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ID PMID Title PublicationDate abstract
19307756 Polymorphisms of COTL1 gene identified by proteomic approach and their association with au 2009 May 31 To select candidate genes, we attempted to comparative analysis of protein levels between rheumatoid arthritis (RA) patients and healthy controls by two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF-MS). We identified 17 proteins that showed up- or down-regulated spots in RA patients. We found that coactosin-like1 (COTL1) were highly expressed in RA patients compared with healthy controls. We performed a case-control study to determine whether the COTL1 gene polymorphisms were associated with RA and systemic lupus erythematosus (SLE). The genotype frequency of c.-1124G>T and the allelic frequency of c.484G>A in RA patients, and the genotype frequency of c.484G>A in SLE patients were significantly different from healthy controls (P=0.009, 0.027, and 0.025, respectively). We also investigated the correlation with the levels of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (CCP) antibody in RA patients, and anti-nuclear antibodies (ANA) in SLE patients. The c.484G>A polymorphism in RA patients has significant association with the levels of anti-CCP antibody (P=0.03). Our findings demonstrated that c.-1124G>T and c. 484G>A polymorphisms of the COTL1 gene might be associated with the genetic susceptibility of autoimmune disorders.
19509325 Clinical implications of understanding radiographic findings in relation to clinical outco 2009 Jun The clinical progression of rheumatoid arthritis (RA) and longterm response to therapy is generally assessed by quantifying changes in joint space narrowing and erosions visible on serial plain radiographs. In patients treated with classic disease modifying antirheumatic drugs, the joint damage seen on radiographic images is usually directly associated with longterm functional disability. However, this relationship is not as clearly defined in patients treated with biologic agents. The apparent dissociation between clinical and radiologic outcomes in patients with RA who are treated with biologic therapies needs to be taken into consideration when evaluating the efficacy of treatment.
19561156 Ultrasonographic evaluation of joint involvement in early rheumatoid arthritis in clinical 2009 Sep OBJECTIVES: This study aimed to evaluate the usefulness of a systematic musculoskeletal ultrasonographic (US) assessment in the detection of residual disease activity in patients with early RA who achieved clinical remission. METHODS: We prospectively studied 106 early RA patients receiving conventional DMARDs according to a disease activity score (DAS)-steered therapeutic protocol over a 24-month period. Standard evaluation included clinical, laboratory, functional and systematic (44 joints) US assessment. US indexes of grey scale (GS) and power Doppler (PD) synovitis were correlated with clinical evaluation, laboratory indexes and clinical outcome. Clinical remission was defined when DAS was <1.6 at two consecutive visits 3 months apart. RESULTS: US examination was significantly more sensitive than clinical examination, both in active disease and in remission. In patients with an active disease, both clinical and US indexes correlated with CRP, whereas in remission only PD still remained significantly correlated. In clinical remission, 95% of the patients showed residual GS synovitis, and 41% of them showed a positive PD signal. Positive PD signal, even in a single joint, resulted the main predictor of relapse within 6 months, both in univariable and multivariable logistic regression analysis. CONCLUSIONS: In a cohort of early RA patients treated with conventional DMARDs, US-GS can detect residual disease activity more sensitively than clinical examination both in active disease and in remission. Moreover, PD-positive synovial hypertrophy identifies an ongoing inflammation even during remission and predicts short-term relapse.
19365265 What happens before the onset of rheumatoid arthritis? 2009 May PURPOSE OF REVIEW: To give an overview of publications on presence of autoantibodies, rheumatoid factor and anticitrullinated protein/peptide antibodies (ACPAs) and their relationships to genetic markers and soluble factors as indicators of immune activation and identified predating the onset of symptoms of rheumatoid arthritis (RA). RECENT FINDINGS: The development during recent years concerning autoantibodies with high specificity for RA, ACPAs, has confirmed previous findings of presence of autoantibodies, such as rheumatoid factors and antikeratin antibodies, years before disease onset. Particularly, ACPAs in combination with human leukocyte antigen-shared epitope alleles and PTPN22 1858T carriage increased the relative risks of developing RA compared with not having these factors. Both shared epitope alleles and 1858T variant seemed to contribute to development of ACPAs rather than independently contribute to RA. Soluble factors such as hypersensitive C-reactive protein, cytokines, cytokine receptors and chemokines are upregulated before disease onset, though, not as long antedating time as ACPAs and rheumatoid factors. SUMMARY: Presence of ACPAs and rheumatoid factors are present several years before disease onset suggesting a gradual process leading to the development of RA. Genetic markers such as shared epitope alleles and PTPN22 1858T variant increase the relative risk for disease development. Soluble immunological markers are also increased closer to the onset of symptoms indicating activation of the immune system.
20047520 Programmed cell death 5 factor enhances triptolide-induced fibroblast-like synoviocyte apo 2010 OBJECTIVE: To study the effect of programmed cell death 5 (PDCD5) on apoptosis of rheumatoid arthritis fibroblast-like synoviocyte (RAFLS) induced by triptolide. METHOD: Cultured synovial cells in vitro from RA patients were transfected with Ad-PDCD5. In protein level, expression of PDCD5 protein in Ad-PDCD5 transfected RAFLS was detected by Western blot. RAFLS transfected with Ad-PDCD5 were cultured in presence or absence of triptolide and RAFLs apoptosis was determined by flow cytometry. RESULT: Transfection of RAFLS with increasing concentration of Ad-PDCD5 (50-300 MOI) resulted in dose-dependent increase of PDCD5 production. Apoptotic cells percentage of no transfection group, Ad-null group and Ad-PDCD5 group were, respectively, (22.41 +/- 3.87)%, (28.77 +/- 12.97)%, and (48.87 +/- 12.69)%. Alternatively, transfection without triptolide stimuli had no effect. The data showed that gene transfection of PDCD5 alone without triptolide was not sufficient to activate RAFLS apoptosis; PDCD5 acted as an enhancer rather than inductor of apoptosis. CONCLUSION: Overexpression of PDCD5 could enhance apoptosis of RA FLS induced by triptolide; PDCD5 may be a potential therapeutic target to RA.
21088968 [Biomarkers collections: the future or a waste of resources?]. 2010 Dec Disease biomarkers would aim at a more specific definition of diagnosis or subtype of a certain disease, as well as prognosis definition, including efficacy and side effects of certain therapeutics. Biomarkers could lead to a prognostically optimized definition of remission in the individual patient and thus to a more objective definition of therapeutic efficacy. Is this possible and does it make sense? Or would an extensive analysis of biomarkers to date lead to a costly overestimation of as yet not well established biologic parameters? Although we are currently unable to answer this question, many colleagues argue in favour of more in depth research for a better evaluation of biomarkers in many diseases. This could save money if we were able to predict the efficacy of expensive drugs such as immunobiologics. Biomarkers comprise cytometric information, data on protein expression and secretion, mRNA, microRNA or DNA, including epigenetic variants. Although much of these data already exist in the scientific literature, it is associated with problems in terms of feasibility (for cytometry and RNA analysis only on-site analysis is possible, while for DNA analysis central testing is also possible), costs and reproducibility (ethnic variability!). To date all biomarkers have only limited value in terms of the above-mentioned aims. The present review compiles "PROs and CONs" in a subjective way in order to provoke a discussion on the meaningfulness of biomarkers, while at the same time supporting and encouraging further research in this field.
19822066 Biologics in the treatment of rheumatoid arthritis and ankylosing spondylitis. 2009 Jul There are clear differences in the clinical picture and in the pathogenesis between rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Biologic agents targeting TNF-alpha are efficacious in both diseases, with some tendency to work even better in spondyloarthritides (SpA) on a clinical basis. However, anti-TNF therapy was shown to inhibit radiographic progression in RA but not in AS. This is probably due to the outstanding difference in pathogenesis: while in RA osteodestructive lesions such as erosions predominate, AS patients will rather develop osteoproliferative changes such as syndesmophytes. There is some evidence that anti-TNF agents may show longterm efficacy and acceptable safety profiles over 5-10 years. There are some differences between the agents.Whether the recent developments of targeted therapies in RA with agents such as rituximab, abatacept and tocilizumab will also work for AS is unknown at present.
19847085 The prevalence and diagnostic performance of anti-cyclic citrullinated peptide antibody in 2009 Nov BACKGROUND AND OBJECTIVES: The utility of anticyclic citrullinated peptide (anti-CCP) antibody in the diagnosis of rheumatoid arthritis (RA) varies across different studies. We determined the diagnostic performance and predictive ability of anti-CCP for RA. METHODS: We studied 201 patients with RA and compared them with 208 non-RA patients as controls. RA patients included in the study fulfilled the American College of Rheumatology revised criteria and patients with other diseases as well as those with undifferentiated arthritis (UIA) were used as controls. Anti-CCP was measured by enzyme-linked immunosorbent assay (ELISA) and rheumatoid factor (RF) by the agglutination method. The optimal cutoff value and diagnostic accuracy were determined using receiver operating characteristics (ROC) curve and area under the curve (AUC).The sensitivity and specificity were determined by comparison of RA patients with non-RA controls. RESULTS: The anti-CCP test was positive in 164 patients with RA for a sensitivity of 81.6%, specificity of 87.5%, and overall accuracy of 84.6%. The respective values for RF were 75.6%, 86.5% and 84.4%. The anti-CCP test discriminated RA from non-RA patients with high accuracy (AUC=0.889 [0.017] 95% CI, 0.856-0.952, P=.001), and predicted progression of UIA to RA with moderate accuracy (AUC=0.733 [0.069], 95% CI 0.60-0.87, P<.006) at a sensitivity of 75% and a specificity of 68.1%. Among 60 UIA patients, in 16 (26.7%) who differentiated to RA, the mean (standard deviation) for anti-CPP was significantly higher than in 24 (40%) patients who progressed to non-RA (134.8 [172] vs 46 [86] U/mL, P<.01). CONCLUSION: These findings indicate that anti-CCP yields higher sensitivity and overall accuracy, but slightly greater specificity than RF for diagnosis of RA. Anti-CCP positivity, particularly a higher level of serum antibody in patients with UIA, may be a predictor of subsequent RA.
20192990 Antibodies to citrullinated proteins: molecular interactions and arthritogenicity. 2010 Jan The discovery of antibodies specific for citrullinated protein epitopes [anti-citrullinated protein antibodies (ACPAs)] is a hallmark for the diagnosis and prognosis of rheumatoid arthritis (RA) and will also be a useful tool for understanding the fundamental pathologic processes. There are several essential questions pertaining to ACPA that remain to be explored, such as understanding the early specificity of the underlying T-cell recognition, whether the production of ACPA is a primary or secondary process, and in the event of such antibodies being arthritogenic, whether they could possibly regulate the disease development. To answer these questions, animal models are needed, but unfortunately ACPA is not a prominent feature of any of the classical animal models of RA. However, we showed recently that ACPA can be isolated from animals susceptible to collagen-induced arthritis that are specific for citrullinated type II collagen (CII). The citrulline specificity could be visualized, and the specificity is determined primarily by a direct interaction with citrulline. We also demonstrated that these antibodies are specific for the citrullinated epitopes and are pathogenic in vivo. A new hypothesis to explain how inflammation in RA can be directed to cartilaginous joints and be self-perpetuating is suggested, which involves recognition of post-translational modifications (glycosylation and citrullination) on CII by T and B cells that can have both arthritogenic and regulatory consequences.
19828917 Assessment of objective and subjective quality of life in people with rheumatoid arthritis 2009 Jul BACKGROUND: Quality of life evaluation is nowadays an important element in the assessment of treatment and rehabilitation effectiveness in people with rheumatoid arthritis (RA). According to studies of patients with other diseases, objective indicators of life quality are not directly related to the level of subjective life satisfaction. Both dimensions should be taken into account in a reliable evaluation of the quality of life of any patient. The analysis of available literature reveals few publications concerned with evaluating quality of life in people with RA in both the objective and subjective dimensions. MATERIAL AND METHOD: A total of 42 people with RA took part in the study. The Life Satisfaction Questionnaire was used to assess subjective quality of life, and the objective dimension was assessed with a questionnaire investigating education, employment, income etc., before and after the disease was diagnosed. RESULTS: The study found that people with RA perceive their global life satisfaction as low. Only 38% of the participants were satisfied with their lives as a whole. Their vocational activity decreased by more than 45% in relation to the situation before developing RA. Watching TV was the most often stated leisure activity. People with RA were most satisfied with their family life and contact with friends, and the least satisfying life domains were their vocational and financial situations. The main predictors of global life satisfaction in people with RA were satisfaction with the financial situation and sexual life. CONCLUSION: RA decreases both the objective and subjective dimensions of quality of life. Taking into account the importance of patient quality of life evaluation in the assessment of effectiveness of treatment and rehabilitation in patients with RA, it seems necessary to include both dimensions, as only this guarantees achieving results that reliably reflect the real situation.
19755617 Test-retest reliability of patient global assessment and physician global assessment in rh 2009 Oct OBJECTIVE: As a guide to treatment of rheumatoid arthritis (RA), physicians use measurement tools to quantify disease activity. The Patient Global Assessment (PGA) asks a patient to rate on a scale how they feel overall. The Physician Global Assessment (MDGA) is a similar item completed by the assessing physician. Both these measures are frequently incorporated into other indices. We studied reliability characteristics for global assessments and compared test-retest reliability of both the PGA and the MDGA, as well as other commonly used measures in RA. METHODS: We studied 122 patients with RA age 17 years or older. Patients who received steroid injection or change in steroid dose at the visit were excluded. Patients completed the HAQ, PGA, visual analog scale for pain (VAS Pain), VAS Fatigue, and VAS Sleep. After seeing their physician, they received another questionnaire to complete within 2 days at the same time of day as clinic visit. Physicians completed the MDGA at the time of the patient's appointment and at the end of their clinic day. Test-retest results were assessed using intraclass correlations (ICC). "Substantial" reliability is between 0.61-0.80 and "almost perfect" > 0.80. RESULTS: Four rheumatologists and 146 patients participated, with 122 questionnaires returned (response rate 83.6%). Test-retest reliability was 0.702 for PGA, 0.961 for MDGA, and 0.897 for HAQ; VAS results were 0.742 for Pain, 0.741 for Fatigue, and 0.800 for Sleep. The correlation between PGA and MDGA was -0.172. CONCLUSION: PGA, MDGA, HAQ, and VAS Pain, VAS Fatigue, and VAS Sleep all showed good to excellent test-retest reliability in RA. MDGA was more reliable than PGA. The correlation between PGA and MDGA was poor.
20350799 Indolent infectious tenosynovitis afflicting rheumatoid patients treated with tumor necros 2010 Jun Tumor necrosis factor (TNF) is a cytokine associated with the pathogenesis of rheumatoid arthritis. Tumor necrosis factor inhibitors have become important biological treatments that favorably alter the natural history of rheumatoid disease. Side effects include an increased risk of malignancy and infection, particularly tuberculosis. We present 2 patients with rheumatoid arthritis on TNF inhibitors in whom flares of wrist tenosynovitis, initially diagnosed as rheumatoid disease exacerbations, were caused by infections with uncommon opportunistic pathogens. Diagnostic and treatment recommendations for this subset of rheumatoid patients are discussed.
21137052 Is GRP78/BiP a potential salivary biomarker in patients with rheumatoid arthritis? 2010 Mar PURPOSE: In the last few years, serum and joint synovial fluid have been extensively analyzed for the proteomic research of rheumatoid arthritis (RA) biomarkers. Nonetheless, to date, there have been no studies investigating salivary biomarkers in this condition. Therefore, aim of this study is to investigate the presence of potential biomarkers of RA in human whole saliva. EXPERIMENTAL DESIGN: We combined 2-DE and MS to analyze the whole saliva protein profile of 20 RA patients in comparison with 20 sex- and age-matched healthy subjects. RESULTS: Eight salivary proteins resulted differentially expressed, namely calgranulin A, calgranulin B, apolipoprotein A-1, 6-phosphogluconate dehydrogenase, peroxiredoxin 5, epidermal fatty acid-binding protein, 78 kDa glucose-regulated protein precursor (GRP78/BiP), and 14-3-3 proteins. It is particularly interesting that chaperone GRP78/BiP showed the greatest increase in RA patients. This finding was validated by Western Blot analysis and the over-expression of GRP78/BiP appear to be distinctive of RA and drugs treatment independent. CONCLUSIONS AND CLINICAL RELEVANCE: This study provides a rationale for further studies aimed at evaluating any correlation between GRP78/BiP and different clinical/serological aspects of the disease in order to improve the diagnostic algorithms of RA.
19015209 Early occupational therapy programme increases hand grip strength at 3 months: results fro 2009 Mar AIM: The goal of occupational therapy (OT) is to facilitate adjustments to lifestyle and to prevent function loss. This study evaluated the effects of an early OT programme in early rheumatoid arthritis (RA). METHODS: We conducted a randomised, blind, controlled trial enrolling 60 patients with early RA, divided into 2 groups. At baseline, group 1 received the full information programme and group 2 received no information. In an extension phase, patients in group 2 received the full information programme at 3 months and were assessed at 6 months. The main outcomes were grip strength of hands (as objective assessment) and Health Assessment Questionnaire (HAQ) score (as subjective assessment). RESULTS: At 3 months, grip strength of the dominant and non-dominant hands increased more in group 1 than in group 2 (p = 0.021 and 0.047 respectively). HAQ score decreased more in group 1 than in group 2 (p<0.001). In the extension phase, changes in grip strength and HAQ score in group 2 were similar to those seen in group 1 between baseline and 3 months. CONCLUSIONS: This study comparing two schedules of OT programme showed that an early extended information programme improved hand function in patients with early RA.
19284361 Treatment strategies for a patient with rheumatoid arthritis and hepatitis C. 2009 Mar BACKGROUND: The poor prognosis of rheumatoid arthritis (RA) can be aggravated by the concomitant presence of chronic hepatitis C virus (HCV) infection and there are no guidelines for the treatment of patients affected by both conditions. OBJECTIVE: To propose new therapeutic strategies for patient affected by RA and concomitant HCV chronic infection. METHODS: Review of the literature on the usage of cyclosporine-A (CsA) and anti-tumour-necrosis-factor (TNF)-alpha agents for the treatment of patients affected by RA and HCV. RESULTS/CONCLUSION: CsA exerts an inhibitory effect on HCV replication and it is safe in patients affected by RA and HCV. Anti-TNF-alpha agents are safe and efficacious in patient with RA and HCV. Anti-TNF-alpha and CsA can be safely given in combination in RA patients with HCV infection.
19772784 Disease activity assessment of rheumatoid arthritis in daily practice: validity, internal 2009 Jul OBJECTIVE: The Disease Activity Score including 28 joints (DAS28) and the Clinical Disease Activity Index (CDAI) were developed in order to provide a quantifiable measure of rheumatoid arthritis (RA) activity. The aim of this study was to evaluate the validity and internal consistency reliability for DAS28 and CDAI in patients with RA seen by rheumatologists in usual clinical care. We also compared proposed categories of high, moderate, and low activity and remission according to both scores. PATIENTS AND METHODS: A sample of 2864 RA patients (2267 female, 597 male; mean age 58.5 yr, range 18-88 yr) were enrolled in this cross-sectional community-based study. Disease activity was assessed in each patient based on DAS28 and CDAI. Patients completed the Health Assessment Questionnaire (HAQ). Statistical evaluation was carried out by applying the Cronbach's values and principal component analysis (internal consistency reliability), the Pearson's coefficients, ANOVA and kappa statistic (convergent validity) and receiver operating characteristic (ROC) curve analysis (discriminant validity). RESULTS: Internal consistency testing of both scores indicated a reasonable difference, with Cronbach's alpha slightly higher for the DAS28. Interestingly, factor analysis revealed that the DAS28 constitutes a monocomponent measure in RA. Linear regression analysis showed a significant correlation between DAS28 and CDAI (p<0.0001). In addition, the DAS28 and CDAI were well correlated with HAQ (both at p level of <0.0001). The discriminatory power of both indices was good, without significant difference, but our results showed wide differences in both moderate/high disease activity and remission percentages (k=0.418). CONCLUSIONS: DAS28 and CDAI are valid and simple acceptable ways to measure RA activity in the clinical practice, but disease activity categorized by these indices differ considerably. Further research is needed to resolve this issue.
21199474 Prevalence of rheumatoid arthritis in the eastern Black Sea region of Turkey. 2010 Oct AIM: The aim of this study was to estimate the prevalence of rheumatoid arthritis (RA) in the eastern Black Sea region of Turkey. METHOD: The study was carried out between March 2003 and March 2005 by the Karadeniz Technical University Medical Faculty Department of Physical Medicine and Rehabilitation in the urban area in the eastern Black Sea region of Turkey, which has a population of 459021 (according to the 2000 national census). A total of 6103 subjects, 20 years old or over, were selected by the sampling method; 3023 (49.5%) women and 3080 (50.5%) men were included in the study. The diagnosis of RA was performed based on fulfilling the American College of Rheumatology (ACR) criteria. RESULTS: Fifty-nine patients were diagnosed with RA according to the ACR criteria, of which 11 were male and 48 female. The prevalence of RA was 1% (95% CI: 0.75-1.25) in the general population, 1.6% (95% CI: 1.15-2.05) in women and 0.35% (95% CI: 0.14-0.56) in men. The female/male ratio was 4.3 : 1.0, showing that RA prevalence was statistically significantly higher in women (P <0.005). CONCLUSION: Our study demonstrates that RA is a common disease in Turkish society.
18946808 Influence of foot orthoses on plantar pressures, foot pain and walking ability of rheumato 2009 PURPOSE: To compare the effectiveness of functional foot orthoses and unshaped (flat) orthotic material on plantar pressure redistribution, forefoot pain reduction and walking ability in rheumatoid arthritis (RA) patients. METHODS: Forty patients with RA were randomised to receive unshaped material (UM) (n = 20) or functional foot orthoses (n = 20). Plantar pressure measurement was performed with an F-scan system. Foot pain was assessed by the pain subscale of the Foot Function Index. Walking ability was assessed by the 6-min walking test. Investigations were performed at baseline, 1 week after the patient received shoes with orthoses and 6 months later. RESULTS: Plantar pressures were significantly higher at painful than at non-painful foot areas. No differences in plantar pressure redistribution were found between the groups. Notable reduction of pain and improvement of activity (walking ability) was observed in both groups. Foot pain has moderate impact on the walking ability of RA patients. CONCLUSIONS: The study showed no clear advantage of functional foot orthoses over UM.
19822057 Cost-of-illness of rheumatoid arthritis and ankylosing spondylitis. 2009 Jul OBJECTIVE: To assess, quantify and summarise the cost of illness of rheumatoid arthritis (RA) and ankylosing spondylitis (AS) from the societal perspective. METHODS: Original studies reporting costs of RA or AS were searched systematically. Both cost-of-illness studies and economic evaluations of therapies were included. Studies were appraised for patient and study characteristics, type of costs and actual costs. Reported costs were aggregated by cost categories and overall mean costs were summarised by cost domain (healthcare, patient and family, and productivity costs). RESULTS: Overall mean costs of RA (euro14,906 per year) were above that of AS (euro9,374 per year), while the relative distribution of costs over cost domains was approximately similar. For both diseases, productivity costs based on the human cost approach were 3 to 10 times higher than the friction costs and accounted for more than half the total costs of both diseases. CONCLUSION: Productivity costs constitute the largest part of the total cost-off-illness of RA and AS reflecting the high burden of the disease on work participation. Although total and direct costs of illness in RA were higher than in AS, the average age of AS patients was 10 years lower and therefore, lifetime costs associated with AS may actually be equal or higher.
19516084 Digigait quantitation of gait dynamics in rat rheumatoid arthritis model. 2009 Apr INTRODUCTION: Rheumatoid arthritis (RA) is characterized by joint pain, allodynia and hyperalgesia. The rat carrageenan model utilizes inflammation-associated pain following injection of the knee joint to model RA. Traditional assessment of pain in these models utilizes behavioral scoring or manual measurements, methods that are labor intensive and prone to subjective interpretation. This study utilizes the Digigait system to objectively quantify movement and gait dynamics in a monoarthritic rat model. MATERIAL AND METHODS: A pilot study in rats selected "natural" runners using Digigait, and also measured inter and intraday variability as well as effects of anesthesia on gait dynamics. In the main study, 12 female rats were tested at baseline, divided in two groups of 6 rats, briefly anesthetized with isoflurane and injected with 60 microl of 2% lambda carrageenan or vehicle; Digigait testing was repeated 2 and 4 hours post injection and data analyzed. RESULTS: Selection of "natural" runners significantly contributed to accuracy and reproducibility of gait parameters obtained by the Digigait system. There was minimal intra and inter day variation between individual rats and 4 minutes of isoflurane anesthesia had no effect on gait dynamic at 2 and 4 hours post administration. In the main study a highly reproducible gait signature in the injected limb, and well coordinated adaptation of gait during locomotion in the non-affected limbs were noted as short-term changes following carrageenan injection. CONCLUSION: Digigait system was found to be an objective and reliable method for quantification of early behavioral changes consistent with allodynia and hyperalgesia in an inflammatory pain model.