Spontaneous obturator internus muscle haematoma: a new unpublished cause of ilioipelvic pain in haemophilia.

[pyomyositis]

Obturator muscles haematoma are rarely reported . The most often reported cases are primary pyomyositis or posttraumatic haematomas occurring during pelvic fractures . We firstly report herein two cases of spontaneous obturator internus haematoma (OIH ) in two haemophiliacs with inhibitor . Clinical data and imaging of two patients treated in our clinic are reported here according to previously defined criteria of OIH in posttraumatic situation . Both patients were children suffering from severe and moderate haemophilia A , respectively , with an inhibitor at the time of the event . The clinical feature was marked by an iliopelvic pain letting discussing hip haemarthrosis , appendicitis or iliopsoas haematoma . For both patients ultrasonography (US ) failed to provide the diagnosis . Careful and repeated clinical examinations eventually lead to suspect obturator haematoma which was confirmed by abdominopelvic computed tomography (CT ) and magnetic resonance imaging (MRI ). Respectively , high dose of FVIII or rFVIIa regimen allowed a rapid control of the muscular bleeding in the low and high responder inhibitor patients . Spontaneous OIH may be added to the differential diagnosis of iliopelvic pain in severe forms of haemophilia . US still often performed at first in such case remains unhelpful ; abdominopelvic CT or MRI should be performed to discriminate among different diagnoses , including OIH which stays probably undiagnosed .