What Causes Redness Of Skin On The Shin Of Leg?

my left shin is soft and leaves an indention when pushed in or when I wear tight socks...I also have a red irritated area to the right of my left shin...it is somewhat swolen at the service and is very itchy...I have been applying a triple antibiotic oinment to the area and it releaves the itch temporarily but is not making the red area go away...