Is it abnormal for a lump to form on the lumbar spine three weeks after a lumbar laminectomy?

Yes it is?: Most likely you some complications check it out?

Yes: It is not normal but can happen due to a fluid collection forming known as a seroma or another type called a hematoma which usually resorb on their own. A spinal fluid leak can cause this or an infection but there would be other symptoms. As the tissue swelling goes down you may feel lump that is just a bony process remaining above & below the level where that bone was removed feeling like a lump.

YES: There may be scar forming over the spines process or hematoma. Needs 2 b looked @ 2 b sure it's not an accumulation of spinal fluid or a low grade infection. C ur surgeon.