I know a few ridgebacks; nice dogs, shame about the ridge being like spina bifida in humans.
What you are talking about is this
wiki said:Dermoid sinus
Dermoid sinus is a congenital neural-tube defect that is known to affect this breed. The dermoid is often likened to a thin "spaghetti noodle" beneath the skin. Puppies should always be screened at birth by the breeder and veterinarian & the examination repeated as the puppies grow before they go to their new homes. This is done by palpation of the subcutaneous dorsal midline from the base of the skull to the insertion of the tail. Surgical removal is an option for affected neonates, puppies and adult dogs. All affected dogs, even those surgically corrected, should be desexed and never be bred from. But, surgical dermoid sinus removal can be extremely cost prohibitive and because all unremoved dermoid sinuses will eventually abscess, and abscessed dermoid sinuses will cause the dog a painful death, dermoid puppies should be culled whenever surgical correction is not an option. However, it has been shown that supplementation of folic acid to the diet of the brood bitch before mating & during pregnancy reduces the incidence of dermoid sinus.
Which is likened to Spina Bifita in humans, the ridge is not linked to that, it is just a health defect which is genetic.
KaHn