fusion of the fifth lumbar vertebra to the first segment of the sacrum on only one side.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
The abnormal development of one half of the fifth lumbar vertebra so that it is fused with the sacrum.See: sacralization
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