Patients control preferences and results in knee arthroplasty.

PURPOSE: Patient engagement in a patient-physician decision-making process has been correlated with satisfaction and clinical outcomes. Aim of this study is to evaluate if patient control preference may also influence TKA results.

METHODS: One hundred and seventy-six patients (120w-56m, age 66 ± 9 years, BMI 28 ± 4) underwent TKA and were prospectively evaluated, before surgery and at 6 and 12 months. The preoperative assessment included the Control Preference Scale (CPS) and other scales measuring psychological aspects (STAI, BDI, TSK), as well as SF12 (physical and mental subscales) and the assessment of pain and function. Pain, function, and SF12 subscales were then used to evaluate the improvement at 6- and 12-month follow-up.

RESULTS: Pain, function, and SF12 scores improved at 6 and 12 months. CPS correlated with the outcome: pain and functional improvement at 6 months (p = 0.014; p = 0.003, respectively), patient function at 6 months (p = 0.022), improvement of SF12 physical subscale at 6 and 12 months (p = 0.027; p = 0.037, respectively), and satisfaction at 6 months (p = 0.033). Moreover, the multivariate analysis confirmed the importance of CPS regardless of other demographic, physical or psychological characteristics.

CONCLUSION: In contrast with previous literature findings, this study shows that patients with more propensity for control presented lower improvements of pain and function than those more prone to rely on the physician making the decision. Physicians should be aware that the patient control preference may influence the treatment outcome and undertake measurements to optimize patient participation in the shared process to optimize the chances of TKA success.

LEVEL OF EVIDENCE: IV.