颈椎单开门椎管扩大成形术椎板开门角度对脊髓型颈椎病疗效的影响

目的:探讨椎板开门角度对颈椎单开门椎管扩大成形术(expansion of open-door laminoplasty)治疗脊髓型颈椎病疗效的影响。方法:选取我院2006年7月至2009年1月采用颈椎后路单开门椎管扩大成形术治疗并获得24个月以上随访的脊髓型颈椎病患者198例,男115例,女83例;年龄29～72岁,平均49±5岁。双节段39例(C3～C5 11例,C4～C6 28例);三个节段(C4～C7)97例,四个节段(C3～C7)62例。患者均有术前颈椎正侧位、双斜位和过度屈伸位X线平片和颈椎CT及MRI检查图片;术前JOA评分4～9分,平均6.3±2.9分。按照术后1周CT片上测量的椎板开门角度以30°为界限分为两组,统计两组手术时间、出血量、术后出现并发症病例、C2-C7 Cobb角度、颈椎前凸指数、颈椎活动度和脊髓后移数值,末次随访时评价患者神经功能情况,计算神经功能改善率。结果:开门角度>30°的患者共76例(A组);开门角度15°～30°的患者共122例(B组)。两组术前JOA评分、C2-C7 Cobb角度、颈椎前凸指数及颈椎活动度无显著性差异(P>0.05)。A组手术时间110±13min,出血量250±80ml;B组手术时间120±30min,出血量230±100ml,两组比较均无显著性差异(P>0.05)。术后A组51例(67.1%)出现轴性症状,8例(10.4%)发生C5神经根麻痹,1例(1.32%)颈椎轻度后凸畸形;B组37例(10.5%)出现轴性症状,3例(2.4%)发生C5神经根麻痹,4例(3.28%)发生关门,A组轴性症状和C5神经根麻痹的发生率高于B组,差异有显著性(P<0.05)。术后1个月脊髓后移值为0～7.95mm,平均2.41±0.46mm。末次随访时两组C2-C7 Cobb角度、颈椎前凸指数及颈椎活动度无显著性差异(P>0.05);JOA评分改善率A、B组分别为(72.1±11.7)%和(69.0±12.3)%,两组间比较无显著性差异(P>0.05)。结论:不同椎板开门角度术后神经功能改善率无显著性差异;将椎板开门角度控制在15°～30°轴性症状及C5神经根麻痹发生率较低,但应防止发生关门。

Effect of lamina open angles in expansion of unilateral open-door laminoplasty on the clinical results in treating cervical myelopathy

Objective:To evaluate and compare the relation between the efficacy and clinical results of expansion of open-door laminoplasty with different angles in lamina open-door.Method:198 cases were select from July 2006 to January 2009 who underwent posterior cervical unilateral open-door laminoplasty and received treatment for more than 24 months follow-up of patients with cervical myelopathy.There were 115 male cases and 83 female case with the mean age of 49±5 years(range,29-72 years).There were 39 double-segment cases,including 11 C3-C5 cases and 28 C4-C6 cases;97 three-segment(C4-C7) cases and 62 four segment(C3-C7) cases.All of these cases had cervical spine anterior-posterior and lateral,oblique and double-bit excessive flexion and extension cervical spine X-ray,CT and MRI.Preoperative JOA scores were 4 to 9,an average of 6.3±2.9.By CT scan after 1 week in accordance with the measurement on the angle of the lamina to 30° for the open boundaries,the cases were divided into two groups,to compare operation time,blood loss,postoperative complications,C2-C7 Cobb angle,index of cervical lordosis,cervical movement and to values after the shift,and evaluate the neurological function at final follow-up and calculate improvement rate of nerve function.Result:Group A:a total of 76 cases had an opening angle change>30°.Group B:a total 122 cases had an opening angle change 15°-30°.In preoperative JOA scores,C2-C7 Cobb angle,index of cervical lordosis,cervical movement between the two groups showed no statistically significant difference(P>0.05).The surgical time and blood loss in group A were 110±13min and 250±80ml,and in group B respectively 120±30min and 230±100ml,the difference was not statistically significant(P>0.05).In group A,51 patients after surgery(67.1%) had axial symptoms,8 patients(10.4%) with C5 nerve root palsy,1 patient(1.32%) with mild cervical kyphosis.In group B,37 cases(10.5%) had axial symptoms,3 patients(2.4%) with C5 nerve root palsy,4 patients(3.28%) with open door closed.The incidence of axial symptoms and C5 nerve palsy of group A was higher than that of group B,the incidence of postoperative complications between the two group wae more significant different(P<0.05).The improve rate of JOA scores in final follow-up was(72.1±11.7)% in group A and(69.0±12.3)% in group B,with no significant difference.The value of spinal cord after shift at 1 month follow-up is 0-7.95mm,average 2.41±0.46mm.C2-C7 Cobb angle,index of cervical lordosis,cervical movement between the two groups showed no statistically significant difference(P>0.05).Conclusion:Different lamina open angles in improve rate of neurological function after surgery are not significantly different.The changes of the opening angle controlled between 15°-30° will lower the incidence of C5 nerve root palsy and axial symptoms,but reclose should be prevent.