Rationale
Chondral or osteochondrale lesions of the articular cartilage are found in about 60% of knee arthroscopies. Since articular cartilage has a low intrinsic regenerative capacity and cartilage lesions may potentially lead to severe osteoarthritis, a variety of reparative techniques evolved that aim at covering of the cartilage defect, formation of cartilaginous repair tissue, and resurfacing of the articular cartilage.
Among others, bone marrow stimulating techniques are frequently used surgical options for the treatment of focal cartilage defects. The microfracture technique is a minimally invasive procedure that induces a healing response by establishing access to the subchondral bone marrow in regions of articular damage. It allows the influx of blood, blood-derived cells and bone marrow-derived mesenchymal stem and progenitor cells into the defect, forming a blood clot.
These mesenchymal progenitor cells have a multipotential differentiation capacity that allows development along the chondrogenic lineage and may be induced by growth factors from the subchondral bone to develop a cartilaginous repair tissue.
Modern developments focus now on cell-free implants which enhance the recruitment and concentration of mesenchymal stem by stabilizing them within the defect (AMIC = Autologous Membrane Induced Chondrogenesis). In addition to this biological aspect (“biological chamber”), the matrix/implant offers also a mechanical protection which prevent the tissue destruction or displacement during the regeneration phase. Therewith the rehabilitation process can be accelerated and the clinical performance is enhanced.
Various absorbable scaffolds are currently in clinical use after being tested for biocompatibility, mechanical strength, absorption rate/stability and porosity. CHONDROVEIL™ made of pure Poly-glycolic Acid (PGA,) offers high tensile and mechanical strength under physiological conditions which allows a reliable fixation with sutures, screws or absorbable pins.