{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T08:41:26Z","timestamp":1782895286881,"version":"3.54.5"},"reference-count":6,"publisher":"SAGE Publications","issue":"4","license":[{"start":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T00:00:00Z","timestamp":1770076800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Sports Health: A Multidisciplinary Approach"],"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:p>Tenosynovial giant cell tumor (TGCT), formerly pigmented villonodular synovitis (PVNS), may extend into the popliteal fossa and mimic a Baker cyst, complicating diagnosis and operative planning. A 53-year-old former endurance runner presented with posterior knee pain, swelling, intermittent locking, and a palpable popliteal mass. Examination demonstrated effusion and limited range of motion; weightbearing radiographs showed mild osteoarthritic change with effusion, and magnetic resonance imaging (MRI) revealed synovial hypertrophy with low T2 signal suggestive of hemosiderin deposition. Arthroscopic synovectomy via 4 anterior and 2 posterior portals was performed; histology confirmed diffuse, nonmalignant TGCT. Given persistent posterior disease, a staged posterior open approach (lazy-S incision) enabled en bloc excision of the extra-articular component. Adjuvant radiosynoviorthesis (intra-articular yttrium-90) was administered. At 8-year follow-up, there was no clinical or radiographic evidence of disease. This case emphasizes MRI recognition of hemosiderin-related low T2 signal, the value of combining arthroscopic synovectomy with posterior open excision in diffuse disease with popliteal extension, and selective use of adjuvant radiosynoviorthesis for durability.<\/jats:p>","DOI":"10.1177\/19417381251410244","type":"journal-article","created":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T04:17:13Z","timestamp":1770178633000},"page":"898-900","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["Posterior Knee TGCT (Formerly PVNS) Masquerading as a Popliteal Lesion: Combined Arthroscopic Synovectomy and Posterior Open Excision With 8-Year Disease-Free Follow-Up"],"prefix":"10.1177","volume":"18","author":[{"given":"Ioannis","family":"Kougioumtzis","sequence":"first","affiliation":[{"name":"Department of Orthopaedic and Sports Traumatology - Arthroscopy, General Hospital of Nikaia Peiraia \u201cAgios Panteleimon,\u201d Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6102-3344","authenticated-orcid":false,"given":"Platon","family":"Papageorgiou","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Attikon University General Hospital (General University Hospital Attikon), Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1428-8394","authenticated-orcid":false,"given":"Dimitrios","family":"Kanakis","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of Nicosia Medical School, Nicosia, Cyprus"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nikolaos","family":"Ververidis","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Democritus University of Thrace, Komotini, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stylianos","family":"Tottas","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics\/Orthopaedic Surgery, General University Hospital of Alexandroupolis, Alexandroupoli, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nikolaos","family":"Gravvanis","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic and Sports Traumatology - Arthroscopy, General Hospital of Nikaia Peiraia \u201cAgios Panteleimon,\u201d Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Efthimios","family":"Iliopoulos","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics\/Orthopaedic Surgery, General University Hospital of Alexandroupolis, Alexandroupoli, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George","family":"Drosos","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Attikon University General Hospital (General University Hospital Attikon), Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9438-0558","authenticated-orcid":false,"given":"Andreas","family":"Stamatis","sequence":"additional","affiliation":[{"name":"Sports Medicine Institute, University of Louisville Health, Louisville, Kentucky"},{"name":"Department of Health and Sport Sciences, University of Louisville, Louisville, Kentucky"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2026,2,3]]},"reference":[{"key":"e_1_3_3_2_2","doi-asserted-by":"publisher","DOI":"10.1007\/s11999-012-2589-8"},{"key":"e_1_3_3_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.arthro.2012.02.007"},{"key":"e_1_3_3_4_2","doi-asserted-by":"publisher","DOI":"10.2106\/JBJS.ST.21.00035"},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.2106\/JBJS.ST.21.00051"},{"key":"e_1_3_3_6_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.knee.2017.03.011"},{"key":"e_1_3_3_7_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00256-006-0249-3"}],"container-title":["Sports Health: A Multidisciplinary Approach"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/19417381251410244","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/19417381251410244","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/19417381251410244","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T07:41:50Z","timestamp":1782891710000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/19417381251410244"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,3]]},"references-count":6,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2026,7]]}},"alternative-id":["10.1177\/19417381251410244"],"URL":"https:\/\/doi.org\/10.1177\/19417381251410244","relation":{},"ISSN":["1941-7381","1941-0921"],"issn-type":[{"value":"1941-7381","type":"print"},{"value":"1941-0921","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,3]]}}}