The MRI appearance of a polyurethane meniscal substitute worsens if it matches articular cartilage lesions of the knee

OBJECTIVES: To evaluate the influence of chondral lesions of the knee in function and appearance on magnetic resonance imaging (MRI) of the meniscal implant Polyurethane (Actifit®). MATERIAL AND METHODS: 48 patients were implanted with Actifit® by postmeniscectomía syndrome. The chondral status of their respective compartment was graded at arthroscopy with ICRS scale. Were evaluated functionally Womet, IKDC, Kujala, EVA and satisfaction (0-4). The implant characteristics were evaluated with MRI scale Genovese, assessing its correlation with the degree of chondral damage and functional outcome RESULTS: Mean follow-up of 38 months (25-75). 16 patients had no chondral lesion, 14 had lesion grade II, 10 grade III and IV grade 9. Womet, Kujala improved IKDC and 36.2 ± 7.6, 32.3 ± 13.5 and 39.2 ± 8.1 to 75.8 ± 12.9 (p = 0.02), 75.5 ± 15.4 (p = 0.03) and 85.6 ± 13.4 (0.042), respectively. No relationship between the degree of chondral damage and functional outcome was observed. The shape and size of the implant in RM was worse with higher levels of chondral lesion (p = 0.023). A post-hoc analysis showed that this was only due to the difference between patients without chondral injury versus those with ICRS II-IV. The satisfaction was 3.6 ± 0.8 points. CONCLUSION: Implementing a Actifit® led to significant pain and functional improvement after a minimum follow-up of 2 years. The size and morphological MRI appearance of meniscal replacement polyurethane was better in patients without chondral lesions. No relationship between the degree of chondral damage and functional outcome was observed.