What does straightening of the normal lumbar lordosis mean?

Less back curve: The normall backward curve of your low back is straighter than usual it generally believed to be a sign of muscular spasm barring other pathologic conditions, it is a nonspecific incidental xray finding this shape can be found in the asymptomatic and the symptomatic.

"I shape": The lumbar spine has a "c" shaped curve to it. If this begins to straiten (from any one of many conditions) we call that straitening of the lumbar lordosis. In this case the spine would look like an "i" rather than a "c".