please click on image to enlarge

http://www.google.com.eg/imgres?imgurl=http://www.scielo.br/img/revistas/rb/v39n3/en_a04fig01.gif&imgrefurl=http://www.scielo.br/scielo.php%3Fpid%3DS0100-39842006000300004%26script%3Dsci_arttext%26tlng%3Den&usg=__-KbAi_xtT9HcXB556JvPTJ0XuvI=&h=437&w=565&sz=180&hl=ar&start=14&sig2=CHPN7_GsE8QRCnXOWRKGPA&zoom=1&itbs=1&tbnid=hVVzMV3yPA6WmM:&tbnh=104&tbnw=134&prev=/images%3Fq%3DCHONDROMALACIA,KNEE,MRI%26hl%3Dar%26sa%3DG%26gbv%3D2%26tbs%3Disch:1&ei=KgPlTOSELMmWhQeE0qy_DA