INTRODUCTION

Spinal cord stimulation (SCS) is frequently used to treat chronic, intractable back, and leg pain. Implantation can be accomplished with percutaneous leads or paddle leads. Although there is an extensive literature on SCS, the long-term efficacy, particularly with paddle leads, remains poorly defined. Outcome measure choice is important when defining therapeutic efficacy for chronic pain. Numerical rating scales such as the NRS-11 remain the most common outcome measure in the literature, although they may not accurately correlate with quality of life improvements and overall satisfaction.

METHODS

We reviewed the medical records of patients with failed back surgery syndrome (FBSS) or complex regional pain syndrome (CRPS) implanted with SCS systems using paddle leads between 1997 and 2008 at the Cleveland Clinic with a minimum six-month follow-up. Patients were contacted to fill out a questionnaire evaluating outcomes with the NRS-11 as well as overall satisfaction.

RESULTS

A total of 35 eligible patients chose to participate. More than 50% of the patients with CRPS reported greater than 50% pain relief at a mean follow-up of 4.4 years. Approximately 30% of the FBSS patients reported a 50% or greater improvement at a mean follow-up of 3.8 years. However, 77.8% of patients with CRPS and 70.6% of patients with FBSS indicated that they would undergo SCS surgery again for the same outcome.

CONCLUSION

Patients with CRPS and FBSS have a high degree of satisfaction, indexed as willingness to undergo the same procedure again for the same outcome at a mean follow-up of approximately four years. The percentage of satisfaction with the SCS system is disproportionally greater than the percentage of patients reporting 50% pain relief, particularly among patients with FBSS. This suggests that the visual analog scale may not be the optimal measure to evaluate long-term outcomes in this patient population.