A COMPARATIVE STUDY TRANSFORAMINAL VERSUS INTERLAMINAR EPIDURAL STEROID INJECTION IN MANAGEMENT OF SYMPTOMATIC LUMBAR DISC HERNIATION.

 Background: Lumbar disc herniation is the 1 st most common cause of low backache with lower limb radiculopathy. A herniated disc fragment comes from the nucleus pulposus of the disc, when a fragment of nucleus herniates, it irritates and/or compresses the adjacent nerve root. This can cause the pain syndrome known as sciatica and, in severe cases, dysfunction of the nerve. Epidural steroid injections (ESIs) are a common treatment option for low back pain and leg pain. The goal of the injection is pain relief. ESIs are given by interlaminar and transforaminal approaches, the interlaminar (blinded) approach is considered capable of delivering the medication closest to the assumed site of pathology, but the transforaminal (fluoroscopy -guided) approach is considered the most target-specific modality requiring the smallest volume with high concentration to reach the primary site of pathology, so assumed to get better response.  Objective : To compare the effectiveness in short-term pain improvement and functional status between transforaminal and interlaminar epidural steroid injection techniques in management of lumbar disc herniation with radicular pain.  Patients and methods : One hundred thirty-two patients of both sexes with symptomatic lumbar disc herniation who had no improvement after a minimum of six weeks non-invasive treatment were enrolled in our study. Management was done by two types of Epidural Steroid Injection (ESIs): blinded interlaminar and fluoroscopy-guided transforaminal, so the patients were grouged into Transforaminal group (TFg =70 patients) and Interlaminar group (ILg =62 patients). The functional status and the severity of pain of patients in each group were evaluated separately before injection and after injection during six months follow-up period using Verbal Numerical Rating Scale (VNRS) and Oswestry Disability Index (ODI) scales. Comparism between these two groups was made according to VNRS and ODI scores values to determine how much response rate and surgical rate in each group.  Results : This study included 132 patients; 65 (49%) were male and 67 (51%) were female, aged from 22 to 80 years old (mean 51.9). Their groups: TFg was composed of 70 patients, while ILg contained 62 cases. The mean VNRS was 6.7 and 7.9 for TFg and ILg, mean ODI was 34.3, 35.2 for TFg and ILg respectively. The total response was 83.3% (110 cases) and in each group was (87.1% 61 patients) for TFg, and (79% 49 patients) for ILg, all of pespnded patients developed improvement after injection, they experienced more than 50% pain decrease and well-being, although TFg patients developed little bit better result than ILg in short and long term period, possibly due to more precised and specific-targeted pain generator (nerve root) by ESIs. The failure (surgical) rate was 16.6% (22 patients); 12.8% (9 patinets) for TFg, and 21% (13 patients) for ILg, those patients rated their condition as bad.  Conclusion : The epidural steroid injections gives short term or long term pain relief from symptomatic lumbar disc herniation and specifically transforaminal epidural steroid injections resulted in a more short term pain improvement and fewer long term surgical rates than interlaminar epidural steroid injection, mostly due to ability of targeting the specific area (nerve root) generating pain so the patient can experience much more benefit from the injection.