Yes, you are safe to needle the paravertebral level in the cervical and lumbar spine with history of a spinal fusion. You are correct, in the event of a laminectomy, you would want to shorten the needle length. If the patient does not know the nature of their surgery, a shorter needle length is appropriate. Also, ENS would be a contraindication in these areas secondary to the hardware.

I have a patient who has a multi-level spinal fusion c2-t12 who has developed significant radicular symptoms stemming from lower lumbar spine.  How far away from the fusion site does needling with ENS need to be in order to be safe?