陳旧性環軸椎回旋位固定の治療成績―環椎後頭関節病変は難治化要因となりうる

Treatment for Chronic Atlantoaxial Rotatory Fixation. Pathological Change in a Atlanto-Occipital Joint as an Intractable Factor

　背景：環軸椎回旋位固定(AARF)は保存治療が一般に有効であるが，陳旧例の中に保存治療に抵抗する難治例が存在する．

　対象と方法：発症から1カ月以上経過した陳旧性AARF7例に対し，非観血的整復・直達牽引・ハローベスト外固定による治療を行った．われわれはその治療成績について，特に環椎後頭関節病変に着目して検討を行った．

　結果：環軸椎関節の整復が7例中5例で得られたが，初診時CTで環椎後頭関節亜脱臼・環椎後頭関節変形を呈した2例は整復不能であった．

　まとめ：環椎後頭関節病変の存在は，陳旧性AARF難治化要因の一つである．

　Background：Many cases of atlantoaxial rotatory fixation (AARF) can be successfully treated conservatively.　However, there are also intractable cases of chronic AARF that are resistant to conservative treatment.

　Methods：Seven patients with chronic AARF were treated by a combination of closed reduction under general anesthesia, skull traction, and halofixation.　The clinical outcomes and radiographic studies of these chronic AARF patients were reviewed retrospectively with a focus on pathological changes in the atlanto-occipital joint.

　Results：Chronic AARF was successfully reduced in five patients.　Reduction was impossible in the two patients who were observed to have a subluxation and deformity of the atlanto-occipital joint on their initial 3-dimensional computed tomography scans.　One of these two patients has been followed up untreated, and the other patient was treated surgically.

　Conclusions：A pathological change in the atlanto-occipital joint is an intractable factor in chronic AARFs.