Drainage versus non-drainage in primary total knee arthroplasty without tourniquet: a prospective randomized controlled trial

INTERVENTION: Drainage :Drainage after opreation ;Non‐drainage:Without drainage after opreation ; CONDITION: Knee osteoartritis; Rheumatoid arthritis PRIMARY OUTCOME: blood loss;Hidden blood loss;BMI;Volume of drainage;Blood transfusion volume;Blood transfusion cases;Hb;Hct;Superficial infection cases;Dressing change;Ecchymosis;Tension vesicle;Length of hospital stay;Range of motion;HSS;Superficial temperature;VAS;Swelling;Deep venous thrombosis; INCLUSION CRITERIA: 1. Primary unilateral total knee artropasty; 2. Patients with Knee osteoartritis or Rheumatoid arthritis; 3. Able and willing to provide signed informed consent.