I was given this report:At L4 - L5: there is a posterior osteocartilagenous bar with hypertrophic changes involving the facets. This results in mild compression of the sac and possible compression of the L5 nerve roots as they exit the sac. There is no encroachment on the foramina.At L3-L4 there is very mild disc space narrowing.I'm just not completely sure what these words all mean. Can someone help transcribe this to a layman's terms please? thanks in advance.