Subdural hygroma-related heterotopic ossification in a patient with a stroke: a case report

This study presents a patient with a stroke who had total paralysis of his left-side limbs after intracranial haemorrhaging, who later experienced partial weakness of the right-side limbs after a subdural hygroma. Both conditions occurred without major trauma. He received two separate operations, a craniotomy and placement of a ventriculoperitoneal shunt, before the appearance of the subdural hygroma.

According to the literature, heterotopic ossification is often reported with major trauma-associated diseases, but is less frequently found in patients with non-traumatic conditions, from which this patient suffered. Although the patient had experienced no major trauma, he had multiple heterotopic ossifications on the side of the subdural hygroma-affected limbs, which exhibited better motor control and were less spastic than those of the opposite side. These heterotopic ossifications were around joints of the hip, knee and shoulder on his right side, as proven by plain radiography and a triple-phase bone scan and resulted in marked limitations of joint motions. This patient thus had major disabilities of his limbs bilaterally.

The occurrence of heterotopic ossifications in the less-paretic limbs might have worsened this patient's functional outcome.