It can be a symptom but is more generally a lymphatic issue where they are stood in but its just worth checking for pulses anyway. If you havnt got digital pulses then there is nothing major, it should go down with exercise. I brought mine off the grass for a few days on soaked hay to establish if the grass was the cause. I'm not hugely concerned about the puffiness with mine, more the digital pulses as they shouldn't be quite so prominent! Clivers is a good supplement to give for lymphatics.