Percentage of patients 18 years of age and older who obtained at least a 10% improvement in knee pain and/or function as measured by validated patient-reported outcome measures (PROMs) completed up to 90 days prior to and 9 to 15 months after undergoing primary total knee arthroplasty (TKA) surgery. PROMs include any validated measures of knee-related measures of pain and/or function, such as KOOS-Pain, KOOS-ADL, KOOS-PS, and KOOS-JR.