{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T18:21:30Z","timestamp":1785781290979,"version":"3.56.0"},"reference-count":13,"publisher":"BMJ","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Med Genet"],"published-print":{"date-parts":[[1995,4]]},"abstract":"<jats:p>We report on a 12 year old mentally retarded boy who presented at birth with bilateral knee dislocations, dislocation of the right hip, and general joint laxity. Cytogenetic studies showed a 49,XXXXY karyotype. Hyperlaxity of joints is known to occur in 49,XXXXY patients, but congenital knee dislocation has not been reported. Rarely in 49,XXXXY and 49,XXXXX syndromes Larsen-like features may be seen. Patients with congenital joint dislocation or laxity, combined with other malformations, especially if psychomotor development is delayed, should be karyotyped to exclude chromosomal abnormalities.<\/jats:p>","DOI":"10.1136\/jmg.32.4.309","type":"journal-article","created":{"date-parts":[[2008,11,10]],"date-time":"2008-11-10T15:23:16Z","timestamp":1226330596000},"page":"309-311","source":"Crossref","is-referenced-by-count":16,"title":["Congenital knee dislocation in a 49,XXXXY boy."],"prefix":"10.1136","volume":"32","author":[{"given":"R H","family":"Sijmons","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A J","family":"van Essen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J D","family":"Visser","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M","family":"Iprenburg","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G F","family":"Nelck","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M L","family":"Vos-Bender","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B","family":"de Jong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[1995,4,1]]},"reference":[{"key":"ref_1","first-page":"174","article-title":"Congenital dislocation of the knee","volume":"9","author":"Bensahel, H.; Dal Monte, A.; Hjelmsted, A.","year":"1989","unstructured":"Bensahel H, Dal Monte A, Hjelmsted A, et al. 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Z Kinderheilkd 1973;115:209-33."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1002\/ajmg.1320040402","article-title":"Pentasomy X with multiple dislocations","volume":"4","author":"Dryer, R.F.; Patil, SR, Zellweger; H.U.","year":"1979","unstructured":"Dryer RF, Patil SR, Zellweger HU, et al. Pentasomy X with multiple dislocations. Am Med Genet 1979;4:313-21.","journal-title":"Am Med Genet"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"587","DOI":"10.1007\/BF00209018","article-title":"Two unrelated children with partial trisomy lq and monosomy 6p, presenting with the phenotype of Larsen syndrome","volume":"87","author":"Pierquin, G.; Van Regemorter, N.; Hayez-Delatte","year":"1991","unstructured":"Pierquin G, Van Regemorter N, Hayez-Delatte, et al. Two unrelated children with partial trisomy lq and monosomy 6p, presenting with the phenotype of Larsen syndrome. 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Oxford: Oxford University Press, 1994."}],"container-title":["Journal of Medical Genetics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/jmg.32.4.309","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,18]],"date-time":"2025-10-18T07:59:58Z","timestamp":1760774398000},"score":1,"resource":{"primary":{"URL":"https:\/\/jmg.bmj.com\/lookup\/doi\/10.1136\/jmg.32.4.309"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1995,4]]},"references-count":13,"journal-issue":{"issue":"4","published-online":{"date-parts":[[1995,4,1]]},"published-print":{"date-parts":[[1995,4]]}},"alternative-id":["10.1136\/jmg.32.4.309"],"URL":"https:\/\/doi.org\/10.1136\/jmg.32.4.309","relation":{},"ISSN":["0022-2593","1468-6244"],"issn-type":[{"value":"0022-2593","type":"print"},{"value":"1468-6244","type":"electronic"}],"subject":[],"published":{"date-parts":[[1995,4]]}}}