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ID PMID Title PublicationDate abstract
20872985 Case report: Infliximab treatment in two Chinese patients with psoriatic arthritis. 2010 Oct Psoriatic arthritis (PsA) is a rheumatoid factor (RF)-seronegative systemic inflammatory disorder associated with psoriasis. Current treatment for PsA in China is still focused on disease modifying anti-rheumatic drugs (DMARDs). In this paper, we report two Chinese patients with active longstanding PsA treated with infliximab, a human-mouse chimeric monoclonal antibody against tumor necrosis factor alpha (TNF-α). The results show that infliximab acted quickly and effectively in relieving peripheral and axial symptoms and refractory skin lesions, even in recombinant human TNF-α receptor (rhTNFR)-resistant case. The take-home message from our cases is that infliximab is a useful therapeutic option for refractory PsA, especially when a patient has a combination of psoriasis and psoriatic arthritis. Further local evidence and experience must be accumulated in order to make anti-TNF-α therapy more accessible to PsA patients in China.
20223159 [Leishmaniasis and rheumatoid nodulosis in a patient with HIV infection]. 2010 Mar We describe the case of a 44-year-old homosexual man diagnosed with HIV infection and visceral leishmaniasis. He presented nodules on the dorsum of the hands. Histological study of one of the nodules revealed necrobiotic palisading granulomas with abundant Leishmania amastigotes within the histiocytes and in the adjacent extracellular space. Tissue and peripheral blood cultures were positive for Leishmania infantum, zymodeme MON-24. A biopsy of healthy skin did not reveal the presence of Leishmania. A diagnosis of rheumatoid nodulosis with Leishmania was made and treatment was started with intravenous liposomal amphotericin, leading to slight improvement. We believe that the presence of the parasite within the nodules was the result of its dissemination during visceral leishmaniasis in an immunocompromised patient with HIV infection, and that the Leishmania did not have an etiological role in the appearance of the nodules. We present the first case of the association between Leishmania and rheumatoid nodulosis.
20123387 A comparison of diagnostic tools for Sjögren syndrome, with emphasis on sialography, hist 2010 Jan OBJECTIVE: The present study examined the reliability and correlation of sialography, salivary gland biopsy, and ultrasonography for Sjögren syndrome (SS) and evaluated the usefulness of ultrasonography as a diagnostic tool for SS compared with sialography and histopathology. STUDY DESIGN: Seventy-three patients who underwent sialography, ultrasonography, and salivary gland biopsy were included in this study. The study evaluated the diagnostic reliability and correlation of each kind of examination with SS. RESULTS: There was a statistically significant difference in the sensitivities of sialography and histopathology, in the specificities of sialography and ultrasonography, and in the accuracies of sialography and both ultrasonography and histopathology. The correlation coefficient (r) between sialography and ultrasonography was significantly higher than the others and indicated a good correlation. CONCLUSIONS: Ultrasonography can be used as a diagnostic tool for SS, with its advantage of noninvasiveness and ease of use.
19407023 The role of fractalkine as an accelerating factor on the autoimmune exocrinopathy in mice. 2009 Oct PURPOSE: Sjögren's syndrome (SS) is an organ-specific autoimmune disease caused by the progressive loss of exocrine glands and is associated with several autoimmune phenomena. Various research studies have been performed, and many molecules have been suggested as responsible for the pathogenesis of SS. Here the authors show the increased expression of fractalkine (CX(3)CL1) in lacrimal glands of SS model mice. Among more than 50 known chemokines, fractalkine is the sole member of the CX(3)C family and has unique structural and functional attributes. The purpose of this study was to analyze the role of fractalkine in exocrine glands. METHODS: The expression of fractalkine in the lacrimal glands of thymectomized NFS/sld mice was investigated by immunohistochemistry and RT-PCR. To confirm the effects of fractalkine in exocrine glands, tissue-specific fractalkine transgenic mice were generated using the salivary amylase promoter. RESULTS: The results demonstrated the upregulated fractalkine expression in thymectomized NFS/sld mice. Furthermore, the lacrimal and salivary gland-specific fractalkine transgenic mice showed the expression of fragmented fractalkine and lymphocytic infiltration in their lacrimal and submandibular glands. Interestingly, the dominant population was B cells in the lacrimal glands, whereas B cells and CD4(+) T cells were infiltrated in the submandibular glands. These mice also demonstrated slightly decreased tear and salivary secretion compared with wild-type mice. CONCLUSIONS: Based on these results, it may be that fractalkine contributes to the development of SS, especially in lymphocyte migration to exocrine glands, and that it accelerates the disease in association with other molecules.
19008012 Adult onset Still's disease after first cycle of pemetrexed and gemcitabine for non-small 2009 Apr Pemetrexed is a multitargeted antifolate approved for the second-line treatment of locally advanced or metastatic non-small cell lung cancer. The combination of pemetrexed with gemcitabine has been studied in several clinical trials showing a promising antitumor activity with a mild toxicity profile. We present the case of a patient who experienced fever, arthralgia, skin rash and high serum ferritin levels after first cycle of this chemotherapy combination, compatible with an adult onset Still's disease. This adverse event has not been previously reported.
19181658 Association of killer cell immunoglobulin-like receptors with primary Sjogren's syndrome. 2009 Apr OBJECTIVE: SS is a chronic inflammatory condition characterized by systemic and tissue-specific autoimmune features. In view of recent findings indicating a role for killer cell immunoglobulin-like receptors (KIRs) in the pathogenesis of other autoimmune rheumatic disorders such as SSc, and the autoimmune disorders RA and PsA, we sought to determine whether KIRs predict general or specific susceptibility in SS. METHODS: Eleven separate KIR genes were typed using PCR sequence-specific primers on genomic DNA from 72 patients diagnosed with primary SS and a control panel consisting of 223 blood donors. RESULTS: We found no individual KIR genes to be associated with SS. In contrast, 11 patients with primary SS (15%) and 9 control blood donors (4%) had KIR genotypes with the activating KIR2DS2 in the absence of its corresponding inhibitory homologue KIR2DL2 (P = 0.01). Further analysis of these individuals showed that seven SS patients were positive for HLA-C ligand for KIR2DS2 only compared with one control sample (P = 0.00026). CONCLUSION: The genetic combination of KIR2DS2+ and KIR2DL2- in the presence of HLA-C ligand specific for activating KIR2DS2 is associated with primary SS. This implies that autologous KIR-ligand interaction is a contributory factor to predisposition for this disease.
19115058 Cloak and dagger: the case for adult onset still disease and hemophagocytic lymphohistiocy 2009 Jun Adult onset Still's disease (AOSD) is a rare systemic inflammatory disorder of unknown etiology. Systemic onset juvenile idiopathic arthritis (SoJIA) is the preferred nomenclature of Still's disease. Strong association with so-called macrophage activation syndrome (MAS) may provide a clue to the understanding of the distinctive pathogenetic features of SoJIA. MAS is a severe, potentially life-threatening complication characterized by the excessive activation of well-differentiated macrophages. It is more appropriately named autoimmune disease associated reactive hemophagocytic lymphohistiocytosis (ReHLH), a subset of a histiocytic disorder: class II histiocytosis hemophagocytic lymphohistiocytosis (HLH). The relation of SoJIA with HLH is still under debate. We propose that MAS, HLH, SoJIA, and AOSD are indeed the same disease, in different clinical presentations that may be classified based on severity and laboratory findings, but with essentially the same physiopathogenesis. We propose that the case described by Hong & Lee (Rheumatol Int 2008) was actually an AOSD-associated MAS/RHS/ReHLH fulminant disease.
19764519 [A case of Sjögren syndrome with pulmonary nodular amyloidosis and pulmonary multiple cys 2009 Aug A 57-year-old woman who had been given a diagnosis of Sjögren syndrome at age 53 consulted a nearby doctor because of bloody sputum. He noted her chest abnormal shadows and referred her to our hospital. Her chest radiograph and high-resolution computed tomograph showed multiple nodules and cysts in both lung fields. Video-assisted thoracoscopic lung biopsy revealed patchy fibrosis, cystic change, AL type amyloid deposition and mild lymphoid hyperplasia and a diagnosis of Sjögren syndrome-associated-pulmonary-disease was established.
18422594 Prevalence of primary Sjogren's syndrome in Turkey: a population-based epidemiological stu 2009 Jun OBJECTIVES: The aim of this study was to determine the prevalence of primary Sjogren's syndrome (pSS) in a general Turkish population according to the latest proposed American-European Consensus Group (AECG) criteria and European-1 (EU-1) criteria. METHODS: The study was conducted in two districts of Izmir and involved 2835 subjects 20 years of age and older. In the first stage, face-to-face interviews were performed at the registered households. In the second stage, subjects reporting symptoms of both dry eye and dry mouth were invited to the hospital for a full examination, which included Schirmer-1, sialometry and serologic tests. In the third stage, a minor salivary gland biopsy was performed as required. RESULTS: A total of 2887 subjects were contacted and a complete interview was obtained for 2835 (1551 female, 1284 male) subjects. A total of 159 subjects (126 female, 33 male) confirmed oral and ocular dryness, and 86 of these patients (54.1%) underwent a detailed clinical examination in the hospital. pSS was diagnosed in 10 patients (nine females) according to the EU-1 criteria, and in six patients (six females) according to the AECG criteria. We found a minimum crude prevalence of 0.21% [95% confidence interval (CI): 0.03-0.29] in the sample population and an age-sex adjusted prevalence of 0.16% (95% CI: 0.06-0.35), according to AECG criteria. According to EU-1 criteria, these prevalence rates were found to be 0.35% (95% CI: 0.10-0.45) and 0.28% (95% CI: 0.13-0.51) respectively. CONCLUSION: The pSS prevalence rates found in the Turkish population in this study were lower than the estimated prevalence rate in a general population.
20060386 Performance characteristics of three random access cyclic citrullinated peptide antibody a 2010 Mar BACKGROUND: Cyclic citrullinated peptide antibodies (CCP Ab) are useful biomarkers for the early detection and diagnosis of rheumatoid arthritis (RA). METHODS: We evaluated the performance of 3 random access 2nd generation CCP Ab assays, the Abbott AxSYM and Architect analyzers and the Roche Modular Analytics E170 analyzer, for limit of detection (LOD), imprecision, results for samples from healthy subjects, analytic concordance, and interferences. Method comparison testing was performed using the AxSYM analyzer as the comparison method and a 3rd generation INOVA Quanta Lite ELISA assay was included. RESULTS: LOD determinations met the manufacturers' claims. Total CVs ranged from 1.6% to 8.2%. Results from healthy subjects were generally much lower than the manufacturers' decision cutoffs. Comparison to the AxSYM assay resulted in overall concordance ranging from 82.1% to 98.3%. These assays were resistant to interference from hemolysis, icterus, lipemia and rheumatoid factor. CONCLUSION: All 3 random access CCP Ab assays performed according to the manufacturers' claims and have the potential to improve workflow in clinical laboratories.
19139949 Association of complementary or alternative medicine use with quality of life, functional 2009 May Quality of life, functional status, or cumulated damage were compared between users and non-users of complementary and alternative medicine (CAM) in 445 rheumatic patients (rheumatoid arthritis [RA]: 64; systemic lupus erythematosus [SLE]: 192; fibromyalgia [FM]: 34; and knee osteoarthritis [KOA]: 155). CAM use was reported by 249 subjects (55.9%; 95%CI; 51.4-60.6). After a general linear model was applied, CAM use was associated with lower scores in the physical function (p = 0.02) and bodily pain (p = 0.03) domains of the SF-36 survey. In FM, RA and KOA, functional status was not different between users and non-users. CAM use was associated with higher cumulated damage (p = 0.04) in SLE. In patients with chronic rheumatic diseases, CAM use was not associated with better quality of life. Additionally, in SLE patients, CAM use was associated with higher cumulated damage. More research on CAM use in chronic rheumatic diseases is needed to better delineate its risk/benefit profile.
18676139 "Macromolecules to PDMS transfer" as a general route for PDMS biochips. 2009 Jan 1 "Macromolecules to PDMS transfer" technique relying on the direct entrapment of macromolecules spots during PDMS polymerisation is proposed as an alternative for the easy and simple PDMS surface modification. In the present work, the development of three different applications based on this procedure is presented as proof of the method potentialities. First, C-reactive protein (CRP) sandwich immunoassay using immobilised monoclonal anti-CRP antibodies was developed for sepsis diagnosis. The preserved integrity of the immobilised monoclonal immunoglobulin permitted the sensitive detection of free CRP in human sera (LOD=12.5 microg/L, detection ranging over two decades). Then, rheumatoid arthritis diagnosis through the rheumatoid factor (RF) detection based on rabbit immunoglobulins immobilisation allowed the detection of specific antibodies in human sera samples down to low RF levels (detection range 5.3-485 IU/mL). Finally, the "Macromolecules to PDMS transfer" procedure was used to easily and rapidly produce fibronectin-based cell culture arrays. The successful attachment of HeLa and BALB/3T3 cells was demonstrated with optical microscopy and specific staining of actin and vinculin.
19336591 Pivotal clinical dilemmas in collagen vascular diseases associated with interstitial lung 2009 Apr The connective tissue disorders (CTDs), also called collagen vascular diseases (CVDs), represent a heterogeneous group of immunologically mediated inflammatory disorders with a large variety of affected organs. Individuals with a CTD (rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, Sjögren's syndrome, polymyositis/dermatomyositis and mixed connective tissue disease) are susceptible to respiratory involvement. When the lungs are affected, an increasing mortality and morbidity in CVDs occurs. Interstitial lung disease (ILD) is established as a clinical corollary across the spectrum of CTDs, with an overall incidence estimated at 15%. Therefore, pivotal clinical dilemmas remain in the evaluation and management of ILD involvement in CVDs. Critical questions are the presence of fibrosis and whether the disease is clinically significant. Moreover, the clinician has to decide if treatment is warranted and which is the best therapeutic approach. The use of additional tests, such as pulmonary function tests, high-resolution computed tomography scan, bronchoalveolar lavage fluid and surgical lung biopsy, deserves better discussion. The present review focuses on establishing the diagnosis of ILD in CTD, and on evaluating disease activity and prognosis. This will provide the basis for therapeutic decisions that will be discussed, including an overview of recent advances.
21053035 Rituximab in cryoglobulinaemic vasculitis, evidence for its effectivity: a case report and 2011 Feb Cryoglobulinaemia associated with systemic vasculitis mediated by immune complexes is a rare combination. These immune complexes are composed of immunoglobulins and precipitate when exposed to cold temperature. Cryoglobulinaemic vasculitis, treated or untreated, may lead to substantial morbidity and even mortality. Novel targeted therapies may well provide new therapeutic options following or perhaps even prior to the classical cytotoxic therapies. Systemic B cell depletion with rituximab, a chimeric monoclonal antibody against CD20 antigen, is commonly applied in patients with non-Hodgkin's lymphoma or in refractory rheumatoid factor-positive rheumatoid arthritis. Since B cell clones are the source of cryoglobulins, therapeutic effectiveness of rituximab in cryoglobulinaemic vasculitis may be expected. We describe a 72-year-old woman with mixed cryoglobulinaemia type 2, who has successfully been treated with rituximab infusions after failing on prednisone and azathioprine. We reviewed the literature and found 142 cases of cryoglobulinaemic vasculitis, 138 mixed (type 2 or 3) and four, type 1. Rituximab was applied mostly after failure on other treatments. Significant reduction in levels of rheumatoid factor, cryoglobulins and IgM were reported after rituximab therapy. Of the total 142, cases 119 could be evaluated for the response on rituximab therapy, the other 23 cases only regarding side effects. Of the 119 evaluated patients, 71 (60%) had complete response; 28 (23%), partial response and 20 patients (17%), no response. Data were not blinded or placebo-controlled. Side effects were seen in 27 of the 142 patients. Occurrence of the side effects was associated with high baseline levels of cryoglobulins, with a high dose of rituximab infusion of 1,000 mg and with a high level of complement activation. Death was reported four times and was related with the disease.
19122291 Preventive effect of co-administration of water containing magnesium ion on indomethacin i 2009 Jan It is well known that nonsteroidal anti-inflammatory drugs (NSAIDs) have significant side effects, such as gastroenteropathy, and that rheumatoid arthritis patients taking NSAIDs are more susceptible to NSAIDs-induced gastric lesions as compared with patients with other diseases. We demonstrate the preventive effect of the co-administration of bittern water (BW, nigari-sui in Japanese), which enables the effective intake of Mg(2+), on the ulcerogenic response to indomethacin in adjuvant-induced arthritis (AA) rats. Four kinds of BW with different Mg(2+) contents; ranging from 10-200 mg/l Mg(2+) (BW-10, 25, 50, 200) were used in this study. Arthritis was induced by the injection of 50 microl of a suspension of 10 mg/ml heat-killed butyricum (Mycobacterium butyricum) in Bayol F oil into the plantar region of the right hind foot and tail of rats. Oral administration of indomethacin (40 mg/kg) caused hemorrhagic lesions in the gastric mucosa of AA rats at 14 d after adjuvant injection, and the lesion score of AA rats administered indomethacin was significantly higher than that of normal rats administered indomethacin. The expression of the mRNA for inducible nitric oxide synthase (iNOS) mRNA expression and the production of nitric oxide (NO) in the gastric mucosa of AA rats were also increased by the administration of indomethacin. The co-administration of BWs decreased the ulcerogenic response to indomethacin in AA rats. In addition, the administration of BW attenuated the increase in iNOS mRNA expression and NO production in AA rats receiving indomethacin. The oral administration of Mg(2+) to AA rats had a potent preventive effect on the ulcerogenic response to indomethacin in AA rats, probably due to an inhibition in the rise in iNOS and NO levels in the gastric mucosa.
20519361 Systemic IGF-I administration attenuates the inhibitory effect of chronic arthritis on gas 2010 Aug Adjuvant arthritis is an animal model of rheumatoid arthritis that decreases liver and circulating IGF-I as well as skeletal muscle mass. The aim of this work was to elucidate whether IGF-I administration was able to prevent the effect of arthritis on body weight and on two skeletal muscles, gastrocnemius and soleus. On day 4 after adjuvant injection, control and arthritic rats were treated with IGF-I (100 microg/kg s.c.) two times a day, until day 15 when all rats were killed. Arthritis decreased body weight gain and gastrocnemius weight. In arthritic rats, IGF-I treatment increased body weight gain and gastrocnemius weight, without modifying food intake or the external signs of arthritis. Arthritis increased atrogin-1 and muscle ring finger 1 (MuRF1) gene expression in the gastrocnemius and to a lesser extent in the soleus muscle. IGF-I attenuated the arthritis-induced increase in atrogin-1 and MuRF1 expression in the gastrocnemius, whereas it did not modify the expression of these genes in the soleus muscle. Arthritis also increased IGF-binding protein (IGBP)-3 and IGFBP-5 gene expression in gastrocnemius and soleus, whereas IGF-I administration decreased IGFBP-3, but not IGFBP-5, gene expression in both muscles. In both groups of arthritic rats and in control rats treated with IGF-I, proliferating cell nuclear antigen and myogenic differentiation proteins were increased in the gastrocnemius. These data suggest that the inhibitory effect of chronic arthritis on skeletal muscle is higher in fast glycolytic than in slow oxidative muscle and that IGF-I administration attenuates this effect and decreases atrogin-1 and IGFBP-3 gene expression.
20360190 Using magnetic resonance angiography to measure abnormal synovial blood vessels in early i 2010 Jun OBJECTIVE: To ascertain whether magnetic resonance angiography (MRA) can reliably detect synovial neovascularization in subjects with early inflammatory arthritis. METHODS: Subjects with 6 weeks to 6 months of clinical evidence of inflammatory hand arthritis had a radiograph, power Doppler ultrasound (PDU) scan, magnetic resonance imaging (MRI), and contrast enhanced MRA performed on the more symptomatic hand. Ultrasound examination of the wrist and 2nd-5th metacarpophalangeal (MCP) joints was scored for erosions, synovial thickening, and synovial blood flow. MRI were assessed using the OMERACT Rheumatoid Arthritis MRI Score (RAMRIS). MRA was used to assess the number of abnormal vessels in the 2nd-5th MCP and in the wrist. RESULTS: Of 30 subjects, 66.7% showed abnormal vasculature on MRA in the MCP and/or wrist; mean number of abnormal vessels was 5.24 (range 0-22). Number of abnormal vessels on MRA was strongly correlated with degree of blood flow seen in the corresponding area on PDU (r = 0.79, p
19644855 Hypoxia and glucocorticoid signaling converge to regulate macrophage migration inhibitory 2009 Aug OBJECTIVE: Macrophage migration inhibitory factor (MIF) is a proinflammatory mediator involved in the pathogenesis of rheumatoid arthritis. This study was undertaken to identify the MIF promoter elements responsible for regulating gene expression. METHODS: Luciferase reporter gene assays were used to identify the MIF promoter sequence responsible for basal activity. Bioinformatic analysis was used to predict transcription factor binding sites, and electrophoretic mobility shift assay (EMSA) was used to demonstrate transcription factor binding. Chromatin immunoprecipitation (ChIP) was used to demonstrate transcription factor loading on the MIF promoter. RESULTS: We identified the minimal promoter sequence required for basal MIF promoter activity that was also capable of conferring glucocorticoid-dependent inhibition in a T lymphocyte model cell line. Deletion studies and EMSA revealed 2 elements in the MIF promoter that were responsible for basal promoter activity. The 5' element binds CREB/activating transcription factor 1, and the 3' element is a functional hypoxia-responsive element binding hypoxia-inducible factor 1alpha. Further studies demonstrated that the cis elements are both required for glucocorticoid-dependent inhibition. ChIP demonstrated glucocorticoid-dependent recruitment of glucocorticoid receptor alpha to the MIF promoter in lymphocytes within 1 hour of treatment and a concomitant decrease in acetylated histone H3. CONCLUSION: Our findings indicate that hypoxia and glucocorticoid signaling converge on a single element regulating MIF; this regulatory unit is a potential interacting node for microenvironment sensing of oxygen tension and glucocorticoid action in foci of inflammation.
20848388 Formulation and evaluation of chitosan microspheres of aceclofenac for colon-targeted drug 2010 Oct The objective of this investigation was to develop novel colon specific drug delivery. Aceclofenac, a NSAID, was successfully encapsulated into chitosan microspheres. Various formulations were prepared by varying the ratio of chitosan, span-85 and stirring speed and the amount of glutaraldehyde. The SEM study showed that microspheres have smooth surfaces. Microspheres were characterised by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) to confirm the absence of chemical interactions between drug and polymer and to know the formation of microspheres structure. The microspheres were evaluated for particle size, encapsulation efficiency, drug loading capacity, mucoadhesion studies, stability studies, in vitro and in vivo drug release studies. Particle sizes, as measured by the laser light scattering technique, were of an average size in the range 41-80 µm. The swelling index was in the range 0.37-0.82 and the entrapment efficiency range was 51-75% for all the formulations. The optimised batch ACM(13) released 83.6% at 8 h and 104% at 24 h in SCF containing rat caecal content. Eudragit coated chitosan microspheres prevented the release of the aceclofenac in the physiological environment of the stomach and small intestine and released 95.9±0.34% in the colon. With regard to release kinetics, the data were best fitted with the Higuchi model and showed zero order release with non-Fickian diffusion mechanism. The in vivo findings suggest that aceclofenac microspheres exhibit a prolonged effect of aceclofenac in rats and produce a significant anti-inflammatory effect. The findings of the present study conclusively state that chitosan microspheres are promising for colon targeting of aceclofenac to synchronise with chronobiological symptoms of rheumatoid arthritis.
19775984 The application of machine learning algorithms to the analysis of electromyographic patter 2010 Apr The main aim of our study was to investigate the possibility of applying machine learning techniques to the analysis of electromyographic patterns (EMG) collected from arthritic patients during gait. The EMG recordings were collected from the lower limbs of patients with arthritis and compared with those of healthy subjects (CO) with no musculoskeletal disorder. The study involved subjects suffering from two forms of arthritis, viz, rheumatoid arthritis (RA) and hip osteoarthritis (OA). The analysis of the data was plagued by two problems which frequently render the analysis of this type of data extremely difficult. One was the small number of human subjects that could be included in the investigation based on the terms specified in the inclusion and exclusion criteria for the study. The other was the high intra- and inter-subject variability present in EMG data. We identified some of the muscles differently employed by the arthritic patients by using machine learning techniques to classify the two groups and then identified the muscles that were critical for the classification. For the classification we employed least-squares kernel (LSK) algorithms, neural network algorithms like the Kohonen self organizing map, learning vector quantification and the multilayer perceptron. Finally we also tested the more classical technique of linear discriminant analysis (LDA). The performance of the different algorithms was compared. The LSK algorithm showed the highest capacity for classification. Our study demonstrates that the newly developed LSK algorithm is adept for the treatment of biological data. The muscles that were most important for distinguishing the RA from the CO subjects were the soleus and biceps femoris. For separating the OA and CO subjects however, it was the gluteus medialis muscle. Our study demonstrates how classification with EMG data can be used in the clinical setting. While such procedures are unnecessary for the diagnosis of the type of arthritis present, an understanding of the muscles which are responsible for the classification can help to better identify targets for rehabilitative measures.