RESUMEN
The medial shelf or the medio-patellar plica is a synovial fold runs along the medial wall of the knee. From June 1991 to March 1993 at Orthopedic Department of Assiut University Hospital, 27 patients of anterior knee pain underwent arthroscopy and prooved to be pathologic plica. There was no response from the medical treatment. It was not easy to diagnosis certain cases of medial plica in such patients. Athroscopy is an excellent tool for visualizing and evaluating the pathologic plica. By arthroscopy, removing of 1 cm of the plica substance down to the base was performed. After releasing of the fibrotic plica; ensure that it no longer impinges on the medial femoral condyle. In this article; etiology; material; arthroscopic evaluation and follow up are discussed