扩大后壁减压术治疗颈椎后纵韧带骨化

Enlarged laminectomy for ossification of the posterior longitudinal ligament in the cervical spine

目的 介绍扩大后壁减压术（显露根袖起始部）治疗颈椎后纵韧带骨化（ossification of the posterior longitudinal ligament,OPLL）合并脊髓病,并探讨其疗效.方法 1998年1月至2005年12月,采用扩大后壁减压手术治疗颈椎OPLL患者82例.男47例,女35例;年龄39～84岁,平均57岁.节段型31例,连续型40例,混合型11例.手术前后用日本矫形外科学会（JOA）评分判定神经功能;用疼痛视觉模拟评分（VAS）评价颈肩痛程度;用Ishihara法测定颈椎曲率指数（cervical curvature index,CCI）;在MRI上测量脊髓扩大和后移程度.结果 手术平均减压5.2（4～6）个节段.全部病例随访13～58个月,平均41个月.术后JOA评分平均为13.9（11～17）分,较术前[10.9（7～15）分]有显著改善（t=14.65,P＜0.01）,临床效果优良率为98.7%.仅2例出现C5神经根麻痹,为一过性.术后颈肩痛VAS评分平均为1.4（1～3）分,较术前[5.3（4～6）分]明显缓解（t=15.46,P＜0.01）.术后CCI平均为10.5%,较术前（18.8%）下降（t=5.03,P＜0.01）,但未发生颈脊髓再次受压.MRI测量：最狭窄处硬膜囊平均横截面积由85.4 mm2增至153.8 mm2,较术前增加80.1%（t=16.33,P＜0.01）;颈脊髓较术前所在位置平均向后移动6.2mm（t=15.35,P＜0.01）.结论 显露根袖起始部的扩大后壁减压术能使脊髓充分后移,减压彻底,降低脊髓轴位张力,避免C5神经根麻痹,术后无颈椎脱位或半脱位,未出现颈脊髓受压复发情况.

Objective To introduce the surgical strategy of enlarged laminectomy （with partial facet joint dissection to expose the nerve root）, and to discuss its benefit for cervical ossification of the posterior longitudinal ligament（OPLL） with myelopathy. Methods Totally 82 patients with cervical OPLL were treated by enlarged laminectomy from January 1998 to December 2005. There were 47 males and 35 females, with an average age of 57 years （ranged, 39-84 years）. Among them, there were 31 cases of the solitary type, 40 cases of the continuous type, and 11 cases of the mixed type. JOA scoring system and the visual analogue scale （VAS） scoring were applied to evaluate the neurological function and neck/shoulder pain respectively.Ishihara method was employed to measure cervical curvature index（CCI）. The degree of spinal cord backward expanding and displacement were calculated in MR1. Results The mean decompression length was 5.2 （4-6） segments. The mean follow-up duration was 41 months （ranged, 13-58 months）. JOA score has improved from 10.9（7-15） preoperatively to 13.9（11-17） postoperatively （t=14.65, P〈0.01）. The excellent and good rate was 98.7%. The palsy of C5 nerve root occurred in only 2 patients, both recovered after surgery. Zhe mean postoperative VAS score was 1.4（1-3）, comparing with the preoperative score of 5.3 （4-6）. The pain in neck/shoulder was alleviated obviously （t=15.46, P〈0.01 ）. CCI decreased from 18.8% to 10.5%（t=5.03, P〈0.01 ）,but did not follow by neuron function deterioration. MRI indicated that the cross-sectional area at the level of maximum compression of the dural sac increased from 85.4 mm2 preoperatively to 153.8 mm2 postoperatively （t=16.33, P〈0.01）, and the mean spinal cord posterior shift was 6.2 mm （t=15.35, P〈0.01）. Conclusion The enlarged laminectomy is proved to be effective in treating cervical OPLL, in terms of significant posterior shift of the spinal cord, relief of cervical/shoulder pain, lower rate of the palsy of C5 nerve root, with no recurrence of spinal cord compression symptom.