Sakai Toshinori, Yamada Hidehiro, Nakamura Taro, Nanamori Kazuhisa, Kawasaki Yoshiteru, Hanaoka Naoyoshi, Nakamura Eijiro, Uchida Ken, Goel Vijay K, Vishnubhotla Lakshmi, Sairyo Koichi
Department of Orthopedic Surgery, Oita Nakamura Hospital, Otemachi, Japan.
Spine (Phila Pa 1976). 2006 Feb 1;31(3):E66-70. doi: 10.1097/01.brs.0000197650.77751.80.
Radiologic study for patients with athetoid cerebral palsy (CP), and a biomechanical study using the finite-element model (FEM).
To understand the lumbar disorders of athetoid CP patients and the etiology based on the results from the FEM study.
Cervical spondylotic myelopathy is a well-identified spinal disorder associated with cerebral palsy, especially in athetoid type. One can rationalize that the athetoid involuntary trunk movement may induce stress-related lumbar disorders. Until now, very few investigations have been conducted on lumbar disorders that could occur in patients with CP.
Sixty-one cases with athetoid cerebral palsy were clinically reviewed. Radiographs of the lumbar spine in 30 cases with low back pain were taken. From these radiographs, the incidence of lumbar spondylolysis and endplate lesion was analyzed. The biomechanical study was conducted using a three-dimensional FEM of the ligamentous lumbar spine. Axial compression of 400 N was applied to simulate preload on the spine during the standing position followed with 10.6 Nm moment to simulate extension and axial rotation. The combined motion of extension and axial rotation was also simulated. During supine position, pure extension and rotation were simulated, and no preload was applied. The von Mises stresses were computed at the pars interarticularis at the each level and compared for different motions.
Among the 61 patients, 41 complained of symptoms such as low back and leg pain. Thirty of these 41 patients gave their consents to undergo radiographic evaluation. Twenty-eight of the 30 patients (93.3%) showed stress-related disorders such as the spondylolysis and/or vertebral endplate lesions. Spondylolysis was found in 18 of the 30 patients (60.0%). Spondylolysis was observed at the multiple levels in 4 patients involving two levels in 2 cases and three levels in the other 2 cases. Vertebral endplate lesions (deformity) were seen in 26 (86.7%) of the 30 patients. Overall, the lesions (deformity) were found in 109 of 330 endplates (33.0%) out of all lumbar endplates in the 30 patients. The FEM based results showed that stresses at pars interarticularis of L5 were the highest of all levels in all loading modes, with or without preload. However, compared with the extension or axial rotation alone modes, the combined motion of extension and rotation showed higher stresses at the pars interarticularis.
The athetoid involuntary movements in CP patients may cause stress-related lumbar disorders. Especially, combined extension and rotation due to the involuntary trunk motion may contribute to the high incidence of spondylolysis.
对徐动型脑瘫（CP）患者进行放射学研究，并使用有限元模型（FEM）进行生物力学研究。
基于有限元模型研究结果，了解徐动型脑瘫患者的腰椎疾病及其病因。
脊髓型颈椎病是一种与脑瘫明确相关的脊柱疾病，尤其是在徐动型中。可以推断，徐动型的不自主躯干运动可能诱发与压力相关的腰椎疾病。到目前为止，针对脑瘫患者可能出现的腰椎疾病的研究非常少。
对61例徐动型脑瘫患者进行临床检查。对30例有腰痛的患者进行腰椎X线片拍摄。从这些X线片中分析腰椎峡部裂和终板病变的发生率。使用腰椎韧带的三维有限元模型进行生物力学研究。施加400 N的轴向压缩力以模拟站立位时脊柱的预负荷，随后施加10.6 Nm的力矩以模拟伸展和轴向旋转。还模拟了伸展和轴向旋转的联合运动。在仰卧位时，模拟单纯的伸展和旋转，不施加预负荷。计算每个节段关节突间部的冯·米塞斯应力，并比较不同运动时的应力。
61例患者中，41例主诉有腰腿痛等症状。这41例患者中有30例同意接受影像学评估。30例患者中有28例（93.3%）表现出与压力相关的疾病，如峡部裂和/或椎体终板病变。30例患者中有18例（占60.0%）发现有峡部裂。4例患者在多个节段出现峡部裂，其中2例涉及两个节段，另外2例涉及三个节段。30例患者中有26例（占86.7%）可见椎体终板病变（畸形）。总体而言，30例患者所有腰椎终板中，330个终板中有109个（占33.0%）发现病变（畸形）。基于有限元模型的结果表明，无论有无预负荷，在所有加载模式下，L5关节突间部的应力在所有节段中都是最高的。然而，与单纯伸展或轴向旋转模式相比，伸展和旋转的联合运动在关节突间部显示出更高的应力。
脑瘫患者的徐动型不自主运动可能导致与压力相关的腰椎疾病。特别是，由于不自主躯干运动导致的伸展和旋转联合运动可能导致峡部裂的高发生率。
