小型犬橈骨皮質與髓質比率之品種差異性研究

Study of different ratio of radial cortex and medulla in toy breeds

謝佳倫(Chia-Lun Hsieh)

指導教授 ： 葉力森

國立臺灣大學/獸醫專業學院/臨床動物醫學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.02520

摘要

橈尺骨骨折在體重小於5公斤的小型犬相當常見，特別是遠端三分之一處，經常因為輕微的創傷即發生骨折。骨骼強度主要由骨質密度與骨骼形態學決定，
骨骼形態學的關鍵又在截面積與皮質骨及髓質骨的比率與分布，長骨主要由皮質骨組成，負責負擔骨骼軸向壓力與支撐體重。

過去已有實驗證實小型犬與中大型犬的皮質髓質骨比率有顯著差異，臨床上又發現小型犬間發生骨折的比率有所不同，玩具貴賓犬與博美犬較為好發，本研究將利用放射線學比較不同品種(包含玩具貴賓犬、馬爾濟斯犬與博美犬)小型犬間皮質髓質骨是否也有明顯的差異性，以及是否有其他形態學上的差異。

實驗材料為調查台灣大學附屬動物醫院從2004年3月至2012年3月所有橈尺骨X光片中，玩具貴賓犬、馬爾濟斯犬與博美犬橈骨皮質髓質比率、橈骨截面積、饒骨長度、皮質骨厚度等數質加以計算，實驗結果顯示玩具貴賓犬與博美犬犬的皮質髓質骨比例較為相似，且同時與馬爾濟斯犬的皮質髓質骨比率有顯著差異性，另外也發現玩具貴賓犬橈骨較長，博美犬橈骨較細、形狀較扁等特徵。這些結果顯示，玩具貴賓犬與博美犬的橈骨截面積、轉動慣量、橈骨截面形狀及皮質骨厚度可能就是造成其橈骨骨折機率比馬爾濟斯犬高的原因。

關鍵字

小型犬 ； 橈骨 ； 形態學 ； 骨折

並列摘要

Distal radial/ulnar fracture is a common orthopedic condition in toy breed dogs, which can be developed even after a short fall. The strength of bone is from its mineral deposit and geometrical parameters. The latter includes cross-sectional area (CSA), cross-sectional moments of inertia (Ip), mean cortical thickness, and cortical thicknesses. These factors all affect the mechanical behavior of bones. Toy Poodle, Maltese and Pomeranian are popular toy breed dogs in Taiwan. However, distal radial fractures were more common in Toy Poodles and Pomeranians. In previous studies, the ratio of cortex and medulla of radius is different between large, medium and toy breed dogs. However, geometrical differences of radius among different toy breed dogs have never been studied. The aim of the present study is to compare different parameters in these breeds of dogs. Radial/ulnar radiographic images of toy breed dogs collected from imaging database of the National Taiwan University Veterinary Hospital from March 2004 to March 2012 were used. Through ANOVA statistical analysis, significant differences were noted in bone length, bone diameter, and cortex/medulla ratio among different breeds. The results suggest that some morphological properties of the radius of toy Poodles and Pomeranians, namely cross-sectional area, cross-sectional moments of inertia, cross-sectional shape and cortical thicknesses, may contribute to their higher fracture rate than the Maltese dogs.

並列關鍵字

toy breeds ； geometrical parameter ； radius ； fracture

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