Table 1_Trimming of nails in healthy dogs does not change gait parameters when comparing pre- and post-nail trim.docx

Claw length in dogs is widely assumed to influence gait, with the belief that excessively long claws may alter locomotion patterns and lead to musculoskeletal issues. Still today, this hypothesis lacks objective data. This is the first study to investigate the potential impact of claw length on canine gait using validated pressure-sensing treadmill analysis in a small cohort of clinically healthy dogs, both before and after claw trimming. Contrary to common assumptions, no significant differences in gait parameters, such as stride length, stance phase duration, or vertical ground reaction forces, were observed before and after claw trimming. Length of the front paws was 2 mm longer before nail trimming (p = 0.022), and the medio-lateral center of pressure movement was slightly decreased by 1% of paw width before nail trimming (p = 0.018). The observed absence of differences in temporospatial and kinetic parameters suggests that, although local paw-level mechanics such as medio-lateral COP or paw length may be affected by claw length, these alterations do not translate into functional changes in global gait parameters. This supports the conclusion that, in clinically sound dogs, longer claws do not impair overall locomotor function. These findings suggest that long claws may not be the cause of altered gait, but rather a consequence of decreased natural abrasion due to abnormal or inefficient gait. This insight shifts the focus from claw length as a primary problem to underlying biomechanical issues that may hinder normal claw abrasion. Further studies are needed to explore the relationship between gait quality and claw health.

犬类爪甲长度常被推测可影响步态，学界普遍认为过长爪甲可能改变运动模式，进而引发肌肉骨骼疾患。时至今日，该假说仍缺乏客观数据支撑。本研究为首次采用经过验证的压力感应跑步机分析（pressure-sensing treadmill analysis）技术，针对小型临床健康犬队列在爪甲修剪前后的状态，探究爪甲长度对犬类步态的潜在影响。与普遍认知相悖的是，爪甲修剪前后，犬类的步态参数（如步幅、支撑相时长、垂直地面反作用力）均未出现显著差异。修剪爪甲前，犬只前爪长度较修剪后长2毫米（p=0.022）；且修剪前的内外侧压力中心（medio-lateral center of pressure）位移量较修剪后小幅降低，约为爪宽的1%（p=0.018）。本研究中时空参数与动力学参数未出现显著差异的结果表明，尽管爪甲长度可能影响爪部局部力学特性（如内外侧压力中心（COP）或爪长），但此类改变并不会反映为整体步态参数的功能性变化。这一结果佐证了如下结论：在临床健康犬只中，较长的爪甲并不会损害整体运动功能。上述研究结果提示，过长爪甲或许并非步态异常的诱因，反而可能是因步态异常或运动效率低下导致自然磨损减少的结果。该认知将研究重点从“爪长为核心问题”，转向了可能阻碍爪甲正常磨损的潜在生物力学异常。未来仍需开展更多研究，以探究步态质量与爪甲健康之间的关联。