Fibrodysplasia ossificans progressiva: Diagnosis with ultrasound

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare connective tissue disease, diagnosed by genetic testing. This is the first report in English literature wherein an ultrasound examination suggested this specific diagnosis. In this case, a two month old girl presented with bi-parieto-occipital swellings that were being managed as subgaleal haematoma. The parents were anxious that there was no resolution of the swellings. The suspicion of FOP was raised during the ultrasound examination where a review of the images prompted a questioning of the parents about other lesions in the body. Ultrasound examination of a lump in the thigh revealed calcifications in the vastus lateralis muscle. The appearances on the ultrasound combined with the presence of hallucis valgi suggested a diagnosis of FOP. The diagnosis was subsequently confirmed by genetic studies. This case highlights the need for good communication between the physician, patient and the imaging department.