The relationship between sagittal hoof conformation and hindlimb lameness in the horse

SummaryBackgroundLameness can be multifactorial and may result from the accumulation of multiple seemingly unrelated causes. The identification of factors associated with lameness could be one method to decrease incidence of lameness and prolong the equine athlete's competitive life.ObjectivesTo determine if there is an association between hoof balance in the sagittal plane and hindlimb lameness.Study designCase‐control study.MethodsEighty client‐owned horses with hindlimb lameness (cases) and 80 horses with no detectable hindlimb lameness (controls) were prospectively enroled following lameness evaluation as either cases (lameness localised with regional anaesthesia) or controls (no hindlimb lameness). Lameness cases were divided based on location (stifle, tarsus, proximal metatarsus and other sites). Lateromedial radiographs were performed on hind hooves and plantar angle of the distal phalanx (PADP) was determined. The prevalence of negative/neutralPADPand medianPADPs were calculated. Conditional logistic regression and Wilcoxon signed rank tests were used to analysePADPs, and odds ratios were calculated. Significance was set at P<0.05.ResultsThe meanPADPwas significantly smaller in cases compared to controls. The meanPADPwas significantly smaller in horses with lameness localised to tarsus and proximal suspensory, but not the stifle. Lameness in horses was associated with a negative/neutralPADP(Odds ratio [OR] 3.87, 95% confidence interval [95%CI] 1.97–7.61, P<0.01), with lameness localised to the tarsus (OR4.98, 95%CI1.34–18.54, P = 0.01) and proximal suspensory (OR5.16, 95%CI1.11–23.89, P = 0.03) being associated with a negative/neutralPADP.Main limitationsIt is unknown whether the negative/neutralPADPcontributed to lameness or lameness resulted in lowerPADP.ConclusionsHorses with hindlimb lameness localised to the distal tarsus and proximal metatarsus, but not the stifle, were more likely to have negative/neutralPADPs. Corrective farriery to improvePADPmay be investigated further as one component in the treatment of hindlimb lameness localised to regions proximal to the foot.The Summary is available in Portuguese – see Supporting Information