segment a region in image using pixel coordinates

I want to segment the cartilage (masked by black lines) from the knee. I have the boundary values stored in a nx2 double matrix ( 2 of them, one for the inner and one for the outer boundary). Any help will be much appreciated! Here is the image

Answer 1

[Rik]

You can connect the two at the ends and then generate a mask with inpolygon, or a similar strategy.