Smith G K, Gregor T P, Rhodes W H, Biery D N
Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104-6010.
Am J Vet Res. 1993 Jul;54(7):1021-42.
A 3-year prospective study of large-breed dogs (4 months to 3 years of age) was conducted to evaluate the influence of radiographic positioning and age on coxofemoral joint (hip) laxity, subjective hip score, and development of degenerative joint disease (DJD). The dogs (n = 142) were breeder- or client-owned and represented 14 breeds. With dogs under heavy sedation, hips were radiographed in the standard hip-extended position and in the new compression/distraction position at 4, 6, 12, 24, and 36 months of age. The standard hip-extended radiographic view was evaluated by 3 methods: subjective evaluation by a board-certified veterinary radiologist (WHR), according to the standard 7-point Orthopedic Foundation for Animals (OFA) scoring scheme (OFA/WHR); joint laxity quantitation, using the Norberg angle (NA) method; and subjective scoring by a veterinary orthopedic surgeon for radiographic evidence of DJD. The hips in the distraction radiographic view were evaluated for passive hip laxity, as measured by use of a unitless distraction index (DI). Results of the study indicated that at a specific age (4, 6, 12, 24, or 36 months), all methods of hip evaluation correlated with each other at a moderate level (P < 0.05). The strength of contemporaneous correlation tended to increase with age of evaluation. Longitudinally, the between-method correlations were usually significant (P < 0.05), but not at a sufficiently high level to permit reliable between-method prediction. Prospective intraclass (within-method) statistical analysis of the various hip-scoring methods indicated that DI was superior to NA and OFA/WHR in comparability of score over time. The intraclass correlation coefficient ranged from 0.55 to 0.91 for DI in contrast to 0.40 to 0.78 for NA, and 0.06 to 0.39 for OFA/WHR over the age intervals of the study. For reference, the highest Kappa of 0.39 for the subjective OFA/WHR scoring reflected a maximal level of agreement between time intervals, only slightly better than chance. The associated large error questions the predictive use of the 7-point, subjective hip-scoring scheme, particularly prior to the age of 2 years.
开展了一项针对大型犬（4个月至3岁）的为期3年的前瞻性研究，以评估X线摄影定位和年龄对股髋关节（髋关节）松弛度、主观髋关节评分以及退行性关节病（DJD）发展的影响。这些犬（n = 142）为繁育者或客户所有，代表了14个品种。在深度镇静状态下，于4、6、12、24和36月龄时，对犬的髋关节进行标准髋关节伸展位和新的压缩/牵张位X线摄影。标准髋关节伸展位X线片通过3种方法进行评估：由一名获得委员会认证的兽医放射科医生进行主观评估（WHR），依据动物骨科基金会（OFA）的标准7分评分方案（OFA/WHR）；使用诺伯格角（NA）法进行关节松弛度定量分析；由一名兽医骨科医生对DJD的X线证据进行主观评分。通过使用无量纲牵张指数（DI）测量，对牵张位X线片上的髋关节进行被动髋关节松弛度评估。研究结果表明，在特定年龄（4、6、12、24或36月龄）时，所有髋关节评估方法之间存在中等程度的相关性（P < 0.05）。同期相关性的强度往往随评估年龄的增加而增强。纵向来看，不同方法之间的相关性通常具有显著性（P < 0.05），但程度不足以进行可靠的方法间预测。对各种髋关节评分方法进行的前瞻性组内（方法内）统计分析表明，在评分随时间的可比性方面，DI优于NA和OFA/WHR。在研究的年龄区间内，DI的组内相关系数范围为0.55至0.91，而NA为0.40至0.78，OFA/WHR为0.06至0.39。作为参考，主观OFA/WHR评分的最高Kappa值为0.39，反映了不同时间间隔之间的最大一致性水平，仅略高于随机水平。相关的较大误差对7分主观髋关节评分方案的预测性应用提出了质疑
