Is a Tummy Tuck OK to Have with Herniated Disks?

Tummy tuck or abdominoplasty is a very common procedure, as is back problems like herniated disks. They do not go well together since your mobility and positioning is limited after a tummy tuck, and this position (stooped) is not favorable for pre-existing back pain. This can lead to aggravation of your back pain and a very hard recovery.
Be careful and discuss this with your spine and plastic surgeon.

As long as you have clearance from your spine surgeon regarding your herniated disks, you should be fine with abdominoplasty. Often, patients say that their back pain improves after abdominoplasty with rectus plications since the muscles are tightened during the procedure. Good luck.

If the herniations are not symptomatic and you have clearance from your back surgeon, an abdominoplasty might actually help. By removing the extra strain on your back from redundant skin and fat on your lower abdomen and tightening the abdominal muscles, which can stabilize your back anteriorly (from the front), some patients have reported improvement in their lower back problems. This would be especially true if a weight loss -if needed - occurs as well.

Not a GOOD idea. First have the disc treated to a improved level than consider cosmetic tummy surgery. This is the ONLY way I would operate on you.
From MIAMI Dr. B

It is worth remembering that a Tummy Tuck (Abdominoplasty) is a cosmetic procedure intended to improve appearance NOT improve function much less save lives. It would be regrettable if your new flat tummy was associated with worsening of your back condition.
The fact that you have NOT opted to surgically correct your herniated back disc(s) hints that either they are not operable (either too mild or too far gone/serious) or that you were deemed too much of a risk for surgery or decided not to undergo the procedure for whatever reason. Either way, I would seriously encourage you to CLEARLY have your spine surgeon advise you on the safety of doing a Tummy Tuck.