Achondroplasiaに合併した広範な脊椎管狭窄症の1例

A Case of Achondroplasia showing Diffuse Spinal Canal Stenosis

I．はじめに

　achondroplasiaは，内軟骨骨化障害により四肢短縮型小人症を示す比較的稀な先天異常である．脊椎管にも障害がみられ，congenital／developmental spinal canal ste—nosisを合併する代表疾患とされる．最近われわれは，胸腰部脊椎管狭窄症を伴う本奇形を経験し，手術により良好な結果を得たので若干の文献的考察を加えて報告する。

A rare case of achondroplasia showing diffuse spinal canal stenosis is presented. A 39-year-old woman was admitted to our hospital because of numbness of lower extremities and intermittent claudication. The patient's height was 121cm and she had the typical clinical fea-tures of an achondroplastic dwarf. Neurological ex-amination revealed spastic paraparesis, and sensory im-pairment below the level of T1.1 in the left side and LI in the right. A plain X-ray feature of the spine showed spinal canal stenosis. The interpedicular distances were short in all vertebrae, and especially more prominent in the caudal lumbar region. The sacrum laid horizontally and the sacral angle was narrower than normal case. Myelography and computed tomographic myelography demonstrated severe stenosis of the subarachnoid space at the level of T9-11. Laminectomy was performed from the inferior half of T9 to T11. The yellow liga-ments were prominently hypertrophic and these were removed as far as possible. Postoperatively, the weak-ness of the lower extremities was improved immediate-ly, but numbness remained. Five months after the op-eration, she suffered from urinary dysfunction, so furth-er laminectomy from T12 to L5 was performed. Also in this operation, hypertrophic yellow ligament was pathognomonic. Following this operation the patient had a good recovery course and returned to work.