颈椎前路减压融合术后C5神经根麻痹

C5 palsy after anterior decompression and fusion of cervical spine

目的:观察和评估颈椎前路减压融合术后C5神经根麻痹的发生情况与预后。方法:2007年5月-2012年1月行颈椎前路减压植骨融合术且术前三角肌肌力正常、手术减压范围包含C4/5椎间隙的患者共121例,男65例,女56例,平均手术年龄64.2岁,其中脊髓型颈椎病45例,神经根型颈椎病32例,颈椎后纵韧带骨化症44例。观察术后患者肩及上臂的肌力、感觉情况,在术前CT上测量C4/5神经根管直径,观察术前MRI T2加权像上脊髓高信号区。C5神经根麻痹诊断标准为三角肌肌力降至3级或3级以下。结果:共6例患者术后出现C5神经根麻痹,其中三角肌肌力2级1例,3级5例;单侧三角肌及肱二头肌肌力下降5例,双侧1例,均伴有感觉障碍。1例为C4/5椎间隙减压,1例为C5椎体次全切,4例为2个节段以上减压。5例患者术前MRI T2像上观察到C5节段脊髓高信号区。6例患者随访1-4年,感觉恢复正常;其中2例(1例术前T2像脊髓高信号区范围较大、1例术后肌力下降至2级)肌力恢复至4级,4例恢复至5级,恢复时间为1-8个月,平均4个月。6例C5神经根麻痹患者颈椎JOA评分由术前10.8±1.1分改善至末次随访时16.2±1.3分,差异有统计学意义(P<0.05),术后1年患者自我满意度评价为40%-70%,平均55%。6例C5神经根麻痹患者术前C4/5神经根管直径为2.86±0.28mm,115例无麻痹组为3.18±0.39mm。121例患者中,术前C4/5神经根管直径≤3.0mm者53例,发生C5神经根麻痹4例(7.5%);>3.0mm者68例,发生C5神经根麻痹2例(2.9%),两组比较无统计学差异(P>0.05)。121例中,减压融合1-2个颈椎节段发生C5麻痹为2/82(2.4%),减压3个节段发生C5麻痹为4/39(10.2%),两组比较差异有统计学意义(P<0.05)。结论:颈椎前路减压融合术后可能出现C5神经根麻痹,但预后较好,保守治疗后肌力、感觉均可明显改善。

Objectives： To observe the clinical features and prognosis of C5 palsy after anterior decompres-sion and spinal fusion of cervical spine. Methods： Between May 2007 and January 2012, 121 patients with- out deltoid weakness underwent anterior cervical decompression and spinal fusion which included the level ofC4/5. The patients included 65 males and 56 females with a mean age of 64.2 years. The diagnoses were cervical spondylotic myelopathy（45 patients）, cervical spondylotic myeloradiculopathy（32 patients） and cervicalossification of posterior longitudinal ligament（44 patients）. The grade of manual muscle test（MMT） of deltoid and biceps braehii, the diameter of the C4/5 foramen on CT and the high signal changes in the spinal cord on T2-weighted MRI were measured and evaluated. In the present study, C5 palsy was defined as a deterio-ration of deltoid muscle by at least 2 grades in a standard MMT without aggravation of lower extremity func- tion. Results： 6 patients developed C5 palsy, 1 of them suffered from bilateral weakness of deltoid and bi- ceps brachii and 5 of them from unilateral. All presented with pain or numbness on the C5 enervation re- gion. One of them underwent the decompression of C4/5 and another orle underwent the corpectomy of C5, the rest of them underwent anterior multiple segment decompressions. The high signal changes in the spinal cord on T2-weighted MRI were found in all 5 patients suffering from C5 palsy. All patients were followed upfor 1-4 years. The grade of MMT recovered to 4-5 degree in 8 months after surgery, two of them recovered to 4 degree with a mean period of 4 months（range, 1-8 months）. The JOA score improved from 10.8±1.1 pre- operatively to 16.2±1.3 postoperatively, with significant difference. The rate of satisfaction of patients was 40%-70%（mean 55%）. The diameter of the C4/5 foramen in C5 palsy and no palsy was 2.86±0.28mm and 3.18±0.39mm respectively, which showed no statistical difference. In 53 cases with the diameter of C4/5 foramen less than 3.0mm, 4 cases developed C5 palsy. Only 2 cases in 68 cases with the diameter of C4/5 foramenmore than 3.0mm developed C5 palsy. Among 121 cases, less than 2 level decompression had the rate of C5 palsy of 2.4%（2/82）, while 3 level decompression had the rate of 10.2%（4/39）, which showed significant dif- ference（P〈0.05）. Conclusions： C5 palsy is the possibly complication after the anterior cervical decompres- sion, which has a good prognosis. Corresponding conservative intervention is effective.