Perkins N R, Reid S W J, Morris R S
EpiCentre, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
N Z Vet J. 2005 Jun;53(3):171-83. doi: 10.1080/00480169.2005.36502.
To investigate risk factors for injury to musculoskeletal structures of the lower fore- and hind-limbs of Thoroughbred horses training and racing in New Zealand.
A case-control study analysed by logistic regression was used to compare explanatory variables for musculoskeletal injuries (MSI) in racehorses. The first dataset, termed the Training dataset, involved 459 first-occurrence cases of lower-limb MSI in horses in training, and the second, the Starting dataset, comprised a subset of those horses that had started in at least one trial or race in the training preparation that ended with MSI (n=294). All training preparations for horses that did not suffer from MSI for which complete data were available were used in the analyses as controls, and provided 2,181 and 1,639 preparations for the Training and Starting datasets, respectively. Multivariate logistic regression was used to evaluate risk factors, and results were reported as odds ratios (OR) and 95% confidence intervals (CI).
Horses aged > or =5 years were at higher risk of injury than 2-year-olds. Elevated odds of MSI occurred in horses in the Starting dataset that were training in the 1997-1998 year compared with the 1999-2000 year, and in those horses where trials comprised >20% of all starts in a preparation. Training preparations that ended in winter, and horses in their third or later training preparation, had lower odds of MSI compared with those ending in other seasons or the first preparation, respectively. Reduced odds of MSI were observed in preparations in which starts occurred compared with those that had no starts, and in the Starting dataset, preparations that included more than one start had a reduced likelihood of MSI compared with preparations that had only one start. In the Training dataset, preparations longer than 20 weeks were associated with reduced odds of MSI compared with those shorter than 20 weeks. Cumulative racing distance in the last 30 days of a training preparation was best modelled with linear and quadratic terms. Results indicated that increasing cumulative racing distances were associated with an initial reduction in the odds of MSI that then levelled out and finally appeared to increase again as the explanatory variable continued to increase. The risk of MSI varied significantly between trainers.
This study identified intrinsic (age) and extrinsic risk factors for MSI in training and racing Thoroughbreds in New Zealand. The risk of MSI initially decreased, then increased, as cumulative racing distance increased. Significant variation between trainers indicated management and training methods influence the risk of MSI.
调查在新西兰进行训练和比赛的纯种马前、后肢肌肉骨骼结构损伤的风险因素。
采用逻辑回归分析的病例对照研究，比较赛马肌肉骨骼损伤（MSI）的解释变量。第一个数据集称为训练数据集，包含459例训练中马匹首次出现的下肢MSI病例，第二个数据集称为起跑数据集，由那些在以MSI结束的训练准备中至少参加过一次试跑或比赛的马匹子集组成（n = 294）。所有未患MSI且有完整数据的马匹训练准备情况均用作对照，训练数据集和起跑数据集分别提供了2181例和1639例训练准备情况。采用多变量逻辑回归评估风险因素，结果以比值比（OR）和95%置信区间（CI）表示。
年龄≥5岁的马匹比2岁的马匹受伤风险更高。与1999 - 2000年相比，1997 - 1998年进行训练的起跑数据集中的马匹发生MSI的几率升高，且在那些试跑占所有起跑20%以上的马匹中也是如此。与在其他季节结束或首次训练准备相比，在冬季结束的训练准备以及第三次或后续训练准备中的马匹发生MSI的几率较低。与没有起跑的训练准备相比，有起跑的训练准备中观察到MSI几率降低，并且在起跑数据集中，与只有一次起跑的训练准备相比，包含多次起跑的训练准备发生MSI的可能性降低。在训练数据集中，与短于20周的训练准备相比，长于20周的训练准备与MSI几率降低相关。训练准备最后30天的累积比赛距离最好用线性和二次项进行建模。结果表明，随着累积比赛距离增加，MSI几率最初降低，然后趋于平稳，最后随着解释变量继续增加似乎再次升高。不同训练师之间MSI风险差异显著。
本研究确定了新西兰纯种马训练和比赛中MSI的内在（年龄）和外在风险因素。随着累积比赛距离增加，MSI风险最初降低，然后升高。训练师之间的显著差异表明管理和训练方法会影响MSI风险。
