nerves are very slow to regenerate if at all. i have nerve damage in my arm, which has gotten better over the years, but it's been about 10yrs and there really isn't much of an improvment. Nerves do not repair very well at all. I agree with the other poster, you should contact a lawyer.
your getting muscle weakness because the muscles innervated by the severed nerve are no longer recieving innervation therefore are starting to atrophy. What you should do is go to a physiotherapist. they can electricly stimulate the muscles and maybe keep them from wasting away in the event your nerve does repair enough to have some function. They may also be able to help stimulate nerve growth, it's worth looking into anyway, especially if the affected hand is your dominant one.
| 
Median nerve damage during CT surgery. 
Linear Mode
