Retrospective analysis of cervical transforaminal versus interlaminar epidural steroid injections.

Background: Several studies have compared outcomes from lumbar epidural steroid injections (ESIs) based upon technique (transforaminal (TF) vs interlaminar (IL) vs caudal). However, little on this topic has been reported in the cervical spine, and results have been conflicting.

Purpose: To compare success rates of fluoroscopically-guided cervical TFESIs vs ILESIs.

Study Design/setting: Retrospective, observational, in vivo study of consecutive patients at outpatient Physical Medicine & Rehabilitation clinics at a single academic spine center.

Patient Sample: Consecutive patients who received a cervical TF or IL ESI between January 2010 and October 2018.

Outcome Measures: NRS pain scores within 60 days of the ESI.

Methods: Current procedural terminology (CPT) codes were used to search all consecutive patients at a single outpatient academic spine center who received a cervical TF or IL ESI between January 2010 October 2018. All patients with pre and post injection NRS pain scores within 60 days of the injection were included in the analysis.

Results: A total of 178 ​TF and 185 ILESIs were analyzed. Success was defined as ≥ 50% improvement in NRS pain score. 52% [95% CI: 47 - 57%] of all patients receiving a cervical ESI achieved a successful outcome. There was a strong trend towards better results in the ILESI group with 59% [95% CI: 52 - 66%] of patients achieving at least 50% pain relief compared to 46% [95% CI: 39 - 53%] in the TF group. A higher proportion of patients in the IL group obtained at least 80% pain relief (37% [95% CI: 30 - 44%]) compared to those in the TF group (17% [95% CI: 11 - 23%]). Post-procedure median NRS pain scores, and improvement in median NRS pain scores were better in the ILESI group compared to the TFESI group (p<0.001).

Conclusion: This retrospective study demonstrated better results in the cervical ILESI group compared to the cervical TFESI group.