Dural Sac Cross-Sectional Area Does Not Correlate with Efficacy of Percutaneous Adhesiolysis in Single Level Lumbar Spinal Stenosis

Abstract

Background: Spinal stenosis is a narrowing of the spinal canal, which causes mechanical compression of spinal nerve roots. The compression of these nerve roots can cause low back pain and/or leg pain, as well as neurogenic claudication. Lumbar epidural steroid injections have commonly been used in patients with lumbar spinal stenosis (LSS). In cases that are refractory to epidural steroid injections, percutaneous epidural adhesiolysis has been used. Objective: The aim of our study is to determine the relationship between the severity of spinal stenosis and the participants’ response to adhesiolysis, and to evaluate the mid-term effectiveness of adhesiolysis. Study Design: A prospective observational study. Methods: Sixty-six patients with degenerative LSS were enrolled in this prospective study. All participants underwent lumbar spine magnetic resonance imaging (MRI). The cross-sectional area of the dural sac was measured on the transverse angled sections through the central part of the disc on conventional MR images. All percutaneous adhesiolyses were performed in the operating room. One hour following the procedure, 6 mL of 8% sodium chloride solution was infused during 30 minutes in the recovery room while the patient underwent monitoring. Outcome measures were obtained using the 5-point patient satisfaction scale at 2 weeks and 6 months post-treatment. To evaluate outcome predictors, we divided the participants into 2 groups according to their response to treatment. Limitations: Secondary outcomes were not measured and the study did not include a long-term follow-up period. Results: Improvement (including reports of slightly improved, much improved, and no pain) was observed in 49 participants (74.2%) at 2 weeks and 45 participants (66.7%) at 6 months after the procedure. The dural sac cross-sectional area (DSCSA) did not differ between participants who reported improvement and those who did not. There was no statistically significant correlation between pain relief and DSCSA, age, or participant sex. Conclusion: Percutaneous adhesiolysis was shown to be effective for the treatment of LSS, with mid-term result, without affecting DSCSA. Key words: Low back pain, lumbar spinal stenosis, failed back surgery syndrome, dural sac, interventional techniques, epidural injection, percutaneous adhesiolysis.