CAJ | 학술논문

目的通过生物力学实验的方法研究当延长颈椎前路融合节段数时对邻近节段的活动度、小关节应力的影响,探讨导致融合术后邻近节段退变的原因.方法利用6具成人新鲜尸体颈椎标本(C2～T1),模拟颈椎前路椎间盘切除、钢板螺钉内固定、椎间融合术.每具标本依次进行C4～s单节段融合、C4～6双节段融合、C4～7三节段融合,利用特制颈椎三维运动测试系统模拟人体前屈、后伸、左右侧屈和左右旋转运动,使用混合测试方法,测量并记录此时标本整体活动度、上位邻近节段活动度及小关节内压力、下位邻近节段活动度变化.结果当依次进行单节段融合、双节段融合、三节段融合后,标本整体活动度呈递减趋势,差异有统计学意义(P＜0.05).上位邻近节段C3～4随融合节段的延长活动度逐渐升高,呈递增趋势,在前屈、后伸、侧屈运动中有显著统计学差异(P＜0.05).C3～4小关节内平均压力和峰值压力的测量发现单节段组、双节段组、三节段组于后伸和侧屈运动中较完整组升高,比较有显著统计学差异(P＜0.05).结论当颈椎前路融合的节段数延长,会导致上位邻近节段活动度以及小关节内压力逐渐增加,可能因此而加速邻近节段退变.
목적 통과생물역학실험적방법연구당연장경추전로융합절단수시대린근절단적활동도、소관절응력적영향,탐토도치융합술후린근절단퇴변적원인.방법 이용6구성인신선시체경추표본(C2～T1),모의경추전로추간반절제、강판라정내고정、추간융합술.매구표본의차진행C4～s단절단융합、C4～6쌍절단융합、C4～7삼절단융합,이용특제경추삼유운동측시계통모의인체전굴、후신、좌우측굴화좌우선전운동,사용혼합측시방법,측량병기록차시표본정체활동도、상위린근절단활동도급소관절내압력、하위린근절단활동도변화.결과 당의차진행단절단융합、쌍절단융합、삼절단융합후,표본정체활동도정체감추세,차이유통계학의의(P＜0.05).상위린근절단C3～4수융합절단적연장활동도축점승고,정체증추세,재전굴、후신、측굴운동중유현저통계학차이(P＜0.05).C3～4소관절내평균압력화봉치압력적측량발현단절단조、쌍절단조、삼절단조우후신화측굴운동중교완정조승고,비교유현저통계학차이(P＜0.05).결론 당경추전로융합적절단수연장,회도치상위린근절단활동도이급소관절내압력축점증가,가능인차이가속린근절단퇴변.
Objective To study the effect of length of cervical anterior fusion on adjacent levels by Biomechanical test.Methods Six fresh-frozen human cervical specimens were used in this study.The specimens were tested in flexion,extension,bending and rotation on a spine 3D test system.The specimens were tested intact and then underwent a single-level anterior cervical discectomy and fusion (ACDF) at the C4-5 first,a double-level fusion at the C4-5,and finally extended to triple-level at the C4-7,Based on a hybrid test method.Changes in overall range of motion (ROM),segmental motion and facet joints pressure during flexion,extension,bending and rotation were measured and statistically analyzed.Results The overall ROM of the entire spinal construct decreased progressively as the single-level fixation extending to 2-level and 3-level (P ＜ 0.05).A progressive increase in ROM above (C3-4) the fused motion segment units (MSUs) was found during flexion,extension and bending (P ＜ 0.05).In bending and extension,a same result was recorded on the average pressure and max pressure of Cs-4 facet joints (P ＜ 0.05).Conclusions This study has demonstrated that the biomechanics at adjacent levels to a cervical spine fusion are altered and that there was progressively increased adjacent segment motion and stress as a single-level ACDF extended to a 3-level fusion,which might lead to the acceleration of adjacent segment degeneration.