Sorry to hear you are injured.  you can still enjoy some of portland's cooler area's though...
1) Japanese Garden - pretty much one of the better gardens in the States
2) Powell's Books - HUGE, any literature you might want about any topic.
3) Waterfront - take a nice stroll
4) Hawthorne - This is one of my favorite districts in Portland.  Head shops, organic stores, hippie things, good vibes and food.  Its on the East side
there is always good music there will def be some people rollin through...
1) Sunday, June 22:  Snoop Dogg and Warren G at the Roseland theatre 7 PM All ages
Well it looks like that is the only legit show rolling through.
Hope this helps a little bit