Flexion tests are widely used in equine lameness assessment but are controversial due to their subjective interpretation and discomfort to horses. Understanding their appropriate use guides welfare-sensitive veterinary practice.
The flexion test occupies an uncomfortable position in equine welfare: it causes deliberate discomfort as a diagnostic tool, with evidence of both utility and limitation. The welfare justification requires that the discomfort caused leads to diagnoses that improve the horse's long-term welfare — a valid trade-off when performed by skilled veterinarians using standardized, minimal-discomfort protocols. However, the subjective nature of interpretation means that the welfare cost may not be matched by reliable diagnostic gain. Extended or forceful flexion that increases discomfort without improving diagnostic utility is unjustifiable. The movement toward standardized, shorter flexion protocols with clear grading systems represents welfare improvement without compromising legitimate diagnostic value.