Remote Tai Chi for Knee Osteoarthritis

Inclusion Criteria: * Adults aged 50 years or older with clinician diagnosis of knee osteoarthritis * Active patient within a participating healthcare system * A score of 40 (visual analog version) or greater on at least 1 item of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale (range of 0 to 100, with higher scores indicating greater pain). * Ability to provide informed consent * Access to a telehealth-capable device, such as a computer, tablet, or smartphone * Ability to complete study procedures remotely in English * If randomized to the Tai Chi group, willing to comply with the Tai Chi program (twice-a-week remote sessions for 12 weeks) * If randomized to the Routine Care group, willing to abstain from Tai Chi programs until completion of the study Exclusion Criteria: * Current participation in Tai Chi practice * Serious medical conditions (e.g., dementia, significant neurological deficits or neurodegenerative disorder, active cancer treatment, psychosis, sensory deficits) limiting the participant's ability to participate in the Tai Chi safely, as determined by the principal investigators * Prior total knee replacement or planned total knee replacement during the study period * Inability to ambulate independently or rise from a chair without assistance * Reports severe depression defined by a Beck Depression Inventory (BDI-II) score of 29 or more. * Reports suicidal ideations defined by a score on BDI-II item of 2 or 3 ('I would like to kill myself' or 'I would kill myself if I had the chance'). * Concurrent participation in another interventional trial within 30 days before enrollment