Midterm Outcomes of Meniscal Allograft Transplantation in the Adolescent Population.

Objectives: To report midterm outcomes following primary meniscal allograft transplantation (MAT) from a single surgeon in an adolescent population. Methods: A retrospective review was performed to identify adolescent patients <18 years old at the time of primary MAT from 1999-2016. International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales, and Lysholm scores were collected preoperatively and at 1-year, 2-years, and a minimum of 5-years follow-up. Results: Forty-four (female n=33; male n=11) of 62 identified patients (71%) met inclusion criteria with a mean follow-up of 9.5 ± 3.8 years (range: 5.0-17.7). Isolated MAT was performed in 27 (61.3%) patients. Common concomitant procedures included osteochondral allograft transplantation (OCA) (n=14, 31.8%), autologous chondrocyte implantation (ACI) (n=8, 18.1%), and anterior cruciate ligament reconstruction (ACLR) (n=6, 13.6%) (Table 1). Eleven patients (25%) required a reoperation an average 5.9 ± 4.5 years (range: 0.8 - 14.0) post-transplant. Three (6.8%) patients met criteria for failure, requiring revision MAT an average of 3.8 ± 1.1 years (range: 2.84.9) post-transplant. Graft survivability at 1, 2, 5, and 10 years was 100.0%, 100.0%, 93.2%, and 93.2%, respectively (Figure 1). When compared to preoperative scores, significant increases in Lysholm, IKDC, and KOOS subscales were observed at 1-year, 2-year, and most recent follow-up (Figure 2 and Supplemental Table 1). 90% of patients reported satisfaction with their current physical status. Conclusions: At midterm follow-up, primary MAT in the adolescent population resulted in predictable improvements in functional outcomes. These improvements were maintained at an average follow-up of 9.5 years. The meniscal reoperation rate was 25% with a 71.3% probability of being reoperation free at 5 years while graft survivability was 93.2% at 5 years. When compared to extant literature profiling MAT in the adult population, adolescents who undergo MAT demonstrate similar functional outcomes and graft survivability. [ABSTRACT FROM AUTHOR]