2003 Citroen C5 i hear a wierd noise from the front

i have a 2.0 2003 citroen c5 petrol its milleage is 145700 miles and every time i drive it i hear a bump as if its coming from the steering box especilally on bad roads. if its the steering box would it damage anything else if i dont change it.

any help would be appreciated.
thanks.