226. Surgical treatment of refractory low back pain using implanted BurstDR spinal cord stimulation (SCS) in a cohort of patients without options for corrective surgery: findings and results from the DISTINCT study, a prospective randomized multi-center controlled trial

BACKGROUND CONTEXT Low back pain (LBP) is a highly prevalent and costly condition affecting millions of people worldwide across all sociodemographic classes. Globally, it is the number one cause of disability. Those with an identifiable anatomic pain generator may receive back surgery and achieve relief, but many are not candidates as they lack an identifiable surgically corrective pathology. Standard nonoperative strategies include physiotherapy, oral analgesics and image-guided injections; however, these may not provide durable relief. Spinal cord stimulation is sometimes used to treat these patients but level I evidence to support the use of spinal cord stimulation for these patients is sparse. We present results from DISTINCT (NCT04479787), the largest RCT to date, comparing dorsal column passive recharge burst SCS to conventional medical management (CMM) in this patient population. PURPOSE To evaluate the efficacy of passive recharge burst SCS, when compared to CMM, in improving pain and pain-related physical function in patients suffering from chronic, refractory predominately axial low back pain, who have not had lumbar spine surgery and for whom corrective surgery is not an option. STUDY DESIGN/SETTING This is a prospective, multicenter, randomized, controlled clinical study with an optional crossover component (after 6 months). Subjects will be followed in-clinic at 1,3, 6, 9, 12, 18 and 24 months. Primary and secondary endpoints are assessed at the 6-month follow-up visit. PATIENT SAMPLE The study completed enrollment (n=270) in September 2021. An independent board-certified spine surgeon reviewed each case including MRI and confirmed a lack of suitable corrective surgical options. OUTCOME MEASURES Primary and secondary endpoints are designed to assess improvements in low back pain intensity (NRS), low back pain-related disability (ODI), pain catastrophizing (PCS), and patient global impression of change (PGIC). METHODS A responder analysis was used to compare proportions of subjects in each arm who experience clinically meaningful pain relief, decreased disability, decreased emotional distress and high satisfaction. Responders were defined as having a 50% reduction on NRS, 13 percentage points or greater decrease on ODI (MCID) or a categorical change to minimal disability, 40% decrease on PCS (MCID) or a categorical change from clinically catastrophizing, a definite or considerable improvement in a subject's painful condition on PGIC. RESULTS The average age was 58 years; 30% were under 50 years. Subjects experienced chronic pain for an average of 12.3 years; 50% over 10 years. Multiple previous types of treatments had failed (average = 3.5); 86% (n=233) failed an average of 4.9 injections, 41% (n=110) failed an average 2.9 ablation procedures. 107 were randomized to CMM with an optional cross-over at 6 months. 162 were randomized to SCS therapy; 87% reported at least 50% pain relief after the trial period and were eligible to receive an implanted device. The average NRS for low back pain decreased from 7.7 to 2.5. Post-trial, 125 percutaneous and 50 paddle leads were implanted; 96% were placed between T7 and T9. SCS subjects reported superior meaningful reductions in pain intensity and low back pain-related disability compared to CMM subjects. Pain-related emotional distress was also improved in the SCS treatment arm compared to CMM. CONCLUSIONS DISTINCT study results demonstrate that passive recharge burst is superior to conventional medical management for patients suffering from severe, debilitating low back pain that cannot be addressed through corrective surgical intervention. Primary and secondary endpoints demonstrate dramatic improvements in pain, function and pain-related emotional distress. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs. Low back pain (LBP) is a highly prevalent and costly condition affecting millions of people worldwide across all sociodemographic classes. Globally, it is the number one cause of disability. Those with an identifiable anatomic pain generator may receive back surgery and achieve relief, but many are not candidates as they lack an identifiable surgically corrective pathology. Standard nonoperative strategies include physiotherapy, oral analgesics and image-guided injections; however, these may not provide durable relief. Spinal cord stimulation is sometimes used to treat these patients but level I evidence to support the use of spinal cord stimulation for these patients is sparse. We present results from DISTINCT (NCT04479787), the largest RCT to date, comparing dorsal column passive recharge burst SCS to conventional medical management (CMM) in this patient population. To evaluate the efficacy of passive recharge burst SCS, when compared to CMM, in improving pain and pain-related physical function in patients suffering from chronic, refractory predominately axial low back pain, who have not had lumbar spine surgery and for whom corrective surgery is not an option. This is a prospective, multicenter, randomized, controlled clinical study with an optional crossover component (after 6 months). Subjects will be followed in-clinic at 1,3, 6, 9, 12, 18 and 24 months. Primary and secondary endpoints are assessed at the 6-month follow-up visit. The study completed enrollment (n=270) in September 2021. An independent board-certified spine surgeon reviewed each case including MRI and confirmed a lack of suitable corrective surgical options. Primary and secondary endpoints are designed to assess improvements in low back pain intensity (NRS), low back pain-related disability (ODI), pain catastrophizing (PCS), and patient global impression of change (PGIC). A responder analysis was used to compare proportions of subjects in each arm who experience clinically meaningful pain relief, decreased disability, decreased emotional distress and high satisfaction. Responders were defined as having a 50% reduction on NRS, 13 percentage points or greater decrease on ODI (MCID) or a categorical change to minimal disability, 40% decrease on PCS (MCID) or a categorical change from clinically catastrophizing, a definite or considerable improvement in a subject's painful condition on PGIC. The average age was 58 years; 30% were under 50 years. Subjects experienced chronic pain for an average of 12.3 years; 50% over 10 years. Multiple previous types of treatments had failed (average = 3.5); 86% (n=233) failed an average of 4.9 injections, 41% (n=110) failed an average 2.9 ablation procedures. 107 were randomized to CMM with an optional cross-over at 6 months. 162 were randomized to SCS therapy; 87% reported at least 50% pain relief after the trial period and were eligible to receive an implanted device. The average NRS for low back pain decreased from 7.7 to 2.5. Post-trial, 125 percutaneous and 50 paddle leads were implanted; 96% were placed between T7 and T9. SCS subjects reported superior meaningful reductions in pain intensity and low back pain-related disability compared to CMM subjects. Pain-related emotional distress was also improved in the SCS treatment arm compared to CMM. DISTINCT study results demonstrate that passive recharge burst is superior to conventional medical management for patients suffering from severe, debilitating low back pain that cannot be addressed through corrective surgical intervention. Primary and secondary endpoints demonstrate dramatic improvements in pain, function and pain-related emotional distress.