Perioperative Vitamin C to Reduce Persistent Pain After Total Knee Arthroplasty

Drug: Patients in the intervention group will receive 2g Vitamin C orally within 4 hours of the start of the surgery followed by 500 mg of Vitamin C to be taken orally twice a day from post-op day1 to day 56.

Drug: Patients in the placebo group will receive identical placebo capsules taken orally within 4 hours of the start of the surgery followed by placebo capsules taken orally twice a day from post-op day 1 to day 56.