Progressing Toward, and Recovering From, Knee Replacement Surgery: A Five‐Year Cohort Study

OBJECTIVE: To determine the trajectories of preoperative worsening and postoperative recovery for both the index knee and the contralateral knee of patients undergoing knee replacement surgery. METHODS: Of the 4,796 subjects in the Osteoarthritis Initiative cohort study database, we examined 5-year data from 177 patients who underwent isolated unilateral knee replacement surgery and no other joint replacement surgery. Patient-reported outcomes captured domains defined by the International Classification of Functioning, Disability, and Health. Domains of knee structure and function, activity limitation, and participation restriction were examined using growth-curve modeling over 5-year periods prior to and following surgery. RESULTS: Preoperative worsening of the index knee was substantial in all domains of knee impairment, activity limitation, and societal participation. Pain intensity worsened only slightly from 5 years to 2.5 years prior to surgery, but worsened by ∼2 points (0-10-point scale) during the 2.5 years prior to surgery. Trajectories of improvement following surgery varied depending on the outcome measure. The contralateral knee also changed over time, such that by ∼2 years following surgery, pain was worse and by 3 years, activity limitation was worse in the contralateral knee as compared to the index knee. CONCLUSION: Patients who elect to undergo knee replacement surgery demonstrate perioperative trajectories of change that influence most health domains for both the index knee and the contralateral knee. After a period of no change, escalation of pain and worsening functioning in the index knee begins ∼2.5 years prior to surgery, which may be a key trigger for surgery.