Meniscal allograft transplantation improves patient-reported outcomes in both minimal and moderate knee osteoarthritis at 1 and 2 years postoperatively

Abstract

Purpose: Severe cartilage damage and advanced knee osteoarthritis (OA) might be associated with poor outcomes of meniscal allograft transplantation (MAT). The purpose of this prospective follow-up study was to explore MAT survivorship and patient satisfaction among young patients with symptomatic meniscal deficiency and radiological OA of different Kellgren-Lawrence (K-L) grades.

Methods: Thirty-five consecutive MAT patients were prospectively followed up for 2 years. The lateral meniscus was replaced in 29 patients and the medial meniscus in 6 patients. Outcomes were assessed using the KOOS₄ composite score, KOOS subscales, Lysholm knee score, and OA K-L grade progression from weight-bearing knee radiographs. For the outcome analysis, patients were categorized into two groups: 19 in Group A (K-L classification 0-1) and 16 in Group B (K-L classification 2).

Results: In terms of KOOS₄ and Lysholm scores, the patients showed a clinically significant improvement from baseline to the 1-year follow-up (22.2 points, 95% CI 16.6-27.8 for KOOS₄ and 16.8 points, 95% CI 8.9-24.6 for Lysholm), and the improvement remained at 2 years (20.6 points, 95% CI 13.2-28.1 for KOOS₄ and 21.5, 95% CI 12.5-30.7 for Lysholm). At the 6-month follow-up, this improvement was not yet observed. Minor between-group differences were observed in the KOOS₄ and Lysholm scores for the K-L 0-1 and K-L 2 OA groups, but the estimates were imprecise with wide confidence intervals. A clinically relevant difference between these two study groups could not be found at any timepoint. The reoperation rate was higher in the K-L 2 group than in the K-L 0-1 group (31% vs. 11%).

Conclusions: MAT yielded improved patient-reported outcomes and subjective satisfaction at 1 and 2 years postoperatively. The differences from baseline exceeded the minimal clinically important difference (MCID) at all timepoints. The severity of cartilage damage and knee OA in terms of the K-L grade at the time of surgery did not affect the KOOS and Lysholm scores after the MAT procedure. Knee OA progression in terms of K-L grade worsening was not observed in any patients.

Level of evidence: III.

Keywords: Cartilage damage; Knee osteoarthritis; Meniscal allograft transplantation; Patient-reported outcomes.

Fig. 1

Mean change of KOOS₄ scores from baseline to follow-up at 2 years in all MAT patients

Fig. 2

Mean change of Lysholm scores from baseline to follow-up at 2 years in all MAT patients

Fig. 3

Mean KOOS₄ scores in Group A (K–L 0–1) and Group B (K–L 2) from baseline to follow-up at 2 years

Fig. 4

Mean Lysholm scores in Group A (K–L 0–1) and Group B (K–L 2) from baseline to follow-up at 2 years