Summary

This study evaluates the long-term sustainability of outcomes after multi-ligament reconstruction for multi-ligament knee injuries, revealing stable functional outcomes after three years but significant progression of osteoarthritis in the patellofemoral and medial tibiofemoral compartment.

Abstract

Background

The long-term outcomes of multi-ligament reconstructions (MLR) for mutli-ligament knee injuries (MLKIs) remain unclear, with concerns about rapid progression to osteoarthritis (OA) and limited data on the ability to sustain sports and work activities.

Purpose

This study aims to assess the long-term sustainability of patient-reported outcome measures (PROMs), return to work (RTW), return to sport (RTS), and the detailed progression of OA in patients who underwent MLR following MLKIs.

Methods

A prospective cohort study was conducted on 60 patients with Schenck grade I or higher MLKIs who underwent MLR between 2013 and 2020, without loss to follow-up. Evaluations occurred at three time points: injury (T0), early post-injury (T1, mean 3.4 years), and late post-injury (T2, mean 7.2 years). PROMs, including IKDC, ACL-RSI, and KOOS, as well as RTW and RTS, were analyzed. Work activities were categorized as sedentary or manual using Saltin-Grimby scale while sports participation was categorized into four levels per the IKDC scale. OA progression was assessed through diagnostic arthroscopy (Outerbridge [OB] grade >2, lesion size >1 cm²) at T0, weight-bearing radiographs (Kellgren-Lawrence [KL] grade ≥2) at T1 and T2, and MRI (Modified Outerbridge Classification [MOC] grade >2) at T2. Statistical analysis included paired t-tests for continuous variables and Chi-squared tests for categorical variables.

Results

The cohort (age 38.9 ± 11.1 years, 78% male, BMI 26.3 ± 5.2 kg/m²) included KD I (40%), KD III (32%), KD IV (12%), and KD V (10%) cases. No significant differences were observed in PROMs between T1 and T2, including all KOOS subscales. Participation in IKDC level 1 and 2 sports significantly decreased from 80% at T0 to 38% at T1 (p< 0.01) and remained stable at T2, while level 3 sports participation increased from 20% at T0 to 62% at T1 (p<0.01) and remained stable thereafter. Professional reorientation was significantly more common among manual laborers (33%) compared to sedentary workers (5%) (p=0.025), with the proportion of manual laborers decreasing from 30% at T0 to 20% at T1 and remaining unchanged at T2. At T0, 42% had OB grade >2 cartilage damage; radiographic OA (KL ≥2) was observed in 43% at T1, increasing to 65% at T2 (p=0.01). OA progression was most pronounced in the medial tibiofemoral and patellofemoral compartments. In the medial compartment, 60% of patients had cartilage damage at T0, whereas OA was present in 20% at T1 and increased to 45% at T2 (p = 0.01). In the patellofemoral compartment, OA increased from 43% at T0 to 55% at T1 and 81% at T2 (p = 0.03). No significant changes were observed in the lateral compartment, with 20% at T2.

Conclusion

This study highlights that the long-term sustainability of functional outcomes following multi-ligament reconstruction for multi-ligament knee injuries is generally achieved within the first three years post-injury, with minimal further deterioration observed thereafter. Osteoarthritis progression is the most pronounced in the patellofemoral and medial tibiofemoral compartment.