Integration of Polyurethane Meniscus Scaffold During ACL Revision is not Reliable at Five Years Despite Favourable Clinical Outcome

Purpose: The aim of this study is to evaluate the clinical outcome at five-years follow-up of a one-step procedure combining anterior cruciate ligament (ACL) reconstruction and partial meniscus replacement using a polyurethane scaffold for the treatment of symptomatic patients with previously failed ACL reconstruction and partial medial meniscectomy. Moreover, the implanted scaffolds have been evaluated by MRI protocol in terms of morphology, volume, and signal intensity.

Methods: Twenty patients with symptomatic knee laxity after failed ACL reconstruction and partial medial meniscectomy underwent ACL revision combined with polyurethane-based meniscal scaffold implant. Clinical assessment at two- and five-years follow-ups included VAS, Tegner Activity Score, International Knee Documentation Committee (IKDC), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Lysholm Score. MRI evaluation of the scaffold was performed according to the Genovese scale with quantification of the scaffold’s volume at one- and five-years follow-ups.

Results: All scores revealed clinical improvement as compared with the preoperative values at the two-and five-years follow-ups. However, a slight, but significant reduction of scores was observed between two- and five-years. Concerning the MRI assessment, a significant reduction of the scaffold’s volume was observed between one- and five-years. Genovese Morphology classification at five-years included two complete resorptions (Type 3) and all the remaining patients had irregular morphology (Type 2). With regards to the Genovese Signal at the five-years follow-up, three were classified as markedly hyperintense (Type 1), fifteen as slightly hyperintense (Type 2), and two as isointense (Type 1).

Conclusion: Simultaneous ACL reconstruction and partial meniscus replacement using a polyurethane scaffold provides favourable clinical outcomes in the treatment of symptomatic patients with previously failed ACL reconstruction and partial medial meniscectomy at five-years. However, MRI evaluation suggests that integration of the scaffold is not consistent.