Are pressure sores serious?

Yes: Yes briefly there are 4 types of stage 1 through stage 4. Stage 1 is relatively superficial with intact skin, where as stage 4 is down to the bone. Once one has gotten one they are much more likely predisposed to having one again.

They can be.: When they get deep, they can become so large that surgery to repair them can become less possible. In this case, wound care and a slow course of healing is the rule.