Measuring Disease Progression in Osteoarthritis

Beyond the Surface: Nutritional Interventions Integrated with Diagnostic Imaging Tools to Target and Preserve Cartilage Integrity: A Narrative Review

This narrative review provides an overview of the various diagnostic tools used to assess cartilage health, with a focus on early detection, nutrition intervention, and management of osteoarthritis. Early detection of cartilage damage is crucial for effective patient management. Traditional diagnostic tools like radiography and conventional magnetic resonance imaging (MRI) sequences are more suited to detecting late-stage structural changes. This paper highlights advanced imaging techniques, including sodium MRI, T2 mapping, T1ρ imaging, and delayed gadolinium-enhanced MRI of cartilage, which provide valuable biochemical information about cartilage composition, particularly the glycosaminoglycan content and its potential links to nutrition-related factors influencing cartilage health. Cartilage degradation is often linked with inflammation and measurable via markers like CRP and IL-6 which, although not specific to cartilage breakdown, offer insights into the inflammation affecting cartilage. In addition to imaging techniques, biochemical markers, such as collagen breakdown products and aggrecan fragments, which reflect metabolic changes in cartilage, are discussed. Emerging tools like optical coherence tomography and hybrid positron emission tomography-magnetic resonance imaging (PET-MRI) are also explored, offering high-resolution imaging and combined metabolic and structural insights, respectively. Finally, wearable technology and biosensors for real-time monitoring of osteoarthritis progression, as well as the role of artificial intelligence in enhancing diagnostic accuracy through pattern recognition in imaging data are addressed. While these advanced diagnostic tools hold great potential for early detection and monitoring of osteoarthritis, challenges remain in clinical translation, including validation in larger populations and integration into existing clinical workflows and personalized treatment strategies for cartilage-related diseases.

Functional Monitoring of Patients With Knee Osteoarthritis Based on Multidimensional Wearable Plantar Pressure Features: Cross-Sectional Study

BACKGROUND

Patients with knee osteoarthritis (KOA) often present lower extremity motor dysfunction. However, traditional radiography is a static assessment and cannot achieve long-term dynamic functional monitoring. Plantar pressure signals have demonstrated potential applications in the diagnosis and rehabilitation monitoring of KOA.

OBJECTIVE

Through wearable gait analysis technology, we aim to obtain abundant gait information based on machine learning techniques to develop a simple, rapid, effective, and patient-friendly functional assessment model for the KOA rehabilitation process to provide long-term remote monitoring, which is conducive to reducing the burden of social health care system.

METHODS

This cross-sectional study enrolled patients diagnosed with KOA who were able to walk independently for 2 minutes. Participants were given clinically recommended functional tests, including the 40-m fast-paced walk test (40mFPWT) and timed up-and-go test (TUGT). We used a smart shoe system to gather gait pressure data from patients with KOA. The multidimensional gait features extracted from the data and physical characteristics were used to establish the KOA functional feature database for the plantar pressure measurement system. 40mFPWT and TUGT regression prediction models were trained using a series of mature machine learning algorithms. Furthermore, model stacking and average ensemble learning methods were adopted to further improve the generalization performance of the model. Mean absolute error (MAE), mean absolute percentage error (MAPE), and root mean squared error (RMSE) were used as regression performance metrics to evaluate the results of different models.

RESULTS

A total of 92 patients with KOA were included, exhibiting varying degrees of severity as evaluated by the Kellgren and Lawrence classification. A total of 380 gait features and 4 physical characteristics were extracted to form the feature database. Effective stepwise feature selection determined optimal feature subsets of 11 variables for the 40mFPWT and 10 variables for the TUGT. Among all models, the weighted average ensemble model using 4 tree-based models had the best generalization performance in the test set, with an MAE of 2.686 seconds, MAPE of 9.602%, and RMSE of 3.316 seconds for the prediction of the 40mFPWT and an MAE of 1.280 seconds, MAPE of 12.389%, and RMSE of 1.905 seconds for the prediction of the TUGT.

CONCLUSIONS

This wearable plantar pressure feature technique can objectively quantify indicators that reflect functional status and is promising as a new tool for long-term remote functional monitoring of patients with KOA. Future work is needed to further explore and investigate the relationship between gait characteristics and functional status with more functional tests and in larger sample cohorts.

Krill Oil for Knee Osteoarthritis: A Randomized Clinical Trial

Importance

Knee osteoarthritis is disabling, with few effective treatments. Preliminary evidence suggested that krill oil supplementation improved knee pain, but effects on knee osteoarthritis remain unclear.

Objective

To evaluate efficacy of krill oil supplementation, compared with placebo, on knee pain in people with knee osteoarthritis who have significant knee pain and effusion-synovitis.

Design, Setting, and Participants

Multicenter, randomized, double-blind, placebo-controlled clinical trial in 5 Australian cities. Participants with clinical knee osteoarthritis, significant knee pain, and effusion-synovitis on magnetic resonance imaging were enrolled from December 2016 to June 2019; final follow-up occurred on February 7, 2020.

Interventions

Participants were randomized to 2 g/d of krill oil (n = 130) or matching placebo (n = 132) for 24 weeks.

Main Outcomes and Measures

The primary outcome was change in knee pain as assessed by visual analog scale (range, 0-100; 0 indicating least pain; minimum clinically important improvement = 15) over 24 weeks.

Results

Of 262 participants randomized (mean age, 61.6 [SD, 9.6] years; 53% women), 222 (85%) completed the trial. Krill oil did not improve knee pain compared with placebo (mean change in VAS score, -19.9 [krill oil] vs -20.2 [placebo]; between-group mean difference, -0.3; 95% CI, -6.9 to 6.4) over 24 weeks. One or more adverse events was reported by 51% in the krill oil group (67/130) and by 54% in the placebo group (71/132). The most common adverse events were musculoskeletal and connective tissue disorders, which occurred 32 times in the krill oil group and 42 times in the placebo group, including knee pain (n = 10 with krill oil; n = 9 with placebo), lower extremity pain (n = 1 with krill oil; n = 5 with placebo), and hip pain (n = 3 with krill oil; n = 2 with placebo).

Conclusions and Relevance

Among people with knee osteoarthritis who have significant knee pain and effusion-synovitis on magnetic resonance imaging, 2 g/d of daily krill oil supplementation did not improve knee pain over 24 weeks compared with placebo. These findings do not support krill oil for treating knee pain in this population.

Trial Registration

Australian New Zealand Clinical Trials Registry Identifier: ACTRN12616000726459; Universal Trial Number: U1111-1181-7087.

Ambulatory support moment contribution patterns and MRI-detected tibiofemoral and patellofemoral disease worsening in adults with knee osteoarthritis: A preliminary study

We investigated whether baseline sagittal-plane ankle, knee, and hip contribution to the total support moment (TSM) are each associated with baseline-to-2-year tibiofemoral and patellofemoral tissue damage worsening in adults with knee osteoarthritis. Ambulatory lower-limb kinetics were captured and computed. TSM is the sum of ankle, knee, and hip extensor moments at each instant during gait. Ankle, knee, and hip contributions to TSM were computed as joint moments divided by TSM, expressed as percentages. Participants underwent MRI of both knees at baseline and 2 years later. Logistic regression models assessed associations of baseline ankle contribution to TSM with baseline-to-2-year cartilage damage and bone marrow lesion worsening, adjusted for age, sex, BMI, gait speed, disease severity, and pain. We used similar analytic approaches for knee and hip contributions to TSM. Sample included 391 knees from 204 persons (age[SD]: 64[10] years; 76.5% women). Greater ankle contribution may be associated with increased odds of tibiofemoral cartilage damage worsening (OR = 2.38; 95% CI: 1.02-5.57) and decreased odds of patellofemoral bone marrow lesion worsening (OR = 0.14; 95% CI: 0.03-0.73). The ORs for greater knee contribution were in the protective range for tibiofemoral compartment and in the deleterious range for patellofemoral. Greater hip contribution may be associated with increased odds of tibiofemoral worsening (OR = 2.71; 95% CI: 1.17-6.30). Greater ankle contribution to TSM may be associated with baseline-to-2-year tibiofemoral worsening, but patellofemoral tissue preservation. Conversely, greater knee contribution may be associated with patellofemoral worsening, but tibiofemoral preservation. Preliminary findings illustrate potential challenges in developing biomechanical interventions beneficial to both tibiofemoral and patellofemoral compartments.

Assessing Site Specificity of Osteoarthritic Gait Kinematics with Wearable Sensors and Their Association with Patient Reported Outcome Measures (PROMs): Knee versus Hip Osteoarthritis

There is a great need for quantitative outcomes reflecting the functional status in patients with knee or hip osteoarthritis (OA) to advance the development and investigation of interventions for OA. The purpose of this study was to determine if gait kinematics specific to the disease—i.e., knee versus hip OA—can be identified using wearable sensors and statistical parametric mapping (SPM) and whether disease-related gait deviations are associated with patient reported outcome measures. 113 participants (N = 29 unilateral knee OA; N = 30 unilateral hip OA; N = 54 age-matched asymptomatic persons) completed gait analysis with wearable sensors and the Knee/Hip Osteoarthritis Outcome Score (KOOS/HOOS). Data were analyzed using SPM. Knee and hip kinematics differed between patients with knee OA and patients with hip OA (up to 14°, p < 0.001 for knee and 8°, p = 0.003 for hip kinematics), and differences from controls were more pronounced in the affected than unaffected leg of patients. The observed deviations in ankle, knee and hip kinematic trajectories from controls were associated with KOOS/HOOS in both groups. Capturing gait kinematics using wearables has a large potential for application as outcome in clinical trials and for monitoring treatment success in patients with knee or hip OA and in large cohorts representing a major advancement in research on musculoskeletal diseases.

Defining the rate of, and factors influencing, radiographic progression of osteoarthritis of the canine hip joint

BACKGROUND

This study aimed to define the rate of progression of radiographic osteoarthritis (OA) of the canine hip joint and to describe factors affecting this progression.

METHODS

Dogs that underwent unilateral total hip replacement (THR) were reviewed for the evaluation of radiographic appearance of the non-operated hip joint over time. Standard extended ventrodorsal hip radiographs were taken preoperatively and postoperatively. All images were anonymized, randomized and scored using three different methods. The mean daily change between evaluations was calculated in each individual dog, and the effect of sex, age, body weight, open/closed status of the proximal femoral physis, preoperative severity of OA, time after surgery and their interactions, were investigated as potential influencing factors.

RESULTS

After reviewing the medical records, 163 dogs (468 images) met the inclusion criteria. Consistent across the three scoring systems, radiographic progression of OA was greater in younger (open physis) and spayed female dogs. A subset of seven patients (4.3%) had a faster progression of OA and was considered outliers. No dog was rated as outlier by all three scoring systems.

CONCLUSION

The rate of progression of radiographically assessed coxofemoral OA varies greatly, but is faster in younger, spayed female dogs. Unusually fast progression occasionally occurs.

The Longitudinal Relationship Between Physical Activity and Joint Space Narrowing: 48-Month Follow-Up Data from the Osteoarthritis Initiative

OBJECTIVE

To determine whether amount of physical activity (PA) is a determinant of joint space narrowing (JSN) worsening over 48-months in participants with knee osteoarthritis (OA).

METHODS

Data were obtained from the Osteoarthritis Initiative. PA, measured using the Physical Activity Scale for the Elderly (PASE), was defined as the mean value of the annual measurements conducted prior to development of worsening JSN. Worsening JSN was defined as at least a partial grade increase in OARSI JSN score over 48 months, in comparison with baseline. Restricted cubic spline (RCS) function was used to group participants based on the linear association between PA and JSN worsening. A pooled logistic regression model was used to evaluate the association between PA and JSN worsening adjusted for confounders.

RESULTS

2,167 participants were included. In total, 625 (28.8%) participants had JSN worsening over 48 months. Compared with PASE score of 140-180, PASE scores of 100-140 and >220 associated with an increased risk of JSN worsening in men with OR (95% CI) of 1.73 (1.07, 2.81) and 1.83 (1.14, 2.93) respectively. Similarly, in participants with Kellgren and Lawrence grade 2, compared with a PASE score of 140-180, PASE score of <100 and >220 were associated with increased risks of JSN worsening, with OR (95% CIs) of 1.69 (1.13, 2.54) and 1.64 (1.05, 2.56) respectively.

CONCLUSION

Compared to moderate PA, higher or lower amounts of PA are associated with elevated risk for JSN worsening in men and in participants with KL grade 2 knees.

Cross-Talk between Diet-Associated Dysbiosis and Hand Osteoarthritis

Hand osteoarthritis (OA) is a degenerative joint disease which leads to pain and disability. Recent studies focus on the role of obesity and metabolic syndrome in inducing or worsening joint damage in hand OA patients, suggesting that chronic low-grade systemic inflammation may represent a possible linking factor. The gut microbiome has a crucial metabolic role which is fundamental for immune system development, among other important functions. Intestinal microbiota dysbiosis may favour metabolic syndrome and low-grade inflammation-two important components of hand OA onset and evolution. The aim of this narrative is to review the recent literature concerning the possible contribution of dysbiosis to hand OA onset and progression, and to discuss the importance of gut dysbiosis on general health and disease.

Biomarkers as drug development tools: discovery, validation, qualification and use

The 21st Century Cures Act, approved in the USA in December 2016, has encouraged the establishment of the national Precision Medicine Initiative and the augmentation of efforts to address disease prevention, diagnosis and treatment on the basis of a molecular understanding of disease. The Act adopts into law the formal process, developed by the FDA, of qualification of drug development tools, including biomarkers and clinical outcome assessments, to increase the efficiency of clinical trials and encourage an era of molecular medicine. The FDA and European Medicines Agency (EMA) have developed similar processes for the qualification of biomarkers intended for use as companion diagnostics or for development and regulatory approval of a drug or therapeutic. Biomarkers that are used exclusively for the diagnosis, monitoring or stratification of patients in clinical trials are not subject to regulatory approval, although their qualification can facilitate the conduct of a trial. In this Review, the salient features of biomarker discovery, analytical validation, clinical qualification and utilization are described in order to provide an understanding of the process of biomarker development and, through this understanding, convey an appreciation of their potential advantages and limitations.

A protocol for a multicentre, randomised, double-blind, placebo-controlled trial to compare the effect of annual infusions of zoledronic acid to placebo on knee structural change and knee pain over 24 months in knee osteoarthritis patients - ZAP2

BACKGROUND

Bisphosphonates are a class of drugs that slow bone loss and are a promising candidate to treat knee osteoarthritis (OA) patients. In a pilot study, we demonstrated that zoledronic acid reduced knee pain and size of subchondral bone marrow lesions (BMLs) over 6 months in knee OA patients with significant knee pain and BMLs. A longer, larger study is required to assess whether decreases in BML size will translate to reductions in cartilage loss over time. We are currently conducting a multicentre, randomised, double-blind, placebo-controlled trial over 24 months that aims to compare the effect of annual infusions of zoledronic acid to placebo on knee structural change (assessed using magnetic resonance imaging (MRI)) and knee pain in knee OA patients.

METHODS

Two hundred sixty-four patients with clinical knee OA, significant knee pain and subchondral BMLs present on MRI will be recruited in Hobart, Melbourne, Sydney and Adelaide. They will be randomly allocated to the two arms of the study, receiving an annual identical intravenous infusion of either 100 mL of fluid containing zoledronic acid (5 mg/100 mL) or placebo (0.9% NaCl 100 mL), at baseline and 1 year later. MRI of the study knee will be performed at screening, month 6 and 24. Knee structure, symptoms and function will be assessed using validated methods. The primary outcome is absolute change in tibiofemoral cartilage volume (mm3) over 24 months. Secondary outcomes include improvement in knee pain over 3, 6, 12, 18, and 24 months and reductions in BML size over 6 and 24 months. The primary analyses will be intention-to-treat analyses of primary and secondary outcomes. Per protocol analyses will be performed as the secondary analyses.

DISCUSSION

This study will provide high-quality evidence to assess whether zoledronic acid has a novel disease modifying effect in OA by slowing cartilage loss and reducing pain. If zoledronic acid proves effective, it suggests great potential for cost savings through a delay or reduced need for joint replacement surgery, and potential for great improvements in quality of life for OA suffers.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12613000039785 , registered on 14 January 2013.

Extracellular genomic biomarkers of osteoarthritis

INTRODUCTION

Osteoarthritis (OA), a chronic, debilitating and degenerative disease of the joints, is the most common form of arthritis. The seriousness of this prevalent and chronic disease is often overlooked. Disease modifying OA drug development is hindered by the lack of soluble biomarkers to detect OA early. The objective of OA biomarker research is to identify early OA prior to the appearance of radiographic signs and the development of pain. Areas covered: This review has focused on extracellular genomic material that could serve as biomarkers of OA. Recent studies have examined the expression of extracellular genomic material such as miRNA, lncRNA, snoRNA, mRNA and cell-free DNA, which are aberrantly expressed in the body fluids of OA patients. Changes in genomic content of peripheral blood mononuclear cells in OA could also function as biomarkers of OA. Expert commentary: There is an unmet need for soluble biomarkers for detecting and then monitoring OA disease progression. Extracellular genomic material research may also reveal more about the underlying pathophysiology of OA. Minimally-invasive liquid biopsies such as synovial fluid and blood sampling of genomic material may be more sensitive over radiography in the detection, diagnosis and monitoring of OA in the future.