Twenty percent of adults found to experience postsurgical cognitive impairment following knee replacement surgery

Older adults aged 60 and up who previously had knee replacement surgery have experienced decreased activity in at least one region of the brain tasked with cognitive functions, according to a study led by the University of Florida. Meanwhile, the cognitive function of 15 percent of older adults in the study showed a decline in all brain networks.

• Researchers wanted to find out what causes problems in a patient’s cognitive functions after they undergo surgery. They used resting-state functional magnetic resonance imaging (RS-fMRI) to look at blood flow patterns in the brain while patients were inactive.
• The team studied imaging data to understand how changes in blood flow influenced connections in brain networks related to memory and how the patients chose people, places, and events that deserve their attention.
• Patients who showed the biggest post-surgery decline include those with worse working memory, those with slowed mental processing, and those with signs of brain aging (as seen in imaging scans). After surgery, mental decline is characterized by brain “fuzziness.” Those from the non-surgery group showed no changes in their brain scan.
• At least 23 percent of patients who had knee replacement surgery exhibited significant connectivity decline in at least one brain network 48 hours after surgery.

According to the authors of the study, more research is required to see whether changes in the brain network will be present three months or even a year after surgery.

Journal Reference:

Huang H, Tanner J, Parvataneni H, Rice M, Horgas A, Ding M, Price C. IMPACT OF TOTAL KNEE ARTHROPLASTY WITH GENERAL ANESTHESIA ON BRAIN NETWORKS: COGNITIVE EFFICIENCY AND VENTRICULAR VOLUME PREDICT FUNCTIONAL CONNECTIVITY DECLINE IN OLDER ADULTS. Journal of Alzheimers Disease. 6 February 2018;62(1):319–333. DOI: 10.3233/JAD-170496