Biological Strategies to Enhance Healing of the Avascular Area of the Meniscus

Abstract

Meniscal injuries in the vascularized peripheral part of the meniscus have a better healing potential than tears in the central avascular zone because meniscal healing principally depends on its vascular supply. Several biological strategies have been proposed to enhance healing of the avascular area of the meniscus: abrasion therapy, fibrin clot, organ culture, cell therapy, and applications of growth factors. However, data are too heterogeneous to achieve definitive conclusions on the use of these techniques for routine management of meniscal lesions. Although most preclinical and clinical studies are very promising, they are still at an experimental stage. More prospective randomised controlled trials are needed to compare the different techniques for clinical results, applicability, and cost-effectiveness.

Adipose Stem Cells Incorporated in Fibrin Clot Modulate Expression of Growth Factors

“…27 Because fibrin clots capture platelets, they produce similar growth factors to platelet-rich plasma but also provide a structural support and a scaffold for cellular ingrowth, while serving as a reservoir for growth factor release over time from incorporated cells. 18,28 The dense nature of the platelet-rich fibrin scaffold also provides a structural integrity that allows for arthroscopic suturing over a repair site. 29 The use of biologic and synthetic scaffolds to deliver stem cells for therapeutic benefit has become increasingly widespread.…”

Review of Arnoczky and Warren on the microvasculature of the human meniscus

“…In contrast, tears in the white-white zone have classically been treated with debridement and meniscectomy rather than repair given the low likelihood of successful healing of a repair in avascular tissue 8. However, recent studies have demonstrated that repair of meniscal avascular white-white zone yielded satisfactory outcomes,16 and there remains controversy over which tears are best treated with repair versus meniscectomy 6 7…”

In Silico Testing of the Ability of Meniscus Implant to Convert Compressive Loads in to Hoop Stresses

“…The polyvinyl alcohol (PVA) hydrogel [5,6] implant of Kobayashi et al [7] was one of the first non-porous permanent replacement approaches. Compressive strength and viscoelastic behavior of the material was highly similar to that of the native (human) meniscus, even after two years of implantation in a rabbit knee.…”