Patients
Consecutive patients (18 to 85 years of age) scheduled for primary unilateral total knee arthroplasty from September 2019 to May 2020 were enrolled. The exclusion criteria included a diagnosis other than osteoarthritis (such as rheumatoid arthritis or bone tumour), a known allergy to rhEPO, an Hb level more than 130 g/L or less than 90 g/L, a history of a haematopoietic or haemorrhagic disorder, a history of deep venous thrombosis (DVT) or pulmonary embolism (PE), ongoing anticoagulant treatment with anticoagulant therapy (warfarin or heparin) within 1 week prior to surgery, ongoing treatment with rhEPO within 3 months before admission, preoperative hepatic or renal dysfunction or other underlying diseases such as serious cardiac and/or cerebrovascular comorbidities, and refusal to participate.