Association of metabolic risk factors with cartilage degradation assessed by T2 relaxation time at the knee: data from the osteoarthritis initiative

A novel whole "Joint-in-Motion" device reveals a permissive effect of high glucose levels and mechanical stress on joint destruction

OBJECTIVE

Osteoarthritis (OA) has recently been suggested to be associated with diabetes. However, this association often disappears when accounting for body mass index (BMI), suggesting that mechanical stress may be a confounding factor. We investigated the combined influence of glucose level and loading stress on OA progression using a novel whole joint-in-motion (JM) culture system.

DESIGN

Whole mouse knee joints were placed in an enclosed chamber with culture media and actuated to recapitulate leg movement, with a dynamic stress regimen of 0.5 Hz, 8 h/day for 7 days. These joints were treated with varying levels of glucose and controlled for osmolarity and diffusion. Joint movement and joint space were examined by X-ray fluoroscopy and microCT. Cartilage matrix levels were quantified by blinded Mankin scoring and immunohistochemistry.

RESULTS

Culturing in the JM device facilitated proper leg extension and flexion movements, and adequate mass transport for analyzing the effect of glucose on cartilage. Treatment with higher levels of glucose either via media supplementation or intra-articular injection caused a significant decrease in levels of glycosaminoglycan (GAG) and an increase in aggrecan neoepitope in articular cartilage, but only under dynamic stress. Additionally, collagen II level was slightly reduced by high glucose levels.

CONCLUSIONS

High levels of glucose and dynamic stress have permissive effects on articular cartilage GAG loss and aggrecan degradation, implicating that mechanical stress confounds the association of diabetes with OA. The JM device supports novel investigation of mechanical stress on the integrity of an intact living mouse joint to provide insights into OA pathogenesis.

Effects of a Mediterranean Diet Compared with the Low-Fat Diet on Patients with Knee Osteoarthritis: A Randomized Feeding Trial

OBJECTIVES

Knee osteoarthritis is a common global problem, especially in overweight and obese people. It is not clear that weight loss is a factor for pain reduction in these patients or dietary components are important. Herein, we compared the effects of Mediterranean (MD) and low-fat diet on pain, stiffness, and physical function in patients with knee osteoarthritis.

SUBJECTS

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METHODS

In this randomized feeding trial, 129 patients with knee osteoarthritis were enrolled. Participants were randomly allocated to the MD (n = 43), low-fat diet (n = 43), and control group (regular diet) (n = 43) for 12 weeks by the blocked randomization method. Total Western Ontario and McMaster Universities Arthritis Index (WOMAC) score and its subscales and anthropometric indices were compared among the groups at the baseline and end of the study.

RESULTS

Weight and waist circumference reduction was significantly higher in the MD and low-fat diet groups compared with the regular group (p < 0.001 and p < 0.001, respectively), but there was no significant difference between the MD and low-fat diet groups (p = 0.2). Pain was significantly decreased in the Mediterranean-style compared with the low-fat (p = 0.04) and regular (p = 0.002) diet groups. Physical function was significantly improved in the MD compared with the regular diet group (p = 0.01), but had no significant difference with the low-fat one. Stiffness had no significant difference among the dietary groups.

CONCLUSIONS

Pain severity was reduced in the MD group, but no significant change was reported in patients on low-fat and regular diets. It seems that dietary components in the MD, regardless of weight loss effect, are effective on pain reduction in patients with KOA. The present study was registered in the IRCT under the code of IRCT20200929048876N1.

Accelerated osteoarthritis in women with polycystic ovary syndrome: a prospective nationwide registry-based cohort study

BACKGROUND

Osteoarthritis (OA) is the most common form of arthritis with multiple risk factors implicated including female sex and obesity. Metabolic dysregulation associated with obesity leading to metabolic syndrome is a proposed component of that association. Polycystic ovary syndrome (PCOS) commonly affects women of reproductive age and these women are at higher risk of developing metabolic syndrome and thus likely to represent a high-risk group for early OA development. There are no published studies exploring the epidemiology of knee, hip and hand OA in women diagnosed with PCOS.

STUDY AIM

To assess the prevalence and incidence of knee, hip and hand osteoarthritis (OA) in women with polycystic ovary syndrome (PCOS) when compared with age-matched controls.

METHODS

Prospective Danish national registry-based cohort study. The prevalence of OA in 2015 and incidence rates of OA over 11.1 years were calculated and compared in more than 75,000 Danish women with either a documented diagnosis of PCOS ± hirsutism (during the period of 1995 to 2012) or age-matched females without those diagnoses randomly drawn from the same population register.

RESULTS

In 2015, the prevalence of hospital treated knee, hip and hand OA was 5.2% in women with PCOS diagnosis. It was 73% higher than that seen in age-matched controls. Significantly higher incidence rates were observed in the PCOS cohort compared with the age-matched controls during the follow-up period (up to 20 years), with the following hazard ratios (HR): 1.9 (95% CI 1.7 to 2.1) for knee, 1.8 (95% CI 1.3-2.4) for hand and 1.3 (95% CI 1.1 to 1.6) for hip OA. After excluding women with obesity, similar associations were observed for knee and hand OA. However, risk of developing hip OA was no longer significant.

CONCLUSIONS

In this large prospective study, women with PCOS diagnosis had higher prevalence and accelerated onset of OA of both weight and non-weight bearing joints, when compared with age-matched controls. Further studies are needed to understand the relative effect of metabolic and hormonal changes linked with PCOS and their role in promoting development of OA.

Anterior cruciate ligament abnormalities are associated with accelerated progression of knee joint degeneration in knees with and without structural knee joint abnormalities: 96-month data from the Osteoarthritis Initiative

OBJECTIVE

To compare progression over 8 years in knee compositional cartilage degeneration and structural joint abnormalities in knees with different types of anterior cruciate ligament (ACL) abnormalities over 8 years.

METHOD

Baseline MR images of the right knees of 1899 individuals of the Osteoarthritis Initiative (OAI) with no evidence of or mild to moderate radiographic osteoarthritis were assessed for nontraumatic ACL abnormalities. The knees of 91 individuals showed nontraumatic ACL abnormalities (age 60.6 ± 9.8 y, 46 females; mucoid degeneration (MD), N = 37; complete tear (CT), N = 22; partial tear (PT), N = 32) and were frequency-matched to 91 individuals with normal ACL. MRIs were assessed for knee joint abnormalities using the Whole-Organ Magnetic Resonance Imaging Score (WORMS) and cartilage T2 mapping at baseline, 4- and 8-year follow-up.

RESULTS

Over 8 years, cartilage T2 values of the medial tibia showed a significantly greater increase in individuals with MD, PT or CT compared to those with normal ACL (adjusted rate of change/year [95% confidence interval], normal ACL: 0.06 [0.01, 0.23], MD: 0.34 [0.07, 0.73], PT, 0.21 [0.02, 0.33], CT, 0.51 [0.16, 0.78]), indicating an association of ACL abnormalities and an increased progression rate of cartilage degeneration in subjects with and without knee joint degeneration. This effect was also seen in cartilage T2 values averaged over all compartments (normal ACL: 0.08 [0.05, 0.20] vs abnormal ACL: 0.27 [0.06, 0.56]).

CONCLUSIONS

Over 8 years, higher progression rates of cartilage degeneration, especially in the medial tibia, were associated with ACL abnormalities compared to those with normal ACL, in subjects with and without knee joint abnormalities.

Impact of Diabetes Mellitus on Knee Osteoarthritis Pain and Physical and Mental Status: Data From the Osteoarthritis Initiative

OBJECTIVE

Diabetes mellitus (DM) appears to increase osteoarthritic knee pain, which may be related to greater adiposity and more advanced disease status often observed in individuals with osteoarthritis (OA) and DM. We aimed to assess whether OA knee pain and health status are worse in individuals with OA and DM, independent of these potential confounders.

METHODS

We included 202 OA participants with DM and 2,279 without DM from the Osteoarthritis Initiative. Knee pain was evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and a numeric rating scale (NRS). Physical and mental status were assessed by the Medical Outcomes Study Short Form 12 (SF-12) questionnaire, physical component summary (PCS) score and mental component summary (MCS) score, and by the Center for Epidemiologic Studies Depression Scale (CES-D). Linear regression models assessed the influence of DM, adjusted for age, sex, body mass index (BMI), and radiographic severity.

RESULTS

OA participants with DM reported worse knee pain and greater physical and mental issues compared with participants without DM. Individuals with DM had worse KOOS pain (β = -4.72 [95% confidence interval (95% CI) -7.22, -2.23]) and worse NRS pain (β = 0.42 [95% CI 0.04, 0.80]) independent of BMI, OA severity, age, and sex. The negative influence of DM was also apparent for SF-12 PCS (β = -3.49 [95% CI -4.73, -2.25]), SF-12 MCS (β = -1.42 [95% CI -2.57, -0.26]), and CES-D (β = 1.08 [95% CI 0.08, 2.08]).

CONCLUSION

Individuals with knee OA experience on average higher pain intensity and a worse physical and mental health status if they have DM. Linear regression models show that DM is a risk factor for higher pain, in addition to and independent of greater BMI and radiographic OA severity.

T2 analysis of the entire osteoarthritis initiative dataset

While substantial work has been done to understand the relationships between cartilage T₂ relaxation times and osteoarthritis (OA), diagnostic and prognostic abilities of T₂ on a large population yet need to be established. Using 3921 manually annotated 2D multi-slice multi-echo spin-echo magnetic resonance imaging volume, a segmentation model for automatic knee cartilage segmentation was built and evaluated. The optimized model was then used to calculate T₂ values on the entire osteoarthritis initiative (OAI) dataset composed of longitudinal acquisitions of 4796 unique patients, 25 729 magnetic resonance imaging studies in total. Cross-sectional relationships between T₂ values, OA risk factors, radiographic OA, and pain were analyzed in the entire OAI dataset. The performance of T₂ values in predicting the future incidence of radiographic OA as well as total knee replacement (TKR) were also explored. Automatic T₂ values were comparable with manual ones. Significant associations between T₂ relaxation times and demographic and clinical variables were found. Subjects in the highest 25% quartile of tibio-femoral T₂ values had a five times higher risk of radiographic OA incidence 2 years later. Elevation of medial femur T₂ values was significantly associated with TKR after 5 years (coeff = 0.10; P = .036; CI = [0.01,0.20]). Our investigation reinforces the predictive value of T₂ for future incidence OA and TKR. The inclusion of T₂ averages from the automatic segmentation model improved several evaluation metrics when compared to only using demographic and clinical variables.

Setting up distinctive outcome measures for each osteoarthritis phenotype

Osteoarthritis (OA) is an evolving chronic joint disease with a huge global impact. Given the intricate nature of the etiopathogenesis and subsequent high heterogeneity in the clinical course of OA, it is crucial to discriminate between etiopathogenic endotypes and clinical phenotypes, especially in the early stages of the disease. In this sense, we propose that an OA phenotype should be properly assessed with a set of outcome measures including those specifically related to the main underlying pathophysiological mechanisms. Thus, each OA phenotype can be related to different and clinically meaningful outcomes. OA phenotyping would lead to an adequate patient stratification in well-designed clinical trials and the discovery of precise therapeutic approaches. A significant effort will be required in this field in light of inconclusive results of clinical trials of tissue-targeting agents for the treatment of OA.

Association of blood pressure with knee cartilage composition and structural knee abnormalities: data from the osteoarthritis initiative

OBJECTIVE

To investigate the associations of systolic blood pressure (SBP) and diastolic blood pressure (DBP) with changes in knee cartilage composition and joint structure over 48 months, using magnetic resonance imaging (MRI) data from the Osteoarthritis Initiative (OAI).

MATERIALS AND METHODS

A total of 1126 participants with right knee Kellgren-Lawrence (KL) score 0-2 at baseline, no history of rheumatoid arthritis, blood pressure measurements at baseline, and cartilage T2 measurements at baseline and 48 months were selected from the OAI. Cartilage composition was assessed using MRI T2 measurements, including laminar and gray-level co-occurrence matrix texture analyses. Structural knee abnormalities were graded using the whole-organ magnetic resonance imaging score (WORMS). We performed linear regression, adjusting for age, sex, body mass index, physical activity, smoking status, alcohol use, KL score, number of anti-hypertensive medications, and number of nonsteroidal anti-inflammatory drugs.

RESULTS

Higher baseline DBP was associated with greater increases in global T2 (coefficient 0.22 (95% CI 0.09, 0.34), P = 0.004), global superficial layer T2 (coefficient 0.39 (95% CI 0.20, 0.58), P = 0.001), global contrast (coefficient 15.67 (95% CI 8.81, 22.53), P < 0.001), global entropy (coefficient 0.02 (95% CI 0.01, 0.03) P = 0.011), and global variance (coefficient 9.14 (95% CI 5.18, 13.09), P < 0.001). Compared with DBP, the associations of SBP with change in cartilage T2 parameters and WORMS subscores showed estimates of smaller magnitude.

CONCLUSION

Higher baseline DBP was associated with higher and more heterogenous cartilage T2 values over 48 months, indicating increased cartilage matrix degenerative changes.

[there any association of metabolic disturbances with joint destruction and pain?]

Osteoarthritis and type 2 diabetes mellitus represent two the most common chronic diseases. They possess many shared epidemiologic traits, have common risk factors, and embody heterogeneous multifactorial pathologies, which develop due to interaction of genetic an environmental factors. In addition, these diseases are often occurring in the same patient. In spite of the differences in clinical manifestation both diseases have similar disturbances of cellular metabolism, primarily associated with ATP production and utilization. The review discusses molecular mechanisms determining pathophysiological processes associated with glucose and lipid metabolism as well as the means aiming to alleviate the disturbances of energy metabolism as a new a therapeutic approach.

Multidisciplinary integrated approach for older adults with symptomatic osteoarthritis: SIMFER and SI-GUIDA Joint Position Statement

Multidisciplinary approach to osteoarthritis (OA) in older patients, whose functional decline is multifactorial and who present with multiple symptoms, has been long advocated, but it is still seldom implemented in daily practice. Therefore, further indications for the management of OA are eagerly awaited and should consider the specific clinical features of this population, including the presence of frailty and comorbidities. This clinical approach should be based both on well-grounded evidence and practical experience of experts in OA management. This manuscript comments the multidisciplinary integrated approach for OA management in the older population, according to the opinion of a multidisciplinary Panel of Experts. This project was developed by a Steering Committee, which consisted of three experts that were identified by the Italian Society of Physical and Rehabilitation Medicine (Società Italiana di Medicina Fisica e Riabilitativa, SIMFER) and the Italian Society for Unified and Interdisciplinary Management of Musculoskeletal Pain and Algodystrophy (Società Italiana per la Gestione Unificata e Interdisciplinare del Dolore muscolo-scheletrico e dell'Algodistrofia, SI-GUIDA). The Steering Committee identified key evidence on the management of OA in the older through systematic research in MEDLINE and EMBASE, selected the most relevant paper among those identified, and defined some questions concerning current unmet needs in the management of symptomatic OA in the older accordingly. The Panel discussed the identified evidence and questions during two meetings. The discussion was used to generate seven statements with relevance to clinical practice. In conclusion, older adults with symptomatic OA present multiple concomitant issues, including other diseases, marked pain, poly-pharmacy, and often poor psychological and/or socioeconomical status. According to the above-described evidence, it is crucial that the approach to those patients is multidisciplinary and based on the use of dedicated tools. A combination of exercise, mechanical support and properly selected analgesic treatment will greatly help the management of the OA patient, improving at the same time his/her quality of life.

Association of glucose homeostasis and metabolic syndrome with knee cartilage defects and cartilage volume in young adults

OBJECTIVE

To describe the associations of glucose homeostasis and metabolic syndrome (MetS) measures with knee cartilage defects and cartilage volume in young adults.

METHODS

Fasting blood biochemistry, waist circumference and blood pressure measures were collected 4-5 years prior to knee magnetic resonance imaging (MRI) scans. Blood measures included levels of glucose, insulin, triglyceride and high-density lipoprotein cholesterol (HDL-C). Homeostatic model assessment 2-insulin resistance (HOMA2-IR), HOMA2-beta cell function (HOMA2-β), HOMA2-insulin sensitivity (HOMA-S) and MetS were calculated or defined. Knee cartilage defects and cartilage volume were measured from MRI scans. Data were analysed using log binomial or linear regressions.

RESULTS

Among 328 participants (47.3% were females, aged 26-36 years at baseline), 40 (12.7%) had hyperglycaemia and 21 (6.7%) had MetS. Glucose homeostasis measures (except fasting glucose) were associated with tibiofemoral cartilage defects (fasting insulin: relative risk (RR) 1.05, 95% confidence interval (CI) 1.01 to 1.08; HOMA2-IR: 1.44, 1.08 to 1.92; HOMA2-β: 2.59, 1.33 to 5.07; HOMA2-S: 0.36, 0.18 to 0.72), but not patellar cartilage defects. There were no associations between glucose homeostasis measures and knee cartilage volume. High waist circumference (RR 2.32, 95% CI 1.18 to 4.54) and low HDL-C (RR 1.99, 95% CI 1.08 to 3.69) were associated with tibiofemoral cartilage defects, but no other associations were observed between MetS or its components and cartilage defects or volume.

CONCLUSION

Insulin resistance, high waist circumference and low HDL-C were associated with higher risk of tibiofemoral cartilage defects, suggesting glucose homeostasis and some MetS components may affect early cartilage damage in young adults.

Dietary intake of fatty acids and antioxidants in relation to radiographic knee osteoarthritis: results from a case-control study

BACKGROUND

The present study aimed to investigate levels of nutrient intakes, including dietary antioxidant quality (DAQ) score, among Saudi females with and without knee osteoarthritis (OA). We also aimed to examine the relationship between nutrient intakes and knee OA severity.

METHODS

One hundred female participants with symptomatic primary knee OA were matched for age with 100 apparently healthy females and were sequentially recruited from the Orthopaedics Department, Faculty of Medicine, King Abdulaziz University Hospital, Saudi Arabia, in a case-control study design. Radiographic disease severity of OA was assessed by the Kellgren-Lawrence grading system. Symptomatic severity was evaluated according to the Western Ontario McMaster University Osteoarthritis scores. Dietary intake was assessed using a prevalidated food frequency questionnaire. The DAQ score was calculated considering the risk of an inadequate intake (<2/3 reference nutrient intake) for selenium, zinc, vitamins A, C and E.

RESULTS

A higher intake of saturated fatty acids [15.4 (0.3) as a mean (SD) percentage of energy supplied] and monounsaturated fatty acids [16.6 (0.2) as a percentage of energy supplied] than the recommendations was evident among the study population. OA patients consume less antioxidants than non-OA subjects as determined by their DAQ score [8.41 (0.1) versus 9.17 (0.1), P < 0.0001]. After adjusting for potential confounders, DAQ score, and monounsaturated and polyunsaturated fatty acids, most of the micronutrient intakes were found to be negatively associated with the prevalence of radiographic knee OA.

CONCLUSIONS

Dietary antioxidants could be implicated in the development and progression of knee OA. Modifying dietary fatty acids may be one way of reducing the development and subsequent burden of knee OA.

Diabetic hip arthropathy is associated with a higher prevalence of femoral head chondromalacia: a case-controlled study

INTRODUCTION

No previous studies have characterised hip joint disease in diabetic patients undergoing hip arthroscopy. The purpose of our study was to evaluate intra-articular hip pathology and surgical variables in patients with diabetes compared to matched, non-diabetic controls. We hypothesised that diabetic patients would demonstrate a higher prevalence and severity of hip chondral pathology.

METHODS

We retrospectively reviewed 795 consecutive hip arthroscopies performed by a single surgeon between 2010 and 2015. Patients ⩾18 years of age without a history of diabetes served as controls and were matched based on age, sex, body mass index, duration of symptoms, and operative side. Clinical symptoms, preoperative physical examination, and radiologic and intraoperative findings were assessed. The primary outcomes were the acetabular and femoral head chondromalacia index (CMI), calculated as the product of the Outerbridge chondromalacia grade and surface area (mm²*severity).

RESULTS

15 diabetic patients were matched to 137 non-diabetic controls. Diabetic patients demonstrated a higher prevalence of femoral head chondromalacia compared to controls both on magnetic resonance imaging (45.5% vs. 7.5%, p = 0.002) and during arthroscopy (100% vs. 75.9%, p = 0.042). Femoral head chondromalacia in diabetic patients had higher Outerbridge grade (2.4 vs. 2.0, p = 0.030) but similar CMI (513.0 vs. 416.4, p = 0.298) compared to controls.

DISCUSSION

Femoral head chondral pathology was more prevalent and of higher severity grade in diabetic patients. The prevalence, size, and severity of acetabular chondral disease were similar between diabetic and non-diabetic patients. Multivariate analysis demonstrated that diabetic status was independently associated with the presence of femoral head chondromalacia.

Association between metabolic syndrome and knee structural change on MRI

Objective

To examine the association of metabolic syndrome (MetS) and its components with knee cartilage volume loss and bone marrow lesion (BML) change.

Methods

Longitudinal data on 435 participants from a population-based cohort study were analysed. Blood pressure, glucose, triglycerides and high-density lipoprotein (HDL) were collected. MetS was defined based on the National Cholesterol Education Program–Adult Treatment Panel III criteria. MRI of the right knee was performed to measure cartilage volume and BML. Radiographic knee OA was assessed by X-ray and graded using the Altman atlas for osteophytes and joint space narrowing.

Results

Thirty-two percent of participants had MetS and 60% had radiographic knee OA. In multivariable analysis, the following were independently associated with medial tibial cartilage volume loss: MetS, β = −0.30%; central obesity, β = −0.26%; and low HDL, β = −0.25% per annum. MetS, hypertriglyceridaemia and low HDL were also associated with higher risk of BML size increase in the medial compartment (MetS: relative risk 1.72, 95% CI 1.22, 2.43; hypertriglyceridaemia: relative risk 1.43, 95% CI 1.01, 2.02; low HDL: relative risk 1.67, 95% CI 1.18, 2.36). After further adjustment for central obesity or BMI, MetS and low HDL remained statistically significant for medial tibial cartilage volume loss and BML size increase. The number of components of MetS correlated with greater cartilage volume loss and BML size increase (both P for trend <0.05). There were no statistically significant associations in the lateral compartment.

Conclusion

MetS and low HDL are associated with medial compartment cartilage volume loss and BML size increase, suggesting that targeting these factors has the potential to prevent or slow knee structural change.

Weight loss regimen in obese and overweight individuals is associated with reduced cartilage degeneration: 96-month data from the Osteoarthritis Initiative

PURPOSE

To investigate change in knee cartilage composition over 96 months in overweight and obese participants with constant weight compared to those with weight loss (WL), and to assess how different WL regimens are associated with these changes.

METHODS

We studied right knees of 760 participants (age 62.6 ± 9.0y; 465 females) with a baseline body mass index (BMI) >25 kg/m2 from the Osteoarthritis Initiative with mild to moderate or with risk factors for knee osteoarthritis. Participants losing weight (>5% of baseline BMI over 72 months; N = 380) were compared to controls with stable weight (SW, N = 380). Participants losing weight were categorized based on WL method (diet and exercise, diet only, exercise only) and compared to those with stable weight. Magnetic resonance imaging (MRI) at 3T was performed at baseline, 48- and 96-months. The association of WL and WL method with change in cartilage composition, measured with T2 mapping, was analyzed using mixed random effects models.

RESULTS

Compared to SW, WL was associated with a significantly slower increase in global (averaged over all compartments) cartilage T2 (adjusted mean difference of change in T2 ms/year [95% CI] between the groups: 0.24 [0.20, 0.41] ms/year; P < 0.001) and global deep layer cartilage T2 0.35 [0.20, 0.42] ms/year; P < 0.001), suggesting slower cartilage deterioration. Compared to the SW group, slower increases in global T2 were observed in the diet and diet and exercise groups, but not in the exercise only group (P = 0.042, P = 0.003 and P = 0.85, respectively).

CONCLUSION

Our results suggest that WL may slow knee cartilage degeneration over 96 months, and that these potential benefits may differ by method of WL.

5-Azacytidine and Resveratrol Enhance Chondrogenic Differentiation of Metabolic Syndrome-Derived Mesenchymal Stem Cells by Modulating Autophagy

Recently, metabolic syndrome (MS) has gained attention in human and animal metabolic medicine. Insulin resistance, inflammation, hyperleptinemia, and hyperinsulinemia are critical to its definition. MS is a complex cluster of metabolic risk factors that together exert a wide range of effects on multiple organs, tissues, and cells in the body. Adipose stem cells (ASCs) are multipotent stem cell population residing within the adipose tissue that is inflamed during MS. Studies have indicated that these cells lose their stemness and multipotency during MS, which strongly reduces their therapeutic potential. They suffer from oxidative stress, apoptosis, and mitochondrial deterioration. Thus, the aim of this study was to rejuvenate these cells in vitro in order to improve their chondrogenic differentiation effectiveness. Pharmacotherapy of ASCs was based on resveratrol and 5-azacytidine pretreatment. We evaluated whether those substances are able to reverse aged phenotype of metabolic syndrome-derived ASCs and improve their chondrogenic differentiation at its early stage using immunofluorescence, transmission and scanning electron microscopy, real-time PCR, and flow cytometry. Obtained results indicated that 5-azacytidine and resveratrol modulated mitochondrial dynamics, autophagy, and ER stress, leading to the enhancement of chondrogenesis in metabolically impaired ASCs. Therefore, pretreatment of these cells with 5-azacytidine and resveratrol may become a necessary intervention before clinical application of these cells in order to strengthen their multipotency and therapeutic potential.

MRI T2 and T1ρ relaxation in patients at risk for knee osteoarthritis: a systematic review and meta-analysis

Background

Magnetic resonance imaging (MRI) T2 and T1ρ relaxation are increasingly being proposed as imaging biomarkers potentially capable of detecting biochemical changes in articular cartilage before structural changes are evident. We aimed to: 1) summarize MRI methods of published studies investigating T2 and T1ρ relaxation time in participants at risk for but without radiographic knee OA; and 2) compare T2 and T1ρ relaxation between participants at-risk for knee OA and healthy controls.

Methods

We conducted a systematic review of studies reporting T2 and T1ρ relaxation data that included both participants at risk for knee OA and healthy controls. Participant characteristics, MRI methodology, and T1ρ and T2 relaxation data were extracted. Standardized mean differences (SMDs) were calculated within each study. Pooled effect sizes were then calculated for six commonly segmented knee compartments.

Results

55 articles met eligibility criteria. There was considerable variability between scanners, coils, software, scanning protocols, pulse sequences, and post-processing. Moderate risk of bias due to lack of blinding was common. Pooled effect sizes indicated participants at risk for knee OA had lengthened T2 relaxation time in all compartments (SMDs from 0.33 to 0.74; p < 0.01) and lengthened T1ρ relaxation time in the femoral compartments (SMD from 0.35 to 0.40; p < 0.001).

Conclusions

T2 and T1ρ relaxation distinguish participants at risk for knee OA from healthy controls. Greater standardization of MRI methods is both warranted and required for progress towards biomarker validation.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2547-7) contains supplementary material, which is available to authorized users.

3D grating-based X-ray phase-contrast computed tomography for high-resolution quantitative assessment of cartilage: An experimental feasibility study with 3T MRI, 7T MRI and biomechanical correlation

Objective

Aim of this study was, to demonstrate the feasibility of high-resolution grating-based X-ray phase-contrast computed tomography (PCCT) for quantitative assessment of cartilage.

Materials and methods

In an experimental setup, 12 osteochondral samples were harvested from n = 6 bovine knees (n = 2 each). From each knee, one cartilage sample was degraded using 2.5% Trypsin. In addition to PCCT and biomechanical cartilage stiffness measurements, 3T and 7T MRI was performed including MSME SE T2 and ME GE T2* mapping sequences for relaxationtime measurements. Paired t-tests and receiver operating characteristics (ROC) curves were used for statistical analyses.

Results

PCCT provided high-resolution images for improved morphological cartilage evaluation as compared to 3T and 7T MRI. Quantitative analyses revealed significant differences between the superficial and the deep cartilage layer for T2 mapping as well as for PCCT (P<0.05). No significant difference was detected for PCCT between healthy and degraded samples (P>0.05). MRI and stiffness measurements showed significant differences between healthy and degraded osteochondral samples. Accuracy in the prediction of cartilage degradation was excellent for MRI and biomechanical analyses.

Conclusion

In conclusion, high-resolution grating-based X-ray PCCT cartilage imaging is feasible. In addition to MRI and biomechanical analyses it provides complementary, water content independent, information for improved morphological and quantitative characterization of articular cartilage ultrastructure.

The Metabolome and Osteoarthritis: Possible Contributions to Symptoms and Pathology

Osteoarthritis (OA) is a progressive, deteriorative disease of articular joints. Although traditionally viewed as a local pathology, biomarker exploration has shown that systemic changes can be observed. These include changes to cytokines, microRNAs, and more recently, metabolites. The metabolome is the set of metabolites within a biological sample and includes circulating amino acids, lipids, and sugar moieties. Recent studies suggest that metabolites in the synovial fluid and blood could be used as biomarkers for OA incidence, prognosis, and response to therapy. However, based on clinical, demographic, and anthropometric factors, the local synovial joint and circulating metabolomes may be patient specific, with select subsets of metabolites contributing to OA disease. This review explores the contribution of the local and systemic metabolite changes to OA, and their potential impact on OA symptoms and disease pathogenesis.

Association between serum magnesium concentration and metabolic syndrome, diabetes, hypertension and hyperuricaemia in knee osteoarthritis: a cross-sectional study in Hunan Province, China

OBJECTIVES

To examine the associations between serum magnesium (Mg) concentration with the prevalence of metabolic syndrome (MetS), diabetes mellitus (DM), hypertension (HP) and hyperuricaemia (HU) in patients with radiographic knee osteoarthritis (OA).

METHODS

The present study was conducted at the Health Management Center of Xiangya Hospital. Radiographic OA was evaluated for patients aged over 40 years with basic characteristics and blood biochemical assessment. Serum Mg concentration was measured using the chemiluminescence method. MetS, DM, HP and HU were diagnosed based on standard protocols. The associations between serum Mg concentration with MetS, DM, HP and HU were evaluated by conducting multivariable adjusted logistic regression.

RESULTS

A total of 962 patients with radiographic knee OA were included. Compared with the lowest quintile, the multivariable adjusted ORs and related 95% CIs of DM were 0.40 (95% CI 0.23 to 0.70, p=0.001), 0.33 (95% CI 0.18 to 0.60, p<0.001), 0.27 (95% CI 0.14 to 0.52, p<0.001) and 0.22 (95% CI 0.11 to 0.44, p<0.001) in the second, third, fourth and highest quintiles of serum Mg, respectively (p for trend <0.001); the multivariable adjusted ORs of HU were 0.33 (95% CI 0.19 to 0.59, p<0.001), 0.52 (95% CI 0.30 to 0.91, p=0.022) and 0.39 (95% CI 0.22 to 0.70, p=0.001) in the third, fourth and highest quintiles of serum Mg, respectively (p for trend <0.001); and the multivariable adjusted ORs of MetS were 0.59 (95% CI 0.36 to 0.94, p=0.027) in the second and 0.56 (95% CI 0.34 to 0.93, p=0.024) in the highest quintiles of serum Mg. However, the inverse association between serum Mg and the prevalence of MetS was non-linear (p for trend=0.067). There was no significant association between serum Mg and HP in patients with OA.

CONCLUSIONS

The serum Mg concentration was inversely associated with the prevalence of MetS, DM and HU in patients with radiographic knee OA.

LEVEL OF EVIDENCE

Level III, cross-sectional study.

Osteoarthritis and the Mediterranean Diet: A Systematic Review

Osteoarthritis (OA) affects 240 million people globally. Few studies have examined the links between osteoarthritis and the Mediterranean diet (MD). The aim of this paper was to systematically review and analyze the epidemiological evidence in humans on the MD and its association with OA. A systematic search of EMBASE identified three studies that explored the association between MD and OA. Two of them were cross-sectional and the third one was a 16-week randomized clinical trial. Prisma declaration was followed to carry out this review. These studies described a positive association between a higher adherence to a MD and the quality of life of participants suffering OA. The prevalence of OA was lower in participants with a higher adherence to a Mediterranean diet. Biomarkers of inflammation and cartilage degradation related to OA were also analyzed and significant differences were detected only for IL1-α, which decreased in the MD group. Exploring the relationship between MD and OA is complex, moreover, the limited evidence and methodological differences in such studies makes it difficult to compare results. In conclusion, the three studies included in this systematic review demonstrated some relation between osteoarthritis and a Mediterranean diet. However, prospective and longer interventions are required to evaluate the long-term efficacy of the Mediterranean diet to improve symptomatology and preventing osteoarthritis.

Longitudinal changes in subchondral bone structure as assessed with MRI are associated with functional outcome after high tibial osteotomy

OBJECTIVES

The primary objective of this study was to evaluate the effects of high tibial osteotomy (HTO) on subchondral bone structure assessed with magnetic resonance (MR)-based trabecular bone imaging and the correlations of these effects with functional outcome and clinical symptoms.

METHODS

Patients with varus malalignment (6.2±2.2°) and without a history of knee surgery (n=22; 3 women; 48.7±10.3 years) were included into this prospective study. 1.5T MR imaging was performed before and on average 1.5 years after HTO (amount of correction 4.7±2.5°) and histomorphometric parameters of the trabecular bone were calculated for the medial/ lateral tibia and femur. Functional outcome was assessed with validated scores focusing on sports activity including the Lysholm Score, Tegner Activity Scale and the adapted Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Score.

RESULTS

Apparent trabecular number significantly decreased in all compartments of the tibiofemoral joint when comparing values before and on average 1.5 years after HTO (P<0.05 for all). Decrease in apparent trabecular number was significantly higher within the medial tibia compared to the lateral compartment (mean difference -0.24 mm^-1 (95% confidence interval (CI): -0.33, -0.14 mm^-1); P<0.001). Apparent trabecular bone thickness significantly increased within 1.5 years after HTO in the lateral femur (P=0.002) and tibia (P <0.001). The Lysholm Score and Tegner Scale demonstrated an improvement of functional outcome, and the adapted WOMAC demonstrated an improvement of pain, stiffness and physical function within 1.5 years after HTO (P<0.01), with the improvement of WOMAC correlating significantly with changes in trabecular bone thickness within the medial tibia (r= -0.48; P=0.01).

CONCLUSION

These findings indicate a reversal of the previous subchondral bone alterations in patients with varus malalignment after undergoing HTO, while pronounced subchondral changes were associated with a better functional outcome.

LEVEL OF EVIDENCE

3.

Conservatively treated knee injury is associated with knee cartilage matrix degeneration measured with MRI-based T2 relaxation times: data from the osteoarthritis initiative

OBJECTIVE

To investigate the association of cartilage degeneration with previous knee injuries not undergoing surgery, determined by morphologic and quantitative 3-T magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We performed a nested cross-sectional study of right knee MRIs from participants in the Osteoarthritis Initiative (OAI) aged 45-79 with baseline Kellgren-Lawrence score of 0-2. Cases were 142 right knees of patients with self-reported history of injury limiting the ability to walk for at least 2 days. Controls were 426 right knees without history of injury, frequency-matched to cases on age, BMI, gender, KL scores and race (1:3 ratio). Cases and controls were compared using covariate-adjusted linear regression analysis, with the outcomes of region-specific T2 mean, laminar analysis and heterogeneity measured by texture analysis to investigate early cartilage matrix abnormalities and the Whole-Organ Magnetic Resonance Imaging Score (WORMS) to investigate morphologic knee lesions.

RESULTS

Compared to control subjects, we found significantly higher mean T2 values in the injury [lateral tibia (28.10 ms vs. 29.11 ms, p = 0.001), medial tibia (29.70 ms vs. 30.40 ms, p = 0.014) and global knee cartilage (32.73 ms vs. 33.29 ms, p = 0.005)]. Injury subjects also had more heterogeneous cartilage as measured by GLCM texture contrast, variance and entropy (p < 0.05 in 14 out of 18 texture parameters). WORMS gradings were not significantly different between the two groups (p > 0.05).

CONCLUSION

A history of knee injury not treated surgically is associated with higher and more heterogeneous T2 values, but not with morphologic knee abnormalities. Our findings suggest that significant, conservatively treated knee injuries are associated with permanent cartilage matrix abnormalities.

Association of weight change with progression of meniscal intrasubstance degeneration over 48 months: Data from the Osteoarthritis Initiative

OBJECTIVES

To investigate the association of weight change over 48 months with progression of meniscal intrasubstance degeneration (MID).

METHODS

We studied 487 subjects with MID at baseline and after 48 months using 3-T MRI with the same protocol (FSE sequences with and without fat suppression). These participants lost weight (≥3%, n = 141), had moderate weight gain (3-10%, n = 77), substantial weight gain (>10%, n = 15) or maintained stable weight (n = 254). Progression of MID to a meniscal tear was assessed using the WORMS grading system and compared among weight change groups using logistic regression. ANOVA and chi-square tests were used to study the differences in subjects' characteristics.

RESULTS

Progression of MID increased from weight loss to substantial weight gain (p < 0.001) and was significantly more likely with both moderate weight gain (odds ratio [OR], 4.9; 95% confidence interval [CI] 2.4-8.9) and substantial weight gain (OR, 9.5; 95% CI 3.2-28.5) compared to stable weight. Results were similar in both menisci for moderate weight gain (medial: OR, 6.8; 95% CI 3.5-11.3; lateral: OR, 2.6; 95% CI 1.1-6.6) and substantial weight gain (medial: OR, 21.0; 95% CI 5.1-80.7; lateral: OR, 9.7; 95% CI 0.95-100.2).

CONCLUSION

Weight gain is associated with an increased likelihood that meniscal intrasubstance degeneration will progress with the risk increasing with greater weight gain.

KEY POINTS

• Subjects who gained weight were more likely to develop meniscal tears. • Greater amount of weight gain was associated with an increasing likelihood of progression. • Prevention of weight gain has health benefits for the meniscus.

The role of Mediterranean diet and its components on the progress of osteoarthritis

Osteoarthritis is the most common, incurable joint disease. The rapid pace of the disease has adverse consequences in the quality of patient's life, while affecting healthcare systems. The research interest is focused on cost-effective and without side-effects methods to reduce the symptoms and improve the quality of life. Several dietary factors have been linked to the health of cartilage tissue, inflammatory processes and the progress of osteoarthritis. Mediterranean diet (MD) is a dietary pattern that was adopted by people living around the Mediterranean sea. This term first appeared in 1950, by Ancel Keys. It's characterized by high consumption of vegetables, unprocessed grains, fruits, legumes, seeds, modest consumption of fish and poultry and olive oil is the principal fat source. Emerged data emphasize the beneficial effects of MD against chronic inflammation, metabolic complications and chronic diseases. There are few studies investigating the effect of MD against osteoarthritis, but apparent evidence is encouraging, this highlights the need for further research of the relationship between MD and osteoarthritis. The purpose of this work is a literature review between the effect of MD and its components and the progress of osteoarthritis.

Meniscal extrusion and bone marrow lesions are associated with incident and progressive knee osteoarthritis

OBJECTIVE

Whether meniscal extrusion and bone marrow lesions (BMLs) are independently associated with the risk of knee osteoarthritis (OA) is unknown.

METHODS

Data was extracted from the Osteoarthritis Initiative (OAI) cohort. Participants were grouped according to the absence (Kellgren-Lawrence (KL) grade ≤ 1, n = 2120) or presence (KL ≥ 2, n = 2249) of radiographic OA (ROA). Baseline meniscal extrusion and tibial BMLs were assessed. Tibial plateau cartilage volume was assessed at baseline and 72 months, while radiographic disease was assessed at baseline and 48 months. Total knee replacement (TKR) was assessed at 72 months.

RESULTS

In those with ROA, the presence of a baseline meniscal extrusion (independent of BMLs) was associated with accelerated cartilage volume loss (medial tibia: -2.1%/annum vs -1.5%; lateral: -2.6%/annum vs -1.6%; both P < 0.001), progressive ROA and TKR (Odds ratio (OR) range 1.4-1.8; 95% CI range 1.1-2.9). The presence of a baseline BML was associated with accelerated cartilage volume loss (medial tibia: -2.1%/annum vs -1.6%; lateral: -1.9%/annum vs -1.6%; P ≤ 0.02), progressive ROA and joint replacement (OR range 1.5-2.4; 95% CI range 1.1-3.4). In those with no ROA, a baseline medial meniscal extrusion was associated with accelerated cartilage volume loss (medial tibia: -2.1%/annum vs -1.2%, P < 0.001), and a baseline medial BML with incident ROA (OR 1.7, 95% CI 1.1 to 2.9).

CONCLUSIONS

The presence of baseline meniscal extrusion and BMLs are associated with incident and progressive knee of each other (OA) and represent important structural targets for the treatment and prevention of knee OA.

Association of diabetes mellitus and biochemical knee cartilage composition assessed by T2 relaxation time measurements: Data from the osteoarthritis initiative

PURPOSE

To investigate the association of the presence and severity of diabetes mellitus (DM) with articular cartilage composition, using magnetic resonance imaging (MRI)-based T₂ relaxation time measurements, and structural knee abnormalities.

MATERIALS AND METHODS

In the Osteoarthritis Initiative 208, participants with DM (age 63.0 ± 8.9 years; 111 females) and risk factors for osteoarthritis (OA) or mild radiographic tibiofemoral OA (Kellgren-Lawrence [KL] grade ≤2) were identified and group-matched with 208 controls without DM (age 63.3 ± 9.1 years; 111 females). Subjects with diabetes-related renal or ophthalmological complications or insulin treatment at baseline (n = 50) were defined as severe DM. 3T MR images of the right knee were assessed for articular cartilage T₂ , including texture and laminar analyses derived from the patella, medial, and lateral femur and tibia and for structural abnormalities using the modified whole-organ magnetic resonance imaging score (WORMS). Clustered linear regression analyses were used to assess associations of DM with MRI findings.

RESULTS

DM subjects had significantly higher cartilage T₂ in the patella (mean difference 0.92 msec [95% confidence interval (CI) 0.79, 1.06]; P = 0.001) and medial femur (mean difference 0.36 msec [95% CI 0.27, 0.81]; P = 0.006) compared to controls. Averaged over all compartments, DM subjects showed significantly higher texture parameters (variance, P = 0.001; contrast, P = 0.002; entropy, P < 0.001). Subjects with severe DM additionally showed higher T₂ in the medial tibial deep and superficial layers (P = 0.011 and P = 0.041) compared to controls. No significant differences in cartilage, meniscus, and overall WORMS were found between the groups (P > 0.05).

CONCLUSION

In comparison to nondiabetic controls, cartilage in DM subjects showed higher and more heterogeneous cartilage T₂ values, indicating increased articular cartilage degeneration. This affected even more compartments in subjects with severe DM.

LEVEL OF EVIDENCE

2 Technical Efficacy: 5 J. Magn. Reson. Imaging 2018;47:380-390.

Long term type 1 diabetes is associated with hand pain, disability and stiffness but not with structural hand osteoarthritis features - The Dialong hand study

OBJECTIVE

To explore whether having long-term type 1 diabetes (>45 years) is associated with a higher prevalence of radiographic hand OA, erosive hand OA and increased hand pain, disability and stiffness.

METHODS

In total N = 96 persons with type 1 diabetes diagnosed before 1970 were included (mean [SD] age: 62.2 [7.4], mean [SD] HbA1c: 7.43 [0.80] and N = 49 [51%] men). Regular measurements of their HbA1c were obtained till 2015. We included N = 69 healthy controls without any diabetes (mean [SD] age: 63.0 [7.0], mean [SD] HbA1c: 5.41 [0.32], N = 29 [42%] men). The groups were compared for radiographic hand OA (Kellgren-Lawrence grade ≥2 in ≥1 joint) and erosive hand OA (central erosions in ≥1 joint), Australian/Canadian index (AUSCAN) for hand pain, disability and stiffness using regression analyses adjusted for age, sex, educational level and waist circumference.

RESULTS

We found no associations between having long term type 1 diabetes and more prevalent radiographic hand OA (OR = 0.83, 95% CI = 0.38-1.81). We found a trend towards higher prevalence of erosive hand OA in diabetes patients (OR = 2.96, 95% CI = 0.82-10.64). Strong and consistent associations were observed between long term type 1 diabetes and increased hand pain (B = 2.78, 95% CI = 1.65-3.91), disability (B = 5.30, 95% CI = 3.48-7.12) and stiffness (B = 2.00, 95% CI = 1.33-2.67). These associations were particularly strong for women and participants below the median age of 61 years.

CONCLUSION

Long-term type 1 diabetes was not associated with radiographic hand OA, but was strongly associated with hand pain, disability and stiffness. The association between diabetes and erosive hand OA warrants further investigation.

Is Weight Loss Associated with Less Progression of Changes in Knee Articular Cartilage among Obese and Overweight Patients as Assessed with MR Imaging over 48 Months? Data from the Osteoarthritis Initiative

Purpose To investigate the association of weight loss with progression of cartilage changes at magnetic resonance (MR) imaging over 48 months in overweight and obese participants compared with participants of stable weight. Materials and Methods The institutional review boards of the four participating centers approved this HIPAA-compliant study. Included were (a) 640 participants (mean age, 62.9 years ± 9.1 [standard deviation]; 398 women) who were overweight or obese (body mass index cutpoints of 25 and 30 kg/m², respectively) from the Osteoarthritis Initiative, with risk factors for osteoarthritis or mild to moderate radiographic findings of osteoarthritis, categorized into groups with (a) weight loss of more than 10% (n = 82), (b) weight loss of 5%-10% (n = 238), or (c) stable weight (n = 320) over 48 months. Participants were frequency-matched for age, sex, baseline body mass index, and Kellgren-Lawrence score. Two radiologists assessed cartilage and meniscus defects on right knee 3-T MR images at baseline and 48 months by using the modified Whole-Organ Magnetic Resonance Imaging Score (WORMS). Progression of the subscores was compared between the weight loss groups by using multivariable logistic regression models. Results Over 48 months, adjusted mean increase of cartilage WORMS was significantly smaller in the 5%-10% weight loss group (1.6; 95% confidence interval [CI]: 1.3, 1.9; P = .002) and even smaller in the group with more than 10% weight loss (1.0; 95% CI: 0.6, 1.4; P = .001) when compared with the stable weight group (2.3; 95% CI: 2.0, 2.7). Moreover, percentage of weight change was significantly associated with increase in cartilage WORMS (β = 0.2; 95% CI: 0.02, 0.4; P = .007). Conclusion Participants who lost weight over 48 months showed significantly lower cartilage degeneration, as assessed with MR imaging; rates of progression were lower with greater weight loss. ^© RSNA, 2017.

Effect of a Mediterranean Type Diet on Inflammatory and Cartilage Degradation Biomarkers in Patients with Osteoarthritis

OBJECTIVES

To investigate the effects of a Mediterranean type diet on patients with osteoarthritis (OA).

PARTICIPANTS

Ninety-nine volunteers with OA (aged 31 - 90 years) completed the study (83% female).

SETTING

Southeast of England, UK.

DESIGN

Participants were randomly allocated to the dietary intervention (DIET, n = 50) or control (CON, n = 49). The DIET group were asked to follow a Mediterranean type diet for 16 weeks whereas the CON group were asked to follow their normal diet.

MEASUREMENTS

All participants completed an Arthritis Impact Measurement Scale (AIMS2) pre-, mid- and post- study period. A subset of participants attended a clinic at the start and end of the study for assessment of joint range of motion, ROM (DIET = 33, CON = 28), and to provide blood samples (DIET = 29, CON = 25) for biomarker analysis (including serum cartilage oligomeric matrix protein (sCOMP) (a marker of cartilage degradation) and a panel of other relevant biomarkers including pro- and anti-inflammatory cytokines).

RESULTS

There were no differences between groups in the response of any AIMS2 components and most biomarkers (p > 0.05), except the pro-inflammatory cytokine IL-1α, which decreased in the DIET group (~47%, p = 0.010). sCOMP decreased in the DIET group by 1 U/L (~8%, p = 0.014). There was a significant improvement in knee flexion and hip rotation ROM in the DIET group (p < 0.05).

CONCLUSIONS

The average reduction in sCOMP in the DIET group (1 U/L) represents a meaningful change, but the longer term effects require further study.

Prestructural cartilage assessment using MRI

Cartilage loss is irreversible, and to date, no effective pharmacotherapies are available to protect or regenerate cartilage. Quantitative prestructural/compositional MR imaging techniques have been developed to characterize the cartilage matrix quality at a stage where abnormal findings are early and potentially reversible, allowing intervention to halt disease progression. The goal of this article is to critically review currently available technologies, present the basic concept behind these techniques, but also to investigate their suitability as imaging biomarkers including their validity, reproducibility, risk prediction and monitoring of therapy. Moreover, we highlighted important clinical applications. This review article focuses on the currently most relevant and clinically applicable technologies, such as T2 mapping, T2*, T1ρ, delayed gadolinium enhanced MRI of cartilage (dGEMRIC), sodium imaging and glycosaminoglycan chemical exchange saturation transfer (gagCEST). To date, most information is available for T2 and T1ρ mapping. dGEMRIC has also been used in multiple clinical studies, although it requires Gd contrast administration. Sodium imaging and gagCEST are promising technologies but are dependent on high field strength and sophisticated software and hardware.

LEVEL OF EVIDENCE

5 J. Magn. Reson. Imaging 2017;45:949-965.

Changes in Cartilage and Tendon Composition of Patients With Type I Diabetes Mellitus: Identification by Quantitative Sodium Magnetic Resonance Imaging at 7 T

OBJECTIVE

The aim of this study was to investigate possible biochemical alterations in tendons and cartilage caused by type 1 diabetes mellitus (DM1), using quantitative in vivo 7 T sodium magnetic resonance (MR) imaging.

MATERIALS AND METHODS

The institutional review board approved this prospective study, and written informed consent was obtained. Eight DM1 patients with no history of knee trauma and 9 healthy age- and weight-matched volunteers were examined at 7 T using dedicated knee coils.All participants underwent morphological and sodium MR imaging. Region-of-interest analysis was performed manually for the non-weight-bearing area of the femoral condyle cartilage and for the patella tendon. Two readers read the image data sets independently, twice, for intrareader and interreader agreement. Normalized mean sodium signal intensity (NMSI) values were compared between patients and volunteers for each reader using analysis of variance.

RESULTS

On morphological images, cartilage in the non-weight-bearing area and the patellar tendon was intact in all patients. On sodium MR imaging, bivariate analysis of variance showed significantly lower mean NMSI values in the cartilage (P = 0.008) and significantly higher values in the tendons (P = 0.025) of patients compared with those of volunteers.

CONCLUSION

Our study showed significantly different NMSI values between DM1 patients and matched volunteers. Differences observed in the cartilage and tendon might be associated with a DM1-related alteration of biochemical composition that occurs before it can be visualized on morphological MR sequences.

Clinical settings in knee osteoarthritis: Pathophysiology guides treatment

Osteoarthritis (OA) is the most common chronic joint disorder and its prevalence increases rapidly during midlife. Complex interactions of genetic alterations, sex hormone deficit, and aging with mechanical factors and systemic inflammation-associated metabolic syndrome lead to joint damage. Thus, the expression of a clinical phenotype in the early stages of OA relies on the main underlying pathway and predominant joint tissue involved at a given time. Moreover, OA often coexists with other morbidities in the same patient, which in turn condition the OA process. In this scenario, an appropriate identification of clinical phenotypes, especially in the early stages of the disease, may optimize the design of individualized treatments in OA. An ESCEO-EUGMS (European Union Geriatric Medicine Society) working group has recently suggested possible patient profiles in OA. Hereby, we propose the existence of 4 clinical phenotypes - biomechanical, osteoporotic, metabolic and inflammatory - whose characterization would help to properly stratify patients with OA in clinical trials or studies. Further research in this field is warranted.

Clinical Factors, Disease Parameters, and Molecular Therapies Affecting Osseointegration of Orthopedic Implants

Total hip and knee arthroplasty are effective interventions for management of end-stage arthritis. Indeed, about 7 million Americans are currently living with artificial hip and knee joints. The majority of these individuals, however, will outlive their implants and require revision surgeries, mostly due to poor implant osseointegration and aseptic loosening. Revisions are potentially avoidable with better management of patient-related risk factors that affect the osseointegration of orthopedic implants. In this review, we summarize the published clinical literature on the role of demographics, biologic factors, comorbidities, medications and aseptic loosening risk. We focus on several systemic and local factors that are particularly relevant to implant osseointegration. Examples include physiological and molecular processes that are linked to hyperglycemia, oxidative stress, metabolic syndrome and dyslipidemia. We discuss how orthopedic implant osseointegration can be affected by a number of molecular therapies that are antiresorptive or bone anabolic (i.e. calcium, vitamin D, bisphosphonates, calcitonin, strontium, hormone replacement therapy, selective estrogen-receptor modulators).

Association of urinary metabolites with radiographic progression of knee osteoarthritis in overweight and obese adults: an exploratory study

INTRODUCTION

Metabolic factors may contribute to osteoarthritis (OA). This study employed metabolomics analyses to determine if differences in metabolite profiles could distinguish people with knee OA who exhibited radiographic progression.

METHODS

Urine samples obtained at baseline and 18 months from overweight and obese adults in the Intensive Diet and Exercise for Arthritis (IDEA) trial were selected from two subgroups (n = 22 each) for metabolomics analysis: a group that exhibited radiographic progression (≥0.7 mm decrease in joint space width, JSW) and an age, gender, and body mass index (BMI) matched group who did not progress (≤0.35 mm decrease in JSW). Multivariate analysis methods, including orthogonal partial least square discriminate analysis, were used to identify metabolite profiles that separated progressors and non-progressors. Plasma levels of IL-6 and C-reactive protein (CRP) were evaluated as inflammatory markers.

RESULTS

Multivariate analysis of the binned metabolomics data distinguished progressors from non-progressors. Library matching revealed that glycolate, hippurate, and trigonelline were among the important metabolites for distinguishing progressors from non-progressors at baseline whereas alanine, N,N-dimethylglycine, glycolate, hippurate, histidine, and trigonelline, were among the metabolites that were important for the discrimination at 18 months. In non-progressors, IL-6 decreased from baseline to 18 months while IL-6 was unchanged in progressors; the change over time in IL-6 was significantly different between groups.

CONCLUSION

These findings support a role for metabolic factors in the progression of knee OA and suggest that measurement of metabolites could be useful to predict progression. Further investigation in a larger sample that would include targeted investigation of specific metabolites is warranted.

Progression of cartilage degeneration and clinical symptoms in obese and overweight individuals is dependent on the amount of weight loss: 48-month data from the Osteoarthritis Initiative

OBJECTIVE

To investigate compositional cartilage changes measured with 3T MRI-based T2 values over 48 months in overweight and obese individuals with different degrees of weight loss (WL) and to study whether WL slows knee cartilage degeneration and symptom worsening.

DESIGN

We studied participants from the Osteoarthritis Initiative with risk factors or radiographic evidence of mild to moderate knee osteoarthritis with a baseline BMI ≥25 kg/m(2). We selected subjects who over 48 months lost a, moderate (BMI change, 5-10%WL, n = 180) or large amount of weight (≥10%WL, n = 78) and frequency-matched these to individuals with stable weight (<3%, n = 258). Right knee cartilage T2 maps of all compartments and grey-level co-occurrence matrix (GLCM) texture analyses were evaluated and associations with WL and clinical symptoms (WOMAC subscales for pain, stiffness and disability) were assessed using multivariable regression models.

RESULTS

The amount of weight change was significantly associated with change in cartilage T2 of the medial tibia (β 0.9 ms, 95% CI 0.4 to 1.1, P = 0.001). Increase of T2 in the medial tibia was significantly associated with increase in WOMAC pain (β 0.5 ms, 95% CI 0.2 to 0.6, P = 0.02) and disability (β 0.03 ms, 95% CI 0.003 to 0.05, P = 0.03). GLCM contrast and variance over all compartments showed significantly less progression in the >10%WL group compared to the stable weight group (both comparisons, P = 0.04).

CONCLUSIONS

WL over 48 months is associated with slowed knee cartilage degeneration and improved knee symptoms.

Can Signal Abnormalities Detected with MR Imaging in Knee Articular Cartilage Be Used to Predict Development of Morphologic Cartilage Defects? 48-Month Data from the Osteoarthritis Initiative

Purpose To determine the incidence with which morphologic articular cartilage defects develop over 48 months in cartilage with signal abnormalities at baseline magnetic resonance (MR) imaging in comparison with the incidence in articular cartilage without signal abnormalities at baseline. Materials and Methods The institutional review boards of all participating centers approved this HIPAA-compliant study. Right knees of 90 subjects from the Osteoarthritis Initiative (mean age, 55 years ± 8 [standard deviation]; 51% women) with cartilage signal abnormalities but without morphologic cartilage defects at 3.0-T MR imaging and without radiographic osteoarthritis (Kellgren-Lawrence score, 0-1) were frequency matched for age, sex, Kellgren-Lawrence score, and body mass index with right knees in 90 subjects without any signal abnormalities or morphologic defects in the articular cartilage (mean age, 54 years ± 5; 51% women). Individual signal abnormalities (n = 126) on intermediate-weighted fast spin-echo MR images were categorized into four subgrades: subgrade A, hypointense; subgrade B, inhomogeneous; subgrade C, hyperintense; and subgrade D, hyperintense with swelling. The development of morphologic articular cartilage defects (Whole-Organ MR Imaging Score ≥2) at 48 months was analyzed on a compartment level and was compared between groups by using generalized estimating equation logistic regression models. Results Cartilage signal abnormalities were more frequent in the patellofemoral joint than in the tibiofemoral joint (59.5% vs 39.5%). Subgrade A was seen more frequently than were subgrades C and D (36% vs 22%). Incidence of morphologic cartilage defects at 48 months was 57% in cartilage with baseline signal abnormalities, while only 4% of compartments without baseline signal abnormalities developed morphologic defects at 48 months (all compartments combined and each compartment separately, P < .01). The development of morphologic defects was not significantly more likely in any of the subgrades (P = .98) and was significantly associated with progression of bone marrow abnormalities (P = .002). Conclusion Knee cartilage signal abnormalities detected with MR imaging are precursors of morphologic defects with osteoarthritis and may serve as imaging biomarkers with which to assess risk for cartilage degeneration. (©) RSNA, 2016.

Quantitative relationship of thigh adipose tissue with pain, radiographic status, and progression of knee osteoarthritis: longitudinal findings from the osteoarthritis initiative

OBJECTIVE

The aim of this study was to explore the relationship of thigh subcutaneous fat (SCF) and intermuscular fat (IMF) content with knee osteoarthritis (KOA) cross-sectionally and longitudinally, using quantitative magnetic resonance imaging. Specifically, we examined relationships with frequent knee pain, various radiographic strata, and structural progression status of KOA.

MATERIALS AND METHODS

Subjects who showed between-knee discordance of frequent versus no pain (n = 48), osteophyte versus no radiographic KOA (n = 55), and radiographic joint space narrowing versus no joint space narrowing (n = 44) were selected from the Osteoarthritis Initiative. Knees with structural progression of KOA (n = 23) were compared with knees without progression. Axial thigh magnetic resonance images were used to determine IMF and SCF. Differences between knees and between baseline and 2-year follow-up were examined using paired t tests.

RESULTS

Women displayed similar amounts of IMF, but twice the SCF of men. Limbs of women with frequently painful knees had statistically significant greater IMF areas (+4.2%; P = 0.05) than contralateral pain-free limbs did. No significant cross-sectional differences were observed between other strata. Men with structural progression appeared to have a greater longitudinal increase in SCF (+13.2%; P < 0.05) than did men without progression (-1.9%), and women with progression appeared to have a greater increase in IMF (+11.6%) than did those without progression (+1.5%).

CONCLUSION

In women, painful knees display greater IMF content than do contralateral pain-free knees. Other between-knee comparisons did not reveal a regional association between radiographic KOA and thigh adipose tissue status. Structural progression of KOA may be associated with greater longitudinal increases in SCF in men and greater increases of IMF in women, compared with nonprogressive controls.

¹⁸F-FPRGD₂ PET/CT imaging of musculoskeletal disorders

OBJECTIVE

This work reports on musculoskeletal uptake of ¹⁸F-FPRGD₂, targeting the integrin αvβ3, in patients who had undergone ¹⁸F-FPRGD₂ positron emission tomography combined with computed tomography (PET/CT) for oncologic purposes.

METHODS

Whole-body ¹⁸F-FPRGD₂ PET/CT images of 62 cancer patients were retrospectively reviewed to detect foci of musculoskeletal ¹⁸F-FPRGD₂ uptake. For 37 patients, a FDG PET/CT performed in clinical settings was available. In each joint with an abnormal uptake, the maximum standardized uptake value (SUVmax) was estimated.

RESULTS

A total of 260 musculoskeletal foci of ¹⁸F-FPRGD₂ uptake were detected. Most common sites of uptake were joints and discs (n = 160; 61.5%), entheses (osteotendinous and osteoligamentous junctions; n = 55; 21.2%) and recent fractures (n = 18; 6.9%). In addition, 27 (10.4%) miscellaneous foci were detected. Out of the 146 lesions for which a FDG PET was available, 63% showed both ¹⁸F-FPRGD₂ and FDG uptake, 33.6% did not show FDG avidity and 3.4% showed only FDG uptake. The uptake intensity of the 92 lesions positive with ¹⁸F-FPRGD₂ and FDG was similar with both radiopharmaceuticals, but the target-to-background (blood pool or muscle) ratios were significantly higher with ¹⁸F-FPRGD₂ than with FDG (p < 0.0001).

CONCLUSION

The ¹⁸F-FPRGD₂ uptake in joints, spine degenerative diseases and tendons was highly prevalent in our population. Up to one-third of ¹⁸F-FPRGD₂ foci showed no FDG uptake suggesting that ¹⁸F-FPRGD₂ signal may not be related to inflammatory angiogenesis only.

Consequences of metabolic and oxidative modifications of cartilage tissue

A hallmark of chronic metabolic diseases, such as diabetes and metabolic syndrome, and oxidative stress, as occurs in chronic inflammatory and degenerative conditions, is the presence of extensive protein post-translational modifications, including glycation, glycoxidation, carbonylation and nitrosylation. These modifications have been detected on structural cartilage proteins in joints and intervertebral discs, where they are known to affect protein folding, induce protein aggregation and, ultimately, generate microanatomical changes in the proteoglycan-collagen network that surrounds chondrocytes. Many of these modifications have also been shown to promote oxidative cleavage as well as enzymatically-mediated matrix degradation. Overall, a general picture starts to emerge indicating that biochemical changes in proteins constitute an early event that compromises the anatomical organization and viscoelasticity of cartilage, thereby affecting its ability to sustain pressure and, ultimately, impeding its overall bio-performance.

The adverse effects of diabetes on osteoarthritis: update on clinical evidence and molecular mechanisms

Projected increases in the prevalence of both diabetes mellitus (DM) and osteoarthritis (OA) ensure their common co-existence. In an era of increasing attention to personalized medicine, understanding the influence of common comorbidities such as DM should result in improved care of patients with OA. In this narrative review, we summarize the literature addressing the interactions between DM and OA spanning the years from 1962 to 2014. We separated studies depending on whether they investigated clinical populations, animal models, or cells and tissues. The clinical literature addressing the influence of DM on OA and its therapeutic outcomes suggests that DM may augment the development and severity of OA and that DM increases risks associated with joint replacement surgery. The few high quality studies using animal models also support an adverse effect of DM on OA. We review strengths and weaknesses of the common rodent models of DM. The heterogeneous literature derived from studies of articular cells and tissues also supports the existence of biochemical and biomechanical changes in articular tissues in DM, and begins to characterize molecular mechanisms activated in diabetic-like environs which may contribute to OA. Increasing evidence from the clinic and the laboratory supports an adverse effect of DM on the development, severity, and therapeutic outcomes for OA. To understand the mechanisms through which DM contributes to OA, further studies are clearly necessary. Future studies of DM-influenced mechanisms may shed light on general mechanisms of OA pathogenesis and result in more specific and effective therapies for all OA patients.

Impact of disease treatments on the progression of knee osteoarthritis structural changes related to meniscal extrusion: Data from the OAI progression cohort

OBJECTIVE

In the perspective of personalized management of osteoarthritis (OA), a clinically relevant concern is the impact of meniscal extrusion (Ext) on response to treatment. This study aimed at determining the effects of conventional OA pharmacological treatments and those of the combination of glucosamine and chondroitin sulfate (Glu/CS) on knee structural changes in the presence or absence of Ext, using data from the progression cohort of the Osteoarthritis Initiative.

METHODS

In this longitudinal study, knee OA participants were stratified based on whether (+) or not (-) they received analgesics/NSAIDs (+ and -analgesics/NSAIDs) and/or Glu/CS (+ and -Glu/CS) for 24 consecutive months and on the presence (Ext+) or absence (Ext-) of medial meniscal extrusion at baseline. The main outcomes were knee structural changes including the loss of joint space width (JSW) and cartilage volume loss measured by quantitative MRI.

RESULTS

In both - and +analgesics/NSAIDs groups (n = 300 each), the Ext+ participants had more-advanced disease at baseline (T0) and more JSW loss and cartilage volume loss in the medial compartment (p ≤ 0.003, univariate; p ≤ 0.049, multivariate analyses) at both 12 (T12) and 24 (T24) months compared to Ext- participants. In the -analgesics/NSAIDs group, Ext+ participants taking Glu/CS had significantly less cartilage volume loss in the medial plateau at T24 (p ≤ 0.010, univariate and multivariate analyses). In the +analgesics/NSAIDs group at T24, Ext- participants taking Glu/CS had less cartilage volume loss in the global (p ≤ 0.002, univariate and multivariate analyses) and medial and lateral plateaus (p = 0.034 and p = 0.013, respectively, multivariate analysis). No significant difference in JSW loss was found between the groups.

CONCLUSION

This study is the first to demonstrate, using qMRI, that meniscal extrusion can modify the response to Glu/CS treatment in knee OA patients, depending on the severity of the disease.

Osteoarthritis in the XXIst century: risk factors and behaviours that influence disease onset and progression

Osteoarthritis (OA) is a growing public health problem across the globe, affecting more than half of the over 65 population. In the past, OA was considered a wear and tear disease, leading to the loss of articular cartilage and joint disability. Nowadays, thanks to advancements in molecular biology, OA is believed to be a very complex multifactorial disease. OA is a degenerative disease characterized by “low-grade inflammation” in cartilage and synovium, resulting in the loss of joint structure and progressive deterioration of cartilage. Although the disease can be dependent on genetic and epigenetic factors, sex, ethnicity, and age (cellular senescence, apoptosis and lubricin), it is also associated with obesity and overweight, dietary factors, sedentary lifestyle and sport injuries. The aim of this review is to highlight how certain behaviors, habits and lifestyles may be involved in the onset and progression of OA and to summarize the principal risk factors involved in the development of this complicated joint disorder.

Osteoarthritis year in review 2014: clinical

A systematic search was conducted for the time period April 1 2013 to March 30 2014 using PubMed to identify major osteoarthritis (OA) clinical research themes of the past year. Articles within each theme were selected for inclusion in this review based on study quality and relevance. Two major themes emerged, which relate to the current understanding of OA as a heterogeneous condition with multiple pathogenic mechanisms and clinical manifestations. Theme 1 stems from the role of systemic inflammation in OA pathogenesis, and the concept of 'metabolic OA'. Over the past year, research has examined the effect of OA on incidence and progression of other 'metabolic syndrome'-related conditions, especially cardiovascular disease (CVD) and diabetes and the impact of multi-morbidity on the clinical management of OA. Theme 2 focuses on the concept of personalized medicine as it relates to the treatment of OA. It is hypothesized that the modest efficacy of available OA treatments is a result of inclusion of heterogeneous groups of OA patients in clinical trials. Prognostic studies in the past year have been helpful in identifying 'OA phenotypes' that are more or less likely to respond to treatments--e.g., the presence of synovitis on imaging, central pain sensitization on quantitative sensory testing (QST), or coping efficacy by self-reported patient questionnaire. Their findings are being increasingly used to target interventions to these identified 'OA responder' subgroups with the hopes that treatment effect will be amplified.

Imaging research results from the osteoarthritis initiative (OAI): a review and lessons learned 10 years after start of enrolment

The Osteoarthritis Initiative (OAI) is a multicentre, prospective, observational, cohort study of knee osteoarthritis (OA) that began recruitment in 2004. The OAI provides public access to clinical and image data, enabling researchers to examine risk factors/predictors and the natural history of knee OA incidence and progression, and the qualification of imaging and other biomarkers. In this narrative review, we report imaging findings and lessons learned 10 years after enrolment has started. A literature search for full text articles published from the OAI was performed up to 31 December 2013 using Pubmed and the OAI web page. We summarise the rationale, design and imaging protocol of the OAI, and the history of OAI publications. We review studies from early partial, and later full OAI public data releases. The latter are structured by imaging method and tissue, reviewing radiography and then MRI findings on cartilage morphology, cartilage lesions and composition (T2), bone, meniscus, muscle and adipose tissue. Finally, analyses directly comparing findings from MRI and radiography are summarised. Ten years after the first participants were enrolled and first papers published, the OAI has become an invaluable resource to the OA research community. It has fuelled novel methodological approaches of analysing images, and has provided a wealth of information on OA pathophysiology. Continued collection and public release of long-term observations will help imaging measures to gain scientific and regulatory acceptance as 'prognostic' or 'efficacy of intervention' biomarkers, potentially enabling shorter and more efficient clinical trials that can test structure-modifying therapeutic interventions (NCT00080171).