The Association Between Morphometric Features of Neural Foramen and Intervertebral Disc and Treatment Success of Lumbar Transforaminal Epidural Steroid Injection: An Observational Study

Abstract

To investigate the impact of morphometric characteristics of neural foramen (NF) and intervertebral disc (ID) on magnetic resonance imaging (MRI) to the treatment outcomes after transforaminal epidural steroid injection (TFESI). Few clinical and radiological features are suggested predicting treatment success after epidural steroid injection. However, the impact of morphometric characteristics of the relevant NF to the response to TFESI is unknown. Material and Methods: This study was carried out prospectively with the participation of 45 patients who were treated with single level TFESI to L5 nerve root. Pain intensity, disability, and depression levels were assessed at baseline, 3rd week and 3rd month. The morphometrics of the relevant NF and ID were evaluated on sagittal MRI scans and compared between patients who responded and did not respond to the treatment. Results: The interrater reliability of all morphometric measurements of NF and ID performed by 2 physicians were high or excellent. Pain, depression, and disability scores were improved significantly at 3rd month compared to baseline. No statistically significant difference was found between responders and non-responders regarding morphometric evaluation (p>0.05). Conclusion: The results of the present study indicate that MRI based morphometric parameters like disc height, pedicle length, minimum and maximum foraminal width, foraminal crosssectional area (CSA), and nerve root CSA have no effect on the efficacy of TFESI.