摘要
目的:验证自行设计的颈部挥鞭伤仿真发生装置的可操作性及稳定性,通过模拟实验分析颈部挥鞭伤的伤情特点以及损伤程度和牵引加速度之间的关系。方法:实验于2003-09/2004-05在第三军医大学新建的实车碰撞实验室完成。选取健康成年杂种犬21只,随机分为4组:重度伤组、中度伤组、轻度伤组各6只,分别施加(40±1.5)g,(25±1.5)g,(15±1.5)g的牵引加速度;对照组3只,用于检查正常颈段脊髓的病理切片。采用自行设计的颈部挥鞭伤仿真发生装置,建立犬颈部挥鞭伤的实验模型,通过联合行为评分(分为五级:0级:弛缓性瘫痪;1级:肌紧张和膀胱控制失调;2级:受伤后肢的负重作用;3级:表现为1或2个后肢跛行;4级:能短时间行走、跑,不能走直行路线;5级:正常,完全恢复)对实验犬的运动、感觉、反射以及肢体动作协调等脊髓功能进行综合评定。检测伤前和伤后皮质体感诱发电位和运动诱发电位的变化以及损伤程度。结果:实验纳入21只犬全部进入结果分析,中途无脱落。①颈部挥鞭伤仿真发生装置的建立:此装置可以根据落锤重量和下落高度差的调节产生比较稳定、不同大小的牵引力和牵引加速度,能较好的模拟汽车追尾碰撞中乘员的头颈部运动特点,可用于仿真汽车追尾碰撞过程中颈部挥鞭伤的发生过程。②行为学观测(联合行为评分):不同的加速度组其损伤的程度不同。重度伤组、中度伤组和轻度伤组在致伤后各时相点的评分均小于正常值(5分),且3组评分依次递增。③皮质体感诱发电位的变化:伤后即刻重度伤组出现了波形基本消失,没有明显的NPN波形。与各自伤前比较,中度伤组和轻度伤组伤后即刻的N1,P1波均明显升高[(37.2±2.7),(12.4±1.3)μV;(58.9±3.1),(48.6±2.0)μV;(18.2±2.1),(12.4±2.0)μV;(55.5±2.0),(48.7±2.3)μV,P均<0.01]。与重度伤组伤后24h比较,中度伤组和轻度伤组的N1,P1波均明显降低[(21.4±1.4),(17.9±1.9),(17.0±2.5)μV,P均<0.01;(53.9±4.8),(51.7±4.4),(51.5±8.4)μV,P均>0.05]。④运动诱发电位的变化:伤后即刻重度伤组出现了波形基本消失,没有明显的NPN波形。与各自伤前比较,中度伤组和轻度伤组伤后即刻的N1,P1波均明显升高[(20.5±2.5),(7.7±0.8)μV;(25.85±1.4),(17.8±2.6)μV;(12.1±1.9),(7.85±1.3)μV;(22.6±1.7),(17.6±2.0)μV,P均<0.01]。与重度伤组伤后24h比较,中度伤组和轻度伤组的N1,P1波均明显降低[(18.5±2.5),(13.1±3.9),(8.75±0.7)μV,P均<0.01;(21.7±2.4),(19.7±1.8),(19.8±2.3)μV,P均<0.05]。⑤脊髓C4～7段病变情况:大体观察除了重度伤组出现颈部皮下出血,肺部出血水肿外,其余组皆无异常。光镜检测下重度伤组可见神经元数量较少,绝大多数发生变性、坏死,中度伤组可见大部分的神经元变性,轻度伤组形态基本正常。结论:自制的颈部挥鞭伤致伤装置能较好地模拟汽车追尾碰撞中乘员的头颈部运动特点,可用于仿真汽车追尾碰撞过程中颈部挥鞭伤的发生过程。对犬施加的致伤牵引加速度越大,则引起犬的颈段脊髓损伤程度也越严重。
AIM： To demonstrate the maneuverability and stability of a self-designed emulation equipment for cervical whiplash injury, analyze the characteristics of whiplash injury by means of simulative experiment, and investigate the relationship between degree of injury and drawing acceleration. METHODS： The experiment was accomplished in the new-built crash laboratory of Third Military Medical University from September 2003 to May 2004. Twenty-one healthy and grown dogs were randomly divided into four groups： grievous injury（n=6）, moderate injury（n=6）, mild injury（n=6） and control groups（n=3）. The drawing acceleration was （40±1.5） g, （25±1.5） g and （15±1.5） g in grievous injury, moderate injury and mild injury groups respectively. The dogs of control group were used to examine the pathological section of natural cervical spinal cord. A self-designed emulation equipment for cervical whiplash injury was used to build a dog model of cervical whiplash injury. The function of spinal cord was measured synthetically such as activity, sense, reflection and coordination of limb action by using combined behavioral score（CBS, five grades： grade 0, flaccid paralysis; grade 1, muscular tension and bladder disturbance; grade 2, weight-loading of the injured hind limbs, grade 3, claudication in 1 or 2 hind limbs; grade 4： being able to walking and jumping in a short time but unable to walk straight; grade 5： normal and complete recovery）. The changes of cortical somatosensory evoked potential （CSEP）, motor evoked potential （MEP） and degree of injury were evaluated before injury and after injury. RESULTS： All the 21 dogs were analyzed in the result without loss. ① The establishment of emulation equipment for whiplash injury： Steady and adjustable drawing force and acceleration were generated through adjusting the drop hammer downcast difference in height and weight. It simulated the characteristics of head-neck movement of occupants in the rear-end collision of automobiles, and could emulate the occurrence of whiplash injury during rear-end collision. ②Observation of behaviors （CBS）： The degree of injury was different in the four groups. The CBS marks of grievous injury, moderate injury and mild injury groups were increased by degrees and were all under normal value.③The changes of CSEP： It was shown by CSEP that waveform nearly disappeared and no obvious NPN waveform was in grievous injury group immediately after injury. N1 and P1 waves in moderate injury and mild injury groups were significantly increased immediately after injury as compared with before injury[（37.2±2.7） μV vs （12.4±1.3）μV, （58.9±3.1）μV vs （48.6±2.0）μV in the former group, （18.2±2.1）μV vs （12.4±2.0）μV, （55.5±2.0）μV vs （48.7±2.3）μV in the latter group, all P 〈 0.01]. As compared with the grievous injury group, the N1 and P1 waves were significantly decreased in the moderate injury and mild injury groups at 24 hours after injury[（21.4±1.4）μV vs （17.9±1.9）, （17.0±2.5）μV, both P〈 0.01 for N1; （53.9±4.8）μV vs （51.7：t-4.4）, （51.5±8.4）μV, both P 〉 0.05 for PI]. ④Changes of MEP： It was shown by MEP that waveform nearly disappeared and no obvious NPN waveform was in grievous injury group immediately after injury. N1 and P1 waves in moderate injury and mild injury groups were significantly increased immediately after injury as compared with before injury[（20.5±2.5）μV vs（7.7±0.8）μV, （25.85±1.4）μV vs （17.8±2.6）μV in the former group, （12.1±1.9）μV vs （7.85±1.3）μV, （22.6±1.7）μV vs （17.6±2.0）μV in the latter group, all P 〈 0.01]. As compared with the grievous injury group, the N1 and P1 were significantly decreased in the moderate injury and mild injury groups at 24 hours after injury[（18.5±2.5）μV vs （13.1±3.9）, （8.75±0.7）μV, both P 〈 0.01 for N1; （21.7±2.4）μV vs （19.7±1.8）, （19.8±2.3）μV, both P 〉 0.05 for P1].⑤Diseases of C4 to C7 in spinal cord： Gross examination showed that subcutaneous hemorrhage of cervical part and lung edema appeared in the dogs of grievous injury group, while there was no abnormity in other groups. Shown by light microscopy, the number of nerve cells in grievous injury group was less than other groups, and most of nerve cells were degenerative and necrotic. In moderate injury group, most of nerve cells were degenerative, and in mild injury group, the form of most nerve cells was natural. CONCLUSION： The self-designed equipment for cervical whiplash injury could well simulate the movement condition of occupants＇head and neck in the rear-end collision of automobiles, and can emulate the occurrence of whiplash injury during rear-end collision. It is suggested that the more the drawing acceleration is, the more serious the pathological degree of cervical spinal cord injury in dogs was.
出处
《中国临床康复》
CSCD
北大核心
2005年第30期122-124,i0004,共4页
Chinese Journal of Clinical Rehabilitation
基金
GM中国科学研究基金项目(30122202)~~
