Maybe someone with more medical knowledge than the rest of us can indicate whether a guy of 100 years old can still arise.
Speaking of which - my first gross out post of the day - I once overheard a conversation from two young women one of whom was discussing the work done by her mum (a carer). The carer and her workmate had visited a 92 year old man who, when they arrived, was clearly involved in pleasuring himself. The carers main concern being that they only got around 15 mins for that visit and their dilemma being how long they'd have to wait for a result and whether they had time to properly wash him afterwards. Dunno how the whole thing ended because the park and ride bus reached my stop before the lassie got to the end of the story.