Relation between low back pain and X-ray changes.  4.  Lysis and olisthesis. 
In a comparative study of 1024 low back pain and healthy subjects, prelysis was found in 16.4%, lysis in 10.5% and olisthesis in 2%.  No relation between prelysis and lysis, and low back pain was found.  Lysis seemed to be associated with a higher severity of low back pain.  All the subjects with olisthesis suffered from low back pain.  Based on these findings, it is concluded that lysis or pre-lysis should not be a ground for the exclusion of candidates to any occupation, but that olisthesis should, and that both lysis and olisthesis should be accepted as roentgenological findings in which the severity of low back pain may be higher, thus justifying a more prolonged sick leave.