脊髄症を呈した胸椎椎間板ヘルニアの手術療法―後方アプローチによる顕微鏡下椎間板摘出術

Surgical Outcome of Posterior Approach in Patients with Thoracic Myelopathy Due to Disc Herniation

　目的：われわれは手術用顕微鏡を用いて胸椎の脊髄症を来した正中型あるいは傍正中型椎間板ヘルニアを後方アプローチにて摘出してきた．対象：対象は当科で後方アプローチにて椎間板を摘出した胸椎椎間板ヘルニア13例である．手術適応は脊髄症を呈したものとした．男性7名，女性6名で，年齢は33～70歳，平均49.2歳であった．結果：術中操作によると思われる麻痺の出現は1例もなく，術中出血量は平均108g，平均手術時間は2時間32分であった．後療法は術翌日から座位とし3日目より歩行練習を開始した．平均入院期間は17日であった．JOAスコアは6.1点から8.3点となり，平林の改善率は57.1％であった．

　Objectives：We have developed a new posterior approach using the operating microscope in surgery for central or paracentral thoracic disc herniation with myelopathy. We report here the surgical procedure and the clinical outcome.　Subjects：The present study includes 13 patients (7 males and 6 females, age 33-70 y. o., average 49.2 y. o.) with thoracic disc herniation in which the extruded disc fragments were removed via the posterior approach.　Results：No major complications such as paralysis were observed. The amount of intraoperative bleeding was 108 g on average and the duration of the operation was 2 hours and 32 minutes on average. Patients were allowed to sit on the next day and walking exercise was limited from post operation day 2. Hospitalized days were 17 on average. The JOA score was improved from 6.1 to 8.3 and Hirabayashi's improved ratio was 57.1％.　Discussion：The present study clearly demonstrates that the posterior approach with the above modification such as making enough space laterally and the use of the operationg microscope ensures safe operation.