What is the efficacy of spinal cord stimulation (SCS)?

From the Guidelines

Spinal cord stimulation is a highly effective treatment for certain chronic pain conditions, including cancer-related pain, with significant pain reduction in well-selected patients, as supported by the most recent evidence from 2025 1. The effectiveness of spinal cord stimulation (SCS) has been established for various chronic pain conditions, including failed back surgery syndrome, complex regional pain syndrome, and cancer-related pain.

• The therapy involves implanting electrodes near the spinal cord that deliver mild electrical pulses to interrupt pain signals.
• Traditional SCS uses low-frequency stimulation, while newer techniques include high-frequency, burst stimulation, and dorsal root ganglion stimulation, which may be more effective for specific pain patterns.
• The procedure typically begins with a trial period using temporary leads before permanent implantation.
• Success depends heavily on proper patient selection, with best results seen in those with neuropathic pain who have failed conservative treatments.
• According to the 2018 ESMO clinical practice guidelines, SCS is recommended for cancer-related pain, especially if the cancer is slow growing and pain is difficult to control with pharmacological options 1.
• The most recent evidence from 2025 suggests that SCS may provide significant pain relief in specific cases of moderate-to-severe refractory mechanical or visceral pain 1.
• Side effects are generally mild and include lead migration, infection, and hardware malfunction.
• SCS effectiveness tends to diminish somewhat over time, with approximately 60% of patients reporting continued significant pain relief at 5 years.
• The mechanism involves both direct inhibition of pain transmission in the dorsal horn and modulation of neurotransmitter release, providing a non-opioid alternative for long-term pain management.

From the Research

Effectiveness of Spinal Cord Stimulation

The effectiveness of spinal cord stimulation (SCS) for treating chronic pain has been studied in various research papers.

• SCS is thought to relieve chronic intractable pain by stimulating nerve fibers in the spinal cord, which may inhibit the conduction of pain signals to the brain 2.
• The sympatholytic effect of SCS is considered responsible for its effectiveness in peripheral ischemia, complex regional pain syndrome, failed back surgery syndrome, phantom pain, diabetic neuropathy, and postherpetic neuralgia 2.
• Studies have shown that SCS can be an effective treatment for certain types of chronic pain, including failed back surgery syndrome and complex regional pain syndrome type I 3.
• A review of SCS found that it is a safe and effective treatment for a variety of chronic pain conditions, with potential mechanisms of action including the inhibition of pain signals and the release of neurotransmitters 4.
• A systematic review and case series study found that SCS was effective in treating pain from different etiologies, with response rates of 55.56% in the failed back surgery syndrome group and 76.92% in the naive group 5.
• Another study discussed the evidence and theory for mechanisms of action of SCS in chronic pain, highlighting the need for further research to understand the pathways recruited when patterned electric pulses are applied to the epidural space 6.

Conditions Treated with Spinal Cord Stimulation

SCS has been used to treat a variety of chronic pain conditions, including:

• Failed back surgery syndrome 2, 3, 5
• Complex regional pain syndrome type I 3
• Peripheral ischemia 2
• Phantom pain 2
• Diabetic neuropathy 2
• Postherpetic neuralgia 2
• Neuropathic pain 5
• Chronic back pain ineligible for surgical intervention 5
• Oncological pain (although the effectiveness and safety of SCS for cancer-related pain has not yet been adequately established) 5

Mechanisms of Action

The exact mechanism of action of SCS is poorly understood, but it is thought to involve:

• The inhibition of pain signals to the brain 2
• The release of neurotransmitters 4
• The sympatholytic effect, which is considered responsible for the effectiveness of SCS in certain conditions 2
• The recruitment of specific pathways in the epidural space, although further research is needed to understand these pathways 6