人工颈椎间盘置换的生物力学系统评价

目的:评价人工颈椎间盘置换对颈椎运动范围及临近节段生物力学的影响.方法:以计算机检索方法检索中国期刊全文数据库中(CNKI:2005/2009)关于人工颈椎间盘置换治疗颈椎病的临床随访、对照实验,检索词为"人工颈椎间盘置换、生物力学".检索后对每项研究的资料结果进行提取、分析.结果:共有21项实验469例颈动脉狭窄患者符合纳入标准,分析结果显示人工颈椎间盘置换后脊髓功能JOA评分较置换前明显升高.置换节段稳定并部分恢复了颈椎正常的活动范围.而且与颈前路减压植骨融合术相比,人工颈椎间盘置换未增加临近节段的关节活动范围和应力负荷,阻止或降低了临近节段的退变及颈椎活动范围减小的发生率,随访时影像学均未见假体移位、脱落、下沉等并发症发生.结论:人工颈椎间盘置换使颈椎运动范围得到一定保持,颈椎稳定性好,置换后对邻近节段影响较小,阻止了相邻节段的退变加速,是颈椎病治疗方面一种具有良好发展前景的治疗方法.但Fh于其临床应用时间短,其潜在的异位骨化、假体下沉、脱出等问题题仍有待于长期临床观察.     

Bryan人工颈椎间盘置换与椎间融合治疗颈椎病的中期疗效比较

背景：国内外有许多相关报道颈人工椎间盘置换治疗颈椎病取得了非常好的近期临床疗效，但因其刚刚开展不久，缺乏长期随访结果。目的：观察Bryan人工颈椎间盘置换治疗颈椎病的临床和影像学结果及邻近节段活动度的情况，并与椎间融合治疗方法比较。设计、时间及地点：回顾性病例分析，于2004—10／2006-04在河北医科大学第三医院脊柱外科完成。对象和方法：22例患者行Bryan假体置换（置换组），同期行常规颈前路椎间盘切除减压植骨融合内固定患者30例（融合组）。在术后1周、3个月、6个月、12个月、24个月进行随访，在每一次随访中拍摄颈椎前屈后伸位、左右侧屈位X射线片，观察置换组假体稳定性及融合组融合节段骨性融合情况。主要观察指标：①材料与宿主的生物相容性。②临床疗效评估。结果：全部病例随访最短24个月，平均30．6个月。①融合组患者术后6个月植骨全部骨性融合；内固定无松动、脱落、断裂的发生。置换组患者置换后无假体移位、脱落等并发症发生。②两组患者随访时神经功能均得到明显恢复，两组JOA评分差异无显著性意义（P〉0．05）。③置换组1例患者随访2年发生椎间自发融合，置换节段活动丢失；其余21例患者置换节段活动度与置换前差异无显著性意义（P〉0．05）。④融合组术后邻近节段的活动度较术前明显增大（P〈0．05）：而置换组置换前后邻近节段活动范围差异无显著性意义（P〉0．05）。结论：与前路融合方法比较，中期随访结果显示Bryan人工颈椎间盘置换治疗颈椎病在取得满意临床疗效的同时能保留置换节段的活动，且避免了置换后上下邻近节段活动度的增加。     

颈椎间盘假体稳定性生物力学评价

目的借鉴腰椎人工椎间盘置换成熟的经验,评价颈椎人工椎间盘置换对失稳颈段脊柱稳定性的重建作用。方法在6具新鲜尸体的颈椎标本上切除C5～6椎间盘,将人工颈椎间盘假体植入该间隙内。对该颈椎节段进行前屈/后伸、左/右侧弯和左/右旋转运动稳定性评价,经颈椎三维运动测量系统测出该节段的运动范围(ROM)。随后施加2Nm,0.6Hz的疲劳载荷共2500次,评定其稳定性,并与标准的C5～6椎间盘破坏后稳定性值相比较。结果正常C5～6前屈、后伸运动范围平均值为17.03°;人工椎间盘植入后前屈、后伸运动范围7.80°,疲劳载荷后前屈、后伸运动范围9.98°;椎间盘破坏后前屈、后伸运动范围25.53°,人工椎间盘植入具有显著的稳定性。正常左右侧弯运动范围平均值为10.75°;人工椎间盘植入后和疲劳载荷后左右侧弯运动范围分别为8.43°和9.43°,椎间盘破坏后左、右侧弯运动范围20.70°。正常左、右旋运动范围平均值为14.82°;人工椎间盘植入后和疲劳载荷后左、右旋运动范围分别为13.38°和13.83°,椎间盘破坏后左右旋运动范围25.88°。结论颈椎间盘破坏后椎节稳定性显著性破坏。人工椎间盘植入后脊柱在前屈、后伸,左右侧弯方向上稳定性显著性改善,左右旋转接近正常值,并可提供59%正常屈伸活动,88%正常左右侧弯活动,93%正常左右旋     

Biomechanical effects of joint line elevation in total knee arthroplasty

Background

Inadequate restoration of the knee joint line after total knee arthroplasty may lead to a poor clinical outcome. The purpose of this study was to quantitatively assess the effects of joint line elevation following total knee arthroplasty with increased joint volume on patellofemoral contact kinematics.

Methods

Six cadaveric specimens were tested. Patellofemoral contact area, contact pressure, and kinematics were measured following total knee arthroplasty with an anatomic joint line and after 4 and 8 mm of joint line elevation, at knee flexion angles of 0°, 30°, 60°, 90° and 120°. Repeated measures analysis of variance with a Tukey post hoc test with a significance level of 0.05 was used for statistical analyses.

Findings

There was a decrease in contact area with joint line elevation at flexion angles of 60°, 90° and 120° (P = 0.009–0.04). There was a significant increase in contact pressure only at 30° of knee flexion with 8 mm of joint line elevation (P = 0.004). Three of the six specimens showed inferior edge loading of the patella component following 8 mm of joint line elevation at 120° of knee flexion. The sagittal plane patellofemoral angle increased significantly with joint line elevation except for 0° knee flexion (P = 0.0002–0.02).

Interpretation

Knee joint line elevation with increased knee volume significantly affects patellofemoral contact area and kinematics and produced inferior edge loading/impingement between the patella and tibial components, this may result in loss of knee range of motion, postoperative pain, and premature component wear.     

颈椎钩突增生的侧位片X线征象

正常颈椎钩突在侧位X线片上呈较为典型的"蚌肉征"~([1]),其骨质增生时侧位片的X线征象鲜见报道~([1]).本文对钩突骨质增生的侧位X线表现进行初步研究.     

全膝人工关节置换涉及的生物力学变化

本文就全膝关节置换(total knee arthroplasty,TKA)技术中不同假体的选择以及手术技术对于术后髌股关节生物力学、髌骨运动轨迹以及假体旋转位置的影响加以分析,探讨影响TKA术后膝关节功能以及假体使用寿命的相关力学因素.传统的解剖标志线受到多种因素的影响缺乏准确性,因此胫骨假体不存在统一的线性定位.股骨上髁轴作为TKA术中确定假体旋转对线的参照轴较为可靠,能获得较为理想的髌股关节生物力学,减少术后并发症.胫骨结节内侧缘至中内1/3线被认为是最理想的胫骨假体旋转定位区间,线性的定位应根据患者膝关节内外翻畸形的程度而定.固定平台和移动平台假体TKA术后都明显的改善了患膝的症状和功能,这两种假体在膝关节评分、疼痛评分、功能评分、髌骨评分及X线片检查结果方面均没有明显差异.但是移动平台假体组TKA术后的最大屈曲度小于固定平台假体组的最大屈曲度.虽然在实验室研究中移动平台型假体在耐磨损和关节运动学方面优于固定平台型假体,但是在临床研究中的观点却并不一致.     

颈椎治疗过程中骨与椎体的生物力学变化

目的:观察颈椎病患者与正常人、颈椎病患者治疗前后影像学和颈周肌群力学指标变化情况,探讨颈椎稳定性在颈椎病发病中的作用,对颈椎病患者非手术疗法的效果以及颈椎病患者的康复结果进行评定.方法:实验于2005-09/2008-11在上海中医药大学附属岳阳中西医结合医院和国家中医药管理局推拿生物力学三级实验室完成.将63例颈椎病患者随机分为推拿组和牵引组,30名正常人做对照组.选取年龄性别与对照组相匹配的颈椎病患者30例,比较两者不稳节段发生率、不稳发生节段部位,以及颈肌力学指标,并观察颈椎病患者采用推拿和牵引治疗2周后的颈椎椎体位移以及颈周肌肌力.结果:①与正常人相比颈椎节段出现不稳病例数及节段数均显著升高.②推拿组患者治疗后颈椎不稳病例数和不稳节段数均显著减少.③颈椎病患者颈伸肌和颈屈肌在60(°)/s等速运动状态下峰值力矩(PT)、F/E显著低于正常人群.④推拿手法治疗后颈椎病患者的峰值力矩、主动肌/拮抗肌比值都有显著的改善.结论:①颈椎稳定性和颈椎周围肌群尤其是颈伸肌肌力变化足颈椎病发生和发展的重要因素.②改善颈椎周围肌群尤其是颈伸肌的肌力是颈椎病手法等非手术治疗方法发生作用的关键环节.     

Motion response of a polycrystalline diamond adaptive axis of rotation cervical total disc arthroplasty

BackgroundCervical fusion is associated with adjacent segment degeneration. Cervical disc arthroplasty is considered an alternative to reduce risk of adjacent segment disease. Kinematics after arthroplasty should closely replicate healthy in vivo kinematics to reduce adjacent segment stresses. The purpose of this study was to assess the kinematics of a polycrystalline diamond cervical disc prosthesis.MethodsNine cadaveric C3–T1 spines were tested intact and after one (C5–C6) and two level (C5–C7) arthroplasty (Triadyme-C, Dymicron Inc., Orem, UT, USA). Kinematics were evaluated in flexion-extension, lateral bending, and axial rotation.FindingsProsthesis placement at C5–C6 and C6–C7 was 0.5 mm anterior and 0.6 mm posterior to midline respectively. C5–C6 flexion-extension motion was 12.8° intact and 10.5° after arthroplasty. C6–C7 flexion-extension motion was 10.0 and 11.4° after arthroplasty.C5–C6 lateral bending reduced from 8.5 to 3.7° after arthroplasty and at C6–C7 from 7.5 to 5.1°. C5–C6 axial rotation decreased from 10.4 to 6.2° after arthroplasty and at C6–C7 from 7.8 to 5.3°.Segmental lordosis increased by 4.2°, and middle disc height by 1.4 mm after arthroplasty. Change in center of rotation from intact to arthroplasty averaged 0.9 mm posteriorly and 0.1 mm caudally at C5–C6, and 1.4 mm posteriorly and 0.3 mm cranially at C6–C7.InterpretationThe cervical disc arthroplasty evaluated restored flexion-extension motion to intact levels and moderately increased segmental stiffness. Disc height increased by up to 1.5 mm and segmental lordosis by 4.2°. The unique prosthesis design allowed the axis of rotation after arthroplasty to closely mimic the native location.     

钩突癌的CT诊断

目的:探讨钩突癌的CT检查和诊断。方法:回顾性分析11例钩突癌的CT检查和诊断资料。结果:CT发现钩突癌的敏感度和特异度分别为100%和81.8%,增强扫描动脉期是诊断的关键,钩突癌CT平扫表现为钩突增大变形,动脉期钩突内可见低密度肿块。结论:CT检查对钩突癌具有重要的诊断价值。     

Biomechanical effects of patellar positioning on intraoperative knee joint gap measurement in total knee arthroplasty

Background

Balancing both the lateral/medial and extension/flexion joint gaps is a prerequisite for soft tissue balance in total knee arthroplasty. The purpose of this study was to quantify the effects of patellar positioning and quadriceps load during total knee arthroplasty on knee joint gap measurements.

Methods

Eight fresh-frozen cadaveric knees ranging in age from 65 to 85 years old were used. Using a medial parapatellar approach, posterior cruciate ligament sacrificing total knee arthroplasty was performed. The specimens were mounted on a custom knee testing system that allowed the femur to be locked in position for knee extension or flexion. Patellar positions of eversion, reduction, and following repair of the arthrotomy were examined. The influence of quadriceps muscle load was investigated by varying the quadriceps load from 0 to 125 N. The lateral and medial joint gaps, represented by the distance from the implanted femoral component surface to the cut tibia surface, were measured with 100 N tibial distraction force using a 3D digitizer in both extension (0°) and flexion (90°).

Findings

Both the medial and lateral joint gaps with patella eversion were significantly smaller than those with patellar reduction and arthrotomy repair (extension: all quadriceps loads, P < 0.0002; flexion: quadriceps loads less than 75 N, P < 0.0002). In patella eversion, quadriceps loading decreased the lateral joint gap more than the medial joint gap in both extension and flexion; however, the effect was greater in knee flexion with significant differences seen at all quadriceps loads, whereas in extension significant differences were only seen for quadriceps loading of 75 N and greater. Patella eversion also caused a lateral-posterior shift and external rotation of the tibia compared to the other conditions (P < 0.005). With patella reduction and repair of the arthrotomy lower quadriceps loading decreased the extension gap significantly more than the flexion gap (P < 0.01). Following repair of the arthrotomy higher quadriceps loading significantly decreased the flexion gap more than the extension gap (P < 0.04).

Interpretation

The patellar positioning and quadriceps muscle loading in total knee arthroplasty have a strong influence on intraoperative joint gap measurements.     

三维图像测量青少年颈椎钩突的形态特征

背景:钩突作为钩椎关节重要组成部分之一,其形态直接影响着颈椎的稳定性和发病率。目的:通过影像学扫描和三维重建分析青少年颈椎钩突的形态特征及发育规律。方法:选择无外伤、无神经症状和体征的6～20岁青少年66名,行多排螺旋CT薄层扫描(0.625～1.25mm),范围C1～T1,将原始数据以DICOM格式导入三维重建软件进行相关指标测量,并按性别、年龄分组进行统计分析。结果与结论:青少年钩突基底长、宽和钩突高、间距从C1～C7均呈递增趋势,且随年龄增长也逐渐递增,但上述所有指标在左右侧别和性别方面差异无显著性意义。钩突倾角在各年龄段中均无明显规律,但变异度较大。表明利用影像资料的三维重建可反映出青少年颈椎钩突随年龄变化的规律及发育特征,为颈椎病的诊断与临床应用提供详实理论依据。     

三维图像测量青少年颈椎钩突的形态特征

背景：钩突作为钩椎关节重要组成部分之一,其形态直接影响着颈椎的稳定性和发病率。目的：通过影像学扫描和三维重建分析青少年颈椎钩突的形态特征及发育规律。方法：选择无外伤、无神经症状和体征的6～20岁青少年66名,行多排螺旋CT薄层扫描（0.625～1.25mm）,范围C1～T1,将原始数据以DICOM格式导入三维重建软件进行相关指标测量,并按性别、年龄分组进行统计分析。结果与结论：青少年钩突基底长、宽和钩突高、间距从C1～C7均呈递增趋势,且随年龄增长也逐渐递增,但上述所有指标在左右侧别和性别方面差异无显著性意义。钩突倾角在各年龄段中均无明显规律,但变异度较大。表明利用影像资料的三维重建可反映出青少年颈椎钩突随年龄变化的规律及发育特征,为颈椎病的诊断与临床应用提供详实理论依据。     

膝关节置换术中膝外翻的生物力学分析

目的:全膝关节置换术中需要解决外侧股骨髁和胫骨平台部分缺损、塌陷;外侧关节囊和韧带挛缩;内侧副韧带松弛等所有这些畸形矫正,恢复膝关节正常的力线和软组织平衡,将假体放在合适的位置,最终获得膝关节的稳定.探讨膝外翻膝关节置换术中力线纠正及关节平衡.方法:应用计算机检索PubMed数据库1991-01/2000-12关于膝关节置换术中膝外翻方面的文章,检索词"TKA,genu valgum",限定文献语言种类为English.对资料进行初审,选取符合研究要求的有关文章找全文.纳入标准:实验研究文章中采用随机、盲法、对照等条件的限制;观察对比研究、经验总结、个案报告等不同文献无限制条件.排除标准:研究目的与本综述目的无关、重复研究的文献.对所得文献进行提炼,共20个研究满足全部纳入标准,予以纳入.结果:在创伤中,胫骨平台骨折常常造成骨折的畸形愈合,骨骺的生长阻滞,最终形成膝关节的外翻畸形.膝外翻全膝关节置换术中髌骨外侧切口得到一部分人的支持,但是还不被普遍接受,有人提出可以通过做关节囊Z形切开或将关节囊前外侧的脂肪垫外移来解决这个问题.建议对严重膝外翻的患者采取外侧入路,以保证外侧软组织的充分松解,矫正膝外翻畸形.全膝关节置换术中,要根据具体情况针对肌腱、韧带作出相应的处理,调整关节伸屈及内外侧都得到良好的关节间隙平衡.对于有严重膝内翻的患者,由于后交叉韧带止点于股骨髁的内上方,后交叉韧带被拉长失去功能,应当选用高匹配的假体.结论:对于膝外翻的患者,如果合理的调整软组织获得良好的关节间隙平衡,就可以采用非限制性假体,不切除交叉韧带,获得膝关节的稳定.     

Update on cervical disc arthroplasty: where are we and where are we going?

Despite the very good results of anterior cervical discectomy and fusion, there are concerns of adjacent level degeneration. For this reason, interest has grown in the potential for motion sparing alternatives. Cervical disc arthroplasty is thus evolving as a potential alternative to fusion. Specific design characteristic and implants will be reviewed and outcomes summarized.     

Biomechanical assessment of unicompartmental knee arthroplasty, total condylar arthroplasty and tibial osteotom

A prospective biomechanical study of unicompartmental arthroplasty using the Oxford Meniscal Knee, total condylar arthroplasty, and tibial osteotomy is described. The 50 patients all had degenerative osteoarthrosis of the knee associated with a varus or valgus deformity. The decision as to which operation a patient would undergo was made on clinical grounds alone; 20 patients underwent unicompartmental arthroplasty, 10 patients total condylar arthroplasty, and 20 patients tibial osteotomy. Dynamic assessments of functional knee joint biomechanics were performed both before and after the surgery. Cadence, velocity and stride length improved in all three groups. Changes in sagittal plane knee parameters were generally small. In the corona) plane, all groups showed correction of varus or valgus deformity, with corresponding decreases in the adduction/ abduction moment. In the unicompartmental group the postoperative corona) plane angulation was predictable from its preoperative value. Some overcorrection of the varus deformity was observed after tibial osteotomy, and the total condylar arthroplasty group showed a small degree of residual deformity.     

牵引对颈椎稳定性影响的生物力学研究

目的：探讨不同牵引重量对颈椎稳定性的影响。方法：采用五具意外伤亡的新鲜尸体颈椎标本（Ｃ１～７）先后制成正常和Ｃ５－６椎间盘部分切除的颈椎生物力学模型,运用生物力学电测技术观察不同牵引重量对颈椎稳定时的总体位移和椎间盘位移的影响。结果：７５Ｎ压缩载荷下,切除组比正常组的压缩载荷－位移增加２７％（Ｐ＜０．０１）,椎间盘膨出位移增加５９％（Ｐ＜０．０１）。牵引下颈椎压缩载荷－位移转向拉伸载荷－位移,其在两组中均随着牵引量的增加而增加。前屈１５度４,６,８ｋｇ牵引下,切除组比正常组的位移分别增加２２％,７％,１７％（Ｐ＜０．０５）,椎间盘位移也呈类似变化。牵引后的二种位移增加幅度以４～６ｋｇ时较适度。结论：椎间盘急慢性损伤后,颈椎稳定性下降,对部分颈椎病患者采用轻度前屈位４～６ｋｇ的牵引方法,符合颈椎的生物力学原理。     

宫颈电圈环切术中颈管黏膜环切预防宫颈柱状上皮外移效果分析

目的探讨宫颈电圈环切除术（LEEP）在治疗上皮内瘤样病变（CIN）时颈管黏膜环切对预防术后宫颈柱状上皮外移的作用。方法 156例CIN患者在行LEEP术前采用抽签方法分为两组,其中对照组78例选择Fisher电极行LEEP锥切;试验组78例在用Fisher电极切除宫颈病变后,再用小环形电极伸入颈管切除颈管黏膜0.5-0.8 cm。术后1、2、3及4周随访阴道流血、分泌物及创面恢复情况,术后3个月随访宫颈柱状上皮外移的发生率及宫颈粘连狭窄的发生率。比较两组手术时间、术中出血量、术后出血时间、术后宫颈柱状上皮外移的发生率及宫颈粘连狭窄的发生率。结果试验组术后4周及术后3个月宫颈柱状上皮外移的发生率分别为6.41%、2.56%,低于对照组24.36%、17.95%,差异有统计学意义（P〈0.05）;两组手术时间、术中出血量、术后出血时间和术后宫颈粘连狭窄发生率的差异均无统计学意义（P〉0.05）。结论 LEEP锥切术中颈管黏膜环切可有效预防术后宫颈柱状上皮外移的发生。