Abstract

BACKGROUND:Animal models of peripheral partial epiphyseal plate closure are commonly used in related trials.
OBJECTIVE: To modify the original animal models of distal femoral partial epiphyseal plate closure.
DESIGN, TIME AND SETTING: A self-controlled trial was performed at the Experimental Animal Center of General Hospital of Chinese PLA from March to October 2007.
MATERIALS: Twenty healthy New Zealand rabbits of 4-6 weeks old weighing 1.0-1.5 kg were selected.
METHODS: A straight incision about 2 cm was made in lateral knee of 20 rabbits. The subcutaneous tissues and knee capsule were cut open to expose distal femoral condyle. The condylar plate line was clear. Two holes were drilled in the right lateral condyle, about 3.0-4.0 mm deep, and partial normal epiphyseal plate (about 33%-44% of the total growth plate) was removed. An incision deep to periosteum was created in the left side and regarded as self-control.
MAIN OUTCOME MEASURES: Femoral length, valgus angle of the distal femur, and femoral deformity were detected by X-ray photograph, and gross observation. Bone bridge formation of bilateral femora was observed by histological examination.
RESULTS: One rabbit died of diarrhea 31 days after surgery, and 19 were included in final analysis. ①Radiographs showed that the mean length of left femur (control side) was significantly longer but valgus angle was significantly smaller than the right side (experimental side) 4 months after surgery (P < 0.01). The left distal femur averagely grew for 2.27 cm, accounted for 57.6% of the overall femoral growth, and the right side averagely grew for 0.45 cm, accounted for 21.4% of the overall femoral growth. ②Four months after surgery, femoral appearance of the control side was normal, with smooth and complete condylar and facies articularis patellae. While, the experimental side femur was significantly shortened, and severe valgus deformity was observed in the distal femur. ③Five weeks after surgery, layer cells of the epiphyseal plate arranged regularly in the control side. Bone trabecula with many fibers was found in bone defect cavity of the experimental side, and the cell layer of the remnant epiphyseal plate was decreased. The epiphyseal plate was closed in the control side, and bone trabecula of the experimental side was thickened 10 weeks postoperatively.
CONCLUSION: This modeling method is simple, efficient, and easy to manipulate; in addition, the bone bridge area is controllable. The models can meet the study demands for peripheral partial epiphyseal plate closure, and are significant for filling material selection during treatment.

1Department of Emergency, 2Department of Pediatric Surgery, General Hospital of Chinese PLA, Beijing 100853, China

Zhu Zhi-hong☆, Doctor, Attending physician, Department of Emergency, General Hospital of Chinese PLA, Beijing 100853, China
zhihongzhu@
sohu.com

Correspondence to: Xu Rui-jiang, Chief physician, Professor, Department of Pediatric Surgery, General Hospital of Chinese PLA, Beijing 100853, China
xurz@301hospital.
com.cn

Supported by: the National Natural Science Foundation of China, No. 30772276*

Received: 2007-12-24
Accepted: 2008-03-17
(07-50-12-7157/WL)

Zhu ZH, Xu RJ. Establishing a rabbit model of peripheral partial growth plate closure by immediate filling after partial growth plate resection-Zhongguo Zuzhi Gongcheng Yanjiu yu Linchuang Kangfu 2008;12(15):2993- 2996 (China)
[www.zglckf.com/
zglckf/ejournal/
upfiles/08-15/
15k-2993(ps).pdf]

部分骺板挖除后立即充填构建股骨远端周围型骺板部分早闭实验兔模型*☆

摘要
背景：用于骺板部分早闭的实验动物模型多为周围型骺板部分早闭。
目的：在周围型骺板部分早闭模型的基础上，改进建立股骨远端周围型骺板部分早闭动物模型。
设计、时间及地点：自身对照设计实验，于2007-03/10在解放军总医院实验动物中心完成。
材料：健康普通级新西兰幼兔20只，兔龄4~6周，体质量1.0~1.5 kg。
方法：将20只新西兰白兔取膝外侧直切口，长约2 cm，切开皮肤、皮下组织，并于外侧髌旁切开膝关节囊后显露股骨远端外髁，此时股骨远端的骺板线清晰可见。将右侧股骨外髁的骺板挖两个相邻的孔，深度约3.0~4.0 mm，以去除部分正常骺板，面积为股骨远端骺板总面积的33%~44%。左侧仅切开至骨膜作为自身对照。
主要观察指标：术后X射线片测量同时大体观察双侧股骨的长度、股骨远端外翻角度及股骨的畸形情况；组织学检查双侧股骨远端的骨桥形成情况。
结果：1只实验兔术后31 d 因腹泻死亡，19只术后生长良好，进入结果分析。①术后4个月，X射线观察显示左侧股骨平均长度>右侧，外翻角度 < 右侧，两组之间相比，差异显著（P < 0.01）。股骨远端左侧平均生长2.27 cm，占股骨生长的57.6%，右侧平均生长0.45 cm，占股骨生长的21.4%。②术后4个月，对照组股骨形态正常，两髁及髌骨关节面光滑完整。实验侧股骨明显短缩，远端出现严重的外翻畸形。③术后5周，对照组骺板各层细胞排列整齐。实验组骨缺损腔内可见大量纤细的骨小梁，周围剩余骺板细胞层数减少。术后10周，对照组骺板已基本闭合；实验组骨小梁变得更为粗大。
结论：本方法建立的模型操作简单，成功率高，应用灵活，造成的骨桥面积大小可以控制，适用骺板部分早闭疾病动物模型的要求，对治疗过程中充填物的选择亦有一定意义。
关键词：生长面；疾病动物，模型；组织构建

朱志宏1，许瑞江2
解放军总医院，1急诊科，2小儿外科，北京市 100853
朱志宏☆，男，1968年生，北京市人，汉族，2006年解放军军医进修学院毕业，博士，主治医师，主要从事创伤急救及骺板部分早闭的研究。
通讯作者：许瑞江，主任医师，教授，解放军总医院小儿外科，北京市 100853
国家自然科学基金资助项目（30772276）*

中图分类号: R332 文献标识码: A 文章编号: 1673-8225(2008)15-02993-04
朱志宏，许瑞江. 部分骺板挖除后立即充填构建股骨远端周围型骺板部分早闭实验兔模型[J].中国组织工程研究与临床康复,2008,12(15):2993-2996
[www.zglckf.com/zglckf/ejournal/upfiles/08-15/15k-2993(ps).pdf]
(Edited by Lu W/Su LL/Wang L)