Dorsal Column Spinal Cord Stimulation SCS: A Clinical Perspective

By Ali Alhimiri, MD

Spinal Cord Stimulation (SCS) has significant complications and costs thousands of dollars more than a simpler Transcutaneous Electrical Nerve Stimulation (TENS) unit, despite both utilizing the same mechanism of action.

Dorsal column spinal cord stimulation (SCS) involves the insertion of electrodes into the epidural space of the spine—cervical, thoracic, or lumbar—under fluoroscopic guidance. This procedure, usually performed by an anesthesiologist, consists of two stages: an initial experimental trial and a definitive implantation if the trial is deemed successful. The technique applies electrical stimulation to the posterior column of the spinal cord with varying intensity and duration, theoretically acting as a distraction from pain signals originating from other parts of the body. The premise is that this overstimulation leads to desensitization and reduced pain perception.

Melzack, R., & Wall, P. D. (1965) Pain mechanisms: this seminal paper introduces the gate control theory of pain, which is the theoretical foundation for spinal cord stimulation and other sensory overstimulation modalities such as TENS unit. It explains how non-painful stimuli can block the transmission of pain signals to the brain, which SCS utilizes by applying electrical stimulation to the spinal cord through the skin in SCS or over the skin as in TENS units.

SCS is often cited in the literature as a treatment for conditions such as failed back syndrome, intractable pain following spinal cord injury, phantom limb pain, herpetic neuralgia, and complex regional pain syndrome. However, the procedure is not without risks as we listed below.

Moreover, SCS can give patients a false sense of control over their pain by allowing them to adjust the level of stimulation. While this might seem empowering, it does not address the underlying issues causing the pain and may lead to a dependency on the device. The cost of the SCS device is also a significant consideration, with prices in tens of thousands, compared to a TENS unit, which typically costs around $40. This vast difference in cost raises further questions about the value of SCS, especially when more straightforward, less expensive alternatives are available.

The use of SCS is associated with a range of potential complications, as documented in the literature:

1. Infection: A common complication in 2-10% of cases, ranging from superficial wound infections to deep infections requiring device removal.Lead Migration: Leads can shift from their original position, leading to loss of pain relief, with migration rates reported as high as 20%.Lead Fracture: Mechanical stress can cause lead breakage, necessitating surgical revision.
2. Dural Puncture and Cerebrospinal Fluid (CSF) Leak: Accidental puncture of the dura during lead placement can result in CSF leaks, leading to headaches and other complications.
3. Hardware Malfunction: Issues like battery failure or pulse generator malfunction can occur, requiring further intervention.
4. Pain at the Implant Site: Some patients experience pain at the pulse generator or lead site.
5. Seroma or Hematoma Formation: Fluid (seroma) or blood (hematoma) can accumulate around the implant site, potentially requiring drainage or surgery.
6. Neurological Damage: Rarely, there is a risk of neurological injury during lead placement, potentially worsening neurological symptoms.
7. Allergic Reactions: Some patients may develop allergic reactions to the materials used in the SCS device.
8. Epidural Hematoma: A rare but serious complication where bleeding in the epidural space can lead to spinal cord compression.
9. Loss of Efficacy Over Time: SCS may become less effective, often due to lead migration or patient adaptation to the stimulation.
10. Postoperative Hemorrhage: Bleeding after surgery can lead to complications such as increased pain or the need for reoperation.
11. Visceral or Motor Stimulation: Sometimes, SCS may inadvertently stimulate visceral organs or motor pathways, causing uncomfortable sensations or movements.
12. Respiratory Issues: Rarely, stimulation at certain spinal levels can interfere with respiratory function, especially if the leads are placed in the cervical region.
13. Psychological Effects: Some patients may experience psychological impacts, including anxiety, depression, or disappointment if the device fails to provide relief.

Given the extensive nature of the SCS procedure, its associated risks, costs, and the potential for giving patients a misleading sense of control, I am skeptical of its true benefit for managing conditions such as complex regional pain syndrome (CRPS). In cases like these, more straightforward and less invasive methods—such as sensory overstimulation, desensitization, TENS, or acupuncture—are based on similar theoretical principles and carry fewer potential side effects at a fraction of the cost.

Therefore, dorsal column spinal cord stimulation is not warranted in this context. The procedure’s risks, complexities, and high costs do not justify its use when alternative, less invasive, and significantly more affordable techniques are available and likely to provide similar outcomes.

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