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

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.

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).

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%).

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.

III.