单侧椎板间扩大开窗所获自体骨行腰椎椎间融合的可行性

The feasibility of interbody fusion with local autogenous bone harvested from unilateral interlaminar fenestration in PLIF

目的:观察后路腰椎椎体间融合术(posterior lumbar interbody fusion,PLIF)术中单侧椎板间开窗所获局部颗粒状自体骨的质量和体积,探讨应用该自体骨行腰椎椎间植骨融合的可行性。方法:2011年1月~2012年12月在PLIF术中采用自行设计的椎板间扩大开窗所获骨粒联合单枚cage支撑植骨、椎弓根螺钉系统内固定治疗退变性下腰椎疾病107例。其中男52例,女55例。年龄26~75岁(52.8±9.0岁)。病程6~240个月(69.9±70.7个月)。将单侧椎板间开窗作为一个开窗单位,术中将开窗所获骨制作成直径2~3mm骨粒并测量质量和体积;记录融合椎间隙使用cage高度;术后CT扫描测量手术椎间隙的终板面积、植骨区域面积,计算植骨接触面与终板面积百分比;三维CT判断术后3、6、12、24个月时植骨融合情况;比较术前和术后3、6、12、24个月时JOA评分。结果:107例患者共113个节段进行手术,每个开窗单位可获得2.8~4.4g(3.7±0.3g)、2.6~4.2cm3(3.1±0.3cm3)的颗粒骨。不同年龄、性别、节段和病种间所获骨量无统计学差异(P>0.05)。CT测量终板面积和术中使用cage高度在L4/5和L5/S1椎间隙无统计学差异(P>0.05)。联合单枚cage,椎间植骨区域与终板接触面积可达38%椎间隙填充。达到30%的椎间支撑植骨填充所需骨粒量为3.0g(2.5cm3)。94例患者(98个融合节段)获得24~28个月(24.3±5.9个月)随访,术后24个月时JOA评分总体改善率为65%~100%[(83.5±7.7)%],椎体间植骨融合率为97.9%。未发现内固定松动、断裂和cage沉降。结论:在PLIF术中采用单侧椎板间扩大开窗术式可获得大于2.5cm3的局部自体骨粒,获得的局部自体骨联合单枚cage能够满足椎间融合植骨的骨量要求,从而避免了使用其他植骨材料的相关并发症,节约治疗经费。

Objectives： To quantitatively observe the interbody fusion with local autogenous bone（LAB） harvested from unilateral interlaminar fenestration（UIF） in posterior lumbar interbody fusion（PLIF） and its feasibility. Methods： From January 2011 to December 2012, 107 patients underwent PLIF only using LAB＋one cage and internal fixation with pedicle screw by the fenestration method designed by our team at 1A/5 anti/or LS/S1 of lumbar disc degenerative diseases（DDD）. There were 52 males and 55 females with an average age of 52.8±9.0 years（range, 26-75 years） and with a mean medical history of 69.9±70.7 mouths（range, 6-240 months）. A UIF was looked upon as one fenestration unit. The mass and volume of LAB from UIF were measured by analytical balance and 5ml disposal sterile syringe after LAB was made into the granular of di- ameter of 2-3ram. The heights of cages used intraoperatively were recorded. The area of endplate（Se） and the contact area（Sc） between the cartilaginous endplate and LAB＋cage at every intervertebral space were measured and calculated by PACS of CT workstation after operation. The fusion status was estimated by three dimen- sional CT （3D-CT） and the JOA scores of preoperation and postoperation were compared at 3, 6, 12, 24 months postoperatively. Results： 113 segments of 107 patients were successfully operated. The mass and volume of LAB from UIF showed no significant differences at age, gender, segment and type of DDD（P〉O.05）, and the same result existed about the Se and height of interbody space in IA/5 or L5S1 segments （P〉0.05）. The mean mass and volume of LAB were 3.7±0.3g（range, 2.8-4.4g） and 3.1±0.3cm3（range,2.6-4.2cm3） from UIF. The packing ratio（PR） of intervertebral space with LAB＋one cage was 38%. The volume and mass of LAB of 2.5cm3 and 3.0g were need to reach 30% PR in the operated intervertebral space. 94 cases（98 segments） were followed up for a mean of 24.3±5.9months（range, 24-28 months） postoperatively. The average improvement rate of JOA score was （83.5±7.7）%（range, 65%-100%）, and the fusion rate was 97.9% in the end. No loosening and breakage of instrument and the subsidence of cage were noted. Conclusions： The local autogenous bone harvested from unilateral interlamiar enlarged fenestration is more than 2.5cm3 that can provide enough bone for lumbar interbody fusion combined with one cage in PLIF. The relevant complications of oth- er bone graft substitutes will be avoided and the expense can be saved simultaneously.