The Nautilus Abdominal Crunch Machine is a Dinosaur! But it is the only way to do abdominal crunches!
I am not a big fan of ab crunches for neck pain, back pain, and/or sciatica relief or as an exercise strategy in general. However, the old style Nautilus Abdominal Crunch machine was and is an awesome exercise for people suffering from neck pain, back pain, and/or sciatica because it effectively isolates the abdominal muscles in a way regular crunches cannot.
That being said, you can check out this video and others at: The Bad Back Guy's Neck Pain, Back Pain, and Sciatica Relief Bloghttp://TheBadBackGuy.com