Sasa Takahiro, Yoshizumi Yusuke, Imada Koichi, Aoki Masato, Terai Tomoya, Koizumi Tomofumi, Goel Vijay K, Faizan Ahmad, Biyani Ashok, Sakai Toshinori, Sairyo Koichi
Department of Orthopedic Surgery, Kurobe City Hospital, Kurobe, Japan.
Arch Orthop Trauma Surg. 2009 Apr;129(4):559-67. doi: 10.1007/s00402-008-0609-7. Epub 2008 Apr 24.
A case report and a biomechanical study using a finite element method.
To report a case with the cervical spondylolysis and to understand the biomechanics of the cervical spine with spondylolysis at C6. Cervical spondylolysis, although not a common spinal disorder, can occur in athletes. Presently, the exact pathology, natural history and biomechanics are not known. Thus, treatment strategies for this disorder in athletes are in controversy. To treat and/or advise patients with cervical spondylolysis, the cervical spine biomechanics regarding this disorder should be understood.
A case of a 12-year-old male judo player is presented. The patient presented with occipital and upper neck pain. Plain radiographs, reconstructed CT scan and MRIs of this patient were reviewed. Biomechanically, stress distributions were analyzed in response to 73.6 N axial compression and 1.5-Nm moment in flexion, extension, lateral bending, and axial rotation using a FE model of the intact ligamentous C3 to C7 segment. Bilateral spondylolysis was created in the model at C6. The stress results from the bilateral defect model were compared to the intact model predictions.
Plain radiographs showed bilateral C6 spondylolysis, and grade I spondylolisthesis. MRI showed mild disc degeneration at C6/7. With conservative treatment, the symptoms disappeared. In the spondylolysis model, the maximum Von Mises Stresses at C6/7 increased in all cervical spine motions, as compared to the intact case. Specifically, in axial rotation, the stress increase was 3.7-fold as compared to the intact model. The range of motion at C6/7 increased in the spondylolysis model as well. Again, during axial rotation, the increase in motion was 2.3-fold when compared to the intact model.
Cervical spondylolysis can cause biomechanical alterations, especially in axial rotation, leading to increased disc stresses and range of motion. The increased stresses in the disc and the hypermobility would be a dangerous condition for athletes participating in contact sports such as judo. Thus, we recommended that judo players with cervical spondylolysis should change to non-contact sports, such as jogging.
一份病例报告以及一项使用有限元方法的生物力学研究。
报告一例颈椎椎弓根峡部裂病例，并了解C6节段颈椎椎弓根峡部裂的生物力学情况。颈椎椎弓根峡部裂虽不是常见的脊柱疾病，但可发生于运动员。目前，其确切病理、自然病史及生物力学尚不清楚。因此，针对运动员该疾病的治疗策略存在争议。为了治疗和/或为颈椎椎弓根峡部裂患者提供建议，应了解该疾病相关的颈椎生物力学情况。
介绍一名12岁男性柔道运动员的病例。该患者表现为枕部和上颈部疼痛。回顾了该患者的X线平片、重建CT扫描和MRI检查结果。在生物力学方面，使用完整韧带连接的C3至C7节段的有限元模型，分析了在73.6 N轴向压缩以及1.5 N·m的前屈、后伸、侧弯和轴向旋转力矩作用下的应力分布情况。在模型中于C6处制造双侧椎弓根峡部裂。将双侧缺损模型的应力结果与完整模型的预测结果进行比较。
X线平片显示双侧C6椎弓根峡部裂及I度椎体滑脱。MRI显示C6/7节段轻度椎间盘退变。经保守治疗，症状消失。在椎弓根峡部裂模型中，与完整情况相比，C6/7节段在所有颈椎运动中的最大冯·米塞斯应力均增加。具体而言，在轴向旋转时，与完整模型相比应力增加了3.7倍。椎弓根峡部裂模型中C6/7节段的活动范围也增加了。同样，在轴向旋转时，与完整模型相比活动增加了2.3倍。
颈椎椎弓根峡部裂可导致生物力学改变，尤其是在轴向旋转时，导致椎间盘应力和活动范围增加。椎间盘应力增加和活动过度对参加柔道等接触性运动的运动员来说是一种危险情况。因此，我们建议患有颈椎椎弓根峡部裂的柔道运动员应改为参加非接触性运动，如慢跑。
