下肢伸直襁褓体位对股骨近端发育影响的实验研究

目的利用新生大鼠模拟婴儿下肢伸直襁褓体位建立动物模型，探讨该体位对股骨近端发育的影响。方法用医用胶带将45只新生Wistar大鼠幼鼠（雌性24只，雄性21只）双下肢、髋关节缠绕固定10d，模拟婴儿生后双下肢伸直襁褓体位，作为实验组；另选45只新生幼鼠（雌性24只，雄性21只）双下肢不予处置，作为对照组。于第10天随机处死实验组、对照组幼鼠各16只，常规制备石蜡切片，番红O-固绿染色观察组织形态。余下幼鼠继续喂养8周后，通过大体标本及X线摄片，观察股骨近端变化。结果实验组股骨近端组织切片染色发现股骨头变小，前倾角变大，大量结缔组织增生，细胞形态、数量、排列明显异常。大体外观及X线摄片见实验组股骨头外观不规则、表面不光滑，股骨颈变短、增粗，股骨颈周围软组织增生，前倾角变大（P〈0．05），股骨颈干角减小，大粗隆肥大，股圆韧带增粗变长，髋臼指数较对照组明显增大（P〈0．05）；实验组髋关节脱位率（49／50）明显高于对照组（P〈0．01）。结论本实验成功制作了大鼠下肢伸直襁褓体位的动物模型，该体位可干扰股骨近端发育．甚至导致髋关节脱位。

The empirical study of the developmental influence of proximal femoral arisen from the posture of straight-leg swaddle.

Objective Through establishing a model of newborn rat＇s posture of straight-leg swaddle, this study observed the developmental influence of proximal femoral arisen from this posture. Methods The hip joints and lower limbs of 45 Wistar rats （24 male and 21 female） were fixed to extending position with ad- hesive tape for 10 days （experiment group） , the other 45 newborn rats （24 male and 21 female） without treat- ment on legs and hips were used as the control group. On day 10th, the 16 newborn rats from both experimental group and control group were randomly killed, followed by performing the paraffin sections using the routine method and subsequently observing the histomorphology by Safranin O/fast green staining. The remaining rats continue to be fed for 8 weeks, and were killed, the assessment of dysplastic proximal femoral were done by the gross morphology and x-ray photography. Result The histological section of proximal femora from experimental group show that the morphological, number and arrangement of the cells were apparently abnormal; and their femoral head became irregular and unsmooth; collum femoris became tubbiness, surrounded by more soft tis- sue, the anteverted angle of femoral neck of dislocated hip was greater than that of the normal hip （ P 〈 0. 05 ） ; greater trochanter became accrescent, femoral neck shaft angle grow down, ligamentum teres femoris was hyper- plastic and hypertrophia; the acetabular index has significant difference between the experimental group and the control group （P 〈 0.05） ; The hip dislocation rate （49/50） of experimental group was obviously higher than that of the control group （ P 〈 0.01 ）. Conclusion The model of newborn rat＇ s posture of straight-leg swaddle was established successfully, and showed that this posture was easy to result in proximal femoral dysplasia, even leading to dislocation of hid joint.