I have used an inversion table and recommended one for years. A consensus of what is probably about a hundred users (myself and first hand reports) suggest it is effective in helping control low back pain in about 80% of the users. It doesn't benefit everyone.
It seems effective for arthritis, degenerative discs, bulging or herniated discs, spondylosis (fancy word for arthritic changes), and spondylolisthesis (one vertebrae misaligned with another).
It seems to work best when used as needed, when there's an exacerbation in the pain, for about 5-10 minutes in the evening before going to bed. Some think it helps to soak in a warm bathtub prior to using the inversion table and some think it's better to soak after using the inversion table. Some think it helps to have a "refreshing beverage" while soaking in the tub to help relax. Some think it helps to take Aleve or ibuprofen before bedtime.
It is helpful to use additional traction by either holding onto dumbbells or other weights underneath the inversion table while inverted, or some tables have handles that allow you to push against the handles while upside down to increase the traction effect.
There are two downsides.
1. Your feet and/or ankles take a significant load while inverted so proper footwear (boots?) and/or padding are experimented with to find what's most comfortable.
2. Some people experience a headache if they hang upside down too long.
