They secrete fluid from the femoral pores at times and I'd imagine that can harden or if they are in conditions that are unsanitary or if there is loose substrate it may cause clogging. There may be other causes beyond that but I'm not sure. Since it's a natural function I would guess that clogging indicates a problem with one of their systems or an external factor.
Mirage came out of brumation on April 26. He was doing great. On May 2 he started acting funny. We just redid his tank, and he keeps going into one of his hides. He just lays there. He shows no intrest in food. HELP!