Summary

This study found that pediatric patients show significant KOOS score recovery after ACL reconstruction, particularly in symptoms and sport subscales, but achieving acceptable quality of life (QOL) is challenging, particularly in younger female patients with lower preoperative QOL.

Abstract

Introduction

The long-term recovery of knee function and patient-reported outcomes following anterior cruciate ligament reconstruction (ACLR) remains a critical area of interest, particularly concerning the achievement of Patient Acceptable Symptom State (PASS) across different Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales. The aim of this study was to evaluate progression of KOOS subscale scores over time identify predictors of achieving PASS for the KOOS Quality of Life (QOL) subscale in pediatric patients after ACLR.

Methods

An IRB-approved retrospective review of pediatric patients at a tertiary care center, ages 10-21, who underwent a primary ACLR from 2013-2021 was performed. Demographics and clinical data were recorded, including KOOS scores assessed preoperatively and at 6 months, 1 year, and 2 years postoperatively. Analysis of variance and post-hoc analyses were used to examine how QOL compared to the other subscales. PASS achievement rates were calculated at each time point using threshold values established in prior literature (88.9 for pain, 75.0 for symptoms, 98.5 for activities of daily living (ADLs), 75.0 for sport, and 68.8 for QOL), and multivariate logistic regression was performed to identify predictors of KOOS QOL PASS.

Results

A total of 246 patients were included in this study. The mean age was 16.51 ± 1.72, and 66.7% were male and identified themselves as: 59.2% Asian/Other Race, 30.8% Black/African American, and 10.0% White. 63.1% had public insurance. Each KOOS score increases over time, but each follows a different trend, starting and ending at different points (Figure 1). Of note, QOL is significantly lower than all subscales at each time point (p < 0.001), with a mean preoperative score of 43.51 and a mean score of 77.15 at 2 year follow up. The KOOS subscales with the highest proportion of patients achieving PASS were symptoms (95.1%) and sport (94.9%), followed by 79.5% of patients achieving PASS in pain and ADLs, and 66.7% of patients with PASS in QOL (Table 1). Multivariate regression revealed that higher preoperative KOOS QOL (OR=1.10 [1.03, 1.20]), male sex (OR=10.78 [1.92, 103.59]), and older patients (OR=2.70 [1.41, 6.66]) had a higher odds of achieving PASS in QOL (Table 2). Conversely, patients with a higher preoperative KOOS pain (OR=0.91 [0.82, 0.99]) or chondroplasty (OR=0.05 [0.00, 0.64]) were significantly less likely to achieve PASS in KOOS QOL (Table 2).

Conclusions

KOOS scores demonstrate substantial recovery following pediatric ACLR, particularly in symptoms and sport subscales. However, the lower PASS rates for KOOS QOL highlight persistent challenges in achieving optimal quality of life post-surgery. Future interventions should focus improving the mental health of younger females with low baseline KOOS QOL and prevent this population from suffering persistently low QOL.