[Mid-term clinical outcome of total knee arthroplasty with domestic A3 posterior stabilized prosthesis].

To observe the mid-term clinical outcome of total knee arthroplasty (TKA) with domestic A3 posterior stabilized prosthesis. The clinical data of 342 patients (438 knees) who underwent primary TKA by the same surgeon from June 2012 to December 2013 in Peking University Third Hospital were retrospectively collected. The patients were divided into 2 groups according to the type of prosthesis: 107 patients (137 knees) with domestic A3 prosthesis, as domestic group; 235 patients (301 knees) with a kind of imported prosthesis, as the control group. In the end, 311 patients (390 knees) received complete follow-up.The postoperative knee maximum flexion angle, postoperative Hospital for Special Surgery Knee Score (HSS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), postoperative coronal mechanical axis alignment and hospitalization costs were compared between the groups.Paired -test was used to compare the preoperative and postoperative data in the same group, and independent sample -test was used to compare the data between the two groups at the same time points. The average follow-up time of all the patients was (5.6±1.1) years, and it was averaged for 64.8 months in the domestic group and 68.2 months in the control group.There was no significant difference in the HSS score and WOMAC score, the knee maximum flexion angle, and coronal mechanical axis alignment at the 3 months postoperatively and at the end of follow-up between the two groups (=-0.890, -1.610, 1.740, 0.620, all >0.05). In 2012, the average hospital cost was (24 879±1 627) yuan/knee in the domestic group and it was (49 611±1 589) yuan/knee in the control group (=-48.902, <0.01). In 2013, it was (38 393±2 773) yuan/knee in the domestic group, and was (55 931±3 533) yuan/knee in the control group (=-14.795, <0.01). It indicates that the domestic A3 posterior stabilized prosthesis brings comparable mid-term results with the imported prothesis and it reduces medical costs remarkably.