Case report: A 7-year-old boy was involved in a road traffic accident. A computed tomography scan revealed an acute subdural hematoma (ASDH) of the posterior fossa, traumatic subarachnoid hemorrhage, and distortion of the brain stem. Removal of the ASDH was completed 3.5 h after injury. After extubation, the patient rapidly recovered consciousness. He was able to follow commands, although he did not speak. He began to utter 14 days after the injury. His speech became normal 39 days after injury. A magnetic resonance imaging scan revealed a post-contusional change in the right cerebellum and an ischemic lesion in the pons.
Discussion: Immediate removal of the hematoma is the only therapy for patients with ASDH of the posterior fossa. Although any lesions of the dentate nucleus, red nucleus, thalamus, cerebral cortex, and pons, all of which are involved in this case, are able to cause mutism, his mutism was primarily caused by the severe ASDH of the posterior fossa. The transient nature of this syndrome suggests that the cause of the mutism is trauma-related edema and/or transient ischemia of these structures.