OK, you need to speak to a personal injury lawyer. They will discuss with you how strong a case you might have.
When one wants to sue a government for negligence, one needs to look at what system of maintenance is in place and whether the government stuck to that system, and whether that system is reasonable to catch quickly damage to public facilities in order to protect the population. That sounds complicated, but essentially it comes down to this: just because there was a crack in the sidewalk doesn't automatically make the city liable. Having said that, the city certainly has insurance so your lawyer won't be afraid to send them a demand letter.
You'll also need a lawyer to look over your medical issues, and talk to you about the impact on your life, in order to have a starting point for what your monetary damages will be.
Personal injury lawyers aren't hard to find, they usually advertise. Or you could ask family and friends if they've used someone they could recommend. If you've used a lawyer before, you could call them and ask for a recommendation to a personal injury lawyer as well. Failing all of that you can look online, like at lexpert.ca for a listing of lawyers in your area sorted by area of practise. Don't pay a lot of attention to "lawyer rating" websites, I've seen plenty of good lawyers who have been rated poorly by clients who didn't get everything that they were hoping, and I've seen plenty of...uh...less good lawyers rated highly.
You could call around and see who will give you a free consultation, bring your medical documentation with you.
Is that a good place to start? I can't tell you what your claim might "be worth" because I'd need to know a lot more about your injuries and about you.
I'll await your reply with question or comment. If I've answered you I'd appreciate a positive service reply, please. Ratings are how I get credit from the site for helping its customers.