雙層髕骨（Double-layered patella, DLP）在1925年由Büttner首先報道；是一種相對少見的常染色體隱性遺傳的疾病，是由軟骨發(fā)育不良畸形輸硫蛋白 (DiastrophicDysplasiaSulfateTransporter,DTDST)基因突變導(dǎo)致的多發(fā)性骨骺發(fā)育不良(Multiple Epiphyseal Dysplasia，MED)。臨床表現(xiàn)為雙側(cè)膝前反復(fù)發(fā)作性疼痛和早發(fā)性髖關(guān)節(jié)炎，可伴有輕度短指和馬蹄足的畸形。

      The double-layered patella (DLP) was first described by Büttner in 1925. It is a rare entity that is often associated with an autosomal recessive form of multiple epiphyseal dysplasia (MED) caused by a homozygous diastrophic dysplasia sulfate transporter (DTDST) gene mutation2, although COMP and COL9A2 deletions have also been reported to cause DLP. DLP is a relatively mild form of MED, and clinical findings are often limited to bilateral recurrent anterior knee pain and early-onset hip osteoarthritis (C653S homozygous DTDST gene) as well as mild brachydactyly and clubfoot deformity (R279W homozygous DTDST gene).                         ---JBJS Case Connect, 2013 May 22; 3 (2).

圖片來源  ---Pediatr Radiol. 2005 Feb;35(2):116-23