Chronic lumbosacral radiculopathy is a frequently encountered clinical condition characterized by pain radiating from the lower back into the lower extremities, often accompanied by sensory, motor, or reflex deficits along the affected nerve root distribution. One of the most common etiologies of lumbosacral radiculopathy is posterolateral intervertebral disc herniation, which exerts mechanical compression on the adjacent nerve roots and provokes a cascade of inflammatory responses in the surrounding neural tissue . This condition not only affects the physical functionality of patients but also significantly diminishes their quality of life, leading to psychological stress and economic burden due to reduced productivity and long-term healthcare needs.

Traditional fluoroscopy-guided techniques, though effective, involve radiation exposure and may be limited in resource-constrained settings. In contrast, ultrasound-guided (USG) caudal epidural steroid injections offer a radiation-free, real-time, and cost-effective alternative that allows direct visualization of the sacral hiatus, needle advancement, and drug dispersion. Despite increasing clinical use, there remains a relative paucity of high-quality evidence evaluating the effectiveness of USG-guided CESIs, particularly focusing on electrophysiological outcomes alongside clinical parameters.

Electrophysiological studies, including nerve conduction studies (NCS) and electromyography (EMG), offer objective tools to assess the functional integrity of the affected nerve roots. While pain and functional scales provide subjective evaluation, electrophysiological parameters serve as valuable biomarkers for nerve recovery and response to treatment. This observational study aims to investigate the effectiveness of a single-dose USG-guided caudal epidural steroid injection in patients with chronic lumbosacral radiculopathy secondary to posterolateral disc herniation. Specifically, the study evaluates the intervention’s impact on electrophysiological parameters, functional status, radicular symptoms, and pain intensity over a defined follow-up period. By integrating both objective and subjective outcome measures, this research seeks to contribute meaningful data to support the broader application of USG-guided CESIs as a safe, effective, and non-surgical treatment option for managing chronic lumbosacral radiculopathy.