Contrast flow selectivity during transforaminal lumbosacral epidural steroid injections.

BACKGROUND: Lumbosacral transforaminal epidural steroid injections (LS-TFESIs) are an accepted procedure used in the comprehensive, conservative care for lumbar disc pathology and/or spinal stenosis induced low back pain with a radicular component. Historically, the terminology used to describe the transforaminal technique of instilling medications into the epidural space and/or exiting structures has varied. These procedures have also been referred to as either diagnostic or therapeutic selective nerve root blocks (SNRBs). Although this procedure is typically used to "selectively" treat isolated pathology, the "SNRB" terminology suggests that one can selectively diagnose or treat a specific nerve root as a pain generator by anesthetizing or blocking it. It has been recently demonstrated that L4 and L5 SNRBs are often non-"selective" by investigating the extent of epidural contrast flow patterns after injecting 1.0 mL of contrast. Our study attempts to identify the minimum injectate volume at which LS-TFESIs may still be considered "selective" with no injectate extending to either the adjacent (superior and/or inferior) levels or to the contralateral side. OBJECTIVE: Quantitatively evaluate contrast flow level selectivity noted during fluoroscopically guided lumbosacral transforaminal epidural steroid injections (LS-TFESIs). STUDY DESIGN: Prospective, nonrandomized, observational human study. METHODS: Thirty patients (female = 10, male = 20) undergoing LS-TFESIs were investigated. After confirming appropriate spinal needle position with biplanar imaging, 4.0 mL of nonionic contrast was slowly injected. Fluoroscopic images were recorded at 0.5 mL increments. These biplanar contrast flow images were evaluated to determine which 0.5 mL volume increment was no longer specific for the injected level. In particular, we documented when contrast extended either to a superior or inferior spinal segment or crossed the midline spine to the contralateral side. RESULTS: After injecting 0.5 mL of contrast, 30% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. After injecting 1.0 mL of contrast, 67% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. After injecting 1.5 mL of contrast, 87% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. After injecting 2.5 mL of contrast, 90% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. CONCLUSIONS: Diagnostic LS-TFESI or SNRB blocks limiting injectate to a single, ipsilateral segmental level cannot reliably be considered diagnostically selective with volumes exceeding 0.5mL. Injectate volumes greater than 0.5mL are consistently non-selective and cannot be used reliably for diagnostic block procedures in the epidural space.

Allergic reactions to gadodiamide following interventional spinal procedures: a report of 4 cases.

Gadodiamide is currently considered a safe alternative for use in interventional spinal procedures in persons with a documented allergic response to iodine-based contrast dyes and with adequate renal function. The most common reactions to gadodiamide are nausea, emesis, and headache. These reactions usually are self-limited and are reported to occur in less than 1% of patients. We report the cases of 4 patients who developed an allergic reaction to gadodiamide, 3 of whom presented within the same week, after minimally invasive interventional spinal procedures at an outpatient private practice facility. Furthermore, 3 of the 4 patients had previously been exposed to gadodiamide during prior interventional spinal procedures without reaction, and the fourth patient had a reaction on the first exposure. The clinical presentation was manifested as a rash in 3 of the 4 patients, whereas the fourth patient experienced fevers and rigors along with rash. Because the injections of gadodiamide were not administered in succession, different vials of gadodiamide were used in each patient, and the injections were given by different clinicians at different spinal levels, we hypothesize that these patients experienced an allergic reaction, rather than contamination of the gadodiamide solution. These cases may call into question the safety of gadodiamide as an alternative contrast agent.

Role of radiofrequency denervation in lumbar zygapophyseal joint synovitis in baseball pitchers: a clinical experience.

Lumbar zygapophyseal joints have long been considered a source of low back pain with or without leg pain. The objective of this prospective study was to investigate the therapeutic effectiveness of lumbar zygapophyseal joint radiofrequency denervation (RFD) followed by physical therapy, for the treatment of refractory lumbar zygapophyseal joint mediated low back pain secondary to lumbar zygapophyseal joint synovitis, in baseball pitchers. Participants included twelve male baseball pitchers with a diagnosis of lumbar zygapophyseal joint synovitis mediated low back pain and a subsequent difficulty in pitching. These athletes underwent a trial of treatment, including oral anti-inflammatory medication, physical therapy, osteopathic manipulations, and fluoroscopically guided intra-articular zygapophyseal joint injection utilizing steroid and local anesthetic agent. Failure to progress led to these athletes receiving percutaneous, fluoroscopically-guided, radiofrequency denervation of the bilateral L 4-L5 and L5-S1 zygapophyseal joints. A good response to a diagnostic medial branch block was a prerequisite for RFD treatment. In all cases, the medial branch above and below the involved level was treated. Post procedure, all athletes participated in a phased physical therapy program followed by a progressive return to pitching. Success was defined as the ability to return to pre-procedure level of baseball pitching combined with greater than 50% low back pain reduction. Pre- and post-RFD, Visual Analog (Numeric) Scale (VAS) and Roland-Morris (R-M) tests were administered. Ten out of 12 (83%) athletes were able to return to pitching at a level attained prior to RFD. All 12 patients, experienced statistically significant low back pain relief, with a mean pre-RFD VAS of 8.4; mean post-RFD VAS of 1.7; mean pre-RFD R-M score of 12.3; and mean post-RFD R-M score of 22.3. In conclusion, athletes, experiencing lumbar zygapophyseal joint mediated low back pain secondary to zygapophyseal joint synovitis and have failed more conservative management may benefit from radiofrequency zygapophyseal joint denervation followed by a formal rehabilitation program.