My dad had a herrmohagic stroke in 2020. it affected his left side. he still need assistance is some everyday chores. but lately last week, his left arm seems to be swaying repetitively on his own. he was a aware of that. is that a good or bad thing?

Maximum healing and recovery do occur following a stroke over a period of 18 months. Substantial improvement does not occur subsequently. Not feasible to comment on left arm swaying, which could represent a focal seizure or a movement disorder, without a direct exam. Suggest a follow-up with his neurologist.

His uncontrolled movements suggest hemiballismus, somewhat commonly seen after strokes. He should see his neurologist who can make proper recommendations once his movement disorder is confirmed, try to film for few seconds in case episodes are infrequent.