兔膝关节持续被动活动器的研制与初步应用

目的:为解决实验动物兔术后膝关节早期康复中的持续被动活动(continuous passive mo-tion,CPM)问题,自行研制一种兔膝关节持续被动活动器。方法:根据仿生学原理设计,兔膝关节持续被动活动器主要由支架部分、驱动部分、传动机构和固定部分组成。在23只8月龄雄性新西兰大白兔右侧后肢膝关节切断前交叉韧带后,行自体双股半腱肌移植重建前交叉韧带手术,术后随机分为2组:CPM组与自由活动组。CPM组应用兔膝关节持续被动活动器行早期关节全范围活动康复,每天2次,每次5小时,共6周。不运动时以两片低温热塑板材和尼龙搭扣固定膝关节;自由活动组仅笼内自由活动。观察装置运行情况和兔体重、膝关节肿胀、伤口愈合、关节活动度的变化。结果:整个装置安全可靠,动力足够带动5只兔子同步运动;可以准确、方便地调节膝屈曲角度、运动速度和时间,满足实验要求。CPM组兔子能安静耐受5小时的被动训练,训练期间,未出现坠积性水肿、皮肤破损、压疮、骨折,伤口愈合良好。CPM组术后肿胀程度明显小于自由活动组,且有显著性差异(P<0.01)。2组的体重和关节活动度变化无显著性差异(P>0.01)。结论:兔膝关节持续被动活动器是一种简便可靠、效果较好的术后早期康复器械。

Design and Preliminary Application of Continuous Passive Motion Device for Rehabilitation of Rabbit Knee Joint

Objective In order to meet the continuous passive motion (CPM) requirement in the early phase of rehabilitation of knee joint after rabbit anterior cruciate ligament (ACL) reconstruction, a new CPM device was designed and developed.Methods The device consists of several substructures for supporting, actuating, force conducting and fixing. ACL reconstruction was performed in 23 adolescent male rabbits by using double semitendinosus tendon autograft. The animals were treated postoperatively by either CPM or cage activity. The change in the body weight, swelling, range of motion of knee, tissue oxygen saturation (StO2) in the edge of the wound was observed.Results The CPM device is safe,reliable, and well tolerated by the rabbits, whose general wellbeing is undisturbed. The flexion degrees, speed and time of the CPM device can be exactly adjusted. Skin breakage and other restraint-related complications appeared rarely. There was statistically significant difference in postoperative swelling between CPM and cage activity groups (P<0.01). However, no statistically significant difference in the change of body weight and range of motion(P>0.01).Conclusion The CPM device for rabbit knee joint early rehabilitation is safe, effective and reliable after ACL reconstruction.