Clinical study on lumbar stenosis using computed tomography

의학과/석사[한글] 요추협착증은 1954년 Verbiest에 의해 발육부전성 척추협착증이 보고된 이래 많은 연구가 있었으나 진단과 치료에 제약이 많았다. 최근 수용성 조영제와 고해상 척추전산화단층 촬영기의 개발로 진단에 획기적인 발전을 가져와서 정확한 원인과 부위를 알 수 있게되어 수술후 더욱 좋은 치료결과를 기대할 수 있게 되었다. 저자는 1983년 3월부터 1987년 9월까지 연세대학교 의과대학부속 영동세브란스병원 신경외과에서 요추협착증으로 진단되어 수술을 받은 433예를 대상으로 고해상력의 전산화단층촬영기를 이용한 척추강 각 부위의 계측과 임상적 분석 및 수술결과를 추적조사하여 다 음과 같은 결론을 얻었다. 1. 남녀의 비는 1:1.3으로 여자에 많았다. 호발연령은 40대와 50대로서, 남자는 40대, 여자는 50대에서 가장 많았다. 2. 요추협착증의 원인으로서는 퇴행성 협착증이 78.2%로 가장 많았으며, 그 다음으로 퇴행성 척추전전위증이 17.2%이었고, 이밖에 분리성 척추전전위증(1.6%), 외인성 협착증(1.6%), 외상성 협착증(0.7%) 및 발육부전성 협착증(0.7%)의 순이었다. 3. 척추마디에 따른 발생부위별로 보면 한 부위에 발생된 경우가 가장 많았고(47.1%), 두부위 32.8% 및 세부위 이상 20.1%였다. 한 부위 발생시 L4/5에서 가장 많이 발생하였고(85.8%), 그 다음이 L5/S1(10.3%)이었다. 두부위에서 발생된 경우에는 L4/5-L5/S1에서 가 장 많았으며(71.8%), 그 다음이 L3/4-L4/L5 부위였다(26.1%). 4. 특징적인 임상증상으로는 만성요통과 하지에 신경성간헐적 파행이었다(65.6%). 신경학적 소견중에는 별이상 소견이 없는 것이 특징이었으나, 아킬레스건반사의 소실 또는 감소(73%)가 대부분이었고, 요추간판탈출증의 특징적인 소견인 하지거상검사에는 단지 10.3%만이 장해를 나타내었다. 5. 요추협착증의 진단시 spine CT나 CT myelography를 이용하여 척추협착증의 원인 및 상태, 마미신경 압박상태, 척추측와의 협착등을 정확히 파악하는 것이 매우 중요하다. 6. 척수조영술상 완전 또는 불완전폐쇄는 44.1%이었으며 다발성 협착에 의한 함몰소견을 보인 예는 55.9%이었다. 7. 척수전산화단층촬영상 후관절의 비후된 경우가 가장 많았으며(65.8%), 골각형성(37.1%), 황인대비후(21.7%), 후종인대 골화증(23.8%) 및 황인대 골화증(4.9%)등의 소견을 볼 수 있다. 8. 고해상 척추전산화 단층촬영상으로 퇴행성 요추협착증을 진단할 때 요추강의 전후직경은 큰 의의가 없었고, 오히려 경막낭의 단면적과 척추강의 단면적이 진단에 가장 좋은 지표가 되었다. 또한 경막낭의 전후직경이나 양측 관절면간의 거리도 진단에 도움을 주었다. 척추측와의 전후직경이 3mm이하인 경우 외측성측와 협착증이라고 진단할 수 있었다. 또한 제4요추와 제5요추에서 양측 황인대각 (yellow ligament angle, Y-angle)이 60°이하인 경우 중심성 협착증으로 진단할 수 있었다. 9. 퇴행성 척추전전위증은 전산화 단층촬영상 척추강과 경막낭의 전후직경과 단면적이 상하 추체부위보다 좁아져 있었으며, 이때는 황인대각(Y-angle)은 거의 정상이었다. 10. 수술은 광범위한 감압적 척추 후궁절제술과 관절면내측절제술 및 신경공감압절제술을 실시하여 좋은 결과를 얻었다. 11. 수술후 결과는 good과 excellent가 90.3%였고, fair와 poor는 9.7%이었다. Clinical study on lumber stenosis using computed tomography Yong Eun Cho Department of Medical Science, The Graduate School, Yonsei University (Directed by Prof. Young Soo Kim, M.D.) Since developmental lumbar stenosis was described by Verbiest in 1954, there have been many reports on lumbar stenosis. But there have been many limitations in diagnosis and treatment of lumbar stenosis. Recently, the development of water-soluble contrast media and high resolution spine CT scan have not only brought about significant progress in diagnosis of the etiology and levels of lumbar stenosis, but also better surgical therapetic results could be expected. The author has reviewed 433 patients with lumbar stenosis operated at the department of Neurosurgery YUMC Yongdong Severance hospital from March 1983 to September 1987 and analized the measurements of various parts of the spinal canal by high resolution spine CT scan, and evaluated the clinical courses and their surgical outcomes. The results were summarized as following: 1. Male to female ratio was 1:1.3. The peak age incidence were 40's in male and 50's in female. 2. By the causes of lumbar stenosis, degenerative stenosis was most common as 78%, and followed by degenerative spondylolisthesis 17.2%, spondylolytic spondylolisthesis(1.6%), iatrogenic stenosis(1.6%), developmental stenosis(0.7%) and posttraumatic stenosis(0.7%). 3. Single level stenosis was most common(47.1%), two levels 32.8% and three levels or more 20.1%. In the single level stenosis L4/5 was most common as 85.8% and L5/S 10.3%. In the two levels stenosis, L4/5 and L5/S1 was most common as 72.5% and L3/4 and L4/5 26.1%. 4. The characteristic clinical symptoms were chronic back pain and neurogenic intermittent claudication(65.6%). Few patient showed abnormal neurological findings. Common abnormal signs was loss or decrease of ankle jerk(73%). the straight leg raising test was not significant, and it was positive only in 10.3%. 5. In diagnosis of lumbar stenosis, it was most important to identify the causes of lumbar stenosis and degree of compression on cauda equina, or lateral recess stenosis by the spine CT or spine CT myelograms. 6. On myelogram, the findings of complete or incomplete block were present in 44.1%, and indentations of contrast dye column at the levels of stenosis in 55.9%. 7. The common findings on spine CT scan were hypertrophy of posterior articular facet joints(65.8%), osteophyte formation(37.1%), thicking of yellow ligament(21.7%), ossification of posterior longitudinal ligament(23.8%), ossification of yellow ligament(4.9%). 8. In the diagnosis of degenerative lumbar stenosis with high resolution of spine CT scan, anteroposterior diameter of spinal canal was not so significant, but the cross sectional areas of dural sac and spinal canal were most sensitive index. The anteroposterior diameter of dural sac and interfacetal distance provided the clue of lumbar stenosis,. If the anteroposterior diameter of the lateral recess was less than 3mm it could be diagnosed as the lateral recess stenosis. And if the angle between both ligaments(yellow ligament angle, Y-angle) was less than 60° it must be suspected as the central stenosis. 9. In the examination of degenerative spondylolisthesis with spinal Ct scan, anterior-posterior diameter and cross sectional area of spinal canal and dural sac were much more decreased than those of upper and lower vertebral levels. The angle of yellow ligament was almost normal. 10. For the definite treatment wide decompressive laminectomy medial facetectomy and foraminotomy should be carried out. 11. Out results of surgery were good to excellent in 90.3% and fair to poor 9.7%. [영문] Since developmental lumbar stenosis was described by Verbiest in 1954, there have been many reports on lumbar stenosis. But there have been many limitations in diagnosis and treatment of lumbar stenosis. Recently, the development of water-soluble contrast media and high resolution spine CT scan have not only brought about significant progress in diagnosis of the etiology and levels of lumbar stenosis, but also better surgical therapetic results could be expected. The author has reviewed 433 patients with lumbar stenosis operated at the department of Neurosurgery YUMC Yongdong Severance hospital from March 1983 to September 1987 and analized the measurements of various parts of the spinal canal by high resolution spine CT scan, and evaluated the clinical courses and their surgical outcomes. The results were summarized as following: 1. Male to female ratio was 1:1.3. The peak age incidence were 40's in male and 50's in female. 2. By the causes of lumbar stenosis, degenerative stenosis was most common as 78%, and followed by degenerative spondylolisthesis 17.2%, spondylolytic spondylolisthesis(1.6%), iatrogenic stenosis(1.6%), developmental stenosis(0.7%) and posttraumatic stenosis(0.7%). 3. Single level stenosis was most common(47.1%), two levels 32.8% and three levels or more 20.1%. In the single level stenosis L4/5 was most common as 85.8% and L5/S 10.3%. In the two levels stenosis, L4/5 and L5/S1 was most common as 72.5% and L3/4 and L4/5 26.1%. 4. The characteristic clinical symptoms were chronic back pain and neurogenic intermittent claudication(65.6%). Few patient showed abnormal neurological findings. Common abnormal signs was loss or decrease of ankle jerk(73%). the straight leg raising test was not significant, and it was positive only in 10.3%. 5. In diagnosis of lumbar stenosis, it was most important to identify the causes of lumbar stenosis and degree of compression on cauda equina, or lateral recess stenosis by the spine CT or spine CT myelograms. 6. On myelogram, the findings of complete or incomplete block were present in 44.1%, and indentations of contrast dye column at the levels of stenosis in 55.9%. 7. The common findings on spine CT scan were hypertrophy of posterior articular facet joints(65.8%), osteophyte formation(37.1%), thicking of yellow ligament(21.7%), ossification of posterior longitudinal ligament(23.8%), ossification of yellow ligament(4.9%). 8. In the diagnosis of degenerative lumbar stenosis with high resolution of spine CT scan, anteroposterior diameter of spinal canal was not so significant, but the cross sectional areas of dural sac and spinal canal were most sensitive index. The anteroposterior diameter of dural sac and interfacetal distance provided the clue of lumbar stenosis,. If the anteroposterior diameter of the lateral recess was less than 3mm it could be diagnosed as the lateral recess stenosis. And if the angle between both ligaments(yellow ligament angle, Y-angle) was less than 60° it must be suspected as the central stenosis. 9. In the examination of degenerative spondylolisthesis with spinal Ct scan, anterior-posterior diameter and cross sectional area of spinal canal and dural sac were much more decreased than those of upper and lower vertebral levels. The angle of yellow ligament was almost normal. 10. For the definite treatment wide decompressive laminectomy medial facetectomy and foraminotomy should be carried out. 11. Out results of surgery were good to excellent in 90.3% and fair to poor 9.7%.restrictio