Unossified Membranous Strips of the Parietal Bone Mimicking a Fracture in a Child Presenting With Scalp Swelling: A Case Report

We report a case of a one-month-old male infant who was found to have a parietal scalp swelling on physical examination, with no reported history of trauma. Non-accidental trauma was suspected, and a skeletal survey was conducted to rule out any other traumatic injury. The skeletal survey showed a suspicious parietal fracture in the scalp swelling region. The rest of the survey was normal. CT scan was performed due to suspected non-accidental trauma. CT imaging demonstrated bilaterally symmetrical lucencies in the parietal bones extending perpendicular to the sagittal suture. Given its morphology and orientation, the lucency was determined to be a normal variant rather than a fracture. The subgaleal collection was not a recent hemorrhage and represented a late-appearing subdural effusion. This case highlights the importance of differentiating fractures from normal developmental variants of unossified strips of membranous bone, as misinterpretation can lead to significant medicolegal and emotional consequences.