What are the long term effects of having spondylolisthesis?

Depends: Most people with spondylolisthesis lead normal lives. A minority may consider surgery.

Usually none other: Than some back pain but occasionally leading to spinal stenosis or a disc herniation with 10% needing surgery-this is for the congenital or isthmic type. The degenerative or acquired type typically seen in postmenapausal females can lead to back pain & spinal stenosis with 30% needing surgery.