Yamada Tsuyoshi, Shindo Shigeo, Yoshii Toshitaka, Ushio Shuta, Kusano Kazuo, Miyake Norihiko, Arai Yoshiyasu, Otani Kazuyuki, Okawa Atsushi, Nakai Osamu
Department of Orthopaedic Surgery, Kudanzaka Hospital, 1-6-12 Kudan- minami, Chiyoda-ku, 102-0074, Tokyo, Japan.
Department of Orthopaedic Surgery, Graduate School, Tokyo Medical and Dental University, Tokyo, 113-8510, Japan.
BMC Musculoskelet Disord. 2021 Jan 4;22(1):7. doi: 10.1186/s12891-020-03905-y.
Thoracic ossification of ligamentum flavum (T-OLF), as one of the causes of thoracic myelopathy, is often combined with other spinal disorders. Concurrent lumbar spinal canal stenosis (LCS) is often obscured by symptoms due to T-OLF, leading to difficulty in identifying the origin of these neurological findings. It is common to be misdiagnosed or delayed diagnosis due to the complicated nature. We evaluated the prevalence, distribution, and clinical characteristics of OLF, especially in patients with LCS.
The authors performed a retrospective analysis of the outcomes of 61 patients who underwent thoracic surgeries performed for symptomatic T-OLF. In all the patients, whole spine lesions were evaluated preoperatively. We examined the factors related to poor outcomes (the recovery rate of the Japanese Orthopedic Association score for thoracic myelopathy is less than 40%) following OLF surgeries. We compared the clinical outcomes according to whether there was concurrent LCS, and determined the optimal surgical approach.
The occurrence of T-OLF increased with age. Forty-six cases (75.4%) were considered to be tandem T-OLF and LCS (LCS group). An advanced age, and concurrent LCS were associated with a poor outcome after the surgery. The LCS group significantly included a greater number of elderly, and more light-weighted patients with Modic change in thoracic spine and a greater sagittal vertical axis, resulting in the lower neurological recovery. Additional lumbar surgery (13cases) effectively improved both the T-JOA and L-JOA scores (from 6.5 ± 2.0 points to 8.0 ± 1.8 points, p = 0.0406, and from 14.5 ± 4.7 points to 20.7 ± 2.6 points, p = 0.001, respectively) in OLF patients with LCS.
T-OLF was highly associated with other spinal disorders. Poor outcomes in T-OLF surgery could be associated with age and concurrent LCS, and an additional surgery for another lumbar lesion significantly improved neurological findings in T-OLF patients.
胸椎黄韧带骨化（T-OLF）是胸髓病的病因之一，常与其他脊柱疾病合并存在。同时存在的腰椎管狭窄（LCS）常被T-OLF的症状所掩盖，导致难以确定这些神经学表现的根源。由于其复杂性，误诊或延迟诊断很常见。我们评估了黄韧带骨化的患病率、分布及临床特征，尤其是在LCS患者中。
作者对61例因有症状的T-OLF而接受胸椎手术的患者的手术结果进行了回顾性分析。所有患者术前均评估了全脊柱病变情况。我们检查了黄韧带骨化手术后预后不良（胸髓病日本骨科协会评分恢复率低于40%）的相关因素。我们根据是否合并LCS比较了临床结果，并确定了最佳手术方式。
T-OLF的发生率随年龄增长而增加。46例（75.4%）被认为是串联性T-OLF和LCS（LCS组）。高龄和合并LCS与术后不良预后相关。LCS组明显包括更多老年患者、更多体重较轻且胸椎有Modic改变和矢状垂直轴更大的患者，导致神经功能恢复较差。额外的腰椎手术（13例）有效改善了LCS的OLF患者的胸段日本骨科协会（T-JOA）和腰段日本骨科协会（L-JOA）评分（分别从6.5±2.0分提高到了到8.0±1.8分，p = 0.0406；从14.5±4.7分提高到20.7±2.6分，p = 0.001）。
T-OLF与其他脊柱疾病高度相关。T-OLF手术预后不良可能与年龄和合并LCS有关，针对另一个腰椎病变进行的额外手术显著改善了T-OLF患者的神经学表现。
