has part has part characteristic of inheres in has modifier Abnormal sacrum morphology Dysplastic sacrum HP:0008455 A developmental defect of the sacrum characterized by partial or disordered development of the sacrum in which portions of the sacrum, which normally is formed by fusion of five sacral vertebrae S1-S5, fail to form or fail to form normally. Sacral dysgenesis Absence of some of the sacral and coccygeal bones Partial sacral agenesis UMLS:C1851305 abnormal dysplastic fused sacrum