It is easy for a snowballed horse to momentarily lose his balance and wrench a fetlock. Half-round shoes do a fair job of shedding snow because of the inside rounded edge. However, half-rounds provide poor winter traction so ice nails or borium should be used with them. Full pads can help prevent snowballing in some situations. Full pads with a convex bubble at the sole seem to be only marginally better than full flat pads at popping out accumulated snow.
Traction is decreased with full pads.
The sole retains it's cupped traction feature, can respire normally, and can descend with weight bearing. As the horse's weight descends on the hoof the pads flex and dislodge the snow that accumulates at the junction of the shoe and sole. Tube pads with open shoes work well in most weather conditions. There are combinations of snow type and temperature where it is impossible to provide safe traction and prevent snowballing. However, in most types of winter footing, good results can be obtained by a combination of the horse's normal shoes with an application of various traction and anti-snowballing devices.