if you feel the chick is alive yet and having a hard time getting out, you can CAREFULLY open up the shell above the air sack, and hopefully the beak has at least broken into the air sack, and then from there the chick should be able to do it..but you could observe better, and help if need be.
By allowing the chick to pierce the inner membrane this will minimize any bleeding of the membrane. The spot is then marked with a X. Then, at the X, the shell is broken away to the extent of the air space remaining in the shell. Do not tear away the membrane any more than the chick already has. If too much of the membrane is torn while it is still wet, excessive bleeding will occur which weakens the chick and can be fatal to the chick.
Once the shell is broken away, the egg is placed back in the hatcher for approximately 12 hours. Remove the egg and spray the membrane with a fine mist of water. Gently peel the membrane back to the line of the already broken shell. Gently grasp the chick's beak and pull the head and neck out of the shell. Place the egg back in the hatcher and allow the chick to complete hatching on its own. Allowing the chick to struggle to hatch will ensure that the remaining yolk sack is completely pulled inside the chick's belly.
I'd say if you don't see any shell pipping at all on day 57 or 58 it won't happen without help.
Dan