Are you going to a fellowship-trained spinal specialist? With the symptoms you describe, aside from the bony lump, you should call your doctor immediately.
When you start to have bladder or bowel problems, you need to be checked out immediately. The spinal nerves that control those functions are very sensitive and do not regenerate as well as other nerves. If you are having numbness and incontinence, these CAN be signs of cauda equina syndrome. Better to be on the safe side and have it checked than to wait and end up saying "if only I had known sooner."

Do you have a herniated disc? Where is your pain located.

You can read abouat CES here just so you have some basic information:

http://www.caudaequina.org/definition.html

I see no reason to assume this is spondylolisthesis unless you have already received that diagnosis. I've not heard of a vertebra moving to the point that it made a visible lump right under the skin. It generally does not slide in that direction. I can't imagine what it could be.

Perhaps others will chime in with some possibilities.

So what happened?

I have wanted to give up so many times, but today was the icing on the cake! I am so tired of incompetent doctors, IMO! I have a daughter who depends on me, I dont have the time to fill the "wait and see prescription". So, the appointment with my GP was completely worthless. She felt my back and said "well I'm not sure what that is" She then said all she could do was send me to the doctor that did my recent injections..."because he's an orthopedist" I then proceeded to tell this woman that he isn't an orthopedist, I repeated this 4 times. She then leaves the room and comes back 15 minutes later and says "well just go see the orthopedist that did your injections on WEDNESDAY" WHATEVER She then proceeds to tell me if I have problems over the weekend to go to Urgent Care...So I did. Now IMO, you would think that between these two appointments, someone would have ordered oh gee, I dont know, an MRI or X-RAY???? NOPE. He felt my back and said, you probably broke your tailbone, but we wouldn't know without an MRI, and you had to have fallen within the past week to break your tailbone, what did you do? None of this makes sense, cause I havent fallen in a long time.Then he tells me to go buy a donut pillow, and orders no further tests... Im at my wit's end. If it wasnt for my daughter, I would be in a mental institution right now. Well now my leg spasms are starting to burn, so Im gonna go ice my back, but now the pain is traveling from my left low back all the way up my spine....How much can the human body take?

I am so very sorry for everything that you have been through. I have a young daughter also, I am a little older than you, 35. I have had back pain for 2 years, no accidents, just told bad luck, genetics, etc..... I have had 2 back surgeries in the last year. My first neuro kept just throwing more meds at me instead of trying to figure out what was wrong. Finally did the first surgery and instead of better, got progressively worse afterwards. Again, he just kept handing out more meds. When he finally started running more tests, MRI, CT, and discogram and fd that the problem was the l4-s1 discs, the first words out of his mouth were" wow, that first surgery wasn't even needed. It would of never helped you." It made me so angry, I thought why didn't he do these tests before. What I am trying to say is that i understand the frustration of the wait and see approach. When you are in so much pain you want an answer now! By the way this neuro was supposed to be the best in the area. After having all these test and learning what was wrong I fd another dr in Tulsa which is about 2 hrs from where we live, but so worth the trip. From the first time I called I was transferred straight to his nurse and then his surg nurse asst called me back within 20 minutes also and spoke to me for almost 30 min, and scheduled appt. He is a wonderful caring neuro with a great staff. I have even been given home and cell numbers for his nurse so that I can contact day or night. Even given the number straight to nurses desk so I dont have to go through receptionist. I am now 6 weeks out from 2 level fusion. I like you was just about ready to give up, but in the last 3 days I am starting to feel better and getting back to normal. Still in a lot of pain but can finally feel things starting to get better. I you are not getting the answers you want from the drs you are seeing, then start searching for a different dr. There are wonderful drs out there that can and will help you. You are way too young to be this bad. Your daughter is young and needs her mommy now more than anything. I am so sorry for your pain and can sympathize with how stressed and helpless you are feeling. Things will get better though. Please dont give up hope yet. Get out there and find a dr willing to help you

Wow, you are going through a lot. So hard to navigate the healthcare system. I highly recommend finding a spinal center near you with a neurosurgeon for you to see.

I had x-rays and MRI of my lower back. Told by GP it was normal except for a small disc bulge. Went to NS and he said it looks normal when you are lying down, ordered flexion/extension x-rays of my back and I had a slipped vertebrae. My symptoms sound like yours, horrible spasms and incontinence.

Keep us posted as to how you are doing.

Best wishes to you,

Marianne