Case report: Atypical presentation of rheumatoid arthritis that initially presented as osteoarthritis

Case report: Atypical presentation of rheumatoid arthritis that initially presented as osteoarthritis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Case report: Atypical presentation of rheumatoid arthritis that initially presented as osteoarthritis Miqdad Dafaallah, Ana Leal Bramasco, Ackeime Campbell, Konstantin Brodetskiy This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6534891/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Rheumatoid arthritis (RA) is well-known for its inflammatory characteristics of pain, stiffness and swelling of the joint. Although it may result in any joint involvement, it usually affects the small joints in the hand, foot, wrist and shoulder. This case highlights an atypical presentation of RA which initially manifested as primary osteoarthritis (OA) with the absence of classic synovitis and emphasizes the importance in considering RA in the differential diagnoses especially, when symptoms involve joints that are atypical for OA. Case description: In this case report, a man came for an outpatient assessment with pain and stiffness of bilateral knees, for which he was being treated for chronic OA. Two total knee replacements were performed resulting in satisfactory relief of symptoms. Surprisingly, he developed new symptoms of OA involving atypical joints for OA in the form of glenohumeral joint OA and OA at the distal radioulnar joint. Although the examination findings of synovitis were initially absent, the serological diagnosis of RA was later made. Conclusion: This case serves as a reminder that RA can mimic primary OA, and serological testing should be considered in cases with unusual joint involvement even in the absence of inflammatory signs. Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Rheumatoid arthritis (RA) is an inflammatory disease that presents with pain, stiffness, and joint swelling ( 1 ). RA commonly involves multiple joints, with the hand being the most common (28%), followed by the foot (13%), wrist (8%), and shoulder (4%)( 2 ). Patients with long-standing RA may develop secondary osteoarthritis (OA)( 3 ). Primary OA is commonly presented with reduced range of motion and effusion, and it affects joints of the hand (the distal interphalangeal (DIP), proximal interphalangeal (PIP), and trapeziometacarpal joints), knee, spine, and hips. However, in secondary OA, other atypical joints might be affected, such as the glenohumeral joint ( 4 ), and inflammatory manifestations, such as warmth and erythema, might be present on physical examination ( 5 ). Here we present an atypical case of a man who presented with OA without synovitis at sites which are typical for RA. Methods A comprehensive review of the case was conducted to write the case report that includes patient’s medical history, medical records, imaging studies, and laboratory findings. The patient’s initial presentation, progression of symptoms, workup, and management course were documented systematically. The diagnosis of OA was made based on clinical presentation, imaging findings and lack of inflammatory symptoms. As the patient’s symptoms evolved, serological testing for inflammatory arthritis was conducted leading to the diagnosis of RA. Case presentation A male in his 60s with a past medical history of diabetes mellitus and hypertension presented to the orthopedic surgery clinic for chronic progressive constant bilateral knee pain. Initially, the pain was on the right knee and progressed to the left knee over a period of 10 years. Pain was not improved by ibuprofen or physical therapy. Due to the pain, the patient used a cane for several months and then progressed to needing a rolling walker. He denied any other joint involvement, morning stiffness or constitutional symptoms. On examination, the patient was noted to be ambulating with a rolling walker seated being pushed by his daughter. On bilateral knee examinations, Genu Varus deformities are seen in both knees, but no bony deformity, warmth, or effusion. The range of motion was decreased in both knees in flexion and extension with the right knee being affected more than the left knee. The patient continued to receive Physical Therapy, non-steroidal anti-inflammatory drugs (NSAIDs) and cortisone injections with no significant improvement. Two months later he also developed bilateral shoulder pain. Examination revealed restriction of movement with overhead abduction in both shoulders and tenderness over the distal radioulnar joint with both active and passive movements. A diagnosis of severe Osteoarthritis (OA) of the knees was made with early OA of the left glenohumeral joint. Two months later he underwent total right knee replacement. Three months later, the patient returned for worsening pain in the left knee that significantly affected his walking. The range of movement of the left knee showed impaired extension and flexion due to severe pain. Radiography of the left knee showed severe reduction in medial joint spaces with osteophytes and subchondral sclerosis (Figure 1), suggestive of severe left knee OA. The patient eventually underwent total replacement of the left knee and a pathology specimen was sent which is suggestive of OA (Figure 2). The patient underwent physical therapy and had recovered well. The clinical course was further complicated four months later, when the patient presented with right wrist pain associated with swelling, which was aggravated by extension of the wrist and daily activities such as eating and shaving. Radiography revealed evidence of osteoarthrosis of the right wrist at the radioulnar joint (Figure 3). Thereafter, the patient was diagnosed with severe right distal radial ulnar arthritis and underwent right wrist arthroplasty (Figure 4) The patient developed hip pain associated with stiffness for 10 minutes in the morning, and was referred to rheumatology clinic for further evaluation. On examination, the patient was noted to have hallux valgus bilaterally, groin tenderness, and left hip restriction of movement due to pain on internal rotation. He had no obvious signs of active inflammatory arthritis such as erythema, swelling, or warmth. In light of this patient having had widespread OA, symmetric joint involvement in atypical joints, Rheumatoid Factor (RF) and Cyclic Citrullinated Peptide antibodies (CCP), Erythrocyte Sedimentation Rate (ESR), and C-Reactive Protein (CRP) were sent. Results showed a positive RF of 67 IU/mL (reference range 0-13 IU/mL), CCP antibodies of >250 units (reference range <=19 units), ESR of 45 and CRP of 7. The patient was diagnosed with RA, on the basis of serological and radiological findings significant for secondary OA. Although there was no synovitis present on exam, the patient was started on methotrexate 15 mg to prevent further joint destruction. Three months later the patient presented with pain and swelling in multiple joints including metacarpophalangeal, proximal interphalangeal, and knee joints. ESR and CRP were 120 and 113 respectively. A steroid taper was added, and methotrexate was increased to 25 mg. Swelling subsequently had resolved in all joints with exception of the ankles. Discussion OA is a chronic degenerative joint disease which leads to the destruction of articular cartilage and adjacent bone ( 6 ). Primary and secondary OA can affect any joint, most commonly including knees, hips, cervical and lumbar spine, small joints of the hands (including distal and proximal interphalangeal joints), first carpometacarpal, tarsometatarsal, and lateral metatarsophalangeal joints of the feet ( 7 , 8 ). OA of the distal radioulnar joint (DRUJ) is usually related to trauma (especially radius fractures) ( 6 ), metabolic and inflammatory arthropathies ( 9 ). In this case, we describe a patient who initially presented with symptoms and radiographic evidence of chronically progressive OA. Initial presentation with involvement of knees was typical for primary OA. However subsequent involvement of shoulders, and then wrists raised suspicion for inflammatory arthritis. In particular, DRUJ involvement which in OA has been described in the setting of trauma ( 6 ), however our patient has no history of previous fracture, making the diagnosis of DRUJ OA concerning for other causes such as inflammatory arthritis The patient presented with OA that started to involve atypical sites, and had no signs of synovitis on exam. However, his disease activity increased, and the patient started to develop flares and eventually was diagnosed with RA. This is atypical for RA; in typical disease patients usually develop hands’ joints pain, swelling, and morning stiffness, and later they will develop complications such as deformities and secondary OA. Initially, this patient did not meet the classification criteria as per ACR/EULAR 2010 RA criteria ( 10 ), with a total score of 2 and absence of synovitis features in any joint; however, no RF or ACCP was checked at that time. Later, the patient's total score was 6 and he developed synovitis. In our literature review we came across a case that presented with OA for 5 years before developing characteristic symptoms and signs of RA ( 11 ). We would close on that; this case highlights the need to consider RA if a patient develops OA in a distribution typical of RA. Declarations Ethics approval and consent to participate: Ethical approval was not required Consent for publication: written consent was taken from the patient for writing and publishing the case. Availability of data and materials: not applicable Competing Interests: no competing interests Funding: no funding Authors' contributions: All authors contributed to writing and proofreading the case. References Lee DM, Weinblatt ME. Rheumatoid arthritis. Lancet. 2001 Sep 15;358(9285):903-11. doi: 10.1016/S0140-6736(01)06075-5. PMID: 11567728. Fleming A, Crown JM, Corbett M. Early rheumatoid disease. I. Onset. Ann Rheum Dis. 1976 Aug;35(4):357-60. doi: 10.1136/ard.35.4.357. PMID: 970994; PMCID: PMC1007396. Hinton R, Moody RL, Davis AW, Thomas SF. Osteoarthritis: diagnosis and therapeutic considerations. Am Fam Physician. 2002 Mar 1;65(5):841-8. PMID: 11898956 Davis A. Hartnett, John D. Milner, Steven F. DeFroda, Osteoarthritis in the Upper Extremity, The American Journal of Medicine, Volume 136, Issue 5, 2023, Pages 415-421, ISSN 0002-9343, https://doi.org/10.1016/j.amjmed.2023.01.025. Rafaelani L. Taruc-Uy, Scott A. Lynch, Diagnosis and Treatment of Osteoarthritis, Primary Care: Clinics in Office Practice, Volume 40, Issue 4, 2013, Pages 821-836, ISSN 0095-4543, ISBN 9780323261227, https://doi.org/10.1016/j.pop.2013.08.003. Grunz JP, Gietzen CH, Christopoulos G, van Schoonhoven J, Goehtz F, Schmitt R, Hesse N. Osteoarthritis of the Wrist: Pathology, Radiology, and Treatment. Semin Musculoskelet Radiol. 2021 Apr;25(2):294-303. doi: 10.1055/s-0041-1730948. Epub 2021 Aug 9. PMID: 34374064. van Saase JL, van Romunde LK, Cats A, Vandenbroucke JP, Valkenburg HA. Epidemiology of osteoarthritis: Zoetermeer survey. Comparison of radiological osteoarthritis in a Dutch population with that in 10 other populations. Ann Rheum Dis. 1989 Apr;48(4):271-80. doi: 10.1136/ard.48.4.271. PMID: 2712610; PMCID: PMC1003741. Abramoff B, Caldera FE. Osteoarthritis: pathology, diagnosis, and treatment options. Med Clin North Am. 2020 Mar;104(2):293-311 Laulan J, Marteau E, Bacle G. Wrist osteoarthritis. Orthop Traumatol Surg Res. 2015 Feb;101(1 Suppl):S1-9. doi: 10.1016/j.otsr.2014.06.025. Epub 2015 Jan 14. PMID: 25596986. Kay J, Upchurch KS. ACR/EULAR 2010 rheumatoid arthritis classification criteria. Rheumatology (Oxford). 2012 Dec;51 Suppl 6:vi5-9. doi: 10.1093/rheumatology/kes279. PMID: 23221588. Devaraj NK. The Atypical Presentation of Rheumatoid Arthritis in an Elderly Woman: A Case Report. Ethiop J Health Sci. 2019 Jan;29(1):957-958. doi: 10.4314/ejhs.v29i1.18. PMID: 30700964; PMCID: PMC6341435. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6534891","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":462628660,"identity":"16893c62-c705-49bc-804a-58bda4d457f9","order_by":0,"name":"Miqdad Dafaallah","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/UlEQVRIiWNgGAWjYDACZgYGCQY2CWZ+ZuaDDz5UgESYG4jRYsEu2c6WbDjjDEiEkYAWBrCWCn6D8zxm0pxtID4BLbrtzBtv/CiTkGY4DNTCOK82mr8dqOVHxTacWswOsxVb9pyTMGZsZiu2Ltx2PHfGYcYGxp4zt/Fo4TGT4G2TSGZmZt54e+a2Y7kNQC3MjG34tUj+bZOob2NmMJDmnXMsdz4xWqSBtjDzMLMYSfM21ORuIKwF6AWZcxLMEsygQD52IHcjUMtBvH45f3jjzTdldcz25w8Do7KmLnceiPGjArcWIDBA5hwGkwfwqUfXUkdA8SgYBaNgFIxEAADVRlesi+NNMQAAAABJRU5ErkJggg==","orcid":"","institution":"Woodhull Medical and Mental Health Center","correspondingAuthor":true,"prefix":"","firstName":"Miqdad","middleName":"","lastName":"Dafaallah","suffix":""},{"id":462628661,"identity":"d362b16e-d041-44a1-8a7c-b8c21ef68127","order_by":1,"name":"Ana Leal Bramasco","email":"","orcid":"","institution":"Woodhull Medical and Mental Health Center","correspondingAuthor":false,"prefix":"","firstName":"Ana","middleName":"Leal","lastName":"Bramasco","suffix":""},{"id":462628662,"identity":"4269c8e1-a98f-4501-8607-9415f90ab2b6","order_by":2,"name":"Ackeime Campbell","email":"","orcid":"","institution":"Woodhull Medical and Mental Health Center","correspondingAuthor":false,"prefix":"","firstName":"Ackeime","middleName":"","lastName":"Campbell","suffix":""},{"id":462628663,"identity":"2c8fd1c9-3501-4aaf-8756-151555c4d96d","order_by":3,"name":"Konstantin Brodetskiy","email":"","orcid":"","institution":"Woodhull Medical and Mental Health Center","correspondingAuthor":false,"prefix":"","firstName":"Konstantin","middleName":"","lastName":"Brodetskiy","suffix":""}],"badges":[],"createdAt":"2025-04-26 12:08:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6534891/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6534891/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":83623661,"identity":"6a663604-6205-439b-acd7-595fe34dce01","added_by":"auto","created_at":"2025-05-29 15:59:20","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":152254,"visible":true,"origin":"","legend":"\u003cp\u003eleft knee there is no evidence of acute fracture or dislocation. Significant degenerative changes at the knee which included severe joint space loss more severe in the medial compartment. Prominent spurring is seen at the knee and at the patellofemoral region. There were also soft tissue calcifications which appeared to be associated with the joint.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6534891/v1/83990b7655e984731be19e5d.png"},{"id":83624066,"identity":"21e13a35-e1cf-4511-8752-5358b8998c53","added_by":"auto","created_at":"2025-05-29 16:07:20","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":550760,"visible":true,"origin":"","legend":"\u003cp\u003eSpecimen from the left knee showed signs suggestive of OA\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6534891/v1/413119a001a681fb7bcef145.png"},{"id":83623664,"identity":"89a95a84-3c6d-49d8-a85b-dd7f071dbeb5","added_by":"auto","created_at":"2025-05-29 15:59:20","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":206210,"visible":true,"origin":"","legend":"\u003cp\u003e(a) and (b): There were degenerative changes at the scaphotrapeziotrapezoidal and distal radioulnar joints.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6534891/v1/12f8f4d07d90a9cba7aba49e.png"},{"id":83623662,"identity":"a8f3ea3a-7753-4c4d-8fd6-d04983dcf7a5","added_by":"auto","created_at":"2025-05-29 15:59:20","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":117575,"visible":true,"origin":"","legend":"\u003cp\u003eStatus post arthrodesis of the distal radioulnar joint with two cancellous screws is demonstrated. This film is post resection of an approximately 14 mm segment of the distal diaphysis of the ulna.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6534891/v1/7d244dce3f3f18003d96d4b7.png"},{"id":84789999,"identity":"6c2efe55-a7bd-4551-9450-ce001ee61e12","added_by":"auto","created_at":"2025-06-17 11:09:08","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1442474,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6534891/v1/53b4bc8c-057c-4257-8191-41a2d769e65e.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Case report: Atypical presentation of rheumatoid arthritis that initially presented as osteoarthritis","fulltext":[{"header":"Introduction","content":"\u003cp\u003eRheumatoid arthritis (RA) is an inflammatory disease that presents with pain, stiffness, and joint swelling (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). RA commonly involves multiple joints, with the hand being the most common (28%), followed by the foot (13%), wrist (8%), and shoulder (4%)(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Patients with long-standing RA may develop secondary osteoarthritis (OA)(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Primary OA is commonly presented with reduced range of motion and effusion, and it affects joints of the hand (the distal interphalangeal (DIP), proximal interphalangeal (PIP), and trapeziometacarpal joints), knee, spine, and hips. However, in secondary OA, other atypical joints might be affected, such as the glenohumeral joint (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e), and inflammatory manifestations, such as warmth and erythema, might be present on physical examination (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eHere we present an atypical case of a man who presented with OA without synovitis at sites which are typical for RA.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eA comprehensive review of the case was conducted to write the case report that includes patient’s medical history, medical records, imaging studies, and laboratory findings. The patient’s initial presentation, progression of symptoms, workup, and management course were documented systematically.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe diagnosis of OA was made based on clinical presentation, imaging findings and lack of inflammatory symptoms. As the patient’s symptoms evolved, serological testing for inflammatory arthritis was conducted leading to the diagnosis of RA.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eA male in his 60s with a past medical history of diabetes mellitus and hypertension presented to the orthopedic surgery clinic for chronic progressive constant bilateral knee pain. Initially, the pain was on the right knee and progressed to the left knee over a period of 10 years. Pain was not improved by ibuprofen or physical therapy. Due to the pain, the patient used a cane for several months and then progressed to needing a rolling walker. He denied any other joint involvement, morning stiffness or constitutional symptoms.\u003c/p\u003e\n\u003cp\u003eOn examination, the patient was noted to be ambulating with a rolling walker seated being pushed by his daughter. On bilateral knee examinations, Genu Varus deformities are seen in both knees, but no bony deformity, warmth, or effusion. The range of motion was decreased in both knees in flexion and extension with the right knee being affected more than the left knee.\u003c/p\u003e\n\u003cp\u003eThe patient continued to receive Physical Therapy, non-steroidal anti-inflammatory drugs (NSAIDs) and cortisone injections with no significant improvement. Two months later he also developed bilateral shoulder pain. Examination revealed restriction of movement with overhead abduction in both shoulders and tenderness over the distal radioulnar joint with both active and passive movements.\u003c/p\u003e\n\u003cp\u003eA diagnosis of severe Osteoarthritis (OA) of the knees was made with early OA of the left glenohumeral joint. Two months later he underwent total right knee replacement.\u003c/p\u003e\n\u003cp\u003eThree months later, the patient returned for worsening pain in the left knee that significantly affected his walking. The range of movement of the left knee showed impaired extension and flexion due to severe pain. Radiography of the left knee showed severe reduction in medial joint spaces with osteophytes and subchondral sclerosis (Figure 1), suggestive of severe left knee OA. The patient eventually underwent total replacement of the left knee and a pathology specimen was sent which is suggestive of OA (Figure 2).\u003c/p\u003e\n\u003cp\u003eThe patient underwent physical therapy and had recovered well. The clinical course was further complicated four months later, when the patient presented with right wrist pain associated with swelling, which was aggravated by extension of the wrist and daily activities such as eating and shaving. Radiography revealed evidence of osteoarthrosis of the right wrist at the radioulnar joint (Figure 3). Thereafter, the patient was diagnosed with severe right distal radial ulnar arthritis and underwent right wrist arthroplasty (Figure 4)\u003cbr\u003e\u003cbr\u003e The patient developed hip pain associated with stiffness for 10 minutes in the morning, and was referred to rheumatology clinic for further evaluation. On examination, the patient was noted to have hallux valgus bilaterally, groin tenderness, and left hip restriction of movement due to pain on internal rotation. He had no obvious signs of active inflammatory arthritis such as erythema, swelling, or warmth. In light of this patient having had widespread OA, symmetric joint involvement in atypical joints, Rheumatoid Factor (RF) and Cyclic Citrullinated Peptide antibodies (CCP), Erythrocyte Sedimentation Rate (ESR), and C-Reactive Protein (CRP) were sent. Results showed a positive RF of 67 IU/mL (reference range 0-13 IU/mL), CCP antibodies of \u0026gt;250 units (reference range \u0026lt;=19 units), ESR of 45 and CRP of 7.\u003cbr\u003e The patient was diagnosed with RA, on the basis of serological and radiological findings significant for secondary OA. Although there was no synovitis present on exam, the patient was started on methotrexate 15 mg to prevent further joint destruction.\u003cbr\u003e \u003cbr\u003e Three months later the patient presented with pain and swelling in multiple joints including metacarpophalangeal, proximal interphalangeal, and knee joints. ESR and CRP were 120 and 113 respectively. A steroid taper was added, and methotrexate was increased to 25 mg. Swelling subsequently had resolved in all joints with exception of the ankles.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eOA is a chronic degenerative joint disease which leads to the destruction of articular cartilage and adjacent bone (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Primary and secondary OA can affect any joint, most commonly including knees, hips, cervical and lumbar spine, small joints of the hands (including distal and proximal interphalangeal joints), first carpometacarpal, tarsometatarsal, and lateral metatarsophalangeal joints of the feet (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). OA of the distal radioulnar joint (DRUJ) is usually related to trauma (especially radius fractures) (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e), metabolic and inflammatory arthropathies (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). In this case, we describe a patient who initially presented with symptoms and radiographic evidence of chronically progressive OA. Initial presentation with involvement of knees was typical for primary OA. However subsequent involvement of shoulders, and then wrists raised suspicion for inflammatory arthritis. In particular, DRUJ involvement which in OA has been described in the setting of trauma (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e), however our patient has no history of previous fracture, making the diagnosis of DRUJ OA concerning for other causes such as inflammatory arthritis\u003c/p\u003e \u003cp\u003eThe patient presented with OA that started to involve atypical sites, and had no signs of synovitis on exam. However, his disease activity increased, and the patient started to develop flares and eventually was diagnosed with RA. This is atypical for RA; in typical disease patients usually develop hands\u0026rsquo; joints pain, swelling, and morning stiffness, and later they will develop complications such as deformities and secondary OA.\u003c/p\u003e \u003cp\u003eInitially, this patient did not meet the classification criteria as per ACR/EULAR 2010 RA criteria (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e), with a total score of 2 and absence of synovitis features in any joint; however, no RF or ACCP was checked at that time. Later, the patient's total score was 6 and he developed synovitis.\u003c/p\u003e \u003cp\u003eIn our literature review we came across a case that presented with OA for 5 years before developing characteristic symptoms and signs of RA (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eWe would close on that; this case highlights the need to consider RA if a patient develops OA in a distribution typical of RA.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate: Ethical approval was not required\u0026nbsp;\u003cbr\u003e\u0026nbsp;Consent for publication: written consent was taken from the patient for writing and publishing the case.\u003cbr\u003e\u0026nbsp;Availability of data and materials: not applicable\u0026nbsp;\u003cbr\u003e\u0026nbsp;Competing Interests: no competing interests\u0026nbsp;\u003cbr\u003e\u0026nbsp;Funding: no funding \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003cbr\u003e\u0026nbsp;Authors' contributions: All authors contributed to writing and proofreading the case.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eLee DM, Weinblatt ME. Rheumatoid arthritis. Lancet. 2001 Sep 15;358(9285):903-11. doi: 10.1016/S0140-6736(01)06075-5. PMID: 11567728.\u003c/li\u003e\n \u003cli\u003eFleming A, Crown JM, Corbett M. Early rheumatoid disease. I. Onset. Ann Rheum Dis. 1976 Aug;35(4):357-60. doi: 10.1136/ard.35.4.357. PMID: 970994; PMCID: PMC1007396.\u003c/li\u003e\n \u003cli\u003eHinton R, Moody RL, Davis AW, Thomas SF. Osteoarthritis: diagnosis and therapeutic considerations. Am Fam Physician. 2002 Mar 1;65(5):841-8. PMID: 11898956\u003c/li\u003e\n \u003cli\u003eDavis A. Hartnett, John D. Milner, Steven F. DeFroda, Osteoarthritis in the Upper Extremity, The American Journal of Medicine, Volume 136, Issue 5, 2023, Pages 415-421, ISSN 0002-9343, https://doi.org/10.1016/j.amjmed.2023.01.025.\u003c/li\u003e\n \u003cli\u003eRafaelani L. Taruc-Uy, Scott A. Lynch, Diagnosis and Treatment of Osteoarthritis, Primary Care: Clinics in Office Practice, Volume 40, Issue 4, 2013, Pages 821-836, ISSN 0095-4543, ISBN 9780323261227, https://doi.org/10.1016/j.pop.2013.08.003.\u003c/li\u003e\n \u003cli\u003eGrunz JP, Gietzen CH, Christopoulos G, van Schoonhoven J, Goehtz F, Schmitt R, Hesse N. Osteoarthritis of the Wrist: Pathology, Radiology, and Treatment. Semin Musculoskelet Radiol. 2021 Apr;25(2):294-303. doi: 10.1055/s-0041-1730948. Epub 2021 Aug 9. PMID: 34374064.\u003c/li\u003e\n \u003cli\u003evan Saase JL, van Romunde LK, Cats A, Vandenbroucke JP, Valkenburg HA. Epidemiology of osteoarthritis: Zoetermeer survey. Comparison of radiological osteoarthritis in a Dutch population with that in 10 other populations. Ann Rheum Dis. 1989 Apr;48(4):271-80. doi: 10.1136/ard.48.4.271. PMID: 2712610; PMCID: PMC1003741.\u003c/li\u003e\n \u003cli\u003eAbramoff B, Caldera FE. Osteoarthritis: pathology, diagnosis, and treatment options. Med Clin North Am. 2020 Mar;104(2):293-311\u003c/li\u003e\n \u003cli\u003eLaulan J, Marteau E, Bacle G. Wrist osteoarthritis. Orthop Traumatol Surg Res. 2015 Feb;101(1 Suppl):S1-9. doi: 10.1016/j.otsr.2014.06.025. Epub 2015 Jan 14. PMID: 25596986.\u003c/li\u003e\n \u003cli\u003eKay J, Upchurch KS. ACR/EULAR 2010 rheumatoid arthritis classification criteria. Rheumatology (Oxford). 2012 Dec;51 Suppl 6:vi5-9. doi: 10.1093/rheumatology/kes279. PMID: 23221588.\u003c/li\u003e\n \u003cli\u003eDevaraj NK. The Atypical Presentation of Rheumatoid Arthritis in an Elderly Woman: A Case Report. Ethiop J Health Sci. 2019 Jan;29(1):957-958. doi: 10.4314/ejhs.v29i1.18. PMID: 30700964; PMCID: PMC6341435.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6534891/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6534891/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Rheumatoid arthritis (RA) is well-known for its inflammatory characteristics of pain, stiffness and swelling of the joint. Although it may result in any joint involvement, it usually affects the small joints in the hand, foot, wrist and shoulder. This case highlights an atypical presentation of RA which initially manifested as primary osteoarthritis (OA) with the absence of classic synovitis and emphasizes the importance in considering RA in the differential diagnoses especially, when symptoms involve joints that are atypical for OA.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase description:\u003c/strong\u003e In this case report, a man came for an outpatient assessment with pain and stiffness of bilateral knees, for which he was being treated for chronic OA. Two total knee replacements were performed resulting in satisfactory relief of symptoms. Surprisingly, he developed new symptoms of OA involving atypical joints for OA in the form of glenohumeral joint OA and OA at the distal radioulnar joint. Although the examination findings of synovitis were initially absent, the serological diagnosis of RA was later made.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e This case serves as a reminder that RA can mimic primary OA, and serological testing should be considered in cases with unusual joint involvement even in the absence of inflammatory signs.\u003c/p\u003e","manuscriptTitle":"Case report: Atypical presentation of rheumatoid arthritis that initially presented as osteoarthritis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-29 15:59:15","doi":"10.21203/rs.3.rs-6534891/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"bb37407e-d430-419d-9c7c-9a678ceb81b3","owner":[],"postedDate":"May 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-17T11:09:00+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-29 15:59:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6534891","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6534891","identity":"rs-6534891","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}