Introduction
Knee osteoarthritis (KOA) is a degenerative disease and imposes a substantial burden on individuals’ daily functioning due to its high prevalence, incidence, and disability, especially in elder adults.1–3 Meta-analysis showed that OA has a higher risk of cognitive decline and dementia.4 Rapidly cognitive decline, a primary symptom of dementia, is a prognostic factor for the exacerbation of KOA symptoms.5
Neuroimaging evidence indicated that cognitive decline was associated with structural changes in the brain.6 The hippocampus, a key component of the limbic system, has been suggested as a sensitive biomarker for cognitive decline.7 This complex structure comprised multiple subfields, each performing distinct cognitive functions. For instance, the posterior hippocampus (including the hippocampal tail)…