Proximal superomedial portal in arthroscopy of the knee.

Abstract

The proximal superomedial portal is placed 4 cm proximal to and in line with the medial edge of the patella. From this position, a 30 degrees arthroscope approaches the midline at a 30 degrees angle providing a "straight on" view of the patellofemoral joint. Passing the scope down the patellofemoral joint allows visualization of the anterior horns of both menisci, the tibial attachment of the anterior cruciate ligament, and the anterior fat pad, but the view on the monitor is upside down. To correct the orientation, the television camera is turned upside down. Both anterior portals are available for instrumentation. Both gutters, including the periphery of both menisci, can be fully viewed from the proximal portal. The menisci appear vertically oriented on the monitor, and the television camera is rotated 90 degrees to provide the usual horizontal orientation. The routine use of this portal is facilitated by using a cannula system, so that the cannula used initially for inflow-outflow irrigation remains in place and the scope is passed through it for viewing.