[Patient factors influencing preoperative expectations of patients undergoing total knee arthroplasty]

To investigate the expectations of patients for total knee arthroplasty (TKA), and to analyze its influencing factors.

Experimental design: Single center, retrospective, multiple regression analysis. The data including the age, height, and weight of 108 patients undergoing unilateral TKA due to end-stage osteoarthritis were obtained. The patients' preoperative Hospital for Special Surgery (HSS) knee arthroplasty expectation score, the Western Ontario and McMaster Universities (WOMAC) score, Knee Society score (KSS), the MOS 36-item short-from health survey (SF-36) score, and visual analogue scale (VAS) were evaluated, and the 30-second chair-stand test (30-CST), 40-meter fast-paced walk test (40-FPWT), 12-level stair-climb test (12-SCT), 3-meter timed up-and-go test (TUG), 6-minute walk test (6-MWT), and recorded daily steps for 7 consecutive days were performed. The SPSS 22.0 software was used for statistical analysis. The observed values of various data were described. Pearson correlation analysis was used to evaluate the correlation between various parameters, and the multi-factor linear regression analysis was used to investigate the influencing factors of the patients preoperative expectation scores.

The average expectation score of this group of patients was 58.98±5.44. In the Pearson correlation analysis, the patient's preoperative expectation had a weak correlation to the result of the patient's 12-SCT, TUG, 6-MWT, KSS function score, and SF-36 mental component score (correlation coefficient 0.1-0.3). The patient's preoperative expectation had a moderate correlation to the patient's daily average steps, 30-CST, 40-FPWT, KSS, WOMAC and its pain, stiffness, function scores, SF-36 physical functioning, role-physical, bodily pain, vitality, and physical component score (correlation coefficient 0.3-0.6). In the multivariate linear regression analysis, only the results of 30-CST and the role-physical, bodily pain and vitality in the SF-36 scale were related to the patient's expectation score (P < 0.05).

The estimated expectation score of patients before TKA is not high. Patients with more severe preoperative pain, worse physical function, and lower overall health are more eager to improve after surgery. Thus surgeons must communicate fully with patients with unrealistic expectations before surgery in order to obtain more satisfactory results postoperatively.