Epidural interlaminar injections in severe degenerative lumbar spine: fluoroscopy should not be a luxury

To assess technical efficacy, accuracy, and safety of epidural (interlaminar) injections performed blindly in patients with a severely degenerated lumbar spine.

Over 12 consecutive months, 138 patients with a severe degenerative lumbar spine underwent epidural (interlaminar) injection as therapy for low back pain and neuralgia. Patients had already undergone a blind epidural infiltration with minimum or no pain reduction. The session was repeated in the angiography suite. Patients were placed in the lateral decubitus position. The injection was performed without image guidance by an anaesthesiologist; the target level was defined before the beginning of the procedure. Once air resistance loss was felt it was presumed that the needle was inside the epidural space. Verification of needle position was performed by injection of 1-3 mL of iodinated contrast medium under fluoroscopy in a lateral projection.

Correct needle position inside the epidural space was documented in 82/138 cases (59.4%); unexpected extraepidural location was seen in 56/138 cases (40.6%). Target level was reached in 96/138 cases (69.6%); in 42/138 cases (30.4%) the needle was positioned in a non-target level. In 5/138 (3.6%) cases, there was inadvertent intradural position of the needle. Image guidance was subsequently used for correct positioning of the needle, which was feasible in all cases.

Blind interlaminar epidural injections lack the accuracy of exact needle location that imaging guidance offers in approximately 40% of cases, when there is difficult spine anatomy and the initial epidural approach has failed to provide pain relief. Image guidance for interlaminar epidural injection ensures accurate needle placement, enhancing the safety and efficacy of the procedure.