John,

Are you being treated just for Spondylolisthesis, or is that in addition to another issue such as AS?

Grade 1 Spondylolisthesis means that the vertibrate are 25% or less out of line. Since 24% is Grade 1, one can become totally disabled due to it I assume.

AS/PsA DX in 1988

Retired on disability
in 2005 at age 44