Wrist-guards prevent such injury with a plastic splint held on the inside of the wrist.
The splint curves inwards towards the palm at the wrist joint, where it is exposed, and is concealed and held in place by padding at the hand and arm.
Because the force of the fall has to impact upon some part of the body, wrist guards increase the chance of facial or head injuries because the arms cannot support the upper body on impact.
Additionally, if the fingers are held in a loose fist upon impact or are folded towards the palm they can catch on the ground during a fall, causing severe grazing to the knuckles.
If the fall is particularly steep, because the wrist guard ends just below the base of the fingers, the first set of knuckles is at risk of injury by being bent back over the wrist-guard.