{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T16:26:53Z","timestamp":1790872013062,"version":"4.1.0"},"reference-count":33,"publisher":"Springer Science and Business Media LLC","issue":"11","license":[{"start":{"date-parts":[[2021,4,10]],"date-time":"2021-04-10T00:00:00Z","timestamp":1618012800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,4,10]],"date-time":"2021-04-10T00:00:00Z","timestamp":1618012800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Universit\u00e4tsklinikum Hamburg-Eppendorf (UKE)"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Arch Orthop Trauma Surg"],"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Introduction<\/jats:title><jats:p>Osteoarthritis (OA) and rheumatoid arthritis (RA) represent the most common forms of arthritis, which are mainly caused by mechanical and inflammatory components, respectively. Determination of synovial inflammation in synovial biopsies via the histopathological Krenn score may be crucial for correct diagnosis and treatment. Specifically, it remains unclear whether synovitis scores differ among multiple biopsy locations within a single joint.<\/jats:p><\/jats:sec><jats:sec><jats:title>Materials and methods<\/jats:title><jats:p>Eighty synovial samples were taken from four standardized regions of the knee in 20 patients (ten primary OA, ten secondary OA) undergoing total knee arthroplasty (TKA) or total synovectomy. The Krenn synovitis score (grade 0\u20139) was determined in a blinded manner by two expert pathologists in all biopsies. Next to the inter-rater reliability, we evaluated the agreement of the determined scores among the four biopsy locations within each knee.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The inter-rater reliability between the two pathologists was very high (Cohen\u2019s kappa\u2009=\u20090.712;<jats:italic>r<\/jats:italic>\u2009=\u20090.946; ICC\u2009=\u20090.972). The mean synovitis score was significantly higher in knees with secondary than in primary OA (<jats:italic>p<\/jats:italic>\u2009=\u20090.026). Importantly, we found clear differences between the scores of the four different biopsy\u00a0locations within the individual knee joints, with an average deviation of 10.6%. These deviations were comparable in knees with primary and secondary OA (<jats:italic>p<\/jats:italic>\u2009=\u20090.64).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>While we confirmed the synovitis score as a reliable and reproducible parameter to assess the histopathological synovitis grade in the knee, the considerable variability within the joint indicates that multiple synovial biopsies from different regions should be obtained to enable reliable results of the synovitis score.<\/jats:p><\/jats:sec>","DOI":"10.1007\/s00402-021-03889-x","type":"journal-article","created":{"date-parts":[[2021,4,10]],"date-time":"2021-04-10T15:03:32Z","timestamp":1618067012000},"page":"2991-2997","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["The histopathological synovitis score is influenced by biopsy location in patients with knee osteoarthritis"],"prefix":"10.1007","volume":"142","author":[{"given":"Haider","family":"Mussawy","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jozef","family":"Zustin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas M.","family":"Luebke","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9","family":"Strahl","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Veit","family":"Krenn","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfgang","family":"R\u00fcther","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1058-1307","authenticated-orcid":false,"given":"Tim","family":"Rolvien","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,4,10]]},"reference":[{"issue":"23","key":"3889_CR1","doi-asserted-by":"publisher","first-page":"2205","DOI":"10.1056\/NEJMra1004965","volume":"365","author":"IB McInnes","year":"2011","unstructured":"McInnes IB, Schett G (2011) The pathogenesis of rheumatoid arthritis. 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According to \u00a7 12 \u201cForschungsvorhaben und Sammlungen von Proben Hamburgisches Krankenhausgesetz (HmbKHG)\u201d the anonymized collection of samples in the course of standard surgical procedures (\u201csurgical waste\u201d) is allowed. Additional ethics approval was therefore not required.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}}]}}