4. Isthmic Spondylolisthesis
This highly complex-sounding condition describes what is known as a stress fracture. A stress fracture is a fracture that occurs not through a specific event, but through general ‘wear and tear’. In short, you have simply used the joint and placed pressure on it over a very long time which has eventually caused it to start giving out.
These kinds of fractures are among the most dangerous as they can often go unnoticed. A stress fracture can then cause a vertebral body to slip forward slightly onto the other. So for instance, the L5 might slip forward over the S1. This then causes ‘disc space collapse’ and the fracture and vertebral body slipping forward will cause the sciatic nerve to get pinched.