N. N. C. rodを使ったGrafバンドによる後方経路腰椎椎体間固定術（PLIF）隣接椎間制動術―2年以上経過例の検討

Segmental Morbidity at the Adjacent PLIF Level after Graf Ligamentoplasty Combined with N. N. C. rod after a Minimum 2-year Follow-up

　目的：PLIFの隣接椎間に狭窄があり，除圧術にGraf制動術を併用した成績を検討する．対象および方法：術後2年以上経過した15例を対象とした．PLIF椎間は変性すべり症12例．Graf椎間の可動域，すべりおよび椎間板高を術前と最終経過観察時にX線像にて測定した．結果：Graf椎間の術後可動域は，術前可動域が10°以上であったものほど減少した．Grafバンドの逸脱を生じた2例の可動域は不変であった．2例で可動域が消失した．結語：Graf椎間は可動域が減少し，局所後弯が低下する制動効果が得られた．

　Objective：To report clinical and radiographic segmental morbidity at the adjacent PLIF level after Graf ligamentoplasty combined with an NNC rod. Materials and Methods：Data from fifteen patients who underwent adjacent level Graf ligamentoplasty were reviewed retrospectively. The minimum follow-up period was 2 years. PLIF was peformed at twelve sites of degenerative spondylolisthesis. Clinical and radiographic assessments were performed before surgery and at the final follow-up. The radiographic evaluation included assessment of range of motion (ROM), flexion and extension angle, slip, and disc height. Result：The postoperative ROM had decreased at the Graf ligamentoplasty level, especially those whose preoperative ROM was 10 degrees or more. ROM did not change after surgery in two patients in whom the Graf band dislodged. In two patients the Graf ligamentoplasty fused spontaneously. Conclusion：Graf ligamentoplasty decreased ROM and the flexion angle.