Scarring L4-L5 right neural foramen
“There is 0.6 cm right-sided spondylotic protusion with extrusion”. Spondylosis indicates bone spur. It is quite common to have a bone spur projecting out of the edge of the disc space. An “extrusion” is generally a referral to a disc herniation that has come out of the disc space.
It is possible that this compressive mass was missed during surgery or was evaluated and found to not be compressive so left alone. If however you have these continued symptoms, it would be best to get a TFESI (transforaminal epidural steroid injection) and keep track with a pain diary to determine if this level and lesion is causing some symptoms. If you gain good relief, you could be a candidate for a decompression at this level.
See https://neckandback.com/treatments/epidural-injections-and-selective-nerve-root-blocks-diagnostic-and-therapeutic/ and https://neckandback.com/treatments/pain-diary-instructions-for-spinal-injections/.
Your tight back symptom could be from the surgery, the compressive mass or the degenerative changes in the rest of your spine “I have new herniations at L2/3, L3/4 and L4/5”
Dr. Corenman