ObjectiveTo compare the cost changes of total knee arthroplasty (TKA) before and after the cancellation of medical consumables addition, so as to provide reference for the national medical reform policy.MethodsThe patients treated with TKA between September 2018 and February 2019 were admitted as objects of study, and 372 of them met the selection criteria and were finally included in the study. According to the time node of cancelling the medical consumables addition (December 24, 2018), all patients were allocated to pre-cancelling and post-cancelling groups (n=186). The clinical data of patients (gender, age, length of stay, disease classification), and various treatment costs (the costs of diagnosis and treatment, examination, laboratory, material, anesthesia, bed, nursing, operation, drug, and others) were collected. And the changes of various costs and proportions before and after cancelling the medical consumables addition were compared.ResultsThere was no significant difference in gender, age, and disease classification between the two groups (P>0.05); the length of stay after cancelling the medical consumables addition was significantly longer than that before cancelling (t=2.114, P=0.035). There was no significant difference in the total cost of TKA before and after cancelling the medical consumables addition (t=0.214, P=0.831). Compared with that before cancelling the medical consumables addition, the cost of material was significantly reduced, and the costs of diagnosis and treatment, anesthesia, nursing, and operation were significantly increased (P<0.05); the costs of examination, laboratory , bed, drug, and others were basically stable, and the differences were not significant (P>0.05).ConclusionThe total cost of TKA is stable, the proportion of material cost is significantly reduced, the proportion of diagnosis and treatment cost reflecting the technical content of medical staff is significantly increased, which is in line with the expectation of the national policy of cancelling the medical consumables addition.