正常髌骨解剖形态学的CT研究

CT study of normal patellar anatomical morphology

目的探讨正常髌骨的解剖形态学特点及其对髌骨置换手术操作与髌骨假体设计的指导作用。方法募集膝关节结构正常的健康成年国人60名，男32名，女28名；年龄18-54岁，平均33．7岁。随机选择左侧或右侧行膝关节伸直位CT扫描，扫描范围从胫骨近端二分之一至股骨远端二分之一。扫描图像应用mimics软件进行三维重建处理，重建后分别生成髌骨的矢状面和横断面图像。按性别分组分别测量及计算髌骨的高度、宽度、厚度，髌骨嵴的位置，高宽比及模拟髌骨置换手术中髌骨切骨后的剩余骨量厚度。结果男性髌骨的高度、宽度、厚度及模拟髌骨切骨后的剩余骨量厚度分别为（31．95±2．77）mm、（45．02±2．70）mm、（22．38±1．63）mm、（13．18±1．62）mm，女性分别为（28．72±2．17）mm、（39．57±2．57）mm、（19．88±1．36）mm、（11．20±1．20）mm，男性与女性之间的差异均有统计学意义。男性髌骨的宽高比为1．42±0．11、髌骨嵴位于髌骨上42．9％偏内侧位置，女性髌骨的宽高比为1．38±0．10、髌骨嵴位于髌骨上42．6％偏内侧位置，男性与女性之间的差异无统计学意义。结论中国人的髌骨相对小、扁且薄，选择及设计髌骨假体时应考虑人种差异。女性的髌骨较男性尺寸更小，在髌骨置换时尤其应该注意保留一定的髌骨厚度。

Objective To investigate normal patellar morphology, then to explore its possible in- structive significance in the design of patella prosthesis for Chinese people and in the process of resurfacing patella. Methods CT scan examinations were performed in 60 normal knees （left or right knee was selected randomly; scan region, from half proximal tibia to half distal femur） of 60 healthy Chinese adults （32 males, 28 females; age range, 18-54 years; mean age, 33.7 years）, then mimics software was used to reconstruct the 3-D morphology of each patella and new coronal and sagittal planes were created. Each patella＇s height, width, thickness, the position of the dome, the ratio of height/width, and the residual thickness after patella was resected at the level of the subchondral bone of the lateral facet during the stimulating process of patella resurfacing were measured or calculated. Results Patella of Chinese male： height 31.95＋2.77 mm, width 45.02＋2.70 mm, thickness 22.38±1.63 ram, the residual thickness after patella was resected 13.18±1.62 ram; Patella of Chinese female： height 28.72±2.17 mm, width 39.57±2.57 mm, thickness 19.88±1.36 mm, the residual thickness after patella was resected 11.20±1.20 mm. Significant differences existed between male and female for all the above four parameters. Patella of Chinese male： the ratio of width/height 1.42±0.11, the position of the dome （medial 42.9%）; Patella of Chinese female： the ratio of width/height 1.38±0.10, the position of the dome （medial 42.6%）. No significant differences existed between male and female for the above two parameters. Conclusion The patella of Chinese people is small, thin and slim, especially in Chi- nese female. These findings should be considered in selecting or designing patella prosthesis to fit the Chi- nese people. For Chinese female, more attention should be paid to keep appropriate residual thickness after the patella was resected during the process of patella resurfacing.