What are rare consequences of severe cellulitus in the heel?

In 2009 I caused a really bad case of cellulitis because I tried to lift my wheelchair because it got stuck in sand on a sidewalk.

I am a spinal cord injury patient but had very good walking ability at the time and had strong legs.  3 years later I now have severe heel pain and severe platar fasciitus because I avoid using my right heel and instead use my under pads behind my toes.  

I've had x-rays and everything is normal.  No bone spurs etc.  

I think something rare happened and seek answers from the members of this forum.