Biomechanical modeling and imaging for knee osteoarthritis – is there a role for AI?

Abstract Objective: This mini review aims to assess the latest advancements in the field of osteoarthritis (OA) research, particularly focusing on the early detection and prediction of disease progression through the use of advanced imaging technologies utilizing biomechanical modeling and artificial intelligence (AI). Design: The review consolidates and discusses findings from studies that utilize biomechanical modeling and/or machine learning algorithms to identify pathological changes in joint tissues indicative of OA or prediction of disease progression. It also briefly reviews future research and how these methods could be used as a part of OA management. Results: AI algorithms have proven highly effective in recognizing the subtle changes in joint tissues associated with OA and in identifying patients at high risk for the disease. While these automated tools facilitate early diagnosis, they typically do not provide personalized intervention strategies to prevent disease progression. AI-enhanced biomechanical modeling has the potential to simulate the effects of various conservative interventions (e.g., weight management, optimal footwear, and gait retraining) on slowing OA progression, which could be pivotal for patient engagement and preventive care. Conclusions: The integration of AI with biomechanical modeling holds significant promise for enhancing the management of OA by not only predicting disease onset and progression but also by enabling personalized intervention plans. Future research should focus on the development of these models to include personalized, preventive strategies that could effectively engage patients and potentially delay or prevent the onset of OA. This approach could revolutionize patient care by making early, targeted intervention feasible.Abstract Objective: This mini review aims to assess the latest advancements in the field of osteoarthritis (OA) research, particularly focusing on the early detection and prediction of disease progression through the use of advanced imaging technologies utilizing biomechanical modeling and artificial intelligence (AI). Design: The review consolidates and discusses findings from studies that utilize biomechanical modeling and/or machine learning algorithms to identify pathological changes in joint tissues indicative of OA or prediction of disease progression. It also briefly reviews future research and how these methods could be used as a part of OA management. Results: AI algorithms have proven highly effective in recognizing the subtle changes in joint tissues associated with OA and in identifying patients at high risk for the disease. While these automated tools facilitate early diagnosis, they typically do not provide personalized intervention strategies to prevent disease progression. AI-enhanced biomechanical modeling has the potential to simulate the effects of various conservative interventions (e.g., weight management, optimal footwear, and gait retraining) on slowing OA progression, which could be pivotal for patient engagement and preventive care. Conclusions: The integration of AI with biomechanical modeling holds significant promise for enhancing the management of OA by not only predicting disease onset and progression but also by enabling personalized intervention plans. Future research should focus on the development of these models to include personalized, preventive strategies that could effectively engage patients and potentially delay or prevent the onset of OA. This approach could revolutionize patient care by making early, targeted intervention feasible

The Influence of Radiographic Severity on the Relationship between Muscle Strength and Joint Loading in Obese Knee Osteoarthritis Patients

Objective. To investigate the relationship between knee muscle strength and the external knee adduction moment during walking in obese knee osteoarthritis patients and whether disease severity influences this relationship. Methods. This cross-sectional study included 136 elderly obese (BMI > 30) adults with predominant medial knee osteoarthritis. Muscle strength, standing radiographic severity as measured by the Kellgren and Lawrence scale, and the peak external knee adduction moment were measured at self-selected walking speed. Results. According to radiographic severity, patients were classified as “less severe” (KL 1-2, N = 73) or “severe” (KL 3-4, N = 63). A significant positive association was demonstrated between the peak knee adduction moment and hamstring muscle strength in the whole cohort (P = .047). However, disease severity did not influence the relationship between muscle strength and dynamic medial knee joint loading. Severe patients had higher peak knee adduction moment and more varus malalignment (P < .001). Conclusion. Higher hamstring muscle strength relates to higher estimates of dynamic knee joint loading in the medial compartment. No such relationship existed for quadriceps muscle strength. Although cross sectional, the results suggest that hamstrings function should receive increased attention in future studies and treatments that aim at halting disease progression

Effect of growth hormone on aging connective tissue in muscle and tendon - gene expression, morphology and function following immobilization and rehabilitation

It is unknown whether loss in musculotendinous tissue during inactivity can be counteracted by growth hormone (GH), and whether GH accelerate rehabilitation in aging individuals. Elderly men (65–75 yr; n = 12) had one leg immobilized 2 wk followed by 6 wk of retraining and were randomly assigned to daily injections of recombinant GH (rhGH; n = 6) or placebo (Plc; n = 6). Cross-sectional area (CSA), muscle strength (MVC), and biomechanical properties of m. quadriceps and patellar tendon were determined. Muscle and tendon biopsies were analyzed for gene expressions (mRNA) of collagen (COL1A1/3A1) and insulin-like growth factors (IGF-1Ea/Ec). Fibril morphology was analyzed by transmission electron microscope (TEM). In tendon, CSA and biomechanical properties did not change following immobilization, but an increase in CSA was found after 6 wk of rehabilitation in both groups. The changes were more pronounced when GH was injected. Furthermore, tendon stiffness increased in the GH group. Muscle CSA declined after immobilization in the Plc but not in the GH group. Muscle CSA increased during retraining, with a significantly larger increase in the GH group compared with the Plc group. Both a time and a group effect were seen for IGF-1Ea/Ec and COL1A1/3A1 mRNA expression in muscle, with a difference between GH and Plc. IGF-1Ea/Ec and COL-1A1/3A1 mRNA expression increased in muscle following immobilization and retraining in subjects receiving GH, whereas an increase in IGF-1Ec mRNA expression was seen in the Plc group only after retraining. In conclusion, in elderly humans, GH seems to have a matrix stabilizing effect during inactivity and rehabilitation by stimulating collagen expression in the musculotendinous tissue and increasing tendon CSA and stiffness.</jats:p

Dynamic Contrast Enhanced MRI Can Monitor the Very Early Inflammatory Treatment Response upon Intra-Articular Steroid Injection in the Knee Joint: A Case Report with Review of the Literature

Dynamic contrast-enhanced MRI in inflammatory arthritis, especially in conjunction with computer-aided analysis using appropriate dedicated software, seems to be a highly sensitive tool for monitoring the early inflammatory treatment response in patients with rheumatoid arthritis. This paper gives a review of the current knowledge of the emerging technique. The potential of the technique is demonstrated and discussed in the context of a case report following the early effect of an intra-articular steroid injection in a patient with rheumatoid arthritis flare in the knee

Evaluation of serum ARGS neoepitope as an osteoarthritis biomarker using a standardized model for exercise-induced cartilage extra cellular matrix turnover

Summary: Objective: To propose a standardized model for exercise-induced cartilage turnover and investigate residual levels and dynamics of biomarker serum ARGS (sARGS) in primary osteoarthritis (OA) patients and a supportive group of young healthy subjects. Method: The trial is a randomized, cross-over, exploratory study with interventions of exercise and inactivity. 20 subjects with knee OA, as well as 20 young healthy subjects (mean age 25.7 years (range; 19–30), 50% male), underwent cycling, running and resting interventions on separate days one week apart. Blood samples were taken at baseline, immediately, 1, 2, 3 and 24 h after activity start. sARGS was measured by sandwich ELISA. Results: Intraclass correlation between visits were 0.97 and 0.77 for the OA and healthy group, respectively. An acute drop in sARGS in response to high-intensity exercise was observed in both groups. Minute acute sARGS increase was observed in OA subjects in response to moderate intensity running and cycling, which normalized within 24 h. In healthy subjects an acute drop in sARGS was seen immediately after running, but not cycling, and no other changes were observed. A negative correlation between baseline Kellgren-Lawrence (KL) grade and baseline sARGS (r = −0.69, p = 0.002) in OA was found. A negative correlation between age and sARGS was found in healthy subjects (r = −0.67, p = <0.002). Conclusion: sARGS sensitivity to physical activity is considered low and sARGS is a reproducible and stable marker. Minute acute increases in sARGS were observed in the hours following moderate intensity exercise

Synovial explant inflammatory mediator production corresponds to rheumatoid arthritis imaging hallmarks:a cross-sectional study

Introduction: Despite the widespread use of magnetic resonance imaging (MRI) and Doppler ultrasound for the detection of rheumatoid arthritis (RA) disease activity, little is known regarding the association of imaging-detected activity and synovial pathology. The purpose of this study was to compare site-specific release of inflammatory mediators and evaluate the corresponding anatomical sites by examining colour Doppler ultrasound (CDUS) and MRI scans.Methods: RA patients were evaluated on the basis of CDUS and 3-T MRI scans and subsequently underwent synovectomy using a needle arthroscopic procedure of the hand joints. The synovial tissue specimens were incubated for 72 hours, and spontaneous release of monocyte chemoattractant protein 1 (MCP-1), interleukin 6 (IL-6), macrophage inflammatory protein 1β (MIP-1β) and IL-8 was measured by performing multiplex immunoassays. Bone marrow oedema (BME), synovitis and erosion scores were estimated on the basis of the rheumatoid arthritis magnetic resonance imaging score (RAMRIS). Mixed models were used for the statistical analyses. Parsimony was achieved by omitting covariates with P > 0.1 from the statistical model.Results: Tissue samples from 58 synovial sites were obtained from 25 patients. MCP-1 was associated with CDUS activity (P = 0.009, approximate Spearman's ρ = 0.41), RAMRIS BME score (P = 0.01, approximate Spearman's ρ = 0.42) and RAMRIS erosion score (P = 0.03, approximate Spearman's ρ = 0.31). IL-6 was associated with RAMRIS synovitis score (P = 0.04, approximate Spearman's ρ = 0.50), BME score (P = 0.04, approximate Spearman's ρ = 0.31) and RAMRIS erosion score (P = 0.03, approximate Spearman's ρ = 0.35). MIP-1β was associated with CDUS activity (P = 0.02, approximate Spearman's ρ = 0.38) and RAMRIS synovitis scores (P = 0.02, approximate Spearman's ρ = 0.63). IL-8 associations with imaging outcome measures did not reach statistical significance.Conclusions: The association between imaging activity and synovial inflammatory mediators underscores the high sensitivity of CDUS and MRI in the evaluation of RA disease activity. The associations found in our present study have different implications for synovial mediator releases and corresponding imaging signs. For example, MCP-1 and IL-6 were associated with both general inflammation and bone destruction, in contrast to MIP-1β, which was involved solely in general synovitis. The lack of association of IL-8 with synovitis was likely underestimated because of a large proportion of samples above assay detection limits among the patients with the highest synovitis scores. © 2014 Andersen et al.; licensee BioMed Central Ltd

Effect of repeated prolonged exercise on liver fat content and visceral adipose tissue in well-trained older men

Publisher Copyright: © 2024 The Authors. Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd.Introduction: Liver fat (LF) and visceral adipose tissue (VAT) content decreases with training, however, this has mainly been investigated in sedentary obese or healthy participants. The aim of this study was to investigate the effects of repeated prolonged exercise on LF and VAT content in well-trained older men and to compare baseline LF and VAT content to recreationally active older men. Method: A group of five well-trained older men were tested before and after cycling a total distance of 2558 km in 16 consecutive days. VAT content and body composition was measured using DXA before a bicycle ergometer test was performed to determine maximal fat oxidation (MFO), maximal oxygen consumption ((Formula presented.)), and the relative intensity at which MFO occurred (Fatmax). LF content was measured on a separate day using MRI. For comparison of baseline values, a control group of eight healthy age- and BMI-matched recreationally active men were recruited. Results: The well-trained older men had lower VAT (p = 0.02), and a tendency toward lower LF content (p = 0.06) compared with the control group. The intervention resulted in decreased LF content (p = 0.02), but VAT, fat mass, and lean mass remained unchanged. (Formula presented.), MFO, and Fatmax were not affected by the intervention. Conclusion: The study found that repeated prolonged exercise reduced LF content, but VAT and (Formula presented.) remained unchanged. Aerobic capacity was aligned with lower LF and VAT in older active men.Peer reviewe