ABE Ryoji Kasnetsu Hospital, Department of Orthopaedic Surgery, Head of Department, 整形外科, 部長 (30193014)
SAIKI Kunio Saitama Medical School, Medical Department, Lecturer, 医学部, 講師 (40215520)
|Budget Amount *help
¥2,700,000 (Direct Cost : ¥2,700,000)
Fiscal Year 1999 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 1998 : ¥1,400,000 (Direct Cost : ¥1,400,000)
As a method of safe and reliable decompression of the spinal cord for thoracic-OPLL myelopathy, the posterior approach was selected and its disadvantage, I.e., the insufficient degree of decompression caused by thoracic kyphosis, was improved by elimination of three major anatomical factors which inhibited the posterior shift of the thoracic spinal cord. They were: (1) longitudinal factor, I.e., anterior pulling effects of spinal cord segments, above and below OPLL, (2) longitudotransverse factor, I.e., holding-down effect of the parts of dura; mid-dorsal part and lateral part which extended into nerve-sheath, (3) transverse factor, I.e., anterior tethering effect of thoracic roots and denticular ligaments. Means of elimination of these factors were: (1) extensive cervicothoracic laminoplastic decompression, (2) longitudinal durotomy, (3) facetectomy and root-OPLL release. OPLL resection or anterior transfer was finally performed if necessary. These procedures were performed through staged posterior approaches in fifteen cases of thoracic OPLL-myelopathy. A mean age was 56 years (range: 42-68 years) and a mean follow-up was 42 months (range: 5-100 months). Neurology improved in all cases, with little postoperative complications. Radiological pictures proved the effectiveness of elimination of posterior-shift-inhibiting factors for the spinal cord decompression.