NEW ORLEANS—The use of spinal cord stimulation (SCS) therapy for the treatment of chronic pain has seen a significant uptick in recent years. Despite increased utilization and the existence of general indications, the ability to predict which patients will respond to SCS therapy is one of the main challenges in neuromodulation. A groundbreaking retrospective, single-center, observational study presented at the 2023 Annual Pain Medicine Meeting of the American Society of Regional
FEBRUARY 2, 2024
High Levels of Kinesiophobia Associated With Nonresponse to SCS Therapy
NEW ORLEANS—The use of spinal cord stimulation (SCS) therapy for the treatment of chronic pain has seen a significant uptick in recent years. Despite increased utilization and the existence of general indications, the ability to predict which patients will respond to SCS therapy is one of the main challenges in neuromodulation. A groundbreaking retrospective, single-center, observational study presented at the 2023 Annual Pain Medicine Meeting of the American Society of Regional Anesthesia and Pain Medicine has shed light on key variables that may help distinguish patients who are less likely to benefit from high-frequency (10-kHz) SCS.
The study found high levels of kinesiophobia in nonresponders to high-frequency SCS therapy (Pain Pract 2023 Dec 11. doi:10.1111/papr.13328). Kinesiophobia is defined as “an excessive and irrational fear to carry out physical movements due to the feeling of vulnerability, pain and injury.”
“This is the first study in the neuromodulation literature to report an association between high levels of kinesiophobia preoperatively and nonresponders to high-frequency SCS,” said Vinny Francio, MD, a lead study author and fellow in interventional pain management at the University of Kansas Medical Center, in Kansas City.
The study, comprising 237 patients with chronic low back pain who underwent 10-kHz SCS implantation, aimed to identify predictors of nonresponse by dividing participants into responder and nonresponder groups. Nonresponders were defined as those who had less than 50% self-reported pain relief at 12 months of follow-up compared with baseline, while responders had 50% or more improvement.
Results revealed that 67.51% of patients were responders, while 32.49% were nonresponders. In addition to high levels of preoperative kinesiophobia, high self-perceived disability and clinically relevant pain catastrophizing at baseline were identified as statistically significant factors in the nonresponder group compared with responders, suggesting that it may be appropriate to preoperatively screen for kinesiophobia and pain catastrophizing at baseline to identify patients who are less likely to respond to SCS.
“For those that might not know, kinesiophobia is a component of the fear avoidance behavior model, which refers to when patients have fear of movement or physical activity,” Francio said. “That may translate to poor outcomes, and our findings corroborate the perspective of the fear avoidance model.”
Variables deemed potentially relevant did not show statistical significance in predicting SCS response, including age, sex, history of spinal surgery, diabetes, alcohol use, tobacco use, psychiatric illness and opioid utilization at baseline.
Commenting on the study, Peter Staats, MD, the chief medical officer of National Spine & Pain Centers and founder of the Division of Pain Medicine at the Johns Hopkins University School of Medicine, in Baltimore, said: “While spinal cord stimulation is one of the most effective strategies we have in managing back pain, the therapy, unfortunately, does not work for everyone. This was an important single-center study teasing out the predictive factors of patients who may not benefit from SCS.
“More importantly, it begins the discussion of how to optimize a patient with kinesiophobia, pain catastrophizing and greater disability prior to consideration of an SCS implant,” said Staats, a Pain Medicine News editorial advisory board member. “These factors are extraordinarily important for the treating physician as well as those interested in clinical study design. Careful attention to these factors will lead to improved long-term outcomes for patients, and for the medical device industry in designing clinical trials.”
In light of these results, the researchers suggest that preoperative screening for kinesiophobia, high disability and pain catastrophizing may aid in identifying patients less likely to respond to SCS. The authors also recommend the implementation of pre-rehabilitation programs with pain neuroscience education for patients exhibiting these modifiable risk factors. By addressing these psychological and behavioral factors prior to SCS therapy, healthcare providers can improve patient satisfaction and patient selection while enhancing the overall success of neuromodulation outcomes.
—Meg Barbor, MPH
Francio reported research funding from Nevro (an investigator-initiated study grant). Staats reported serving as a consultant to Biotronik and Saluda/Medtronic; neither of these spinal cord stimulator companies were involved in the study.
