Yoshihito Sakai1, Sadayuki Ito2, Tetsuro Hida3, Kenyu Ito3, Atsushi Harada2, Ken Watanabe4. 1. National Center for Geriatric and Gerontology, Department of Orthopaedic Surgery, Japan. Electronic address: jsakai@ncgg.go.jp. 2. National Center for Geriatric and Gerontology, Department of Orthopaedic Surgery, Japan. 3. Nagoya University School of Medicine, Department of Orthopaedic Surgery, Japan. 4. National Center for Geriatrics and Gerontology, Department of Bone and Joint Disease, Japan.
Abstract
BACKGROUND: The ligamentum flavum hypertrophy is considered to be one of the important causes of development of lumbar spinal stenosis (LSS). Several histologic and biologic mechanisms in hypertrophied flavum have proposed. However, no study that investigated the relationship between clinical outcome and ligamentum flavum hypertrophy has been published. The purpose of this study was to identify a new classification of LSS, in ligamentous and nonligamentous stenosis, according to the cutoff value of the area proportion of the ligamentum flavum in the spinal canal, and to assess the value of surgical and conservative treatments for LSS based on the classification of the ligamentous stenosis. METHODS: A total of 230 surgical patients with LSS were evaluated based on the cross-sectional area and intraoperative findings of the ligamentum flavum. LSS was classified as ligamentous or nonligamentous stenosis, according to the cutoff value of the proportion of the ligamentum flavum in the spinal canal. Based on the classification, the results of 234 surgical patients (103 patients with spinal fusion surgery and 131 patients with spinal decompression) and 191 patients under conservative treatment with prostaglandin E1 were evaluated, 1 year after treatments. RESULTS: ROC analysis revealed that the area under the curve for the cutoff value of the proportion of the ligamentum flavum in the spinal canal was 0.4275 (sensitivity = 0.861, specificity = 0.854). Based on these criteria, ligamentous and nonligamentous stenoses were 115 and 119 in surgical patients, 97 and 94 in conservative patients, respectively. In the surgical treatment group, no significant difference was found in any of the evaluations conducted for the group with ligamentous and nonligamentous stenosis. However, in the conservative treatment group, the patients with ligamentous stenosis showed significant improvement compared with patients with nonligamentous stenosis. CONCLUSIONS: Ligamentous stenosis in LSS patients had favorable outcome on conservative treatment with prostaglandin E1 derivative.
BACKGROUND: The ligamentum flavum hypertrophy is considered to be one of the important causes of development of lumbar spinal stenosis (LSS). Several histologic and biologic mechanisms in hypertrophied flavum have proposed. However, no study that investigated the relationship between clinical outcome and ligamentum flavum hypertrophy has been published. The purpose of this study was to identify a new classification of LSS, in ligamentous and nonligamentous stenosis, according to the cutoff value of the area proportion of the ligamentum flavum in the spinal canal, and to assess the value of surgical and conservative treatments for LSS based on the classification of the ligamentous stenosis. METHODS: A total of 230 surgical patients with LSS were evaluated based on the cross-sectional area and intraoperative findings of the ligamentum flavum. LSS was classified as ligamentous or nonligamentous stenosis, according to the cutoff value of the proportion of the ligamentum flavum in the spinal canal. Based on the classification, the results of 234 surgical patients (103 patients with spinal fusion surgery and 131 patients with spinal decompression) and 191 patients under conservative treatment with prostaglandin E1 were evaluated, 1 year after treatments. RESULTS: ROC analysis revealed that the area under the curve for the cutoff value of the proportion of the ligamentum flavum in the spinal canal was 0.4275 (sensitivity = 0.861, specificity = 0.854). Based on these criteria, ligamentous and nonligamentous stenoses were 115 and 119 in surgical patients, 97 and 94 in conservative patients, respectively. In the surgical treatment group, no significant difference was found in any of the evaluations conducted for the group with ligamentous and nonligamentous stenosis. However, in the conservative treatment group, the patients with ligamentous stenosis showed significant improvement compared with patients with nonligamentous stenosis. CONCLUSIONS: Ligamentous stenosis in LSS patients had favorable outcome on conservative treatment with prostaglandin E1 derivative.
Authors: Christian Barz; Markus Melloh; Lukas P Staub; Sarah J Lord; Harry R Merk; Thomas Barz Journal: Eur Spine J Date: 2017-02-04 Impact factor: 3.134
Authors: Ai-Min Wu; Kai Zhang; Xun-Lin Li; Xiao-Fei Cheng; Tang-Jun Zhou; Lin Du; Chen Chen; Hai-Jun Tian; Xiao-Jiang Sun; Chang-Qing Zhao; Yan Michael Li; Jie Zhao Journal: Quant Imaging Med Surg Date: 2018-05