Design: Nationwide propensity-matched cohort, South Korean insurance database, 2010–2023
Population: 20,707 matched pairs of TKA patients with and without Parkinson disease
Primary outcome: 5-year vascular events and periprosthetic complications
Effect: Cerebrovascular aHR 1.11 (95% CI 1.07–1.16); no increase in periprosthetic fracture or infection

Using South Korea's national insurance database, researchers matched 20,707 patients with Parkinson disease diagnosed before unilateral total knee arthroplasty to patients without it, excluding anyone with pre-existing cardiovascular or cerebrovascular disease, and followed them for five years.

Parkinson disease was associated with slightly more cerebrovascular events, about 11% higher hazard. In patients diagnosed within five years before surgery there was also a small rise in cardiovascular events. Periprosthetic fracture and joint infection were not increased.

The increases are small and observational. The authors themselves warn against routine vascular screening because a patient has Parkinson disease.

The practical point is reassurance on the joint, with attention to the person: blood pressure instability, autonomic symptoms and Parkinson medication timing deserve a plan around surgery.

Reassure patients with Parkinson disease that infection and periprosthetic fracture risk were not raised.
Plan Parkinson medication timing carefully around surgery to avoid missed doses.
Check for orthostatic hypotension and autonomic symptoms before knee replacement.
Do not order routine vascular screening for Parkinson disease alone.

Why it matters

It answers a common worry about joint complications and redirects attention to medical risk.

The statistics, in plain English

A hazard ratio of 1.11 means an 11% relative increase in the rate of cerebrovascular events; on a low baseline this is a small absolute difference. Database diagnoses cannot capture Parkinson severity, so sicker patients may drive the signal.