Meniscal allograft transplantation and scaffolds: a narrative review.

Background and Objective: Meniscal tears are the most common intra-articular knee injury, especially among young active individuals. While meniscal preservation is preferred, complex tears often require partial or total meniscectomy. Removing meniscal tissue alters biomechanics, reduces contact area, increases stress, and ultimately accelerates cartilage degeneration, raising the risk of osteoarthritis. To address symptomatic post-meniscectomy syndrome, meniscal allograft transplantation (MAT) and meniscal scaffolds have emerged as reconstructive options, each addressing distinct patterns of meniscal deficiency. This chapter aims to provide a narrative review of current literature on MAT and meniscal scaffolds, including advances in implant technologies and clinical outcomes. Methods: A narrative review of the current literature on MAT and scaffolds was conducted, encompassing key studies on management, indications, patient-reported outcomes (PROs), return to sports (RTS), survival rates, failure rates, and complications. Key Content and Findings: Meniscal substitution with allografts or scaffolds improves pain and function in patients with symptomatic meniscal deficiency, with meniscal scaffolds indicated following partial meniscectomy in the presence of an intact peripheral rim, and MAT reserved for patients with subtotal or total meniscal deficiency. Clinical outcomes and return-to-sport rates for allografts and scaffolds have shown significant improvement, with no clear advantage of one surgical technique over the other. These procedures are often performed in conjunction with other procedures, such as anterior cruciate ligament reconstruction (ACLR), high tibial osteotomy (HTO), and cartilage restoration, which generally yield good outcomes. Conclusions: Symptomatic post-meniscectomy syndrome remains a challenging clinical entity. Meniscal scaffolds and MAT represent complementary, non-competing reconstructive strategies, with selection dependent on the extent of meniscal deficiency, peripheral rim integrity, and patient-specific factors. The preferred method for allograft/scaffold processing and surgical technique remains a topic of debate. Ultimately, the decision often depends on the surgeon's preference and graft availability.