モルキオ症候群に合併した強直性脊椎骨増殖症の1例

Ankylosing Spinal Hyperostosis in a Patient with Morquio Syndrome. Case Report

　モルキオ症候群はムコ多糖症の一種で，体内にムコ多糖が蓄積することで様々な症状を引き起こす比較的稀な疾患である．モルキオ症候群に合併する脊椎疾患として環軸椎不安定性が多く報告されているが，渉猟し得た範囲では後縦靱帯骨化症(OPLL)の報告はない．今回，強直性脊椎骨増殖症を合併したモルキオ症候群の患者で，頚胸椎のOPLLに対して手術を行った症例を経験したので報告する．またモルキオ症候群とOPLLはともに軟骨内骨化異常との関連が報告されており，OPLLの発生機序に関しても考察を加える．

　Morquio syndrome is one of the mucopolysaccharidoses.　It is a relatively rare disease, and is characterized by a variety of symptoms caused by mucopolysaccharide accumulation in the body.　Atlantoaxial instability is often reported as a spinal complication of Morquio syndrome, but as far as we were able to determine in a search of the literature ossification of the posterior longitudinal ligament (OPLL) has never been reported.　We report a case of ankylosing spinal hyperostosis in a patient with Morquio syndrome in which we performed surgery to treat cervicothoracic OPLL.　In addition, both Morquio syndrome and OPLL have been reported to be associated with atypical enchondral ossification, and we discuss the pathogenetic mechanism of OPLL.