associated with an increased rate of conversion: radiographic OA severity (adjusted hazard ratio [HR] 1.96, 95% CI 1.12-3.45), pain (adjusted HR 0.85, 95% CI 0.75-0.96)], female sex (adjusted HR 1.67, 95% CI 1.08-2.58), age (adjusted HR 1.50 per 10 yr, 95% CI 1.17-1.93) and BMI (adjusted HR 1.31 per 5 kng/m2, 95% CI 1.12-1.53).

INTERPRETATION

We found that 79% of knees did not undergo TKR within 10 years after undergoing medial opening wedge HTO. The strongest predictor of conversion to TKR is greater radiographic disease at the time of HTO.

An algorithmic approach to reducing unexplained pain disparities in underserved populations

Underserved populations experience higher levels of pain. These disparities persist even after controlling for the objective severity of diseases like osteoarthritis, as graded by human physicians using medical images, raising the possibility that underserved patients' pain stems from factors external to the knee, such as stress. Here we use a deep learning approach to measure the severity of osteoarthritis, by using knee X-rays to predict patients' experienced pain. We show that this approach dramatically reduces unexplained racial disparities in pain. Relative to standard measures of severity graded by radiologists, which accounted for only 9% (95% confidence interval (CI), 3-16%) of racial disparities in pain, algorithmic predictions accounted for 43% of disparities, or 4.7× more (95% CI, 3.2-11.8×), with similar results for lower-income and less-educated patients. This suggests that much of underserved patients' pain stems from factors within the knee not reflected in standard radiographic measures of severity. We show that the algorithm's ability to reduce unexplained disparities is rooted in the racial and socioeconomic diversity of the training set. Because algorithmic severity measures better capture underserved patients' pain, and severity measures influence treatment decisions, algorithmic predictions could potentially redress disparities in access to treatments like arthroplasty.

A Systematic Review of the Incidence, Prevalence, Costs, and Activity and Work Limitations of Amputation, Osteoarthritis, Rheumatoid Arthritis, Back Pain, Multiple Sclerosis, Spinal Cord Injury, Stroke, and Traumatic Brain Injury in the United States: A 2019 Update

OBJECTIVES

To present recent evidence on the prevalence, incidence, costs, activity limitations, and work limitations of common conditions requiring rehabilitation.

DATA SOURCES

Medline (PubMed), SCOPUS, Web of Science, and the gray literature were searched for relevant articles about amputation, osteoarthritis, rheumatoid arthritis, back pain, multiple sclerosis, spinal cord injury, stroke, and traumatic brain injury.

STUDY SELECTION

Relevant articles (N=106) were included.

DATA EXTRACTION

Two investigators independently reviewed articles and selected relevant articles for inclusion. Quality grading was performed using the Methodological Evaluation of Observational Research Checklist and Newcastle-Ottawa Quality Assessment Form.

DATA SYNTHESIS

The prevalence of back pain in the past 3 months was 33.9% among community-dwelling adults, and patients with back pain contribute $365 billion in all-cause medical costs. Osteoarthritis is the next most prevalent condition (approximately 10.4%), and patients with this condition contribute $460 billion in all-cause medical costs. These 2 conditions are the most prevalent and costly (medically) of the illnesses explored in this study. Stroke follows these conditions in both prevalence (2.5%-3.7%) and medical costs ($28 billion). Other conditions may have a lower prevalence but are associated with relatively higher per capita effects.

CONCLUSIONS

Consistent with previous findings, back pain and osteoarthritis are the most prevalent conditions with high aggregate medical costs. By contrast, other conditions have a lower prevalence or cost but relatively higher per capita costs and effects on activity and work. The data are extremely heterogeneous, which makes anything beyond broad comparisons challenging. Additional information is needed to determine the relative impact of each condition.