Insufficiency fractures of the sacrum. Twenty cases and review of the literature.

Over the past 10 years, 231 insufficiency fractures of the sacrum have been reported in the literature. These fractures, which are due to osteopenia, form a distinct subgroup of pathologic fractures. In 1.8% (n = 20) of the older-than-55-years female patients (total = 1,015) admitted to the authors' Rheumatology department between 1989 and 1991, a fracture of the sacrum was diagnosed. In all cases the diagnosis was confirmed with computed tomography. Frequency, age, sex, diagnosis, underlying diseases, and associated fractures of the 20 cases of insufficiency fractures of the sacrum are described and compared with those previously reported. Insufficiency sacral fracture as a cause of low-back pain in women older than 55 years of age is concluded to be a clinical entity.