Biparietal Thinning: Accidental Death by a Fall from Standing Height.

Biparietal thinning resulting in bilateral and symmetrical resorption and loss of thickness of the parietal bones is an uncommon to rare condition in the anthropological and clinical literature. This enigmatic condition of unknown etiology was first reported in the 18th century and has been variously described as a nonmetric trait, anatomical variant, anomaly, and pathology. Biparietal thinning presents grossly and radiographically as oval-shaped depressions in 0.25-0.8% and 0.4-0.5% of individuals and with a higher frequency in females over the age of 60 years. A review of the literature revealed only one example of cranial trauma associated with biparietal thinning and none of fatal trauma associated with this condition. This case reports a rare example of fatal trauma in an elderly man that resulted from a backward fall from a standing height and highlights the increased risk of craniocerebral trauma in individuals with this condition.