Absence of Iodinated Contrast Hypersensitivity and Characterization of Gadolinium Utilization in an Interventional Pain Population.

BACKGROUND: Iodinated contrast media (ICM) allergy labels pose a unique clinical problem for the interventional pain physician due to the drawbacks of gadolinium for enhancement during pain procedures, as well as the reluctance to add to the cumulative steroid burden with steroid premedication. However, the risks of ICM hypersensitivity specific to this setting have not been previously described. METHODS: We aimed to describe the incidence of ICM-induced hypersensitivity during the performance of epidural injections in a large healthcare system. We also sought to characterize preexisting ICM allergy labels and how these affected consequent gadolinium utilizations in this population. RESULTS: 6,471 epidural pain procedures requiring contrast enhancement were performed during the 18-month study period. There were no reported contrast-induced hypersensitivity reactions in this time. 108 patients (1.6%) had a preexisting ICM allergy; a shellfish/seafood allergy was recorded in 118 patients (1.82%), and 51 charts (0.78%) were labeled with "iodine" allergy. 183 individuals received gadolinium for enhancement during epidural steroid injections. 96.7% of gadolinium utilization occurred in the context of preexisting allergy labels in the electronic medical record. Of note, 20 patients (18.5%) with ICM allergy labels also received iodinated contrast, and this was uneventful in all cases. CONCLUSION: Our results suggest that ICM-associated hypersensitivity is very rare during epidural procedures and the incidence is significantly lower than expected based on reaction rates during intravascular administration. This may be related to both dose as well as route of administration. The establishment of a protocol for safe workup of ICM allergy labels would be useful in optimizing pain procedures.

Allogeneic mesenchymal precursor cells treatment for chronic low back pain associated with degenerative disc disease: a prospective randomized, placebo-controlled 36-month study of safety and efficacy.

BACKGROUND CONTEXT PURPOSE: Evaluate the safety and efficacy of a single intradiscal injection of STRO-3+ adult allogeneic mesenchymal precursor cells (MPCs) combined with hyaluronic acid (HA) in subjects with chronic low back pain (CLBP) associated with degenerative disc disease (DDD) through 36-month follow-up. STUDY DESIGN/SETTING: A multicenter, randomized, controlled study conducted at 13 clinical sites (12 in the United States and 1 in Australia). SUBJECT SAMPLE: A total of 100 subjects with chronic low back pain associated with moderate DDD (modified Pfirrmann score of 3-6) at one level from L1 to S1 for at least 6 months and failing 3 months of conservative treatment, including physical therapy were randomized in a 3:3:2:2 ratio to receive 6 million MPCs with HA, 18 million MPCs with HA, HA vehicle control, or saline control (placebo) treatment. OUTCOME MEASURES: Subjects were clinically and radiographically evaluated at 1, 3, 6, 12, 24, and 36 months postinjection. Subject-reported outcomes including adverse events, LBP on a Visual Analog Scale (VAS), Oswestry Disability Index (ODI), SF-36 and Work Productivity and Activity Index were collected. METHODS: Clinical and radiographic measures were collected at each visit. All randomized subjects were included in the safety assessments and analyzed based on the treatment received. Safety assessments included assessments of AEs, physical and radiographic examinations and laboratory testing. Efficacy assessments evaluated changes in VAS, ODI, and modified Pfirrmann (MP) scores between all active and control groups, respectively. Assessments included least squares mean (Mean), LS mean change from baseline (Mean Change) and responder analyses in order to assess the clinical significance of observed changes from baseline. The population for efficacy assessments was adjusted for the confounding effects of post-treatment interventions (PTIs). This study was conducted under an FDA Investigational New Drug application sponsored and funded by Mesoblast. RESULTS: There were significant differences between the control and MPC groups for improvement in VAS and ODI. The PTI-corrected VAS and ODI Means and Mean Change analyses; the proportion of subjects with VAS ≥30% and ≥50% improvement from baseline; absolute VAS score ≤20; and ODI reduction ≥10 and ≥15 points from baseline showed MPC therapy superior to controls at various time points through 36 months. Additionally, the proportion of subjects achieving the minimally important change and clinically significant change composite endpoints for the MPC groups was also superior compared with controls at various time points from baseline to 36 months. There were no significant differences in change in MP score from baseline across the groups. There were also no statistically significant differences in change in modified MP score at the level above or below the level treated between study arms. Both the procedure and treatment were well tolerated and there were no clinical symptoms of immune reaction to allogeneic MPCs. There was a low rate of Treatment Emergent Adverse Events (TEAEs) and Serious Adverse Events, and the rates of these events in the MPC groups were not significantly different from the control groups. One TEAE of severe back pain was possibly related to study agent and one TEAE of implantation site infection was considered to be related to the study procedure. CONCLUSIONS: Results provide evidence that intradiscal injection of MPCs could be a safe, effective, durable, and minimally invasive therapy for subjects who have CLBP associated with moderate DDD.

Atherosclerotic Disease and its Relationship to Lumbar Degenerative Disk Disease, Facet Arthritis, and Stenosis With Computed Tomography Angiography.

BACKGROUND: The intervertebral disk is the largest avascular structure in the body. It relies on passive diffusion from arteries at the periphery of the disk for nutrition. Previous studies have suggested a correlation between vascular disease and lumbar degenerative disk disease (DDD), but the association with facet arthritis and stenosis has not been evaluated. OBJECTIVE: To evaluate the degree of lumbar artery stenosis, aortic atherosclerosis on computed tomography angiography, and its relationship to lumbar DDD, facet arthritis, and spinal canal stenosis. DESIGN: Retrospective case review. SETTING: Academic tertiary care hospital. PARTICIPANTS: Not applicable. METHODS: A total of 300 lumbar arteries (150 lumbar artery pairs of the first to fifth lumbar arteries) were evaluated on consecutive computed tomography angiography scans. Severity of vascular disease of lumbar arteries was documented as normal, mild, moderate, severe, or occluded. Aortic vascular disease was documented along the posterior wall where the lumbar arteries originate. MAIN OUTCOME MEASUREMENTS: The relationship between vascular disease with DDD, facet arthritis, and spinal canal stenosis was examined and further evaluated controlling for age. RESULTS: Lumbar artery and aortic atherosclerosis had a positive relationship with DDD, facet arthritis, and spinal stenosis that was statistically significant (P < .05) even after controlling for age. The correlation coefficient was greatest in the younger age group when looking at lumbar artery vascular disease with DDD (0.73, confidence interval 0.50-0.96, P < .0001) and aortic vascular disease with DDD (0.72, confidence interval 0.49-0.94, P < .0001). The correlation of vascular disease with facet arthritis and stenosis was not strong in the older age group. CONCLUSION: Atherosclerotic disease of the lumbar arteries and aorta correlated with lumbar DDD, facet arthritis, and spinal canal stenosis after we adjusted for age, although the correlation with facet arthritis and spinal canal stenosis was not as strong in the older age group. LEVEL OF EVIDENCE: IV.

Cephalad Lead Migration During a Spinal Cord Stimulation Trial: A Case Presentation.

Spinal cord stimulation is used in the treatment of a variety of pain conditions. Lead migration is among the most common complications associated with spinal cord stimulation. Although there have been reports of caudal lead migration, there have been no reports of significant cephalad lead migration during a spinal cord stimulation trial. Here we report what is potentially the first case of significant cephalad lead migration (from the initial T8 position to C2) during a spinal cord stimulation trial. This case demonstrates that significant lead migration is possible, and this case highlights the importance of adequately securing leads during a trial. LEVEL OF EVIDENCE: V.

Epidural Lipomatosis and Associated Spinal Stenosis-The Impact of Weight Loss: A Case Report.

Lumbar stenosis is a common radiographic finding that sometimes can be symptomatic. It usually results from a degenerative process of hypertrophic facets, ligamentum flavum hypertrophy, and disc involvement. A prominence of fat in the epidural space, epidural lipomatosis, can also be a contributing factor. This case report presents a 55-year-old man with radiographic improvement of epidural lipomatosis and stenosis from dietary weight loss. Given the rising obesity epidemic, practitioners should be cognizant of epidural lipomatosis and consider weight loss as a possible treatment option.