Associations of inflammatory and metabolic biomarkers with incident erosive hand osteoarthritis in the osteoarthritis initiative cohort.

OBJECTIVE: Erosive hand osteoarthritis (eHOA) is a subtype of hand osteoarthritis (OA) that develops in finger joints with pre-existing OA and is differentiated by clinical characteristics (hand pain/disability, inflammation, and erosions) that suggest inflammatory or metabolic processes. METHOD: This was a longitudinal nested case-cohort design among Osteoarthritis Initiative participants who had hand radiographs at baseline and 48-months, and biospecimens collected at baseline. We classified incident radiographic eHOA in individuals with ≥1 joint with Kellgren-Lawrence ≥2 and a central erosion present at 48-months but not at baseline. We used a random representative sample (n = 1282) for comparison. We measured serum biomarkers of inflammation, insulin resistance and dysglycemia, and adipokines using immunoassays and enzymatic colorimetric procedures, blinded to case status. RESULTS: Eighty-six participants developed incident radiographic eHOA. In the multivariate analyses adjusted for age, gender, race, smoking, and body mass index, and after adjustment for multiple analyses, incident radiographic eHOA was associated with elevated levels of interleukin-7 (risk ratio (RR) per SD = 1.30 [95% confidence interval (CI) 1.09, 1.55] p trend 0.01). CONCLUSION: This exploratory study suggests an association of elevated interleukin-7, an inflammatory cytokine, with incident eHOA, while other cytokines or biomarkers of metabolic inflammation were not associated. Interleukin-7 may mediate inflammation and tissue damage in susceptible osteoarthritic finger joints and participate in erosive progression.

Gender and age differences in the associations between cortical thickness and hand osteoarthritis severity: data from the Osteoarthritis Initiative.

OBJECTIVE: To evaluate gender differences in the association between metacarpal cortical thickness (Tcort)-a surrogate for bone density-and severity of radiographic hand osteoarthritis (HOA) in a longitudinal observational study. METHOD: Hand radiographs of 3575 participants (2039 F/1536 M) from the Osteoarthritis Initiative were assessed at baseline and 48 months. A reader used a semi-automated software tool to calculate Tcort, a measurement of the cortical thickness, for metacarpals 2-4. Average Tcort at baseline and change in Tcort from baseline to 48 months was determined and stratified by gender and age for 7 5-year age groups. Spearman's rank correlation coefficients were calculated for the association of baseline Tcort and 2 measures of baseline HOA severity: the sum of Kellgren-Lawrence (KL) grade and total number of joints with radiographic HOA. Longitudinally, logistic regression was used to assess the relationship of Tcort loss to new finger joint radiographic HOA, increase in KL grades, and incident hand pain. RESULTS: Male Tcort was higher than females. Significant correlations between Tcort and radiographic severity were noted for women but not men, with stronger associations among women >60 years (rho = -0.25; 95% confidence interval (CI) = -0.31 to -0.19). Statistically significant associations were seen between Tcort change and radiographic osteoarthritis change among women but not men, with substantial gender differences for Tcort change, particularly ages 50 to 70 years (p < 0.01; e.g., Tcort change ages 55 to <60: males = -0.182 (0.118), females = -0.219 (0.124)). CONCLUSION: We found significant HOA-related gender differences in Tcort, suggesting the involvement of female bone loss during and after menopause.

Evaluation of circulating microRNA signature in patients with erosive hand osteoarthritis: The HOAmiR study.

OBJECTIVES: To identify circulating micro-RNAs differentially expressed in patients with erosive hand osteoarthritis (HOA) compared to patients with non-erosive HOA and patients without HOA. METHODS: In the screening phase, 768 well-characterized micro-RNAs using Taqman low-density array cards were measured in 30 sera from 10 patients with erosive HOA, 10 patients with non-erosive HOA, and 10 controls without HOA, matched for age and body mass index (BMI). In a second step, we validated the micro-RNAs identified at the screening phase (adjusted p value < 0.05 after false discovery rate correction using Benjamini-Hochberg method and literature review) in larger samples (60 patients with erosive HOA and 60 patients without HOA matched for age and BMI). RESULTS: In the screening phase, we identified 21 down-regulated and 4 up-regulated micro-RNAs of interest between erosive HOA and control groups. Among these, 9 micro-RNAs (miR-373-3p, miR-558, miR-607, miR-653-5p, miR-137 and miR448 were down-regulated, and miR-142-3p, miR-144-3p and miR-34a-5p were up-regulated) were previously described in chondrocytes homeostasis or OA. We found only one significantly down-regulated micro-RNA between erosive and non-erosive HOA. In the validation phase, we showed replication of a single micro-RNA the significant downregulation of miR-196-5p, that had been previously identified in the screening phase among patients with erosive HOA compared to those without HOA. After reviewing the literature and the miRNA-gene interaction prediction model, we found that this microRNA could interact with bone homeostasis and HOXC8, which could explain its role in osteoarthritis. CONCLUSIONS: We found that miR-196-5p was down-regulated in patients with erosive HOA and some of its targets could explain a role in OA.

Hand osteoarthritis phenotypes based on a biopsychosocial approach, and their associations with cross-sectional and longitudinal pain.

OBJECTIVE: Hand osteoarthritis (OA) pain is characterized as heterogeneous and multifactorial. Differences in pain may be explained by underlying phenotypes, which have not been previously explored DESIGN: Latent class analysis determined classes of participants with hand OA from the Nor-Hand study baseline examination (2016-17) based on a biopsychosocial framework. Outcomes were hand and overall bodily pain intensity (Numeric Rating Scale, 0-10) at baseline and follow-up (2019-21), The relations of the classes to pain outcomes at baseline, follow-up, and change over time were analysed in separate models by linear regression, using the overall healthiest class as reference. RESULTS: Five classes differing in radiographic hand OA burden and OA burden in the lower extremities by ultrasound, demographic factors, psychosocial burden and pain sensitization was identified. Persons with the least severe OA but higher burden of biopsychosocial factors reported the most hand pain (beta 3.65, 95% CI 2.53, 4.75). Pain was less pronounced in persons with the most severe hand OA but low burden of biopsychosocial factors (beta 1.03, 95% CI 0.41, 1.65). Results were similar for overall bodily pain and at follow-up. Changes in pain were small, but the association between a separate class defined by higher levels of biopsychosocial burden and pain changes was significant. CONCLUSION: The five hand OA phenotypes were associated with pain at baseline and 3.5 years later. The phenotype with the least OA severity, but higher burden of biopsychosocial factors reported more pain than the phenotype with the most severe OA, reflecting the symptom-structure discordance of the hand OA pain experience.

Tendon involvement and its association with pain and hand function in patients with osteoarthritis of the hand.

OBJECTIVE: To characterise the frequency and influence of tenosynovitis and tendon damage on pain and hand function using clinical examination and ultrasound (US) in hand osteoarthritis (HOA). METHODS: We included 86 patients with HOA and 23 age- and sex-matched control subjects. Extensor and flexor tendons of both hands were assessed by clinical examination and US for tenosynovitis, tendon damage. Conventional radiographs were acquired. Hand function was evaluated by the function subtest of the M-SACRAH questionnaire and the Moberg pick-up test. K-means cluster analyses was calculated to assess clusters based on radiographic features and sonographic tendon scores. RESULTS: Ultrasound identified the involvement of ≥ 1 tendon in 60/86 (69.8%) HOA patients compared with 2/23 (8.7%) subjects (p< 0.01) in the control group. In the HOA group, US detected tendon damage more often in flexor tendons compared with extensor tendons (2.1% 0.9%, p= 0.03), while tenosynovitis was observed more often in extensor tendons compared with flexor tendons (8% vs 0.6%, p< 0001). The sensitivity and specificity of clinical examination to detect tendon involvement was 81.4% and 34.6%, respectively on the patient level and 14.5% and 83.8% on the tendon level. The cluster analyses revealed one cluster with more radiographic features of HOA and more tendon damage while more tenosynovitis was found in cluster 2. M-SACRAH function did not correlate with tendon involvement on US. CONCLUSION: This study revealed a high frequency of tendon involvement in HOA. Tendon involvement on US did not impact hand function or self-reported pain.

Erosive Hand Osteoarthritis: Recent Advances and Future Treatments.

PURPOSE OF THE REVIEW: Erosive hand osteoarthritis (EHOA) is an aggressive form of hand osteoarthritis that leads to significant disability, and recent data suggests that it is increasing in prevalence. This review provides an update of our current understanding of epidemiology, genetic associations, biomarkers, pathogenesis, and treatment of EHOA, with particular focus on studies published within the last 5 years. RECENT FINDINGS: New studies of EHOA have identified new genetic loci associated with disease, including variants in genes involved in inflammation and bone remodeling. Preclinical studies implicate pathways of innate immunity, including some that may be causal in the condition. Recent novel studies showed that inflammatory features identified by ultrasound and MRI are associated with development of erosive lesions over time on conventional radiography. In the future, these imaging modalities may be useful in identifying patients at risk of adverse outcomes. Promising new findings in genetics, biomarkers, and treatment targets will hopefully allow for future therapeutic options for this debilitating condition.

A functional variant of ALDH1A2 is associated with hand osteoarthritis in the Chinese population.

Genome-wide association study identified common variants within the ALDH1A2 gene as the susceptible loci of hand osteoarthritis (HOA) in UK and Iceland populations. Located in chromosome 15, ALDH1A2 encodes aldehyde dehydrogenase family 1 member A2, which is an enzyme that catalyses the synthesis of retinoic acid from retinaldehyde. Our purposes were to replicate the association of functional variant in ALDH1A2 with the development of HOA in the Chinese population. Variant rs12915901 of ALDH1A2 was genotyped in 872 HOA patients and 1223 healthy controls. Subchondral bone samples were collected from 40 patients who had undergone a trapeziectomy, and the tissue expression of ALDH1A2 was analysed. The chi-square analysis was used to compare the frequency of genotype and risk allele between the HOA cases and controls. The Student t test was used to compare the mRNA expression of ALDH1A2 between patients with genotype AA/AG and those with genotype GG. The frequency of genotype AA was significantly higher in HOA patients than in the controls (7.6% vs. 5.1%, p = .01). The frequency of allele A was significantly higher in the patients than in the controls (28.9% vs. 24.6%, p = .005). The mRNA expression of ALDH1A2 was 1.31-folds higher in patients with genotype GG than in the patients with genotype AA/AG (0.000617 ± 0.000231 vs. 0.000471 ± 0.000198, p = .04). Variant rs12915901 of ALDH1A2 contributed to the susceptibility of HOA in the Chinese population. Allele A of rs12915901 can add to the risk of HOA possibly via down-regulation of ALDH1A2 expression.

Equol production capability and family history as risk factors for hand osteoarthritis in menopausal and postmenopausal women. Cross-sectional study.

BACKGROUND: Hand disorders are common in menopausal women. Equol is a soy metabolite produced in humans and its production level differs among individuals. The purpose of this research is to investigate the correlative relationship between variables indicating equol production levels and the occurrence of hand disorders in menopausal and postmenopausal women. METHODS: Female subjects were divided into two groups: women 45-70 years of age with hand osteoarthritis (patient group) and women in the same age range without hand osteoarthritis (control group). The equol production level of each subject was estimated by measuring her urine equol concentration. We also surveyed the subjects' family histories of osteoarthritis. RESULTS: Equol levels in the patient group were significantly lower than those in the control group (p < 0.05). This difference was most apparent for women in their 50s. Individuals with family histories of Heberden's and Bouchard's nodes were found to be 48.1 times more likely to develop these conditions than individuals in the control group. CONCLUSIONS: Women with early menopausal hand symptoms (i.e., stiff and arthritic hands) often develop hand osteoarthritis during their late menopausal and postmenopausal periods, which may cause their QoL to significantly deteriorate. Although a link between the probability of women developing hand osteoarthritis and their clinical backgrounds (i.e., family history) had been suspected, it had not been thoroughly investigated. Our survey of women with and without Heberden's nodes and Bouchard's nodes found a significant correlation between the likelihood of women developing osteoarthritis and a family history of this disease. We also found a significant correlation between the likelihood of women developing hand osteoarthritis and their equol production levels. These results indicate that women with family histories of finger osteoarthritis and low equol production have higher risks of developing finger osteoarthritis.

Surface replacing arthroplasty of a post-traumatic stiff and deviated proximal interphalangeal joint in an adolescent.

This case report describes the 4-year outcomes of proximal interphalangeal joint arthroplasty in a 14-year-old girl with a stiff joint after trauma. At follow-up, active range of motion was 35°, she was pain-free and satisfied with the outcome. Implant arthroplasty seems to be a valuable option for young patients with persistent post-traumatic stiff and deviated PIP joints to-at least temporarily-increase quality of life.

Circulating miRNAs in hand osteoarthritis.

OBJECTIVE: Hand osteoarthritis (OA) is a frequent musculoskeletal disorder with an increasing prevalence during ageing. This study aimed to evaluate circulating microRNAs (miRNAs) in the plasma of patients with hand OA compared with age- and sex-matched healthy control subjects. METHODS: In total, 238 participants (96 with erosive and 73 with non-erosive hand OA patients and 69 healthy control subjects) were included in this study. All patients underwent clinical examinations, including self-reported measures (AUSCAN and Algofunctional index). Radiographs of both hands were scored with the Kallman scale. The profile of miRNAs in plasma was screened using TaqMan™ Low-Density Array, and candidate miRNAs were validated on two quantitative real-time PCR (qRT-PCR) systems (QuantStudio and SmartChip). RESULTS: Of all the 754 miRNAs, 40 miRNAs were different between hand OA patients and healthy control subjects in the screening cohort. Following the two-phase validation process, three miRNAs (miR-23a-3p, miR-146a-5p, and miR-652-3p) were increased in patients with hand OA compared with healthy control subjects and were associated with the AUSCAN sum score and AUSCAN pain. Furthermore, an inverse correlation of miR-222-3p with the Kallman radiographic score was found. The expression of miRNAs did not differ between erosive and non-erosive hand OA. CONCLUSION: The profile of circulating miRNAs could unveil candidate biomarkers associated with hand OA symptoms. Longitudinal studies are required to determine the role of miRNAs in hand OA.

Serum tryptophan metabolites are associated with erosive hand osteoarthritis and pain: results from the DIGICOD cohort.

OBJECTIVE: To investigate host and gut-microbiota related Tryptophan metabolism in hand osteoarthritis (HOA). METHODS: The baseline serum concentration of 20 Tryptophan metabolites was measured in 416 HOA patients in a cross-sectional analysis of the DIGICOD cohort. Tryptophan metabolites levels, metabolite-ratios and metabolism pathway activation were compared between erosive (N = 141) and non-erosive HOA (N = 275) by multiple logistic regressions adjusted on age, BMI and sex. The association between Tryptophan metabolite levels and HOA symptoms was investigated by a Spearman's rank correlation analysis. RESULTS: Four serum Tryptophan metabolites, eight metabolite ratios and one metabolism pathway were associated with erosive HOA. Erosive HOA was negatively associated with Tryptophan (odds ratio (OR) = 0.41, 95% confidence interval [0.24-0.70]), indole-3-aldehyde (OR = 0.67 [0.51-0.90]) and 3-OH-anthranilic acid (OR = 1.32 [1.13-1.54]) and positively with 5-OH-Tryptophan levels (OR = 1.41 [1.13-1.77]). The pro-inflammatory kynurenine-indoleamine 2,3-dioxygenase pathway was upregulated in erosive HOA (OR = 1.60 [1.11-2.29]). Eleven metabolites were correlated with HOA symptoms and were mostly pain-related. Serotonin and N-acetyl serotonin levels were negatively correlated with number of tender joints. Indole-3-aldehyde level was negatively correlated and 3-OH-anthranilic acid, 3-OH-kynurenine and 5-OH-Tryptophan levels were positively correlated with number of patients-reported painful joints. Quinolinic acid and 3-OH-kynurenine levels correlated positively with AUSCAN pain. CONCLUSIONS: Tryptophan metabolites disturbance is associated with erosive HOA and pain and emphasize the role of low-grade inflammation and gut dysbiosis in HOA.

Associations between pain sensitization and measures of physical function in people with hand osteoarthritis: Results from the Nor-Hand study.

OBJECTIVE: To examine whether pain sensitization is associated with hand and lower extremity function in people with hand osteoarthritis (OA) in the Nor-Hand study. DESIGN: Pain sensitization was assessed by pressure pain thresholds (PPTs) and temporal summation (TS). Hand function was assessed by Australian/Canadian Osteoarthritis Hand Index (AUSCAN) (range: 0-36), grip strength and Moberg pick-up test, and lower extremity function was assessed by Western Ontario and McMaster Universities Osteoarthritis Index (range: 0-68), 30-s chair stand test, and 40-m walk test. We examined whether sex-standardized PPT and TS values were cross-sectionally associated with measures of physical function using linear regression analyses. Beta coefficients were presented per sex-specific standard deviation of PPT and TS. The mediating effect of pain was examined by causal-inference based mediation analysis. RESULTS: In 206 participants, higher PPTs at/near the hand, indicative of less peripheral and/or central pain sensitization, were associated with greater grip strength and better self-reported hand function (beta for PPT at finger joint on AUSCAN function: -1.41, 95% CI -2.40, -0.42). Higher PPTs at/near the hand, near the knee and at trapezius were associated with lower extremity function, although not statistically significant for all outcomes. Self-reported pain severity mediated the effect of PPT on self-reported function. TS was not associated with hand or lower extremity function. CONCLUSION: Peripheral sensitization, and possibly central sensitization, was associated with impaired function. Effects of PPTs on self-reported function were mediated by self-reported pain, whereas there might be a direct effect of sensitization or effects through other mediators on performance-based function.

Serum carboxymethyllysine concentration is associated with erosive hand osteoarthritis.

OBJECTIVE: Carboxymethyllysine (CML) and homocitrulline (HCit) are the products of two non-enzymatic post-translational modifications of protein, a process related to age. We investigated whether serum CML and HCit concentrations were associated with hand osteoarthritis (HOA), especially erosive HOA. DESIGN: Serum CML and HCit were measured by using liquid chromatography coupled with tandem mass spectrometry at inclusion in 386 patients included in the DIGItal Cohort Design (DIGICOD) cohort. We investigated whether serum CML and/or HCit concentrations were associated with erosive HOA or with HOA clinical and radiological features. Moreover, we compared the tissular concentrations of CML and HCit in OA and non-OA cartilage from proximal interphalangeal and metacarpo-phalangeal (MCP) joints from human cadaveric donors. RESULTS: Median (IQR) serum CML concentration was lower in patients with erosive HOA than those with non-erosive HOA (178.7 [157.1-208.8] vs 194.7 [168.9-217.1] µmol/mol Lys, P = 0.002), but median HCit concentration did not differ between the groups (193.9 [162.9-232.0] vs 193.9 [155.9-224.6] µmol/mol Lys). Cartilage HCit and CML concentrations were not correlated with clinical features. Serum CML concentration was higher in OA than non-OA MCPs (7.0 vs 4.0 mmol/mol Lys, P = 0.01). CONCLUSIONS: Serum CML concentration was lower in erosive HOA than non-erosive HOA, and cartilage CML concentration was higher in OA than non-OA cartilage. These results encourage further studies to test whether serum CML could be a new prognostic biomarker in HOA.

Serum biomarkers in prednisolone-treated hand osteoarthritis patients.

OBJECTIVES: To investigate whether biomarkers are modulated by prednisolone treatment in patients with hand OA and whether they can predict response to prednisolone. METHODS: Biomarkers reflecting tissue turnover and inflammation [aggrecanase-derived neoepitope of arggecan (ARGS), MMP-derived neoepitope of type I collagen (C1M), MMP-derived neoepitope of type III collagen (C3M), marker of true type V collagen formation (PROC5), MMP-derived neoepitope of CRP (CRPM), citrullinated vimentin fragment (VICM), high-sensitivity (hsCRP)] were measured in sera from 78 patients with painful inflammatory hand OA, who were randomized between prednisolone or placebo treatment. Association of baseline biomarker levels with disease characteristics [visual analogue scale (VAS) pain, synovial thickening ultrasonography sum score and erosive OA] and OMERACT-Osteoarthritis Research Society International (OARSI) response after 6 weeks were analysed with linear or logistic regression and adjusted for age, BMI and sex. Change in biomarker levels after 6 weeks was assessed with linear regression adjusted for baseline biomarker levels, age, BMI and sex. RESULTS: For all patients (mean age 64 years, 79% female), there were no associations between biomarker levels and VAS finger pain or synovial thickening score at baseline. Patients with erosive hand OA had higher levels of C1M and hsCRP [adjusted geometric mean ratio 1.24 (95% CI 1.03, 1.49) and 1.91 (1.19, 3.06), respectively]. Biomarker levels did not decrease over time. There was no association between baseline biomarkers levels and OARSI response, except for CRPM [geometric mean ratio of 0.88 (0.77, 1.00)]. CONCLUSION: Erosive disease was associated with higher levels of C1M and hsCRP. Biomarker levels were not influenced by treatment with prednisolone. Current biomarkers were not associated with response to prednisolone in hand OA.

Participation in healthcare consultations: A qualitative study from the perspectives of persons diagnosed with hand osteoarthritis.

INTRODUCTION: Scarce health resources and differing views between persons with hand osteoarthritis (OA) and health professionals concerning care preferences contribute to sustaining a gap between actual needs and existing clinical guidelines for hand OA. The aim of this study is to explore the experiences of persons diagnosed with hand OA in their encounters with health services and how those experiences influence negotiations and decision-making in hand OA care. METHODS: Data from 21 qualitative interviews with persons diagnosed with hand OA were collected, transcribed verbatim and analysed using reflexive thematic analysis. RESULTS: Three main themes were developed: symptoms are perceived as ordinary ageing in everyday life, consultations are shaped by trust in healthcare and the responsibilities of prioritisation and self-care govern interactions. CONCLUSION: Ideas of ageing, professional knowledge and self-management dominate hand OA health encounters and contribute to shaping illness perceptions, preferences and opportunities to negotiate decisions in consultations. PATIENT OR PUBLIC CONTRIBUTION: Two patient research partners with hand OA are members of the study project group. One of them is also a co-author of this manuscript.

Comparison of the cardiovascular risk profile of rheumatoid arthritis versus hand osteoarthritis patients.

It is clear that there is an increased cardiovascular (CV) risk in rheumatoid arthritis (RA) as a result of systemic inflammation. Hand osteoarthritis (HOA) patients, also have an increased CV risk, but the causes are still debated. Our objective was to compare CV risk factors and risk scores between HOA and RA patients. Thirty-five HOA patients were matched by age (< 3 years) and sex to 35 RA patients in a case-control study. We compared their CV risk profiles and their risk of occurrence of CV events at 10 years using the risk equations SCORE1, SCORE2, and QRISK3. There was a significant increase in SCORE1, SCORE2, but not in QRISK3 in the RA group compared to the HOA group, provided that the multiplication coefficient for RA was applied. This increase was found to no longer be significant for SCORE1 when RA patients have low disease activity (DAS28 ≤ 3.2; n = 8). There was no difference between groups in the frequency of metabolic syndrome, blood pressure, abdominal circumference, body mass index, uricemia, triglyceridemia, HDL cholesterolemia, or pain intensity. Conversely, HOA patients had higher LDL cholesterol and fasting blood glucose levels, in the main analysis and in the subgroup of moderate/high RA activity patients (DAS28 > 3.2; n = 26). We found a higher CV risk in RA compared to HOA patients with moderate/high disease activity. The increased CV risk reported in OA remains to be confirmed in HOA, but these patients appear to have a pro-atherogenic lipid and glycemic profile.

The BE-UJI hand function activity set: a reduced set of activities for the evaluation of the healthy and pathological hand.

BACKGROUND: Hand kinematics during hand function tests based on the performance of activities of daily living (ADLs) can provide objective data to determine patients' functional loss. However, they are rarely used during clinical assessments because of their long duration. Starting with the 20 Sollerman Hand Function Test (SHFT) tasks, we propose identifying a reduced set of ADLs that provides similar kinematic information to the original full set in terms of synergies, ranges of motion and velocities. METHODS: We followed an iterative method with the kinematics of 16 hand joints while performing the 20 ADLs of the SHFT. For each subject, ADLs were ordered according to their influence on the synergies obtained by means of a principal component analysis, the minimum number of ADLs that represented the original kinematic synergies (maximum angle of 30° between synergies), and the maintained ranges of joint movements (85% of the original ones) were selected for each subject. The set of the most frequently selected ADLs was verified to be representative of the SHFT ADLs in terms of motion strategies, ranges of motion and joint velocities when considering healthy subjects and Hand Osteoarthritis patients. RESULTS: A set of 10 tasks, the BE-UJI activity set, was identified by ensuring a certain (minimum) similarity in synergy (maximum mean angle between synergies of 25.5°), functional joint ranges (maximum differences of 10°) and joint velocities (maximum differences of 15°/s). The obtained tasks were: pick up coins from purses, lift wooden cubes, pick up nuts and turn them, write with a pen, cut with a knife, lift a telephone, unscrew jar lids and pour water from a cup, a jar and a Pure-Pak. These activities guarantee using the seven commonest handgrips in ADLs. CONCLUSION: The BE-UJI activity set for the hand function assessment can be used to obtain quantitative data in clinics as an alternative to the SHFT. It reduces the test time and allows clinicians to obtain objective kinematic data of the motor strategies, ranges of motion and joint velocities used by patients.

Burden of Hand Osteoarthritis in the Middle East and North Africa (MENA): An Epidemiological Analysis From 1990 to 2019.

PURPOSE: Hand osteoarthritis (OA) is a common cause of disability in older people. Although often underemphasized, it may affect quality of life and imposes a considerable burden on the health system. This study evaluated the epidemiology of hand OA in the Middle East and North Africa (MENA) region. METHODS: This epidemiological study was performed based on the Global Burden of Disease study from 1990 to 2019. The incidence, prevalence, and years lived with disability (YLD) in all 21 MENA countries during the study period were reported in rate, age-standardized, and percentage. RESULTS: Hand osteoarthritis in MENA increased 2.7-fold, from 1.6 million cases to 4.3 million from 1990 to 2019 with an age-standardized incidence rate of 50.2 (95% CI, 38.2-66.4) per 100,000 people in 2019. Saudi Arabia had the highest age-standardized prevalence in both 1990 (2.3%) and 2019 (2.3%), whereas Turkey had the lowest (0.3%) in both years. Total YLDs due to hand osteoarthritis increased by more than 2.7-fold, from 50,335 to 135,336 during the study period. The highest rate of increase in YLD rate from 1990 to 2019 was in Iran (3.3) and the largest decrease was in Qatar (-11.5). CONCLUSIONS: In contrast to the global trend, MENA hand OA prevalence and YLDs did not decrease between 1990 and 2019 and remained constant over time. Aging and increasing obesity rates, particularly among women, might be the contributing factors. Hand OA epidemiology varies by country, possibly due to genetic, ethnic, and environmental factors. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

Toward Early and Objective Hand Osteoarthritis Detection by Using EMG during Grasps.

The early and objective detection of hand pathologies is a field that still requires more research. One of the main signs of hand osteoarthritis (HOA) is joint degeneration, which causes loss of strength, among other symptoms. HOA is usually diagnosed with imaging and radiography, but the disease is in an advanced stage when HOA is observable by these methods. Some authors suggest that muscle tissue changes seem to occur before joint degeneration. We propose recording muscular activity to look for indicators of these changes that might help in early diagnosis. Muscular activity is often measured using electromyography (EMG), which consists of recording electrical muscle activity. The aim of this study is to study whether different EMG characteristics (zero crossing, wavelength, mean absolute value, muscle activity) via collection of forearm and hand EMG signals are feasible alternatives to the existing methods of detecting HOA patients' hand function. We used surface EMG to measure the electrical activity of the dominant hand's forearm muscles with 22 healthy subjects and 20 HOA patients performing maximum force during six representative grasp types (the most commonly used in ADLs). The EMG characteristics were used to identify discriminant functions to detect HOA. The results show that forearm muscles are significantly affected by HOA in EMG terms, with very high success rates (between 93.3% and 100%) in the discriminant analyses, which suggest that EMG can be used as a preliminary step towards confirmation with current HOA diagnostic techniques. Digit flexors during cylindrical grasp, thumb muscles during oblique palmar grasp, and wrist extensors and radial deviators during the intermediate power-precision grasp are good candidates to help detect HOA.

A Functional Polymorphism Downstream of Vitamin A Regulator Gene CYP26B1 Is Associated with Hand Osteoarthritis.

While genetic analyses have revealed ~100 risk loci associated with osteoarthritis (OA), only eight have been linked to hand OA. Besides, these studies were performed in predominantly European and Caucasian ancestries. Here, we conducted a genome-wide association study in the Han Chinese population to identify genetic variations associated with the disease. We recruited a total of 1136 individuals (n = 420 hand OA-affected; n = 716 unaffected control subjects) of Han Chinese ancestry. We carried out genotyping using Axiom Asia Precisi on Medicine Research Array, and we employed the RegulomeDB database and RoadMap DNase I Hypersensitivity Sites annotations to further narrow down our potential candidate variants. Genetic variants identified were tested in the Geisinger's hand OA cohort selected from the Geisinger MyCode community health initiative (MyCode®). We also performed a luciferase reporter assay to confirm the potential impact of top candidate single-nucleotide polymorphisms (SNPs) on hand OA. We identified six associated SNPs (p-value = 6.76 × 10-7-7.31 × 10-6) clustered at 2p13.2 downstream of the CYP26B1 gene. The strongest association signal identified was rs883313 (p-value = 6.76 × 10-7, odds ratio (OR) = 1.76), followed by rs12713768 (p-value = 1.36 × 10-6, OR = 1.74), near or within the enhancer region closest to the CYP26B1 gene. Our findings showed that the major risk-conferring CC haplotype of SNPs rs12713768 and rs10208040 [strong linkage disequilibrium (LD); D' = 1, r2 = 0.651] drives 18.9% of enhancer expression activity. Our findings highlight that the SNP rs12713768 is associated with susceptibility to and severity of hand OA in the Han Chinese population and that the suggested retinoic acid signaling pathway may play an important role in its pathogenesis.