Revisiting Parakinesia Brachialis Oscitans: You Yawn, I Move! A Scoping Review

Background: Parakinesia brachialis oscitans (PBO) is a rarely reported phenomenon in which a paretic limb moves involuntarily during yawning. The literature consists predominantly of case reports and small series, with limited comparative evidence.

Methods: We conducted a PRISMA-ScR-guided scoping review of PubMed, Embase, and Web of Science from inception to 28 August 2026, with backward citation searching. Eligible reports described one or more patients with an involuntary, stereotyped, yawn-locked movement of a paretic limb after a focal central nervous system lesion, with the lesion site reported on neuroimaging. Data included demographics, movement description, latency, lesion site, etiology, and outcome.

Results: Twenty-two reports describing 31 patients met the inclusion criteria. Most patients were men (67.7%), with a mean age of 56.1 years. PBO involved the upper limb alone in 29 patients (93.5%). Acute ischemic stroke was the most common etiology (83.9%). Lesions were often seen in the internal capsule (44.4%) and the corona radiata or subcortical white matter (40.7%). Onset ranged from immediate to four months after the lesion. Complete resolution was documented in 10 patients (32.3%), PBO persisted for up to three years in five, and outcome was not reported in 15 (48.4%).

Discussion: PBO is associated with focal lesions affecting distributed voluntary motor-control networks, frequently involving subcortical motor pathways. Although no mechanism has been established, the observations suggest a release of preserved brainstem and extrapyramidal circuits. Outcome was unreported in almost half the cases; prospective, standardized reporting is needed to clarify its course and prognostic significance.

Highlights

• This scoping review gathered 22 reports describing 31 patients with PBO after a focal brain injury.
• PBO involved the upper limb alone in 29 patients and lesions were most commonly subcortical, involving the internal capsule.
• Onset ranged from presentation to four months and PBO persisted for up to three years. However, the outcome was not reported in half of the included cases.