Paper 03: Patient Acceptable Symptom State (PASS) Characteristics 10 Years following ACL Reconstruction: A MOON Cohort Study
Authors:   MOON Knee Group, Huston Laura 
Published: July 2022

Objectives: From both a patient’s and clinician’s perspective, interpreting numeric values from patient reported outcome measures (PROMs) is not always straightforward to evaluate “success” of surgery. To better address this dilemma, a single validated question related to a patient’s acceptable symptom state (“PASS”) has been recently developed and incorporated into outcome studies. The question reads “Taking into account all the activity you have during your daily life, your level of pain and also your activity limitations and participation restrictions, do you consider the current state of your knee satisfactory? (yes/no)”. The study objective was three-fold. First, to determine what percentage of ACL reconstructed patients responded “yes” to the PASS question at 10 years following their index surgery. Second, to correlate PASS with IKDC, KOOS Pain, and Marx activity level scores. Third, to predict what variables lead to a patient saying ‘no’ on the PASS. Methods: As part of a longitudinal cohort, patients were asked to complete the PASS question in addition to completing other PROMs (IKDC, KOOS, and Marx activity level) at their 10-year follow-up. Continuous variables such as age, BMI, IKDC, KOOS Pain, and Marx at 10 years were summarized using medians and interquartile ranges (IQR). Categorical variables such as sex, smoking status, and meniscus treatment were summarized using counts and percentages. IKDC, KOOS Pain, and Marx at 10 years were compared between those who achieved an acceptable state and those who did not achieve an acceptable state using the Wilcoxon rank-sum test. A multivariable logistic regression model was built to predict who would fail to achieve patient acceptable state at 10 years follow-up. The predictors in the model included age at baseline, sex, BMI at baseline, and subsequent surgery. Model results were displayed using odds ratios, 95% confidence intervals and p-values. Data management and data analysis were performed using R software (Version 4.0; Vienna, Austria). All tests were two-sided, with an alpha level of 0.05. Results: A total of 325 patients (median age of 23 years; 155 [48%] males) completed the PASS survey. Of these, 87% (282/325) reported achieving a patient acceptable state, while 13 (43/325) did not achieve an acceptable state. Figure 1 shows the comparisons of the 10-year IKDC, KOOS Pain, and Marx between the two groups. All comparisons are statistically and clinically significant, suggesting that the median scores at 10 years are significantly lower in patients who did not achieve an acceptable state compared with those who did. The patients who reported not having an acceptable state (PASS=no) were 36.8 points worse on IKDC, 22.2 points worse on KOOS Pain, and 5.5 points lower on their Marx activity level scores. Multivariable regression analysis found that patients who had any subsequent surgery following their index ACL reconstruction were 2.5 times more likely to report an unacceptable patient symptom state (PASS=no) at 10 years (Table 1). Patient age, sex and BMI were not found to be significant risk factors. Conclusions: A high percentage of patients (87%) remain satisfied with their knee 10 years following their index ACL reconstruction. Large clinically relevant and statistically significant differences were observed on PROMs between those patients who answered “yes” versus “no” on PASS. The major risk factor for not being satisfied with their knee was having any subsequent surgery prior to a patient’s10-year assessment. [Figure: see text][Table: see text]