Technical tips in orthopaedics: meniscal repair with use of an in situ fibrin clot.

The importance of meniscal preservation has become increasingly clear, and many authors advocate repair of the meniscus whenever possible, forgoing patient age and tear location. In accordance with the common goal of preserving meniscal tissue, we describe a simple technique to augment meniscal repairs with the use of an in situ fibrin clot. The site is prepared accordingly: the synovium directly above the tear site is abraded with a shaver, rasp, or small intra-articular banana blade. Next, the water inflow cannula is closed, and the outflow cannula is opened to vacuum suctioning, allowing collapse of the distended joint. Under these circumstances, negative intra-articular pressure is produced in the knee joint. This condition is maintained for a period of 1 to 2 minutes and induces bleeding from the abraded synovial site. The knee in a dependent position causes the blood to run down the synovial wall and into the meniscal cleft, pooling there and forming a clot adherent to the edges of the separated meniscal tear. This procedure has been found to be a simple and minimally invasive mechanism for clot placement. The exposed collagen of the meniscal tear provides an ideal surface for a relatively tenacious clot attachment. It provides the healing factors reported to induce successful meniscal healing.