臼蓋形成不全における潜在性二分脊椎の検討

Association of the Acetabular Displasia of the Hip with Spina Bifida Occulta

　本邦における臼蓋形成不全と潜在性二分脊椎の関係について検討した．対象は寛骨臼移動術を行った臼蓋形成不全223例(以下AD群)(全例女性，平均年齢39歳)であり，産婦人科手術例167例(平均年齢36歳)を対照群とした．2群の潜在性二分脊椎の合併率について調査した．潜在性二分脊椎の合併率はAD群23.3％，対照群8.4％であった(p＜0.01)．臼蓋形成不全の発生には遺伝的要因による腰仙椎から骨盤にかけての形成不全の可能性があることが示唆された．

　Spina bifida occulta (SBO) is sometimes seen on preoperative pelvic radiographs of transpositional acetabular osteotomy, but an association between acetabular dysplasia (AD) has not yet been well documented.　The present investigation was designed to assess the association between SBO and AD.　Subjects were 223 AD patients (AD group), and, 167 patients who had undergone obstetrical or gynecological surgery served as a control group.　We examined the radiographs and calculated the frequency of SBO in the two groups, and the results showed that the frequency of SBO in the AD group was significantly higher (23.3%) than in the control group (8.4%) (p＜0.01).　Based on the radiological fact that SBO is fairly common in patients with AD, there seems to be one group in the AD group in which skeletal hypoplasia from the lumbosacral spine to the pelvic and hip joint occurred during gestation because of genetic or other factors.