An Investigation on the Preconditions and Diagnosis Methods for Alien Hand Syndrome

Alien Hand Syndrome Unveiled in a Patient With Right Middle Cerebral Artery Stroke

Alien hand syndrome (AHS) is a rare but significant disorder, characterized by involuntary and often complex movements of one's hand. These movements seem to occur independently and unconsciously, separate from a person's intended actions.  We report a case of a 70-year-old male who presented to the emergency department with left sided hemiplegia following a stroke in the right middle cerebral artery (MCA) that affected the right temporal, parietal and internal capsule region. Upon additional inquiry, the patient reported experiencing involuntary, abrupt movements in his left upper and lower limbs particularly while attempting voluntary movements. As per the patient, these symptoms occurred prior to the onset of limb weakness. The diagnosis of AHS was made after excluding other differentials based on the clinical, metabolic and radiological picture.  Our patient exhibited unique symptoms and had a different presentation from that mentioned in the literature, as the onset of symptoms preceded the development of limb weakness typically associated with stroke. Involvement of the upper and lower limb and onset of symptoms prior to limb weakness make this case exceptionally rare. Moreover, acknowledging alien hand/limb syndrome as a distinct condition, separate from the broad category of post-stroke movement disorder, carries significant implications for both the management and prognosis of affected individuals.