Progressive Supranuclear Palsy Diagnosed After a Severe Fall Trauma in a Patient Who Experienced Episodes of Easy Falling.

Progressive supranuclear palsy (PSP) is characterized by parkinsonism, downward gaze disorder, and a tendency to fall due to degeneration of the basal ganglia, the brain stem, and the cerebellum. We report a case of PSP that was diagnosed following a traumatic hemopneumothorax caused by a fall while descending stairs. A 79-year-old man experienced lightheadedness and frequent falls for two years. He fell on stairs at home and was transferred to our hospital due to mobility issues. He was hospitalized and treated for traumatic hemopneumothorax. Neurological examination revealed vertical ocular motility disorder, positive Myerson's sign, increased muscle stiffness, and increased limb tendon reflexes. Brain MRI showed a hummingbird sign. In this case, a midbrain area of 58.1 mm2 was consistent with PSP. He had no medication history that could have caused falls. He was diagnosed with PSP based on clinical and imaging findings, and treatment with levodopa was initiated. Two months later, walking showed limited improvement, and living at home became difficult. He was discharged to a care facility. PSP is a risk factor for frequent falls in the elderly. PSP usually requires three to four years for diagnosis, although falls appear earlier than in other forms of degenerative parkinsonism. Additionally, PSP often results in repeated dynamic falls due to a decreased perception of danger associated with reduced frontal lobe function. As a result, the severity of trauma from falls in PSP tends to be higher than in other neurodegenerative diseases. Therefore, early diagnosis of PSP may help improve patients' quality of life and prevent trauma. Despite frequent falls over two years, the cause was not thoroughly investigated until the patient experienced severe trauma. The lesson from this case is the importance of a thorough neurological examination and sagittal MRI for elderly patients experiencing repeated falls, to consider the possibility of PSP. Furthermore, quantitative evaluation of MRI enhances the diagnostic accuracy of PSP.