This study is a prospective, randomized, double-blinded, placebo-controlled study of the drug colchicine in the acute postoperative period for patients who are undergoing a total knee arthroplasty (TKA). Patients aged 18 years or older who are undergoing TKA will be invited to participate in the study. The primary endpoint of this study is to determine if colchicine, an anti-inflammatory medication commonly used for gout attacks, will decrease the postoperative pain of patients undergoing elective TKA.

This study is a prospective, randomized, double-blinded, placebo-controlled study of the drug colchicine in the acute postoperative period for patients who are undergoing a total knee arthroplasty (TKA). Patients aged 18 years or older who are undergoing TKA will be invited to participate in the study. The primary endpoint of this study is to determine if colchicine, an anti-inflammatory medication commonly used for gout attacks, will decrease the postoperative pain of patients undergoing TKA.

In doing so, we will utilize a 3-arm approach with two experimental groups and one placebo group. Qualifying subjects will be randomized 1:1:1 to Group A receiving a 1.8 mg loading dose of colchicine, Group B receiving the same loading dose + 0.6 mg maintenance dose of colchicine to be taken twice daily, and Group C receiving a placebo.

Regarding study procedures, standard preoperative and intraoperative procedures will be employed to ensure experimental and control groups have a nearly equivalent experience before the intervention. Subjects will be discharged with the same ambulation instructions and physical therapy regimens. Aside from the experimental drug, patients will receive the same postoperative pain medications upon discharge.

Research staff in the Geisinger pharmacy will receive and prepare the oral medication for dispensing, which will include randomizing identification numbers to colchicine or placebo, labeling packages with study identification numbers and subject information, and ensuring there is no visible method to discern colchicine from placebo. Colchicine is to be stored at room temperature.

Providers and subjects will be blinded regarding whether the subject will receive a colchicine loading dose + the placebo pills for maintenance doses, a colchicine loading dose + colchicine for maintenance doses, or the placebo pills for both. Group A will receive a 1.8 mg loading dose of colchicine by mouth on postoperative day 0 and will be instructed to take a placebo by mouth twice daily on postoperative days 1-3. Group B will receive a 1.8 mg loading dose of colchicine by mouth on postoperative 0 and will be instructed to take a 0.6 mg maintenance dose of colchicine by mouth twice daily on postoperative days 1-3. Group C will receive placebo dextrose pills by mouth on postoperative day 0 and will be instructed to take the placebo by mouth twice daily on postoperative days 1-3. Subjects will be sent home with an adequate supply of pills for postoperative days 1-3 and instructions on use.

The procedure for measuring the study variables is as follows:

Subjects will receive a post-operative pain journal upon hospital discharge on postoperative day 0. The journal will include three time points (morning, midday, and bedtime) in which they will record a VAS pain score ranging from 0-10 for post-operative days 1-3. The journal will also include a box for subjects to record the total pills of the prescribed postoperative opioid they have taken each day on postoperative days 1-3. Lastly, the journal will include a checkbox at the end for subjects to record whether they have experienced known colchicine-related side effects on postoperative days 1-3 such as nausea, vomiting, diarrhea, and abdominal pain. For evaluation of KOOS-JR scores and knee flexion, subjects will complete the 7-question KOOS-JR questionnaire at their 2-, 6-, and 12-week post-operative visits, and at these visits, a member of the research staff will determine the subject's knee flexion. Lastly, regarding the assessment of 90-day postoperative complications, the researchers will conduct a review of the subject's EHR.

Inclusion Criteria:

• Patients 18 years or older undergoing elective total knee arthroplasty for osteoarthritis.

Exclusion Criteria:

• Subject has impaired hepatic function (Child-Pugh Class >B)
• Subject has impaired renal function (GFR < 60 ml/min/1.73 m2)
• Subject has known adverse reaction to colchicine
• Subject has chronic opioid use (Filled opioid medication twice within 6 months of surgical date)
• Subject is pregnant or expecting to become pregnant during the time of the study associated with colchicine exposure (postoperative days 0-3)
• Subject is unable to provide informed consent
• Subject is actively prescribed medication that interact with colchicine in a manner that would increase the risk of colchicine toxicity, i.e.:
• Antifungals: Ketoconazole, itraconazole, fluconazole, etc…
• Macrolides : Clarithromycin, erythromycin
• HIV protease : Ritonavir, Atazanavir, saquinavir, etc...
• Ca2+: Verapamil and Diltiazem
• Cyclosporine
• Danazol
• Amiodorone
• Quinidine
• Anti-hepaciviral combinations
• Grapefruit juice
• Statins: atorvastatin, lovastatin, simvastatin, etc…
• Gemfibrozil and other fibrates
• Digoxin