Spine Section, Department of Orthopaedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan.
J Clin Neurosci. 2010 Mar;17(3):320-4. doi: 10.1016/j.jocn.2009.06.023. Epub 2010 Jan 13.
We studied 27 patients with cervical ossification of the posterior longitudinal ligament (OPLL) but no clinical symptoms of myelopathy. We investigated the occupation ratio of the spinal canal by OPLL with cervical radiographs, assessed the morphological types of OPLL, and measured the segmental range of motion (ROM) at the level of maximum cord compression on flexion and extension radiographs. Patients were classified as having continuous-type OPLL (17 patients), mixed-type OPLL (seven patients), or segmental-type OPLL (three patients). The segmental ROM was negatively correlated with the OPLL occupation ratio (r=-0.49, p<0.01). No patient developed myelopathy during the study period. Three patients with massive OPLL did not develop myelopathy and the mobility of their cervical spine was highly restricted, suggesting that dynamic factors such as the segmental ROM preferentially contribute to the development of myelopathy in patients with cervical OPLL. Thus, by controlling the dynamic factors (hypermobility), we might be able to reduce neurological deterioration in patients with cervical OPLL.
我们研究了 27 例无脊髓病临床症状的颈椎后纵韧带骨化症（OPLL）患者。我们通过颈椎 X 线片研究了 OPLL 对椎管的侵占率，评估了 OPLL 的形态学类型，并在颈椎屈伸位 X 线片上测量了最大脊髓压迫水平的节段活动范围（ROM）。患者被分为连续型 OPLL（17 例）、混合型 OPLL（7 例）或节段型 OPLL（3 例）。节段 ROM 与 OPLL 侵占率呈负相关（r=-0.49，p<0.01）。在研究期间，没有患者发生脊髓病。3 例 OPLL 严重的患者没有发生脊髓病，颈椎活动度受到高度限制，这表明颈椎 OPLL 患者的节段 ROM 等动态因素可能优先导致脊髓病的发生。因此，通过控制动态因素（过度活动），我们或许可以减少颈椎 OPLL 患者的神经恶化。
