Cylindrical vs Paddle Leads in Spinal Cord Stimulation for the Long-term Treatment of Chronic Pain: A Systematic Review and Meta-analysis.

OBJECTIVES

This systematic review compares the long-term efficacy of cylindrical-lead spinal cord stimulation (CL-SCS) vs paddle-lead spinal cord stimulation (Paddle-SCS) for chronic pain management.

MATERIALS AND METHODS

We included prospective and retrospective studies with at least ten patients reporting on the efficacy of either lead type. Primary outcomes were pain score reduction (measured by the visual analog scale [VAS] and numeric rating scale [NRS]) and 50% pain relief after at least 12 months. Secondary outcomes included functional disability and complications, such as lead migration and infection rates. Meta-analyses compared effect sizes, while meta-regression and subgroup analyses addressed heterogeneity.

RESULTS

A total of 96 studies, comprising 7726 patients, met the inclusion criteria. Paddle-SCS demonstrated superior pain reduction, with a standardized mean difference (SMD) of 5.37 (95% CI [5.35, 5.38]) compared with CL-SCS, which had an SMD of 4.09 (95% CI [4.08, 4.10]) on the VAS. However, CL-SCS outperformed Paddle-SCS on the NRS, with SMDs of 4.39 vs 2.35, respectively. For 50% pain relief, Paddle-SCS had a success rate of 41.4%, as opposed to 35.4% for CL-SCS. Paddle-SCS showed a lower migration rate (4.3% vs 7.2% for CL-SCS) but higher infection rates (5.0% vs 3.3%).

CONCLUSIONS

Paddle-SCS offers superior pain reduction (as measured by the VAS) and a lower migration rate, but a higher infection risk compared with CL-SCS. CL-SCS showed better outcomes as measured by the NRS. The choice between Paddle-SCS and CL-SCS should be individualized according to patient-specific factors and treatment goals. Further research with rigorous study designs is needed to provide clearer comparisons between these interventions.