After age 65, minor setbacks like falling and breaking a hip or femur can lead to permanent functional decline in 50% of survivors.

“once you reach a certain age like 65 and if you fall and break your hip or femur um the probability of death is really high I mean it's you know in the order of 15 to 30% what often gets forgotten there even though I try to always mention it is of the survivors meaning the people who don't go on to die within 12 months um 50% of those people never reach the same level of function again so that's an example of why these curves are probably not smooth but in fact um have these discret step offs”