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Establishing the Minimal Clinically Important Difference and Patient Acceptable Symptom State After Isolated
Felicitas Allende1, Rodrigo Saad Berreta1, Zeeshan A Khan1
1Rush University Medical Center, Chicago, Illinois, USA.
Background:
Significant clinical improvements have been shown after a posterior medial meniscal root (PMMR) repair; however, there is a lack of understanding of their effect on patients' perspectives.
Purpose:
To (1) define the minimal clinically important difference (MCID) and the Patient Acceptable Symptom State (PASS) for patient-reported outcome measures (PROMs) after isolated PMMR repair; (2) investigate the role of preoperative, demographic, and intraoperative variables in predicting achievement of these thresholds.
Study Design:
Case series; Level of evidence, 4.
Methods:
Patients who underwent arthroscopic PMMR with a minimum of 2-year postoperative follow-up were included. PROMs, demographic variables, intraoperative details, and postoperative complications were recorded. PROMs analyzed include the International Knee Documentation Committee (IKDC) Score, the Knee injury and Osteoarthritis Outcome Score Jr (KOOS Jr), and the Veterans RAND 12 Physical Function (VR12 PF). MCID and PASS thresholds were calculated. Multivariate logistic regression analyses were conducted to identify factors associated with the attainment of the MCID and the PASS.
Results:
A total of 75 patients were included, and 5 progressed to arthroplasty within 2 years. Of the remaining patients, the MCID thresholds and percentage achievements were as follows: the IKDC, 10.17 and 84.3%; the KOOS Jr, 10.42 and 71.4%; and the VR12 PF, 6.08 and 60%. The PASS thresholds and percentage achievements were as follows: the IKDC, 67.81 and 60%; the KOOS Jr, 71.95 and 55.7%; and the VR12 PF, 47.75 and 52.9%. For the IKDC, a lower body mass index (BMI) and a lower preoperative score were predictive of MCID achievement, whereas a lower BMI and a greater preoperative score were predictive of PASS achievement. For the KOOS Jr, a lower BMI was predictive of PASS achievement. For the VR12 PF, younger age, lower BMI, Kellgren-Lawrence (KL) grade 1, and a lower preoperative score were predictive of MCID achievement, whereas lower BMI, greater preoperative joint space, KL grade 1, and a higher preoperative score were predictive of PASS achievement.
Conclusion:
This study defines the thresholds for MCID and PASS achievement at a minimum 2-year follow-up for the IKDC, KOOS Jr, and VR12 PF scores in a cohort of 70 patients undergoing isolated PMMR repair (72.9% women, mean age, 55.2 years). A larger portion of patients achieved the MCID (84.3%, 71.4%, and 60%) compared with the PASS (60%, 55.7%, and 52.9%). The most common predictors of MCID and PASS achievement included lower BMI and preoperative scores. Furthermore, younger age emerged as an independent predictor of MCID achievement for VR12 PF.
Insights
This study defines patient-reported outcome thresholds after posterior medial meniscal root repair. Lower BMI and preoperative scores predict better outcomes, with more patients achieving minimal clinical difference than acceptable symptom state.
Area of Science:
- Orthopedic Surgery
- Sports Medicine
- Biomedical Engineering
Background:
- Posterior medial meniscal root (PMMR) repair shows clinical improvements, but patient perspectives require further understanding.
- Assessing patient-reported outcome measures (PROMs) is crucial for evaluating the success of PMMR repair from the patient's viewpoint.
Purpose of the Study:
- To define the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) for PROMs after isolated PMMR repair.
- To identify preoperative, demographic, and intraoperative factors predicting achievement of MCID and PASS thresholds.
Main Methods:
- A case series of patients undergoing arthroscopic PMMR repair with at least a 2-year follow-up.
- Analysis of PROMs including IKDC, KOOS Jr, and VR12 PF scores; calculation of MCID and PASS thresholds.
- Multivariate logistic regression to determine predictors of achieving MCID and PASS.
Main Results:
- MCID achievement rates were 84.3% (IKDC), 71.4% (KOOS Jr), and 60% (VR12 PF).
- PASS achievement rates were 60% (IKDC), 55.7% (KOOS Jr), and 52.9% (VR12 PF).
- Lower BMI and lower preoperative scores were common predictors for both MCID and PASS achievement.
Conclusions:
- Established MCID and PASS thresholds for IKDC, KOOS Jr, and VR12 PF scores post-PMMR repair at 2-year follow-up.
- Higher rates of MCID achievement compared to PASS indicate that while many patients improve, fewer reach an acceptable symptom state.
- Predictors for improved outcomes include lower BMI, younger age, and specific preoperative knee conditions.
