All of the following are seen in rickets except: September 2009
High-Yield Explanation
Ans. A: Frenkels Line In rickets, the skeletal effects are due to lack of calcification of osteoid. The first changes of rickets appear in rapidly growing distal ends of ulna & radius (wrist & knee are commonly involved due to more use). Rarefaction of provisional zone of calcification with widening of epiphysis- diaphysis distance is first to appear. The most obvious change are at 'metaphysis'- where rapid growth is occurring. First change to appear is a 'loss of normal zone of provisional calcification' adjacent to metaphysis. This begins as an indistinctness of the metaphyseal margin, progressing to a 'frayed' appearance with widening of the growth plate, due to lack of calcification of metaphyseal bone. Weight bearing & stress on uncalcified bone gives rise to 'splaying' Sr 'cupping' of metaphysis. A similar but less marked effect occurs in subperiosteal layer, which may cause lack of distinctness of coical margin. Eventually a generalized reduction in bone density is seen. In the epiphysis - there may be some haziness of coical margin. Thus all findings in Rickets occur due to failure of calcification & abnormal demineralization i. Skull changes - Pronounced calvarial demineralization - Basilar Invagination - Indistinct sutural margin - Delayed tooth eruption Premature craniostenosis - Craniotabes - Calvarial thickening following treatment ii. Spine changes - Scoliosis - Biconcave veebral bodies - Triradiatic pelvis.