Erosive osteoarthritis: a current review of a clinical challenge

Current Epidemiology and Risk Factors for the Development of Hand Osteoarthritis

PURPOSE OF REVIEW

Hand osteoarthritis (hand OA), the most common peripheral arthritis in the world, is less studied than osteoarthritis (OA) of the knee and hip. However, it is uniquely situated to offer novel insight into OA as a disease process by removing weight-bearing as a confounder of systemic disease mechanisms. Here we review the epidemiology of hand OA and key risk factors for its development.

RECENT FINDINGS

Mounting evidence points to obesity as an important risk factor for hand OA development, with new evidence implicating a role for leptin and serum fatty acids. Disease progression in hand OA and specifically the erosive OA subtype may be associated with diabetes. New evidence supports an association between cardiovascular disease progression and symptomatic hand OA. Alcohol use may be associated with increased synovitis and erosive hand OA. Differences in ethnical distributions of hand OA have become more apparent, with a lower prevalence in Black patients compared to White patients. Novel genetic insights implicating the WNT gene pathway and IL-1β have led to novel potential targets in hand OA pathogenesis. Hand OA is a heterogeneous disease with many modifiable and non-modifiable risk factors that can determine disease severity and shed light on disease pathogenesis.

Erosive Hand Osteoarthritis: Incidence and Predictive Characteristics among Participants in the Osteoarthritis Initiative

OBJECTIVE

To evaluate age, sex, race, osteoarthritis severity, metabolic factors, and bone health as risk factors for incident erosive hand osteoarthritis (EHOA) at baseline and over 48-month period.

METHODS

This study was a longitudinal cohort design including participants from the Osteoarthritis Initiative with complete hand radiographs from baseline and 48-month visits who were eligible at baseline for incident EHOA. Individuals were classified as having EHOA if they had Kellgren-Lawrence (KL) grade≥2 in at least one interphalangeal joint on two different fingers and central erosion in at least one joint.

RESULTS

Of the 3365 individuals identified without prevalent EHOA at baseline, 86 (2.6%) developed EHOA during the 48-month period. Risk factors included being older [relative risk (RR) per standard deviation=0.76 (95% confidence interval 0.59, 0.98)], female [RR=1.73 (1.05, 2.85)], greater osteoarthritis severity (sum of KL grade 13.9 vs. 5.3, p<0.001) and less cortical width (1.38 vs 1.52 mm, p<0.001). After 48 months, people who developed EHOA were characterized by greater progressions of radiographic osteoarthritis (i.e., joint space narrowing, KL grade progression [RRs = 1.35 to 1.9] and loss of cortical thickness [RR = 1.23], adjusted for age, sex, race, body mass index, and baseline osteoarthritis severity (sum KL scores).

CONCLUSION

These findings present EHOA as a disorder of advanced age and female sex, strongly associated with severity of articular structural damage and its progression. Individuals who develop EHOA have thinner bones prior to EHOA development and as it progresses, suggesting EHOA as a disorder of skeletal frailty.

Familial Clustering of Erosive Hand Osteoarthritis in a Large Statewide Cohort

OBJECTIVE

Erosive hand osteoarthritis (OA) is a severe and rapidly progressing subset of hand OA. Its etiology remains largely unknown, which has hindered development of successful treatments. This study was undertaken to test the hypothesis that erosive hand OA demonstrates familial clustering in a large statewide population linked to genealogical records, and to determine the association of potential risk factors with erosive hand OA.

METHODS

Patients diagnosed as having erosive hand OA were identified by searching 4,741,840 unique medical records from a comprehensive statewide database, the Utah Population Database (UPDB). Affected individuals were mapped to pedigrees to identify high-risk families with excess clustering of erosive hand OA as defined by a familial standardized incidence ratio (FSIR) of ≥2.0. The magnitude of familial risk of erosive hand OA in related individuals was calculated using Cox regression models. Association of potential erosive hand OA risk factors was analyzed using multivariate conditional logistic regression and logistic regression models.

RESULTS

We identified 703 affected individuals linked to 240 unrelated high-risk pedigrees with excess clustering of erosive hand OA (FSIR ≥2.0, P < 0.05). The relative risk of developing erosive hand OA was significantly elevated in first-degree relatives (P < 0.001). There were significant associations between a diagnosis of erosive hand OA and age, sex, diabetes, and obesity (all P < 0.05).

CONCLUSION

Familial clustering of erosive hand OA observed in a statewide database indicates a potential genetic contribution to the etiology of the disease. Age, sex, diabetes, and obesity are risk factors for erosive hand OA. Identification of causal gene variants in these high-risk families may provide insight into the genes and pathways that contribute to erosive hand OA onset and progression.

The Diagnostic Implications of Two Cases of Known Rheumatoid Arthritis from the CAL Milano Cemetery Skeletal Collection

Rheumatoid arthritis (RA) is the most common erosive arthropathy and is of particular interest to forensic sciences. However, its diagnosis on bones remains challenging. We examined two skeletons from the CAL Milano Cemetery Skeletal Collection diagnosed with the pathology during life, to test the validity of the diagnostic criteria on bones. The first showed typical lesions of RA described in the literature. The second exhibited secondary osteoarthrosis, suggesting long-standing RA. A differential diagnosis including all four seronegative spondyloarthropathies, erosive osteoarthritis, gout and neuropathic arthropathy was also considered. Both shared common features consistent with the literature: symmetric erosions of bones in the hands, wrists and elbows, sparing of the distal interphalangeal joints, and the absence of sacroiliac and spinal fusion. Given the paucity of studies on known RA skeletons, these results strengthen the criteria for diagnosis. This research is, to our knowledge, the first study on identified and known individuals with RA.

Why location matters - site-specific factors in rheumatic diseases

Rheumatic diseases follow a characteristic anatomical pattern of joint and organ involvement. This Review explores three interconnected mechanisms that might be involved in the predilection of specific joints for developing specific forms of arthritis: site-specific local cell types that drive disease; systemic triggers that affect local cell types; and site-specific exogenous factors, such as focal mechanical stress, that activate cells locally. The embryonic development of limbs and joints is also relevant to the propensity of certain joints to develop arthritis. Additionally, location-specific homeostasis and disease occurs in skin and blood vessels, thereby extending the concept of site-specificity in human diseases beyond rheumatology. Acknowledging the importance of site-specific parameters increases the complexity of current disease paradigms and brings us closer to understanding why particular disease processes manifest at a particular location.

Epigenetically-driven anatomical diversity of synovial fibroblasts guides joint-specific fibroblast functions

A number of human diseases, such as arthritis and atherosclerosis, include characteristic pathology in specific anatomical locations. Here we show transcriptomic differences in synovial fibroblasts from different joint locations and that HOX gene signatures reflect the joint-specific origins of mouse and human synovial fibroblasts and synovial tissues. Alongside DNA methylation and histone modifications, bromodomain and extra-terminal reader proteins regulate joint-specific HOX gene expression. Anatomical transcriptional diversity translates into joint-specific synovial fibroblast phenotypes with distinct adhesive, proliferative, chemotactic and matrix-degrading characteristics and differential responsiveness to TNF, creating a unique microenvironment in each joint. These findings indicate that local stroma might control positional disease patterns not only in arthritis but in any disease with a prominent stromal component.

Arthritis affects different joints variably despite systemic inflammatory cues. Here the authors show anatomical differences in the transcriptome, epigenome and function of synovial fibroblasts that might affect susceptibility to site-specific joint diseases.

Erosive osteoarthritis: A systematic analysis of definitions used in the literature

BACKGROUND

Erosive osteoarthritis (EOA) is a commonly invoked diagnosis representing an important variant of hand osteoarthritis (OA). There is increasing literature on the prevalence, risk factors, etiology, and management of EOA.

METHODS

We systematically reviewed the literature to assess variability in the diagnostic definitions used to define EOA in these studies.

RESULTS

We reviewed 336 articles and found 62 articles citing diagnostic definitions for EOA. Radiographic appearance was the most commonly used criterion, but there was little agreement on the details or extent of the radiographic changes. Overall, 56 of the 62 studies included clinical features in the diagnostic definitions, yet these features varied considerably. Exclusion criteria were mentioned in 43 of the studies.

CONCLUSION

Based on the widely disparate definitions of EOA, we urge caution in interpretation of this literature, and propose that further understanding of EOA will require consensus on its definition.

Ultrasound detected inflammation is associated with the development of new bone erosions in hand osteoarthritis: a longitudinal study over 3.9 years

OBJECTIVE

To evaluate the association between ultrasound (US) detected inflammation at baseline and the subsequent development of new bone erosions at follow-up in patients with hand osteoarthritis (HOA).

METHOD

32 of the 35 (10 controls, 12 patients with non erosive HOA (non-EHOA), 13 with EHOA subjects originally studied were re-evaluated 3.9 years after the initial study, by means of standard radiography and US examination. Kellgren-Lawrence (K-L) and Kallman scores were utilized to evaluate 576 interphalangeal (IP) joints. US detected synovial inflammation features were scored as present/absent. US detected bone erosions were also investigated. The association between synovial inflammation features at baseline and the development of new bone erosions was evaluated using the generalized linear mixed model (GLMM) after adjustment for patient effect, age, gender, body mass index.

RESULTS

In HOA patients, radiographic scores worsened and bone erosions progressed. In HOA patients similar percentages of joints with Power Doppler Signal (PDS) and gray scale (GS) synovitis were found comparing baseline and follow-up examinations, whilst a significant increase was found in the joints with effusions. Only a minority of joints were positive on both occasions (between 2 and 6 %), the majority fluctuated between positive and negative and vice versa. PDS positivity was associated with new radiographic central erosions and US-detected bone erosions, whereas GS synovitis and effusion were not.

CONCLUSIONS

Radiographic scores and bone erosions increased over a period of about 4 years. Synovial inflammation as detected by PDS was associated with the appearance of new bone erosions.

Association of adiponectin +276G/T polymorphism with knee osteoarthritis

Osteoarthritis (OA) is a prevalent, degenerative joint disorder leading to the destruction of articular cartilage, osteophyte formation and subchondral bone sclerosis. Genetic and environmental factors are involved in the development of OA. The role of adiponectin gene polymorphisms in OA has not yet been established. The aim of this study was to investigate the association of adiponectin +276G/T (rs1501299) gene polymorphism with knee OA. Genotype distributions and allelic frequencies of adiponectin gene, +276G/T polymorphism were determined in a total of 200 subjects (100 knee OA patients and 100 healthy controls). Single-nucleotide polymorphism (SNP) of the adiponectin +276G/T gene was genotyped by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis. The genotype distribution of +276G/T SNP was observed in the Hardy-Weinberg equilibrium for OA patients and controls. No statistically significant difference was identified between the two groups with respect to genotype distributions and allelic frequencies (P>0.05). The T- and G-allele frequencies were indicated as 24.5 and 75.5%, respectively, in OA patients, whereas the frequency was 23-70% in the control group. Findings of this study therefore suggest that the +276G/T SNP was not associated with susceptibility to knee OA.

Identifying phenotypes of knee osteoarthritis by separate quantitative radiographic features may improve patient selection for more targeted treatment

OBJECTIVE

Expression of osteoarthritis (OA) varies significantly between individuals, and over time, suggesting the existence of different phenotypes, possibly with specific etiology and targets for treatment. Our objective was to identify phenotypes of progression of radiographic knee OA using separate quantitative features.

METHODS

Separate radiographic features of OA were measured by Knee Images Digital Analysis (KIDA) in individuals with early knee OA (the CHECK cohort: Cohort Hip & Cohort Knee), at baseline and at 2-year and 5-year followup. Hierarchical clustering was performed to identify phenotypes of radiographic knee OA progression. The phenotypes identified were compared for changes in joint space width (JSW), varus angle, osteophyte area, eminence height, bone density, for Kellgren-Lawrence (K-L) grade, and for clinical characteristics. Logistic regression analysis evaluated whether baseline radiographic features and demographic/clinical characteristics were associated with each of the specific phenotypes.

RESULTS

The 5 clusters identified were interpreted as "Severe" or "No," "Early" or "Late" progression of the radiographic features, or specific involvement of "Bone density." Medial JSW, varus angle, osteophyte area, eminence height, and bone density at baseline were associated with the Severe and Bone density phenotypes. Lesser eminence height and bone density were associated with Early and Late progression. Larger varus angle and smaller osteophyte area were associated with No progression.

CONCLUSION

Five phenotypes of radiographic progression of early knee OA were identified using separate quantitative features, which were associated with baseline radiographic features. Such phenotypes might require specific treatment and represent relevant subgroups for clinical trials.

Treatment of erosive osteoarthritis with peroxisome proliferator-activated receptor alpha agonist fenofibrate: a pilot study

Hand osteoarthritis (HOA) is a common condition associated with high disease burden and frequently accompanied by comorbidities including dyslipidemia, atherosclerosis and obesity. The most debilitating HOA phenotype is erosive HOA (EHOA), characterized by synovial inflammation, formation of erosions, and substantial decline in hand function. Currently, there is no proven symptomatic treatment for the EHOA. Due to their broad spectrum effects directed on lipid metabolism, inflammation and pain, the agonists of peroxisome proliferator-activated receptor alpha or fibrates are a candidate class of drugs for the treatment of EHOA. In this study, we assessed the influence of fenofibrate treatment on clinical efficacy parameters, in vivo cytokine and adipokine production and concentrations of endothelial progenitor cells (EPC) in patients with EHOA. Fourteen patients received treatment with 145 mg of fenofibrate/day for 12 weeks. Fenofibrate treatment was associated with significant decreases in pain score, tender joint count, duration of morning stiffness, disease activity score, Cochin index, and ESR. Eight (57.14 %) patients developed Outcome Measures in Rheumatology Clinical Trials-Osteoarthritis Research Society response at the end of treatment. Paracetamol consumption did not change during the treatment course. There was a significant reduction in triglyceride levels. No changes were detected in serum pro-inflammatory cytokine and adipokine concentrations while circulating IL-10 levels significantly decreased. There were no differences in circulating EPC numbers before and after the treatment. Fenofibrate was well tolerated, no patient experienced disease flare during the treatment. In conclusion, in EHOA patients, fenofibrate is associated with pleiotropic effects on pain, inflammation, and lipid profile. Larger, controlled studies are needed to confirm these results.

3 T DCE-MRI assessment of synovitis of the interphalangeal joints in patients with erosive osteoarthritis for treatment response monitoring

OBJECTIVE

To study the value of 3 T dynamic contrast-enhanced (DCE)-MRI for assessment of synovitis of the interphalangeal joints in patients with erosive osteoarthritis (EOA) for treatment response monitoring.

MATERIALS AND METHODS

The interphalangeal joints of fingers two to five were examined at 3 T MRI in nine patients with EOA. Two musculoskeletal radiologists recorded erosions, bone marrow oedema (BME), synovitis and osteophytes. Interobserver reliability was calculated using κ statistics. In six patients, DCE-MRI time intensity curves of synovitis in two affected joints were analysed. The maximum upslope, absolute and relative enhancement of synovitis were compared with MRI after 12 months of anti-tumour necrosis factor treatment. Intraobserver reproducibility was calculated using intra-class correlation coefficient.

RESULTS

Interobserver reliability was 'good' for detection of erosions (κ = 0.70), BME (κ = 0.77) and synovitis (κ = 0.77), but 'poor' for osteophytes (κ = 0.12). Post-treatment DCE-MRI showed decreasing maximum upslope (p = 0.002) and absolute (p = 0.002) and relative (p = 0.01) enhancement compared to the initial scan. Intraobserver reproducibility of DCE-MRI was 'almost perfect' or 'strong' for all parameters.

CONCLUSIONS

3 T DCE-MRI demonstrates changes in time intensity curves of synovitis in EOA of the interphalangeal joints in a longitudinal study, indicating this technique is promising for monitoring therapy response.

Association of MMP-3 (-1612 5A/6A) polymorphism with knee osteoarthritis in Thai population

Osteoarthritis (OA) is a degenerative joint disorder resulting in destruction of articular cartilage, osteophyte formation, and subchondral bone sclerosis. In recent years, numerous genetic factors have been identified and implicated in causing osteoarthritis. One such genetic defect is a single nucleotide polymorphism at position -1612 of matrix metalloproteinase-3 (MMP-3) promoter region, known to lead to three possible genotypes, 5A/5A, 6A/6A, and 5A/6A. The purpose of this study was to investigate the association of MMP-3 -1612 5A/6A gene polymorphism with knee osteoarthritis in Thai population. Genotype distributions and allelic frequencies of MMP-3 -1612 5A/6A polymorphism were investigated in 200 participants (100 patients with knee osteoarthritis and 100 healthy controls). Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism. There was no statistically significant difference between the groups with respect to genotype distribution (P > 0.05). The 5A allele frequency was indicated as 15.5 %, and 6A allele was as 84.5 % in OA patients, whereas it was 10-90 % in the control group. Accordingly, the present study has indicated that the -1612 5A/6A polymorphism genotypes of MMP-3 gene promoter do not play a role in the development of osteoarthritis in the Thai population.

Assessment of synovitis in erosive osteoarthritis of the hand using DCE-MRI and comparison with that in its major mimic, the psoriatic arthritis

RATIONALE AND OBJECTIVES

To investigate the diagnostic value of high-resolution dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for assessment of synovitis in erosive osteoarthritis (EOA) of the hand and compare the results with those acquired in its potential mimic, the psoriatic arthritis (PsA).

MATERIALS AND METHODS

Twenty-six patients (17 PsA, 9 EOA) were examined at 3 T. The time course of synovial contrast uptake was measured by ROI analysis using a three-dimensional encoded spoiled gradient-echo sequence. Characteristic parameters of synovial uptake curves (time to peak [TTP], peak value, mean transit time [MTT], area under the curve [AUC], and maximum upslope) of PsA and EOA patients were compared using gamma variate analysis and calculation of the late relative enhancement 15 minutes after contrast administration.

RESULTS

Enhancement curves of PsA and EOA patients paralleled each other at comparable levels in the early phase after contrast injection without statistical difference in the following calculated characteristic curve parameters: TTP, peak value, MTT, AUC, and maximum upslope. However, significant difference was found in the late relative enhancement 15 minutes after contrast injection (P = .0275) with higher values in EOA patients.

CONCLUSION

DCE-MRI provides assessment of synovitis in both patients with EOA and PsA. Interestingly, synovial enhancement characteristics were comparable for the most part in these two disorders. However, late enhancement might help in differentiation which is essential for guiding therapy.

[Therapeutic strategies in erosive digital polyarthrosis]

One of the most common forms of osteoarthritis is hand osteoarthritis. A subgroup, termed erosive hand osteoarthritis (EHOA), shows a highly destructive disease course with involvement of multiple joints, swelling as well as cartilage and bone destruction leading to progressive loss of hand function. EHOA is characterized by subchondral erosions of the finger joints as well as ankylosis. No disease modifying therapy is currently available for the treatment of EHOA and treatment options are confined to the control of symptoms. Acetaminophen and non-steroidal anti-inflammatory drugs are used to treat the signs and symptoms. So far cytokine blocking agents have not shown a convincing therapeutic effect and the effect size of chondroitin sulfate and bisphosphonates in EOHA is small.