Abstract

Objectives Dogs with patella alta reportedly have a shorter extensor mechanism than normal dogs. The present study aimed to measure the length of the extensor mechanism and to assess the effect of limb position on the quadriceps muscle length (QML)/femoral bone length (FL) ratio.

Study Design Three-dimensional computed tomography images were taken of 12 Beagle dogs. Each dog underwent computed tomographic imaging 24 times with different limb positions. The QML/FL was measured on each image, along with the hip flexion–extension, hip abduction–adduction and stifle flexion–extension angles. Multiple regression analysis was used to determine the effect of these angles on the QML/FL.

Results The QML/FL was increased with the hip extended (standardized partial regression coefficient 0.855 with linear plotting, 0.829 with log plotting) and with the stifle flexed (standardized partial regression coefficient 0.814 with linear plotting, 0.800 with log plotting). The partial regression coefficient of the hip abduction–adduction angle was small, indicating a small impact on the QML/FL. The 95% confidence range of the QML/FL with the hip extended and stifle flexed was 0.87 to 1.00 (mean ± standard deviation: 0.93 ± 0.03).

Conclusion The QML/FL was more influenced by joint angles when the hip was flexed or the stifle was extended. Hence, these positions should be avoided when evaluating the QML/FL so that the QML is less altered by slight positioning disparities.

Authors' Contributions

Sawako Murakami, Yukari Nagahiro and Masakazu Shimada contributed to study design, acquisition of data and data analysis and interpretation. Nobuo Kanno, Shuji Suzuki, Takuya Yogo and Yasuji Harada contributed to study design, data analysis and interpretation. Yasushi Hara contributed to conception of study, study design and interpretation.

中文翻译：

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肢体位置对正常比格犬股四头肌肌肉长度/股骨长度比的测量的影响。

摘要

目的 据报道，with骨狗的伸肌机制比正常犬短。本研究旨在测量伸肌机制的长度，并评估肢体位置对股四头肌肌长（QML）/股骨长（FL）比的影响。

研究设计 拍摄12头比格犬的三维计算机断层扫描图像。每只狗用不同的肢体位置进行24次计算机断层扫描成像。在每个图像上测量QML / FL以及髋部屈曲-伸展，髋关节外展-内收和st屈-伸展角度。多元回归分析用于确定这些角度对QML / FL的影响。

结果 QML / FL随着髋关节的伸展而增加（线性标绘的标准偏回归系数为0.855，对数标绘为0.829）和膝部屈曲时（线性标绘的标准偏回归系数为0.814，对数标绘为0.800），QML / FL升高。髋关节外展内收角的偏回归系数很小，表明对QML / FL的影响很小。髋关节伸展且st屈屈曲的QML / FL的95％置信范围为0.87至1.00（平均值±标准偏差：0.93±0.03）。

结论 髋关节屈曲或the缩时，关节角度对QML / FL的影响更大。因此，在评估QML / FL时应避免使用这些位置，以免因轻微的定位差异而改变QML。

作者的贡献

村上幸子，长冈由香里和岛田昌一为研究设计，数据采集以及数据分析和解释做出了贡献。no野信夫，铃木修司，Yoya Takuy​​a和原田靖二为研究设计，数据分析和解释做出了贡献。Yasushi Hara为研究，研究设计和解释的概念做出了贡献。