Background: This study aims to investigate the clinical and radiological efficacy of three-dimensional acellular scaffolds (MaioRegen) in restoring osteochondral knee defects. Methods: MEDLINE, Scopus, CINAHL, Embase, and Cochrane Databases were searched for articles in which patients were treated with MaioRegen for osteochondral knee defects. Results: A total of 471 patients were included in the study (mean age 34.07 +/- 5.28 years). The treatment involved 500 lesions divided as follows: 202 (40.4 medial femoral condyles, 107 (21.4 lateral femoral condyles, 28 (5.6 tibial plateaus, 46 (9.2 trochleas, 74 (14.8 patellas, and 43 (8.6 unspecified femoral condyles. Mean lesion size was 3.6 +/- 0.85 cm(2). Only four studies reported a follow-up longer than 24 months. Significant clinical improvement has been reported in almost all studies with further improvement up to 5 years after surgery. A total of 59 complications were reported of which 52 (11.1 experienced minor complications and 7 (1.48 major complications. A total of 16 (3.39 failures were reported. Conclusion: This systematic review describes the current available evidence for the treatment of osteochondral knee defects with MaioRegen Osteochondral substitute reporting promising satisfactory and reliable results at mid-term follow-up. A low rate of complications and failure was reported, confirming the safety of this scaffold. Considering the low level of evidence of the study included in the review, this data does not support the superiority of the Maioregen in terms of clinical improvement at follow-up compared to conservative treatment or other cartilage techniques.