Paddle placement for failed back surgery syndrome

Variation : Only one prior surgery -- Although the literature strongly continues to support considering spinal cord stimulation instead of reoperating, it also remains clear that if the patient has an obvious structural component to their continued pain and it can be readily addressed by a further surgery, then that surgery should still be performed first before stimulation. Such obvious structural components to one's pain might be a new herniated disk, broken hardware with a progressed listhesis, or severe stenosis above the level of a prior fusion. Decisions become trickier when the presumed structural component is less overt: fibrosis around a nerve root, foraminal narrowing, and facet arthropathy, possible pseudoarthrosis. Even with only a single prior surgery, if the patient has a less overt structural problem, reoperation is rarely indicated versus spinal cord stimulation, and the likelihood of a better outcome favors spinal cord stimulation.

Variation : The patient has only back pain -- While it is common to have predominantly back pain in these cases of failed back surgery syndrome “FBSS,” traditional spinal cord stimulation has been less successful than if leg pain is the predominant feature. However, with more recent developments (higher frequencies, burst patterns, subthreshold stimuli, and more sophisticated traditional systems), getting back pain relief is more reliable in the long term (i.e., more than 1–2 years) than it used to be. Often pain relief can only be achieved to the upper buttock region, even with a “successful” trial where low back regions were helped. While I still feel compelled to let the patient know ahead of time that managing their low-back pain is certainly possible and SCS is worth trying, it is often harder to obtain with programming and hold on to, although technology is continuing to improve in this area.

Variation : There have been no prior surgeries yet, just worsening back and leg pains -- This situation is a fascinating area for progress and development in spinal cord stimulation. While some components of the patient's pain in such a case can be neuropathic in origin, it is almost inevitably a mixed neuropathic/nociceptive picture. SCS can still be very effective in such cases, and with third party payors increasingly denying approval for what they see as nonoperative back and leg pain, patients who fail medical management and other less invasive therapies (e.g., physical therapy (PT), epidural steroid injection (ESI's), and radiofrequency ablation (RFA)) may be left with little else to try, other than SCS. The ability to perform a trial with SCS always makes this therapy an option to consider.

Variation : The patient had no prior injections -- This patient has a classic picture that readily provides a solid indication for trialing an SCS. Had she not had any steroid injections, epidural or medial branch blocks, she would still be a candidate for SCS in my view, but she may have more peace of mind moving forward with it if she knew she had also failed these injections. Success for the long term from a few injections in this kind of case is extremely rare, and there are risks, albeit very low. I would typically suggest her to try one or two, just to know, but if she adamantly refused to do them for some reason, I would still move forward to an SCS trial.

Variation : The patient had not tried muscle relaxants or any gabapentin -- Often a large component of FBSS is muscle spasm, widespread or focal, persisting and/or episodic. Not having tried a muscle relaxant is a mistake that is easily corrected. Many patients will need to stay on one for the foreseeable future even after the stimulator is placed. I see patients commonly, as well, who have been given one muscle relaxant, felt “spacey” or “loopy” or overly tired and then dropped it completely and not tried any of the four or five others available. Their primary care physician (PCP) or pain physicians should be able to run through these in a month or two to really see that none of them help before giving up on them. They are not addictive, and no one should have a problem prescribing them. Gabapentin is also helpful for neuropathic pain in many cases, although in my experience, it is rarely potent enough to allow patients to stay away from seeking further input and treatment with FBSS. Part of this is often because they are severely underdosed with gabapentin. The standard dose that needs to be tried, ramping up over about 3 weeks, is 1800 mg/day, typically split into three 600 mg doses. Many patients are given 100 mg/day or 300 mg doses only to take at night. These doses are wholly inadequate for the typical pain associated with FBSS. In most cases, both a muscle relaxant and adequate gabapentin should have at least been tried before moving to an SCS trial.

Variation : The patient was taking 10 mg Dilaudid and 40 mg MS-Contin every day without benefit and asks if she can have her meds refilled before surgery -- Of course, physicians have different styles and preferences. I do not like to have any role in managing a patient's pain medication, narcotics or otherwise, prior to surgery. After surgery, I do manage their medications until a sufficient time has passed to be notably reduced toward a baseline following resolution of surgical pain. For an SCS paddle placement, this is typically a few weeks. In this scenario, I would make this clear to the patient. However, these preoperative high doses of narcotics are going to make postoperative management very difficult. I tell patients if they can wean their narcotic requirement some amount prior to surgery it will make pain control after surgery much easier. That said, most of the time such patients cannot wean their medications much at all going into surgery, and it is in my view unreasonable to expect much reduction either. I try to make it very clear to patients ahead of surgery that our ability to control the surgical pain after surgery is not going to be easy. Usually, they want surgery anyway, it is difficult, and we eventually get through it.

Variation : The patient has actually more back pain than leg pain and a TENS unit worked well, but only used it a few times for 15′ at a time -- This is an interesting situation that I have encountered many times. Often, patients are told they should only use a TENS unit for 15′ or maybe 30′ per day. Perhaps they tried it in physical therapy. If the patient has benefit with it and particularly if the patient is on the thin side and also has predominantly low back pain as opposed to leg pain, then a TENS unit continuously, or nearly continuously, is a viable option to test before proceeding with an SCS trial.