Adult primary unilateral TKA patients with less than 90° of knee flexion between 5 and 12 weeks after their index surgery will be screened for trial eligibility based on the inclusion and exclusion criteria above. Only patients from the protocol surgeons will be eligible to participate in this trial. MUA will be performed prior to 12 weeks after the index TKA. Patients will be randomized to either oral colchicine 0.6 mg twice daily for 6 weeks (treatment arm) or to oral placebo twice daily for 6 weeks in the placebo arm. All patients will follow a standardized post-MUA physical therapy protocol. Data will be collected prospectively, including study data collection sheets and medication diary. Other data sources will include office and inpatient medical records, operative reports, physical therapy records, hospital picture archiving and communication system (PACS) and radiology records. Outcomes will be collected at MUA, 6 weeks, 3 months, and 1 year.