The use of magnetic resonance imaging to predict the clinical outcome of non-surgical treatment for lumbar interverterbal disc herniation

Objective: We wanted to investigate the relationship between the magnetic resonance (MR) findings and the clinical outcome after treatment with non-surgical transforaminal epidural steroid injections (ESI) for lumbar herniated intervertebral disc (HIVD) patients. Materials and Methods: Transforaminal ESI were performed in 91 patients (50 males and 41 females, age range: 13-78 yrs) because of lumbosacral HIVD from March 2001 to August 2002. Sixty eight patients whose MRIs and clinical followups were available were included in this study. The medical charts were retrospectively reviewed and the patients were divided into two groups; the successful (responders, n = 41) and unsatisfactory (non-responders, n = 27) outcome groups. A successful outcome required a patient satisfaction score greater than two and a pain reduction score greater than 50%. The MR findings were retrospectively analyzed and compared between the two groups with regard to the type (protrusion, extrusion or sequestration), hydration (the T2 signal intensity), location (central, right/left central, subarticular, foraminal or extraforaminal), and size (volume) of the HIVID, the grade of nerve root compression (grade 1 abutment, 2 displacement and 3 entrapment), and an association with spinal stenosis. Results: There was no significant difference between the responders and nonresponders in terms of the type, hydration and size of the HIVID, or an association with spinal stenosis (p > 0.05). However, the location of the HIlVD and the grade of nerve root compression were different between the two groups (p < 0.05). Conclusion: MRI could play an important role in predicting the clinical outcome of non-surgical transforaminal ESI treatment for patients with lumbar HIVD.