Toward functional integration of 3D-printed meniscal scaffolds: A materials-driven systematic review of preclinical evidence and translational framework.

PURPOSE: Meniscal injuries are among the most common knee disorders and a major risk factor for osteoarthritis. Although meniscectomy provides short-term symptom relief, it irreversibly alters joint biomechanics, underscoring the need for regenerative strategies. Advances in additive manufacturing and biomaterials science have enabled three-dimensional (3D)-printed meniscal scaffolds with controlled architecture, tunable anisotropy and tailored biological functionality. This systematic review critically evaluates preclinical in vivo evidence on these strategies and identifies key factors influencing their functional integration and translational potential.

METHODS

A systematic literature search was conducted in PubMed, Web of Knowledge and Scopus up to September 2025, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Included studies involved preclinical in vivo models of meniscectomy evaluating 3D-printed meniscal scaffolds with reported mechanical and biological outcomes. Data extraction focused on biomaterials, fabrication techniques, scaffold design, mechanical performance and regenerative outcomes.

RESULTS

Twenty-three studies met the inclusion criteria. Resorbable polymer-based scaffolds, predominantly polycaprolactone, were most frequently investigated. Biofunctionalisation strategies-including cellularisation, biochemical cues and hydrogel-polymer composites-were widely employed. Most studies used rabbit models. Outcomes revealed a dynamic interplay between material composition, architecture, degradation kinetics and biological integration. An initial decline in mechanical properties was followed by progressive maturation, in some cases approaching native anisotropic behaviour and correlating with cellular infiltration and matrix deposition. Biofunctionalised scaffolds consistently demonstrated improved cartilage preservation compared with meniscectomy alone. However, heterogeneity in experimental design and reporting standards limited cross-study comparability.

CONCLUSION

3D-printed meniscal scaffolds show promising preclinical potential for promoting tissue regeneration and preserving joint integrity. To bridge the gap between experimental findings and clinical application, this review introduces a structured reporting checklist identifying key material, structural and biological determinants of successful scaffold integration. By promoting methodological harmonization and standardized outcome assessment, this framework aims to enhance cross-study comparability and support the stepwise clinical translation of next-generation bioactive scaffolds for meniscal injuries.

LEVEL OF EVIDENCE: N/A.