Following PRISMA guidelines, a systematic search of PubMed, ScienceDirect, ProQuest, and Google Scholar was conducted. The initial search yielded 322 articles, which were screened by title and abstract, resulting in 16 articles for full-text review. From these, 12 case reports and series studies met the inclusion criteria: cases with a confirmed CSDH diagnosis and new-onset chorea, athetosis, hemiballism, or dystonia. Data on patient demographics, CSDH features, movement type, treatment, and outcomes were extracted and synthesized. Exclusion criteria comprised cases where the involuntary movement was clearly attributable to a pre-existing condition.

Chorea and choreoathetosis were the most frequently reported hyperkinetic movement disorders, followed by dystonia. These presentations occurred in a wide age range (12 to 83 years; M = 72.73, SD = 16.93). Surgical evacuation of the hematoma was the predominant treatment. In nearly all reported cases, patients experienced a complete resolution or marked improvement of their involuntary movements following surgical intervention, often within days to weeks. 

CSDH is a rare but critical reversible cause of hyperkinetic involuntary movements. The high rate of resolution post-surgery suggests a strong association. Proposed pathophysiological mechanisms include direct mechanical compression of basal ganglia circuits, transient ischemia from reduced cerebral blood flow, and altered neurotransmitter function, even in the absence of significant mass effect. CSDH should be considered in the differential diagnosis of any patient with acute or subacute onset of unexplained involuntary movements.