It is likely NOT a true "swelling" (such as the swelling around a sprained ankle). Instead, you probably have an area of muscle spasms. Muscles can feel "swollen" and hard when a person has a back injury.
Let your doctor examine the area and ask if there is an anti-inflammatory or muscle relaxer that might help you.
Narrowing of the space that nerves of the spinal chord pass through, Usually caused by age, trauma or arthritis.
It means that even though there is compression of the material between the discs there is no interference or pressure being put on the nerves that pass between them to the body.
Information on L23 L45 L5 S1 In The Spine
This means that L5 (the bottom vertebra of the lumbar spine) has fractured and compressed (telescoped) into S1 (the top of the sacral bone), and that there is no compression of the spinal cord (That is a GOOD thing!!)... If you'll copy the following web address (Back.com) and paste it into your browser, you can see the pictures and description of what I'm talking about... http://www.back.com/anatomy-lumbar.html