Measurements of femoral angles, femur length, and hip width in cat radiographs

ABSTRACT Femoral angle, femur length, and hip width were measured in radiographs of 92 intact domestic cats, males and females of mixed breed from the Center for Zoonosis Control of the Federal District. The animals showed no trauma, orthopedic diseases or angular deformities and had closed physeal lines. Accordingly, we measured aLPFA (anatomical lateral proximal femoral angle, aLDFA (anatomical lateral distal femoral angle), mLPFA (mechanical lateral proximal femoral angle), mLDFA (mechanical lateral distal femoral angle), IA (femoral inclination angle), FL (femur length) and HW (hip width) using ventrodorsal radiographs, with both hindlimbs in a single exposure to an X-ray beam centered on the hip. The mean values of the variables were: mLPFA: 82.5±3.62°; aLPFA: 80.1±4.29°; mLDFA: 96.1±3.51° (males) and 97.3±2.05° (females); aLDFA: 94,3±3.43°; IA: 136.6±3.86°; FL: 12.9±0.55cm (males) and 13.4±0.66cm (females); and HW: 3.1cm±0.23 (males) and 3.5±0.26cm (females). These values will serve as a reference for the diagnosis of angular deformities and as support for planning corrective osteotomies in domestic cats.

摘要 本研究对来自联邦区人畜共患病控制中心（Center for Zoonosis Control of the Federal District）的92只健康混种家猫（雌雄不限）的X光片开展参数测量。受试动物均无创伤、骨科疾病或成角畸形，且骺线已闭合。研究采用双后肢同一次曝光的腹背位X光片，以髋关节为中心的X线束完成拍摄，依次测量了解剖学外侧股骨近端角（anatomical lateral proximal femoral angle, aLPFA）、解剖学外侧股骨远端角（anatomical lateral distal femoral angle, aLDFA）、力学外侧股骨近端角（mechanical lateral proximal femoral angle, mLPFA）、力学外侧股骨远端角（mechanical lateral distal femoral angle, mLDFA）、股骨倾斜角（femoral inclination angle, IA）、股骨长度（femur length, FL）及髋宽（hip width, HW）。各参数均值如下：mLPFA为82.5±3.62°；aLPFA为80.1±4.29°；mLDFA雄性组为96.1±3.51°，雌性组为97.3±2.05°；aLDFA为94.3±3.43°；IA为136.6±3.86°；FL雄性组为12.9±0.55cm，雌性组为13.4±0.66cm；HW雄性组为3.1±0.23cm，雌性组为3.5±0.26cm。上述测量值可作为家猫成角畸形诊断的参考依据，并为家猫矫正截骨术的术前规划提供支持。