Needle Trajectory Influences Foraminal Contrast Distribution and Pain Reduction Following Paramedian Cervical...

Area of Science:

• Pain Management
• Interventional Pain Procedures
• Spinal Injections

Background:

• Paramedian cervical interlaminar epidural steroid injection (CESI) is a common treatment for cervical radicular pain.
• Its effectiveness may depend on contrast distribution, which may not fully represent drug delivery.

Purpose of the Study:

• To investigate the association between needle trajectory, contrast spread patterns, and short-term pain reduction after paramedian cervical interlaminar CESI.

Main Methods:

• Retrospective study of 109 patients undergoing paramedian cervical interlaminar CESI.
• Needle trajectory (inward vs. outward) and anteroposterior (AP) contrast spread were assessed.
• Pain reduction was measured using the numeric rating scale (NRS) at baseline and 2 weeks post-procedure.

Main Results:

• Outward needle trajectory was linked to significantly greater Grade 2 AP contrast spread (69.8% vs. 8.9%, p < 0.001).
• Patients with outward trajectories experienced greater NRS reduction (1.25 points, p < 0.001) compared to those with inward trajectories.
• Multivariable analysis confirmed needle trajectory, but not AP contrast spread grade, as independently associated with pain reduction.

Conclusions:

• Needle trajectory is a significant factor influencing contrast distribution and short-term pain relief in paramedian cervical interlaminar CESI.
• An outward-directed needle trajectory is associated with enhanced foraminal/periradicular contrast spread and superior pain reduction.
• Procedural needle trajectory may be a key factor for optimizing clinical outcomes in cervical epidural steroid injections.