I had a fusion 2.5 years ago. The numbness down my leg gradually went away over time. I would say the healing process was 12 to 18 months. I did not have a brace.
I found walking is the best thing and i felt better just from walking. I still walk nearly daily and in winter do the elipical training.
the pain i had pre surgery i gone. I have had 2 surgeries on my lumbar region. I do still get achy at the end of the day. not perfect, but no longer in need of narcotics and no numbness down my leg.
keep up the walking, don't push yourself too hard. I took 5 weeks off work , and then 4 weeks working from home part time before I returned to the office.I didn't drive until i was off the pain meds.
take care. there is only so much surgery can do. allow yourself 12 to 18 months to recovery