Translation: No one knows which hip-bone will see the light of day
Usage: We cannot foresee our fate. Usually when people get old, they develop waist problems. Hence, if we are to die according to age, then we might expect the oldest to die first, meaning those with the worse hip problems or those who suffer most. Yet, life is not like that; old people die and young people die. No one can predict which hip would outlive the other. You cannot foretell who would die first. This is similar to another proverb which says 'fresh leaves fall and old (or dead) leaves fall too'.
No. 610 in Bu me Bε by Peggy Appiah et al.___________________
Caveat: text in red is my own translation and understanding of the proverb.