The Effect of Needle Insertion Angle on Contrast Distribution and Treatment Outcomes in S1 Transforaminal Epidural Steroid Injections

Nerve compression due to lumbar disc herniation (lumbosacral radiculopathy) is a condition characterized by pain in the lower back and legs and restricted lumbar joint movement due to the compression of nerves emerging from the lumbar spine caused by the protrusion of the intervertebral disc. Back pain negatively impacts patients' quality of life and emotional well-being. Treatment approaches aim to alleviate pain, improve joint mobility, and restore functionality through the use of pain-relief medications (topical or oral), physical therapy methods, and rehabilitation programs that include exercises for range of motion, stretching, and strengthening. When these approaches prove insufficient, interventional procedures (injection therapy) or surgical interventions come to the forefront.

One of the proven interventional treatment methods for herniated disc disease is the transforaminal epidural steroid injection (TFESE), which involves the injection of cortisone around the compressed nerve due to the herniation and is frequently performed in our clinic. Transforaminal injections require imaging guidance and the use of contrast media to enhance the safety and effectiveness of the procedure. To visualize the S1 foramen, needle entry is performed using various angles under fluoroscopy guidance. This study will investigate the effect of the needle entry angle on the spread and pattern of contrast media, complications, and treatment outcomes in fluoroscopy-guided S1 transforaminal epidural steroid injections. The research aims to determine whether the needle entry angle influences the pattern of contrast spread and the treatment outcomes in S1 TFESE.

Based on the findings of this study, the goal is to refine the procedure for patients requiring injections at this level in the future, optimizing the technique and clinical outcomes. This will provide essential insights to practitioners, maximize the benefits for the patient group undergoing the procedure, and make a significant contribution to medical science. Detailed information regarding the planned injection therapy by your algology specialist will be provided, and written and verbal consent will be obtained through the "Epidural Steroid Injection Consent Form." Various scales and questionnaires will be administered at specific intervals-prior to the procedure, 1 hour after, 3 weeks after, and 3 months after-to evaluate pain levels, treatment response, and the impact on daily activities. The content of these evaluations will be explained in detail by your physician.

Temporary side effects related to the injection may include increased pain at the injection site, low blood pressure, dizziness, fainting, and allergic reactions, all of which can be managed with appropriate treatment. Although rare, severe side effects such as nerve damage, spinal cord injury, or stroke have been reported in some cases. However, adherence to the guidelines outlined in treatment protocols and the performance of the procedure by adequately trained and experienced physicians significantly reduce the likelihood of these serious side effects. This injection will be performed by an algology specialist with at least 10 years of experience in this field. All necessary precautions will be taken against potential side effects, and the performing team will provide immediate medical intervention in case of complications.

Approximately 66 volunteers will participate in this study, with each follow-up evaluation expected to take about 15 minutes. The identities of participants will remain confidential, and they have the right to withdraw from the study at any time by notifying the researchers. If deemed necessary by the researchers, participants may also be excluded from the study. If a participant declines to participate or is excluded from the study, their treatment will not be interrupted. Participants will not bear any financial responsibility for research-related expenses, and no additional travel costs will be incurred as evaluations will coincide with regular clinic visits.