ABSTRACT
<p><b>OBJECTIVE</b>To explore the reason of postoperative axial pain (PAP) complication caused by unilaterally open-door cervical laminoplasty with Centerpiece mini-plate fixations for the treatment of multilevel cervical spondylotic myelopathy(CSM).</p><p><b>METHODS</b>The clinical data of 79 patients with CSM who underwent unilaterally open-door cervical laminoplasty from January 2010 to December 2013 were retrospectively analyzed. There were 45 males and 34 females, aged from 48 to 75 years old with an average of (58.7±4.4) years, complicated with ossified posterior longitudinal ligament(OPLL) of 42 cases. Courses of disease were from 2.1 to 3.9 years with an average of (3.0±0.4) years. Decompression segment occurred in C₃-C₆ of 31 cases, C₃-C₇ of 9 cases, C₄-C₇ of 39 cases. The condition of PAP was record. Cervical curvature index, cervical lordosis angle, the rate of cervical instability, the motion of flexion and extension between PAP group and non-PAP group were compared preoperatively. Multivariate non-linear regression analysis was used to verify relationship between aforementioned parameters and incidence of PAP. JOA score of preoperative, postoperative 6 months and initial onset of PAP, the improvement rate of JOA score and Odom criteria at final follow-up were used to evaluate curative efficacy.</p><p><b>RESULTS</b>All the patients were followed up from 26 to 44 months with an average of (36±9) months. Among them, 12 patients occurred PAP who receive the conservative treatment. The rate of preoperative cervical instablility of PAP group were higher than that of non-PAP group(<0.05). Preoperative cervical instability was the only independent risk factor in predicting occurrence of PAP. There were no significant differences in cervical curvature, cervical lordosis index, the motion of flexion and extension between PAP and non-PAP group before operation. There were no significant differences in the improvement of nerve function and clinical effect between PAP and non-PAP group after operation(>0.05).</p><p><b>CONCLUSIONS</b>Preoperative cervical instability is prone to inducing the respectively intervertebral motion disorder and imbalance of stress redistribution, which results in PAP after cervical unilateral laminoplasty. Correct treatment of preoperative cervical instability is a key factor to prevent the occurrence of PAP after cervical laminoplasty, which would not affect long-term nerve functional recovery pronouncedly.</p>
ABSTRACT
Objective To propose the three heights of intervertebral disc during cervical disc degeneration by measuring the cervical intervertebral disc heights in patients with cervical spondylosis. Methods Totally 96 patients with cervical spondylosis undergoing surgery in our hospital from Jan. 2017 to May 2017 were enrolled in this study, and their intervertebral disc heights of C2-7 were measured by the lateral X-ray. The patients were divided into 3 groups according to the Pfirrmann score: anatomical height group (Pfirrmann score-Ⅱ grade without height loss), natural height group (Pfirrmann score III grade), and pathological height group (Pfirrmann score -grade with moderate and severe intervertebral height loss). Two-way ANOVA and LSD analysis were performed to compare the intervertebral disc heights between the three groups. Results The average age of 96 patients was (53.4±19.6) years old, with 57 males and 39 females. Fifty-nine cases were diagnosed with cervical spondylotic myelopathy, 25 with nerve root type cervical spondylosis, and 12 with mixed cervical spondylosis. The average intervertebral disc heights in the anatomic height, natural height and pathological height groups were (7.7±1.2) mm, (7.1±0.9) mm and (5.9±1.0) mm, respectively, and there were significant differences between the three groups (all P<0.01). The cut-off values (sensitivity, specificity) of the anatomical heights and natural heights, natural heights and pathological heights of C3-4, C4-5, C5-6 and C6-7 were 7.45 mm (0.62, 0.65) and 6.95 mm (0.63, 1.00), 7.75 mm (0.49, 0.85) and 6.10 mm (0.89, 0.43), 7.75 mm (0.59, 0.77) and 6.95 mm (0.66, 0.91), and 7.85 mm (0.61, 0.89) and 5.95 mm (0.86, 0.73), respectively. Conclusion During the process of degeneration, cervical disc height can be classified as anatomical height, natural height (degenerative height) and pathological height. We should pay attention to the intervertebral disc height before operation and suggest to restore natural disc height.
ABSTRACT
Objective: To investigate the prevalence and clinical significance of Modic changes in endplates of cervical vertebral body in patients with cervical spondylotic myelopathy(CSM). Methods: The T1-weight and T2-weight sagittal MRI scans of 136 CSM patients undergoing anterior operation were retrospectively reviewed. The patients' age, gender, prevalence, precise vertebral levels and specific type of Modic changes were recorded, and the association of axial pain with Modic changes was analyzed. Results: Modic changes were observed in 23 patients (16.9%), including 17(17.7%) male and 6(15%) female. The most frequent cervical spinal levels of Modic changes was C5-6. Of all the patients, 4.4% had type I Modic change, 7.4% had type II, and 5.1% had type III. The incidence of axial pain was 56.5% in Modic change groups and 20.4% in non-Modic change groups; there was significant difference between the two groups (P0.05). The pre-operation incidences of axial pain in patients with type I, type II and type III Modic change were 83.3%, 60% and 28.6%, respectively; and the post-operation pain-relieving rates were 100%, 66.7% and 50%, respectively. Conclusion: The most common Modic change is type II in the cervical spine, with the C5-6 level being the most frequently involved. The incidence of axial pain is high in patients with Modic change, especially those with type I.