As new medical technologies further develop every day this
new pain management treatment is straight out of a science fiction story. For
those suffering from chronic pain, the idea of simply opening an app and
changing a setting to relieve their pain sounds too good to be true. But with a
spinal cord stimulator, this is totally possible. Sensory neurons wrap around
to the dorsal side of the spinal cord and continue this way up the spinal cord
to the brain. Placing a spinal cord stimulator which sends a low electrical
signal that disrupts these sensory pain signals from reaching the brain and
replacing them with a different one. This new signal is typically described as
tingling rather than a painful feeling. The issue with using a spinal cord
stimulator Is you are not treating the underlying causes of the pain. For
example, if the pain is due to a mechanical issue this will not be changed and
could cause more physical damage to tissues or joints that would not otherwise
occur if you could feel pain. Therefore, it is often used as a last resort
treatment.
The surgery is fairly simple, to begin the patient is mildly
sedated and two leads are placed in the epidural space typically in the lower
thoracic region. They are run along the entire length of the epidural space
with guidance from x-rays until they find their new home typically in the
thoracic region. The leads are maneuvered to locations associated with the
patient’s worst described pain. The sedation is lifted and the leads are
activated. After some calibrating to ensure all the right areas are “turned
off” the patient is hooked up to an external portable battery. After the trial,
if it was a success, they will leave the leads in and simply unhook the
portable battery and insert a little permanent battery much like a pacemaker
into the back under the skin. This battery is charged much like modern phones
with wireless charging capabilities. Once inserted under the skin, the patients
have full control over the device through the use of their phones. They can
change the intensities for different activities to block out or allow a certain
amount of signal. If for whatever reason the patient is not totally satisfied
worth the spinal cord stimulator there is the option to simply pull the leads
and the patient is left with nothing but a tiny incision scar. They could then
continue to pursue other options of treatment. This treatment bypasses the need
for steroids, opioids, and injections and helps proved patients' autonomy with chronic
pain treatment.
Nichols, T., Mandybur, G.,
& Orlando, M. (2021). Spinal Cord Stimulation, SCS. Spinal Cord Stimulation
| Cincinnati, OH Mayfield Brain & Spine. Retrieved September 29, 2022, from
https://mayfieldclinic.com/pe-stim.htm
Sivanesan, E. (2021, August
8). Spinal cord stimulator. Johns Hopkins Medicine. Retrieved September
29, 2022, from https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/treating-pain-with-spinal-cord-stimulators
Spinal cord stimulation is an extremely interesting subject, especially when you further understand its potential applications. Amongst its application as a means to cope with chronic pain, spinal cord stimulation can also have benefits for those impacted by spinal cord injuries (SCI). Spinal cord injuries, unlike a simple broken wrist, are irreversible and cannot be fixed with current medical technologies. That is, there is very little we can currently do for those that sustained a bad spinal cord injury. Current studies using spinal cord stimulation have been trying to induce motor/sensory function for those affected by SCI. In this study, researchers were able to induce autonomic innervation (Flett et al., 2022). This type of activation could allow for better regulation of homeostasis and metabolic functions related to autonomic control in those impacted by SCI. Our nervous system is interesting with respect to its ability to be dynamic. We can strengthen connections or increase synaptic density, both of which likely cannot be done in an external device stimulating the spinal cord. As such, is there a limitation to spinal cord stimulation? Additionally, there is the notion of ‘use it or lose it’ for muscles/connections in our body. Under this notion, an individual is likely to lose these neural connections in addition to the muscle fibers they once had prior to the injury which could impact the potential effectiveness of spinal cord stimulation. At what point would it be too late to use spinal stimulation?
ReplyDeleteWith respect to spinal cord stimulation for those dealing with chronic pain, I question whether an individual would develop a type of dose dependency associated with stimulation.
Flett, S., Garcia, J., & Cowley, K. C. (2022). Spinal electrical stimulation to improve sympathetic autonomic functions needed for movement and exercise after spinal cord injury: a scoping clinical review. Journal of Neurophysiology, 128(3), 649–670. https://doi.org/10.1152/jn.00205.2022
Working for a spine surgeon this past year, I have seen several patients with spinal cord stimulators and for most of them, it was worked great for the past 5 years or so and the minority report it has not worked at all or they feel decreased effectiveness. Since implanting the stimulator is still considered surgery, how would you weigh getting a stimulator or getting a fusion? Regardless of the battery being rechargeable or non-rechargeable, there is a chance it will need to get replace in about 10 years or so, just like a getting another back surgery for the vertebral body above or below after fusion, or a joint replacement.
ReplyDeleteGoing off of Spencer's comment, I have read that there is potential for spinal cord stimulation to increase brain plasticity and locomotive function for stroke patients as well (Choi et al., 2017). This study tested on mice that lumbar spinal cord stimulation with gait training increased functional recovery after a sham lesion. I definitely think there is some potential here for treatment of other diseases as well.
Choi, Y.-H., & Lee, S.-U. (2017). Enhancement of brain plasticity and recovery of locomotive function after lumbar spinal cord stimulation in combination with gait training with partial weight support in rats with cerebral ischemia. Brain Research, 1662, 31–38. https://doi.org/10.1016/j.brainres.2017.02.017
To answer your question Nica on choosing between a Spinal cord stimulator or a fusion I think there is a lot to consider. Are there some identifiable structural concerns or is it strictly pain? If the patient only has pain, in my opinion, you recommend starting with the SCS. The SCS has a trial run which ensures that it will reduce or make manageable the patient’s pain. If unsuccessful you simply remove the leads and try another treatment. Fusion is a permanent procedure that will also limit the flexibility of the spine.
ReplyDeleteReal interesting post, I have heard of these sort of surgical procedures in the past but didn't even realize that they are actually being done on people already. I noticed you mentioned that mechanical issues could worsen which is exactly what i thought about as well. For example, your knee keeps 'clicking' and is super painful to put pressure on, so we just send a signal over to the sensor and our pain is essentially gone. The mechanical issue of the knee will still remain and perhaps lead to much worse problems, tears, swelling, joint on joint rubbing, etc. So aside from mechanical issues one may face, I think that this surgical remedy is a great option for those who experience chronic pain. It also seems like a reliable and safe procedure. An article that I saw ran several studies on spinal cord stimulator infection rates and the results turned out that the rates of infection are on the same level as other types of surgical procedures. There wasn't a noticeable high risk for negative outcomes which is good to hear.
ReplyDeleteSource:
Hoelzer, B. C., Bendel, M. A., Deer, T. R., Eldrige, J. S., Walega, D. R., Wang, Z., ... & Choi, D. Y. (2017). Spinal cord stimulator implant infection rates and risk factors: a multicenter retrospective study. Neuromodulation: Technology at the Neural Interface, 20(6), 558-562.
This was fascinating. What we can do with technology nowadays, and to think it's only the beginning! This here seems to be too good to be true. I did read an article about the limitations of spinal cord stimulators (SPS), and it's as you claim. The associated risk of surgery appears to be relatively smooth and safe. I did notice a trend in SCS complaints and cons, and that was lead migration; there are a significant number of patients who are unable to fully benefit and manage their pain due to lead connection failure. Again, it is not the end of the world, and removing it is simple and safe. I'm honestly surprised that this treatment and technology aren't used more frequently, given the ongoing opioid epidemic. Is this procedure prohibitively expensive? Is it possible for this device to be hacked or affected in such a way that it causes damage to the surrounding area? According to what I've read, it can irritate the skin and MRIs are incompatible with the device and should be turned off if this scan is required.
ReplyDeleteShim JH. Limitations of spinal cord stimulation for pain management - PMC [Online]. PubMed Central (PMC): 2015. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4524928/