Abnormal metaphysis morphology Alternating radiolucent and radiodense metaphyseal lines 2017-05-20T11:32:22Z In cases where this sign arises in children treated with bisphosphonates, the sign is known as the zebra stripe sign, which is radiological manifestation of cyclical bisphosphonate therapy prior to closure of epiphyseal growth plates. Zebra stripe sign Areas of radio-opaque sclerotic bands alternating with those of normal lucency give rise to stripes akin to a zebra.