A Comparison Between Polyurethane and Collagen Meniscal Scaffold for Partial Meniscal Defects: Similar Positive Clinical Results at a Mean of 10 Years of Follow-Up

Purpose: To compare, at long-term follow-up, the clinical outcomes and failures of collagen and polyurethane meniscal scaffolds for the treatment of partial meniscal defects. Methods: Patients affected by partial meniscal defect with intact anterior and posterior meniscal attachments and an intact rim at the circumference of the missing meniscus were included, treated with a collagen meniscal implant or with polyurethane scaffold, and clinically evaluated by analysis of the subjective International Knee Documentation Committee score, the visual analog scale score for the evaluation of knee function and symptoms, and the Tegner score to assess the activity level. Results: After 3 patients dropped out, a total of 47 patients, comprising 31 men and 16 women, with a mean age of 43 +/- 14.1 years and mean body mass index of 25 +/- 1.4, were clinically evaluated up to a mean of 10 years' follow-up. The International Knee Documentation Committee score improved from 42.9 +/- 15.9 to 67.4 +/- 12.4 (P < .0005) in the polyurethane implant group and from 46.8 +/- 16.7 to 62.1 +/- 22.6 (P < .0005) in the collagen meniscal implant group. The visual analog scale score decreased significantly from baseline values of 5.4 +/- 2.3 and 4.4 +/- 1.7, to 3.4 +/- 2.5 and 2.7 +/- 2.4, respectively, at final follow-up in the polyurethane implant (P = .002) and collagen meniscal implant (P < .0005) groups. The Tegner score improved in both groups without reaching the preinjury activity level. No significant differences in the scores were found between the polyurethane and collagen scaffold groups. A total of 10 implants failed, 5 per group, for a cumulative failure rate of 21.3%, with no differences between the 2 scaffolds. Conclusions: The long-term comparison showed positive and similar results for both polyurethane- and collagen-based meniscal scaffolds, with an implant survival rate of about 80% at 10 years of follow-up and no differences in terms of pain, function, and activity level.