Conservative treatment of mild ossification of cervical posterior longitudinal ligament: prognostic factors and timing of surgical repair

doi:10.3969/j.issn.2095-4344.2015.04.007

Abstract

Abstract:

BACKGROUND: The therapeutic effect of surgery is apparently better than conservative treatment for ossification of the posterior longitudinal ligament of moderate to severe spinal cord compression. However, patients with mild and slow developed ossification of the posterior longitudinal ligament do not have severe signs and symptoms of spinal cord compression in a long period. The superiority of surgery treatment has not been confirmed compared with the conservative treatment.

OBJECTIVE: To analyze the prognostic factors for patients with mild ossification of cervical posterior longitudinal ligament and to provide evidence for selecting timing of surgery patients with unfavourable prognosis after conservative treatment.

METHODS: Clinical information of 71 patients with mild ossification of cervical posterior longitudinal ligament, who were treated from January 2007 to January 2011, was prospectively analyzed. The Japanese Orthopedic Association score was at least 13 points. All patients received conservative management on admission. Prognostic factors that possibly affected conservative treatment were recorded. Follow-up was regularly conducted every 3 months after discharge. Neurological function of spinal cord was evaluated using Japanese Orthopedic Association score during follow-up of admission and discharge. Patients with increased symptom of spinal compression (Japanese Orthopedic Association score < 13 points; Japanese Orthopedic Association score decreased at least 2 points compared with initial hospitalization) underwent surgery treatment.

RESULTS AND CONCLUSION: At the end of February 2014, 67 patients completed more than 3-year follow-up. Only 19 patients with increased symptom of spinal compression received surgery treatment (surgery group). The remaining 48 patients received conservative treatment during follow up (conservative group). Statistical analysis indicated that patients with stenosis of cervical spinal canal and segmental instability have a poor prognosis of conservative treatment. There was no significant difference in Japanese Orthopedic Association score between surgery group and conservative group at first follow-up (P > 0.05). Japanese Orthopedic Association score was lower before surgery as compared with at the beginning of follow-up in the surgery group, showing significant differences (P < 0.05). Nevertheless, after surgery treatment, no significant difference in Japanese Orthopedic Association score was detected during final follow-up between the surgery and conservative groups (P > 0.05). These results confirmed that conservative treatment is still the first choice for mild ossification of cervical posterior longitudinal ligament. Stenosis of cervical spinal canal and segmental instability are the influencing factor for poor prognosis of conservative treatment. Once the spinal compression is worse during conservative treatment, timely surgical treatment is effective for patients with poor prognostic factors.

中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程

全文链接：

Key words: Cervical Vertebrae, Ossification of Posterior Longitudinal Ligament, Prognosis, Internal Fixators, Follow-Up Studies

CLC Number:

R318

Shen Cang-hai, Feng Yong-jian, Wang Li-guo, Yang Cheng, Peng Ning-ning, Wang Gui-jiang, Guo Xu . Conservative treatment of mild ossification of cervical posterior longitudinal ligament: prognostic factors and timing of surgical repair[J]. Chinese Journal of Tissue Engineering Research, 2015, 19(4): 531-536.

Figures/Tables 3

2.1 参与者数量分析 71例轻度颈椎后纵韧带骨化症患者中3例患者失访，1例患者因随访期间创伤致颈髓损伤，其余67例患者获得完整随访，随访时间37-55个月。保守组患者48例随访期间始终接受保守治疗。手术组患者19例保守治疗期间效果不佳，JOA评分平均降低2.7分(2- 5分)，接受颈椎前路或后路手术治疗。手术组从随访开始到手术的平均时间27.5个月(19-44个月)。 2.2 保守组与手术组基线资料比较保守组与手术组患者性别、首次住院时年龄、病程比较差异无显著性意义(P > 0.05)，具有可比性(表1)。 2.3 保守治疗的预后因素分析为了得出保守治疗的预后不良因素，对比保守组与手术组的主要观察指标 (见表1)，保守组与手术组颈椎管矢状径差异有显著性意义(t=3.229，P=0.005)，手术组患者椎管矢状径明显小于保守组。保守组23%患者颈椎节段不稳，治疗组53%患者颈椎节段不稳，差异有显著性意义(χ2=6.782，P=0.009)。保守组与手术组患者年龄、性别、病程、颈椎曲度、脊髓压迫率、脊髓高信号、骨化物范围、骨化物分型差异均无显著性意义(P > 0.05)。颈椎管矢状径较窄、颈椎不稳是保守治疗的预后不良因素。在保守治疗期间颈椎管矢状径较窄或颈椎不稳的患者往往保守治疗效果不佳，预后不良，最终接受手术治疗。 2.4 保守组与手术组首次住院与末次随访时JOA评分比较首次住院时保守组与手术组JOA评分差异无显著性意义(t=0.429，P=0.673)；末次随访时保守组与手术组JOA评分差异无显著性意义(t=1.561，P=0.236)。手术组患者术前3 d JOA评分为(11.4±1.1)分，术前3 d与首次住院时比较差异有显著性意义(t=5.461，P < 0.01)；手术组经过及时的手术干预后，末次随访时JOA评分与术前3 d比较差异有显著性意义(t=4.191，P=0.01，见表2)。"

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