Traditional Safe Triangle Approach Versus Kambin's Triangle Approach: Does Approach Really Matter in Transforaminal Epidural Steroid Injection (TFESI) for Lumbar Disc Herniation?

Background: Lumbar disc herniation (LDH) is one of the primary causes of back and leg pain affecting today's working population and is a major contributor to sickness absenteeism, creating a substantial socio-economic burden. Low back pain is one of the leading causes of physical disability in both old and younger age groups. Low back pain has a point prevalence of 12%, a year-on-year prevalence of 38%, and a lifetime prevalence of 40%. The aging population leads to a rising number of individuals affected by lower back pain. The study aims to compare the outcome of percutaneous transformational epidural steroid injection (TFESI) for LDH using the traditional safe triangle approach versus Kambin's triangle approach. Materials and methods: A retrospective cohort hospital-based observational study was conducted among a total of 90 patients who had underwent percutaneous epidural steroid injection using the traditional safe triangle approach versus Kambin's triangle approach for LDH. Patients were identified through electronic medical record (EMR) documentation submitted to the Department of Orthopaedics, R.L. Jalappa Hospital Centre, during the period of May 2022 to May 2023.

Results: The majority of patients in Group A belonged to the 61-65 years and in Group B to the 71-75 years, respectively. The overall success rate of the procedure was higher in the safe triangle approach, and there was an association found between the type of procedure and the successful rate. There was no statistically significant difference between the two approaches, namely, traditional safety triangle approach and Kambin's triangle approach, in terms of Numerical Rating Scale (NRS) score and Oswestry Disability Index (ODI) score at pre-injection and at one month and three months post-injection.  Conclusion: The Kambin's triangle approach is just as effective for the interim outcome as the subpedicular approach and provides significant advantages. The Kambin's triangle approach may be used as an alternative to TFESI in situations where needle tip placement in the anterior epidural is challenging.