Topping-off手术治疗腰椎退行性疾病的影像学分析

目的:评价Topping-off手术治疗连续双节段腰椎退行性疾病的影像学改变。方法 :2008年8月~2012年12月,35例连续双节段腰椎退行性椎管狭窄症(其中上位病变节段为轻或中度退变)患者在我院接受手术治疗。其中男23例,女12例,年龄62.6±18.9岁(30~79岁)。所有患者均接受腰椎单节段融合(PLIF)+上位节段棘突间动态稳定(置入Coflex)手术(Topping-off手术),其中L4/5置入Coflex+L5/S1融合14例,L3/4置入Coflex+L4/5融合21例。回顾性分析患者术前及末次随访时X线片上Coflex置入节段及其上位相邻节段的椎间隙高度、椎间活动度、椎体偏移、椎间隙角及腰椎前凸角;在MRI上对Coflex置入节段和其上位相邻节段椎间盘退变情况进行改良Pfirrmann分级。结果:患者均安全完成手术,手术时间为112±21min(95~155min),出血量为403±111ml(300~520ml)。均未出现硬脊膜破裂、神经损伤等相关并发症。随访24.8±12.8个月(11~65个月)。术后末次随访时Coflex置入节段及其上位相邻节段椎间隙前缘高度、椎间隙后缘高度与术前比较均无统计学意义(P0.05);Coflex置入节段椎间隙角较术前显著性增大(t=-1.8,P0.05);Coflex上位相邻节段椎间隙活动度(过伸位角度-过屈位角度)、椎间隙角及腰椎前凸角与术前比较均无统计学意义(P0.05)。24例随访2年以上患者MRI检查显示Coflex置入节段及其上位相邻节段椎间盘的改良Pfirrmann分级情况与术前相同。结论:Topping-off手术可以保持Coflex置入节段良好的稳定性,并保留该节段部分运动功能及其上位相邻节段节段正常活动,减少了上位相邻节段退变发生的危险因素。     

后方韧带复合体对腰椎椎间融合术后早期相邻节段退变的影响

目的探讨后方韧带复合体对腰椎椎间融合术后早期相邻节段退变的影响。方法 2000年1月至2010年1月在我科实施后路腰椎减压椎间融合内固定治疗L4~5椎间盘突出患者60例。A组(30例)行保留后方韧带复合体的腰椎椎间融合术(posterior lumbar interbody fusion,PLIF),B组(30例)行切除后方韧带复合体的PLIF术。比较两组手术前、后日本骨科协会(Japanese orthopaedic association,JOA)评分及改善率。术前、末次随访时测量腰椎X线片上L3~4椎间盘的高度和椎间隙动态角度、L3~4椎体滑移距离并进行比较。术前及末次随访时对L3~4椎间盘进行Pfirrmann分级。结果手术前、后两组患者的JOA评分差异有统计学意义(P0.05),术后两组JOA评分差异均无统计学意义(P0.05),两组之间改善率差异无统计学意义(P0.05)。A组9例患者出现了L3~4节段的邻近节段退变(adjacent segment disease,ASD),B组17例出现了L3~4节段的ASD。其中A、B两组均有2例患者为有症状的ASD。术前两组患者X线片上L3~4椎间盘的高度、椎间隙动态角度、L3~4椎体滑移距离相比差异均无统计学意义(P0.05),而末次随访时差异有统计学意义(P0.05)。A组末次随访时Pfirrmann分级1级6例,2级22例,3级2例,无4、5级病例。B组末次随访时Pfirrmann分级1级4例,2级24例,3级2例,无4、5级病例。结论腰椎椎间融合术中保留后方韧带复合体可减少术后早期相邻节段退变的发生。     

腰椎Activ L人工椎间盘置换术后影像学表现与临床疗效的相关性分析

目的:探讨腰椎Activ L人工椎间盘置换术后的影像学表现与临床疗效的相关性。方法:2009年3月~2012年3月,应用Activ L假体对32例腰椎间盘退变性疾患的患者进行人工椎间盘置换术,其中30例患者共36个假体获得12~46个月(平均28.8个月)的随访,随访2年以上者20例(其中随访3年以上15例)。均在术前和末次随访时进行腰、腿痛VAS评分和Oswestry功能障碍指数(ODI)评分,同时测量手术节段和上、下相邻节段的活动度、椎间隙高度及腰椎前凸角。对术前及末次随访时的VAS评分、ODI评分,手术节段和上下相邻节段的活动度、椎间隙高度以及腰椎前凸角分别进行配对t检验,分别以每例患者末次随访时的VAS评分和ODI评分为应变量,以末次随访时的活动度、椎间隙高度以及腰椎前凸角为自变量,进行相关性分析。结果:末次随访时的腰痛VAS评分、腿痛VAS评分和ODI评分与术前比较均有显著改善(P0.0001)。末次随访时,手术节段、上位相邻节段活动度明显增加(P0.05),而下位相邻节段活动度无明显变化(P0.05);手术节段及其上、下相邻节段椎间隙高度与术前比较均无明显变化(P0.05);腰椎前凸角与术前比较无明显变化(P0.05)。末次随访时,手术节段、上下相邻节段的活动度和椎间隙高度及腰椎前凸角与VAS评分和ODI评分均无明显相关性(r0.2138,P0.05)。结论:腰椎Activ L人工椎间盘置换术治疗腰椎间盘退变性疾患的近中期疗效满意,近中期随访时手术节段、上下位相邻节段的活动度和椎间隙高度与临床疗效无明显相关性。     

颈前路减压零切迹椎间融合器与传统钛板固定融合术后相邻节段退变的比较

目的 :比较颈前路减压零切迹椎间融合器(Zero-P)与传统钛板内固定融合术治疗单/双节段脊髓型颈椎病对术后相邻节段退变的影响。方法:回顾性分析2015年1月～2018年3月采用颈前路减压Zero-P与传统钛板内固定融合术治疗的113例脊髓型颈椎病患者的资料,其中Zero-P组(A组)65例,传统钛板组(B组)48例,A组再分为单节段组(n=44)和双节段组(n=21),B组再分为单节段组(n=28)和双节段组(n=20),4组患者年龄、性别构成比、手术节段均无统计学差异(P0.05)。比较两种术式的手术时间、术中出血量,以及4组的术前、末次随访时的日本骨科协会(Japanese Orthopaedie Association,JOA)评分、疼痛视觉模拟评分(visual analog scale,VAS),末次随访时评估患者术后是否出现吞咽困难,并在颈椎侧位X线片上测量术前、术后即刻、末次随访时相邻节段椎间隙高度,评估术前、末次随访时的相邻椎体骨化情况,在颈椎MRI上应用椎间盘Pfirrmann分级评估术前、末次随访时的相邻节段椎间盘退变情况。结果:单节段A组随访时间为18.0±7.9个月,单节段B组为15.8±8.8个月,双节段A组为14.8±6.4个月,双节段B组为15.8±8.2个月,4组间无统计学差异(P0.05)。A组手术时间较B组明显缩短(P0.05),术中出血量两组无明显差异(P0.05)。4组患者末次随访时的JOA评分、VAS评分较术前均有明显改善(P0.05),同节段A、B组间比较JOA评分改善率无明显差异(P0.05),术前、末次随访时同节段A、B组间比较VAS评分无明显差异(P0.05)。双节段B组末次随访时上、下相邻椎间隙高度较术前、术后均有明显下降(P0.05),其余3组末次随访时上、下相邻椎间隙高度较术前、术后均无明显差异(P0.05)。末次随访时,双节段B组上、下相邻椎间隙高度显著低于双节段A组(P0.05),单节段A、B组末次随访时上、下相邻椎间隙高度无明显差异(P0.05)。末次随访时,相邻椎体骨化发生率单节段B组(32.14%)与单节段A组(6.82%)比较、双节段B组(40%)与双节段A组(9.52%)比较更高(P0.05)。根据Pfirrmann分级,双节段B组(30%)比双节段A组(4.76%)更容易发生相邻节段椎间盘退变(P0.05),单节段A、B组末次随访时相邻节段椎间盘退变无明显差异(P0.05);B组中双节段(30%)比单节段(7.14%)更容易发生相邻节段椎间盘退变(P0.05),A组中单、双节段末次随访时相邻节段椎间盘退变无明显差异(P0.05)。B组的术后吞咽困难发生率均比A组高(P0.05)。结论:颈前路单/双节段减压内固定融合手术治疗脊髓型颈椎病中,使用Zero-P与传统钛板内固定融合相比,临床疗效无明显差异,但Zero-P可减少术后相邻节段退变,且在双节段比较中优势更明显。     

Denis B型胸腰椎爆裂性骨折行后路单节段钛网重建术对邻近节段的影响

目的探讨Denis B型胸腰椎爆裂性骨折行后路单节段钛网重建术对邻近节段的影响。方法 20例Denis B型胸腰椎爆裂性骨折患者行后路单侧椎体次全切除、脊髓270°减压、钛网植骨重建前中柱及椎弓根钉内固定并后路重建术。1年后取出钉棒内固定并继续随访1～3年。末次随访通过动力位X线片、MRI评估邻近节段椎间盘变化情况。结果末次随访时,患者钛网均无松动。有2例患者出现不同程度塌陷,Cobb角有所丢失。所有患者远端椎间盘有不同程度退变,椎间隙未见明显变窄,邻近节段椎间盘退变Pfirrmann分级:Ⅰ级退变13例,Ⅱ级退变5例,Ⅲ级退变1例,Ⅳ级退变1例。结论后路单节段固定钛网重建治疗Denis B型胸腰椎爆裂性骨折加速邻近节段椎间盘退行性变。     

退行性腰椎滑脱固定融合术相邻节段椎间孔变化

[目的]探讨退行性腰椎滑脱固定融合术相邻节段椎间孔变化。[方法]回顾性分析2015年7月～2018年7月在本院行单节段腰椎后路椎间融合术治疗L4/5单节段轻度退行性腰椎滑脱84例的影像资料。评价腰椎复位与融合情况,并对手术节段的上位相邻节段双侧椎间孔的椎间孔高度、宽度和面积进行测量和比较。[结果] PLIF术后完全复位48例,复位程度100%;部分复位36例,复位程度平均为(47.12±12.84)%。随访时间6～36月,平均(12.07±8.70)月。末次随访时,腰椎CT显示椎体间融合率100.00%,未发现椎间融合器沉降、移位,无严重术后并发症需二次手术者。术前、术后1周和末次随访时上位相邻节段的椎间孔高度、宽度和面积,左右两侧间差异均无统计学意义(P>0.05)。术后1周,上位相邻节段双侧椎间孔高度、宽度和面积均较术前显著增加,差异均有统计学意义(P<0.05);末次随访时,上位相邻节段双侧椎间孔高度、宽度和面积均较术后1周时减少,但差异均无统计学意义(P>0.05)。L4/5节段的节段前凸角由术前的(14.01±7.20)°增加至术后的(17.77±8.32)°,差异有统计学意义(P<0.05)。[结论]腰后路椎间融合器置入,恢复椎间隙高度可以恢复节段前凸角,增大手术节段上位相邻节段的椎间孔孔径及面积。     

退变性腰椎滑脱融合术后邻近节段椎间盘退变的远期观察

目的 观察退变性腰椎滑脱融合术后邻近节段椎间盘的远期退变情况.方法 分析62例退变性腰椎滑脱患者融合术后5～9年的影像学资料,其中单节段融合37例,多节段融合25例,根据Pfirrmann系统对融合的邻近节段椎间盘进行退变分级,对单节段和多节段融合的邻近节段、融合的近侧和远侧节段椎间盘退变情况及JOA评分进行比较和统计学分析.结果 融合的近侧和远侧节段椎间盘退变分级差异有统计学意义(P<0.05),近侧比远侧节段退变更明显;多节段和单节段融合术后邻近节段椎间盘退变分级差异有统计学意义(P<0.05),多节段比单节段更严重.末次随访时,单节段融合组的JOA评分显著高于多节段融合组(P<0.05).结论 退变性腰椎滑脱融合术可引起邻近节段椎间盘退变,最好选择单节段和远侧节段融合,尽量避免多节段和近侧节段融合.     

Dynesys非融合术后腰椎节段放射学改变及椎间盘再水化

[目的]分析Dynesys动态固定术后腰椎节段的放射学变化和残留椎间盘的再水化现象。[方法]回顾性分析2011年12月~2013年10月在本院接受Dynesys动态固定的38例腰椎间盘退行性疾病患者资料,记录患者术前,术后10 d,末次随访时VAS、ODI评分,采用腰椎X线片测量椎间隙前后缘高度、腰椎前凸角及屈伸活动度(range of motion,ROM),利用腰椎MRI计算手术节段椎间盘平均标准椎间盘信号(calibrated disc signal,CDS)。[结果]38例患者术后平均随访(25.11±6.96)个月。末次随访时,患者腰腿痛VAS评分和ODI指数较手术前后明显改善(P0.05)。手术节段椎间隙前、后缘高度较手术前后均明显降低(P0.05)。上位邻近节段椎间隙前缘高度与术前比较差异无统计学意义(P=0.47),后缘高度较手术前均显著下降(P0.05),平均丢失(10.34±9.81)%。下位邻近节段椎间隙前后缘高度及腰椎前凸角均无显著变化。手术节段屈伸ROM比术前明显减少(P0.05),但仍保留术前ROM的64.11%;相邻节段及腰椎整体ROM较术前差异无统计学意义。23例患者接受腰椎MRI复查,平均CDS由术前(42.74±13.15)%改善至(47.69±14.38)%,差异有统计学意义(P=0.004)。[结论]Dynesys非融合术后残留椎间盘出现再水化,表明其可能具有促进退变椎间盘修复的作用。该系统保留了固定节段一定ROM,不引起邻近节段过度活动。但是术后存在手术节段椎间隙高度丢失以及上位邻近节段代偿性前凸等问题。     

Isobar TTL系统治疗腰椎退行性疾病的中长期随访结果

[目的]探讨Isobar TTL内固定系统治疗腰椎退行性疾病的中长期疗效。[方法]回顾性分析因腰椎退行性疾病采用Isobar TTL内固定系统治疗并有2年以上随访的20例患者资料。男11例,女9例;平均年龄43.8岁(26~61岁)。临床疗效采用疼痛视觉模拟评分(visual analog scale,VAS)和Oswestry功能障碍指数(Oswestry disability index,ODI)进行评估。在X线片上分析动态固定节段及其上相邻节段的椎间隙高度、椎间活动度及腰椎前凸角,采用UCLA(University of California at Los Angeles Grading Scale,UCLA)系统评估椎间盘退变情况。在MRI上采用改良Pfirrmmann分级系统评估椎间盘退变情况。[结果]平均随访时间为51.9个月(26~87个月)。所有患者末次随访时VAS评分和ODI评分均较术前明显改善(P<0.05),未出现因邻近节段退变性疾病而需要手术的患者。末次随访时动态固定节段的椎间隙高度及椎间活动度较术前减少,差异有统计学意义(P<0.05),而椎间盘UCLA评分与术前比较差异无统计学意义(P>0.05)。上相邻节段的椎间隙高度、椎间活动度、椎间盘UCLA评分及腰椎前凸角与术前比较差异均无统计学意义(P>0.05)。16例患者末次随访时接受腰椎MRI检查,结果提示动态固定节段及上相邻节段的椎间盘改良Pfirrmmann分级与术前比较差异均无统计学意义(P>0.05),但其中2例出现邻近节段退变加重。3.2%(4/124)的螺钉出现松动,无内固定断裂、感染等并发症。[结论]Isobar TTL内固定系统治疗腰椎退行性疾病的临床疗效满意,但不能避免动态固定节段出现退变加重。     

退变性腰椎不稳固定节段与邻近节段椎间盘退变的关系

目的探讨后路减压、固定、融合术后治疗退变性腰椎不稳的疗效,固定后邻近节段椎间盘退变发生机率与相关性。方法回顾性分析2005年8月～2010年8月下腰椎固定术180例患者的临床资料。结果随访1～5年,其中有症状性退变2例,均为固定近端相邻的椎间盘,而且此阶段椎间盘术前均有不同程度的退变。结论退变性腰椎不稳固定治疗后出现邻近节段椎间盘退变与腰椎固定及固定阶段多少本身无关,与固定前邻近节段椎间盘有无退变关系明显,且多发生于固定节段近端。     

腰椎内固定融合术后邻近节段退变的影响因素

目的探讨腰椎内固定融合术后邻近节段退变的影响因素。方法对1998年3月至2002年5月33例行腰椎内固定融合术的病例进行随访研究,观察其术后邻近节段退变的发生率、发生年龄、部位、影像学特点以及临床表现,对是否“悬浮固定”、内固定融合范围、不同邻近节段退变的风险进行对比。结果33例患者随访34～82个月,平均4年7个月。发现影像学上有退变表现10例（占30．3％）,10例中有9例退变发生在头侧节段。发生邻近节段退变以60岁以上患者为主。是否进行“悬浮固定”对内固定融合术后邻近节段退变的影响无统计学差异。多节段融合术后较单节段融合术后邻近节段退变有增多的趋势。L2／L3作为邻近节段时退变风险较高,而L5／L1,作为邻近节段退变风险较低。结论头侧邻近节段较尾侧节段更容易发生退变。如果L2／L3可能作为邻近节段,术前有退变表现,术中需将其进行固定融合,而如果L5／S1在术前没有明显退变证据,则不需要将其进行固定融合。腰椎内固定融合时,尽量避免长节段固定融合。     

Dynamische Versorgung der Lendenwirbels?ule

Total disc replacement and posterior dynamic stabilization represent alternatives to lumbar spinal fusion which should reduce the risk of adjacent segment degeneration. Disc replacement is indicated for pure discopathy without facet joint degeneration. Spinopelvic balance influences the implant's biomechanics. Therefore pelvic incidence, sacral slope, segmental lordosis and the mean axis of rotation need to be considered. Dynamic stabilization is indicated in moderate discopathy and facet joint degeneration, in degenerative spondylolisthesis grade I with a hypermobile segment and in dynamic lumbar stenosis. The combination of caudal fusion and cranial dynamic stabilization allows a better maintenance of lordosis with multiple level instrumentation and prevents adjacent segment degeneration. If pelvic incidence and sacral slope are high, L5-S1 should be fused because of elevated shear forces.     

Anschlusssegmentbeweglichkeit nach monosegmentaler Bandscheibenprothesenimplantation und monosegmentaler Fusion Segment L4/5

Background

Preservation of movement at the treated segment and possible reduction of adjacent segment effects is assumed to be an advantage of non-fusion technologies over fusion. The aim of this study was to compare the segmental range of motion (ROM) at the operative level, the cranial and caudal adjacent levels and the global lumbar spine ROM (L2-S1) after monosegmental fusion and total disc replacement (TDR).

Patients and methods

Radiographic data was collected from 27 patients with level 1 degenerative disc disease operated at level L4/5. The ROM was assessed at the index level (L4/5), the cranial and caudal adjacent level and for the lumbar spine (L2-S1).

Results

In the TDR group no significant changes of lumbar spine ROM (L2–S1) and segmental ROM (index level, cranial and caudal adjacent level) were noticed. In the fusion group there was a significant reduction of lumbar ROM (L2-S1) and index level ROM. Additionally the relative ROM in the adjacent caudal segment significantly increased while no changes were seen in the cranial segment.

Conclusion

The relative ROM was significantly increased in monosegmental fusion at level L4/5 compared to TDR. To what extent this fact may result in early adjacent segment degeneration in cases of fusion compared to TDR is still unknown.     

Correlation between sagittal plane changes and adjacent segment degeneration following lumbar spine fusion

Adjacent segment degeneration following lumbar spine fusion remains a widely acknowledged problem, but there is insufficient knowledge regarding the factors that contribute to its occurrence. The aim of this study is to analyse the relationship between abnormal sagittal plane configuration of the lumbar spine and the development of adjacent segment degeneration. Eighty-three consecutive patients who underwent lumbar fusion for degenerative disc disease were reviewed retrospectively. Patients with spondylolytic spondylolisthesis and degenerative scoliosis were not included in this study. Mean follow-up period was 5 years. Results were analysed to determine the association between abnormal sagittal configuration and post operative adjacent segment degeneration. Thirty-one out of 83 patients (36.1%) showed radiographic evidence of adjacent segment degeneration. Patients with normal C7 plumb line and normal sacral inclination in the immediate post operative radiographs had the lowest incidence of adjacent level change compared with patients who had abnormality in one or both of these parameters. The difference was statistically significant (P<0.02). There was no statistically significant difference in the incidence of adjacent level degeneration between male and female patients; between posterior fusion alone and combined posterolateral and posterior interbody fusions; and between fusions extending down to the sacrum and fusions stopping short of the sacrum. It was concluded was that normality of sacral inclination is an important parameter for minimizing the incidence of adjacent level degeneration. Retrolisthesis was the most common type of adjacent segment change. Patients with post operative sagittal plane abnormalities should preferably be followed-up for at least 5 years to detect adjacent level changes.     

Does anterior lumbar interbody fusion promote adjacent degeneration in degenerative disc disease? A finite element study

Background  

The increase in the number of anterior lumbar interbody fusions being performed carries with it the potential for the long-term complication of adjacent segmental degeneration. While its exact mechanism remains uncertain, adjacent segment degeneration has become much more widespread. Using a nonlinear, three-dimensional finite element model to analyze and compare the biomechanical influence of anterior lumbar interbody fusion and lumbar disc degeneration on the superior adjacent intervertebral disc, we attempt to determine if anterior lumbar interbody fusion aggravates adjacent segment degeneration.     

腰椎融合术后邻近节段退变的诊断与治疗

目的：探讨腰椎融合术后邻近节段退变的特点及再手术治疗的术式与疗效.方法：回顾性分析2002年1月至2004年12月间收治的10例因腰椎管狭窄症或腰椎滑脱症曾行后路减压、植骨及椎弓根内固定术,术后12～132个月（平均41.6个月）出现新的腰腿痛症状的病例.对所有患者进行影像学检查,与术前资料比较,并行手术治疗.结果：X线片显示融合的上方（1个节段7例,2个节段1例）或下方（1个节段2例）邻近节段出现了退变,首次术前及术后上述邻近节段均未见退变征象.8例MRI显示邻近节段出现了新的椎管狭窄,且有明显的神经压迫.采用后路术式,将减压及固定融合范围向邻近退变节段延伸.经7～36个月平均12.1个月的随访,优良率80%.结论：腰椎融合术后邻近节段退变是术后症状复发的原因之一,应仔细鉴别症状复发的原因.对于有明显神经压迫者,再手术治疗仍可取得较好的疗效.     

Adjacent segment degeneration in the lumbar spine

BACKGROUND: A primary concern after posterior lumbar spine arthrodesis is the potential for adjacent segment degeneration cephalad or caudad to the fusion segment. There is controversy regarding the subsequent degeneration of adjacent segments, and we are aware of no long-term studies that have analyzed both cephalad and caudad degeneration following posterior arthrodesis. A retrospective investigation was performed to determine the rates of degeneration and survival of the motion segments adjacent to the site of a posterior lumbar fusion. METHODS: Two hundred and fifteen patients who had undergone posterior lumbar arthrodesis were included in this study. The study group included 126 female patients and eighty-nine male patients. The average duration of follow-up was 6.7 years. Radiographs were analyzed with regard to arthritic degeneration at the adjacent levels both preoperatively and at the time of the last follow-up visit. Disc spaces were graded on a 4-point arthritic degeneration scale. Correlation analysis was used to determine the contribution of independent variables to the rate of degeneration. Survivorship analysis was performed to describe the degeneration of the adjacent motion segments. RESULTS: Fifty-nine (27.4%) of the 215 patients had evidence of degeneration at the adjacent levels and elected to have an additional decompression (fifteen patients) or arthrodesis (forty-four patients). Kaplan-Meier analysis predicted a disease-free survival rate of 83.5% (95% confidence interval, 77.5% to 89.5%) at five years and of 63.9% (95% confidence interval, 54.0% to 73.8%) at ten years after the index operation. Although there was a trend toward progression of the arthritic grade at the adjacent disc levels, there was no significant correlation, with the numbers available, between the preoperative arthritic grade and the need for additional surgery. CONCLUSIONS: The rate of symptomatic degeneration at an adjacent segment warranting either decompression or arthrodesis was predicted to be 16.5% at five years and 36.1% at ten years. There appeared to be no correlation with the length of fusion or the preoperative arthritic degeneration of the adjacent segment.     

腰椎融合辅以邻近节段动态固定治疗腰椎退行性疾病的早期临床疗效观察

目的 评价腰椎融合辅以邻近节段K-Rod动态固定治疗腰椎退行性疾病的临床疗效及对腰椎运动功能的影响,探讨K-Rod动态固定对邻近节段保护的优劣.方法 回顾性分析2010年4月~2011年9月采用椎间融合辅以邻近节段K-Rod 动态固定及单节段椎间植骨融合内固定术的51例患者.A组（K-Rod组）24例患者术前邻近节段存在退变,行单节段融合辅以邻近节段K-Rod动态固定;B组（单节段融合组）27例患者术前邻近节段无不稳或退变,行单节段椎间植骨融合内固定术.对比评价2组腰腿痛视觉模拟量表（visual analogue scale,VAS）评分、Oswestry 功能障碍指数（ Oswestry disability Index,ODI） 、椎间隙高度、腰椎总活动度（range of motion,ROM）及头侧邻近第一节段活动度（ROM1）、头侧邻近第二节段或尾侧第一邻近节段活动度（ROM2）、保护节段及邻近节段退变（adjacent segment degeneration,ASD）发生率.结果随访 24~37个月.2组患者术后VAS评分及ODI均显著改善,且2组间差异无统计学意义.2组间腰椎总ROM术前及末次随访之间均无差异.A组保护节段末次随访时椎间隙高度与术前无差异.2组ROM1及ROM2术前术后相比差异均有显著统计学意义,2组间相比差异无统计学意义.A组末次随访时8例患者出现11（11/138,8%）枚螺钉松动;B组无螺钉松动.结论 腰椎融合辅以邻近节段动态固定具有较好的临床疗效,增加的动态固定保护了术前已存在退变的节段,避免了多节段融合,降低了单节段融合邻椎病的风险,因此适应证选择合适,具有较好的临床应用价值.     

Adjacent segment degeneration after lumbar spinal posterolateral fusion with instrumentation in elderly patients

This retrospective study investigated adjacent segments radiologically and clinically after posterolateral fusion of the lumbar spine with instrumentation. Thirty-two patients over 60 years old with a postoperative follow-up of at least 4 years were included. These patients all met the criteria of a postoperative symptom-free period of over 2 years, evident fusion mass seen on plain radiographs, and no implant breakage or loosening. There was 81.3% excellent and good clinical results (26/32). For all patients, flexion and extension views of the lumbar spine were done preoperatively and postoperatively. Adjacent segments below the fusion, above the fusion, and cranial to the above adjacent segment were examined. Three patients each with translation > 4 mm in adjacent segments were found in both the short and long (> or = 3 segments) fusion groups. The incidence was 16.7% (3/18) in the short fusion group and 21.4% (3/14) in the long fusion group. However, no statistically significant difference (p = 0.7878) was found according to the Fisher exact test. Comparing the effect of different types of instruments, there still was no statistically significant difference (p = 0.1161) between the VSP plate and Isola rod groups in inducing degeneration of adjacent segments after posterolateral fusion of the lumbar spine. After measuring the mobility of degenerated adjacent segments, relative hypermobility was more likely responsible for the accelerated degeneration rather than the absolute increase of mobility.