Wylie C E, Shaw D J, Verheyen K L P, Newton J R
Epidemiology Department, Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, UK Rossdales Equine Hospital, Cotton End Road, Exning, Newmarket, Suffolk, UK.
Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, Midlothian, UK.
Vet Rec. 2016 Apr 23;178(17):420. doi: 10.1136/vr.103588. Epub 2016 Mar 11.
The objective of this cross-sectional study was to compare the prevalence of selected clinical signs in laminitis cases and non-laminitic but lame controls to evaluate their capability to discriminate laminitis from other causes of lameness. Participating veterinary practitioners completed a checklist of laminitis-associated clinical signs identified by literature review. Cases were defined as horses/ponies with veterinary-diagnosed, clinically apparent laminitis; controls were horses/ponies with any lameness other than laminitis. Associations were tested by logistic regression with adjusted odds ratios (ORs) and 95% confidence intervals, with veterinary practice as an a priori fixed effect. Multivariable analysis using graphical classification tree-based statistical models linked laminitis prevalence with specific combinations of clinical signs. Data were collected for 588 cases and 201 controls. Five clinical signs had a difference in prevalence of greater than +50 per cent: 'reluctance to walk' (OR 4.4), 'short, stilted gait at walk' (OR 9.4), 'difficulty turning' (OR 16.9), 'shifting weight' (OR 17.7) and 'increased digital pulse' (OR 13.2) (all P<0.001). 'Bilateral forelimb lameness' was the best discriminator; 92 per cent of animals with this clinical sign had laminitis (OR 40.5, P<0.001). If, in addition, horses/ponies had an 'increased digital pulse', 99 per cent were identified as laminitis. 'Presence of a flat/convex sole' also significantly enhanced clinical diagnosis discrimination (OR 15.5, P<0.001). This is the first epidemiological laminitis study to use decision-tree analysis, providing the first evidence base for evaluating clinical signs to differentially diagnose laminitis from other causes of lameness. Improved evaluation of the clinical signs displayed by laminitic animals examined by first-opinion practitioners will lead to equine welfare improvements.
这项横断面研究的目的是比较蹄叶炎病例与非蹄叶炎但跛行的对照马匹中选定临床体征的患病率，以评估它们区分蹄叶炎与其他跛行原因的能力。参与研究的兽医从业者完成了一份通过文献综述确定的与蹄叶炎相关临床体征的清单。病例定义为经兽医诊断患有临床明显蹄叶炎的马/矮种马；对照为患有除蹄叶炎以外任何跛行的马/矮种马。通过逻辑回归分析检验关联，并计算调整后的优势比（OR）和95%置信区间，将兽医诊所作为先验固定效应。使用基于图形分类树的统计模型进行多变量分析，将蹄叶炎患病率与特定临床体征组合联系起来。收集了588例病例和201例对照的数据。有5种临床体征的患病率差异超过50%：“不愿行走”（OR 4.4）、“行走时短而僵硬的步态”（OR 9.4）、“转弯困难”（OR 16.9）、“体重转移”（OR 17.7）和“蹄部脉搏增强”（OR 13.2）（所有P<0.001）。“双侧前肢跛行”是最佳鉴别指标；有此临床体征的动物中92%患有蹄叶炎（OR 40.5，P<0.001）。此外，如果马/矮种马出现“蹄部脉搏增强”，则99%可被诊断为蹄叶炎。“蹄底扁平/凸起”的存在也显著增强了临床诊断的鉴别能力（OR 15.5，P<0.001）。这是第一项使用决策树分析的蹄叶炎流行病学研究，为评估临床体征以鉴别蹄叶炎与其他跛行原因提供了首个证据基础。提高初诊兽医对蹄叶炎动物所表现临床体征的评估将有助于改善马的福利。
