Background

Baclofen commonly is used to manage spasticity caused by central nervous system lesions or dysfunction. Although both intrathecal and oral delivery routes are possible, no study has directly compared clinical outcomes associated with these 2 routes of treatment.

Objective

To compare spasticity levels, pain, sleep, fatigue, and quality of life between individuals receiving treatment with intrathecal versus oral baclofen.

Design

Cross-sectional matched cohort survey study.

Setting

Urban academic rehabilitation outpatient clinics.

Participants

Adult patients with spasticity, treated with intrathecal or oral baclofen for at least 1 year, matched 1:1 for age, gender, and diagnosis.

Methods

Standardized surveys were administered during clinic appointments or by telephone.

Main outcome measures

Surveys included the Penn Spasm Frequency Scale, Brief Pain Inventory, Epworth Sleepiness Scale, Fatigue Severity Scale, Life Satisfaction Questionnaire, and Diener Satisfaction with Life Scale.

Results

A total of 62 matched subjects were enrolled. The mean (standard deviation [SD]) age was 46 (11) years with a mean duration of intrathecal baclofen or oral baclofen treatment of 11 (6) and 13 (11) years, respectively. There were 40 (64%) male and 22 (36%) female subjects. Primary diagnoses included spinal cord injury (n = 38), cerebral palsy (n = 10), stroke (n = 10), and multiple sclerosis (n = 4). The mean (SD) dose of intrathecal and oral baclofen at the time of survey were 577 (1429) μg/day and 86 (50) mg/day, respectively. Patients receiving intrathecal compared with oral baclofen experienced significantly fewer (1.44 [0.92] versus 2.37 [1.12]) and less severe (1.44 [0.92] versus 2.16 [0.83]) spasms, respectively as measured by the Penn Spasm Frequency Scale (P < .01; P < .01). There were no significant differences in pain, sleep, fatigue, and quality of life between groups. Subanalysis of patients with SCI mirrored results of the entire study sample, with significant decreases in spasm frequency and severity associated with intrathecal compared to oral baclofen (P < .01; P < .01), but no other between group differences. The mean (SD) percent change in dose of oral (21% [33%]) compared with intrathecal (3% [28%]) baclofen was significantly larger two years prior to the date of survey (P = .02).

Conclusions

Long-term treatment with intrathecal compared with oral baclofen is associated with reduced spasm frequency and severity as well as greater dose stability. These benefits must be weighed against the risks of internal pump and catheter placement in patients considering intrathecal baclofen therapy.

Objective

Investigate associations between endplate and motion segment magnetic resonance imaging (MRI) characteristics and treatment outcomes following basivertebral nerve radiofrequency ablation (BVN RFA) in patients with clinically suspected vertebral endplate pain (VEP).

Design

Aggregated cohort study of 296 participants treated with BVN RFA from three prospective clinical trials.

Methods

Baseline MRI characteristics were analyzed using stepwise logistic regression to identify factors associated with treatment success. Predictive models used three definitions of treatment success: (1) ≥50% low back pain (LBP) visual analog scale (VAS), (2) ≥15-point Oswestry Disability Index (ODI), and (3) ≥50% VAS or ≥15-point ODI improvements at 3-months post-BVN RFA.

Results

The presence of lumbar facet joint fluid (odds ratio [OR] 0.586) reduced the odds of BVN RFA treatment success in individuals with clinically suspected VEP. In patients with a less advanced degenerative disc disease (DDD) profile, a > 50% area of the endplate with bone marrow intensity changes (BMIC) was predictive of treatment success (OR 4.689). Both regressions areas under the curve (AUCs) were under 70%, indicating low predictive value. All other vertebral endplate, intervertebral disc, nerve roots facet joint, spinal segmental alignment, neuroforamina, lateral recesses, and central canal MRI characteristics were not associated with BVN RFA success.

Conclusions

In patients with vertebrogenic low back pain with Modic changes, the presence of degenerative findings of the anterior and posterior column was not associated with a clinically important impact on BVN RFA treatment success. None of the models demonstrated strong predictive value, indicating that the use of objective imaging biomarkers (Type 1 and/or 2 Modic changes) and a correlating presentation of pain remain the most useful patient selection factors for BVN RFA.

Myth

Corticosteroid injection for the treatment of pain is known to decrease the efficacy of the adenovirus vector-based vaccines for COVID-19.

Fact

There is currently no direct evidence to suggest that a corticosteroid injection before or after the administration of an adenovirus vector-based COVID-19 vaccine decreases the efficacy of the vaccine. However, based on the known timeline of hypothalamic-pituitary-adrenal axis suppression following epidural and intraarticular corticosteroid injections, and the timeline of the reported peak efficacy of the Janssen and AstraZeneca vaccines, physicians should consider timing an elective corticosteroid injection such that it is administered no less than 2 weeks prior to and no less than 2 weeks following a COVID-19 adenovirus vector-based vaccine dose, whenever possible. We emphasize the importance of risk/benefit analysis and shared decision making in determining the timing of corticosteroid injections for pain indications in relation to receipt of a COVID-19 vaccine given that patient-specific factors will vary.

Purpose

Vertebral endplate bone marrow lesions ("Modic changes", MC) are associated with chronic low back pain (CLBP). Bone marrow composition in MC is poorly understood. The goals of this study were to: (1) measure bone marrow fat fraction (BMF) in CLBP patients with MC using water-fat MRI and (2) assess the relationship between BMF measurements and patient-reported clinical characteristics.

Methods

In this cross-sectional study, 42 CLBP patients (men, n = 21; age, 48 ± 12.4 years) and 18 asymptomatic controls (men, n = 10; 42.7 ± 12.8 years) underwent 3 T MRI between January 2016 and July 2018. Imaging consisted of T₁- and T₂-weighted sequences to evaluate MC and spoiled gradient-recalled echo sequence with asymmetric echoes and least-squares fitting to measure BMF. BMF was compared between vertebrae with and without MC using mixed effects models. The relationship between the BMF measurements and patient-reported disability scores was examined using regression.

Results

Twenty-seven subjects (26 CLBP, 1 control) had MC, and MC presence coincided with significantly altered BMF. In MC 1, BMF was lower than endplates without MC (absolute difference -22.3%; p < 0.001); in MC 2, BMF was higher (absolute difference 21.0%; p < 0.001). Absolute BMF differences between affected and unaffected marrow were larger in patients with greater disability (p = 0.029-0.032) and were not associated with pain (p = 0.49-0.83).

Conclusion

BMF is significantly altered in MC. Water-fat MRI enables BMF measurements that may eventually form the basis for quantitative assessments of MC severity and progression.

Objective

Develop pain location "maps" and investigate the relationship between low back pain (LBP)-exacerbating activities and treatment response to basivertebral nerve radiofrequency ablation (BVN RFA) in patients with clinically suspected vertebral endplate pain (VEP).

Design

Aggregated cohort study of 296 patients treated with BVN RFA at 33 centers in three prospective trials.

Methods

Participant demographics, pain diagrams, and LBP-exacerbating activities were analyzed for predictors using stepwise logistic regression. Treatment success definitions were: (1) ≥50% LBP visual analog scale (VAS), (2) ≥15-point Oswestry Disability Index (ODI), and (3) ≥50% VAS or ≥15-point ODI improvements at 3 months post-BVN RFA.

Results

Midline LBP correlated with BVN RFA treatment success in individuals with clinically-suspected VEP. Duration of pain ≥5 years (OR 2.366), lack of epidural steroid injection within 6 months before BVN RFA (OR 1.800), lack of baseline opioid use (OR 1.965), LBP exacerbation with activity (OR 2.099), and a lack of LBP with spinal extension (OR 1.845) were factors associated with increased odds of treatment success. Regressions areas under the curve (AUCs) were under 70%, indicative of low predictive value.

Conclusions

This study demonstrates that midline LBP correlates with BVN RFA treatment success in individuals with VEP. While none of the regression models demonstrated strong predictive value, the pain location and exacerbating factors identified in this analysis may aid clinicians in identifying patients where VEP should be more strongly suspected. The use of objective imaging biomarkers (Type 1 and/or 2 Modic changes) and a correlating presentation of anterior spinal element pain remain the most useful patient selection factors for BVN RFA.

Myth

Corticosteroid injection for the treatment of pain and inflammation is known to decrease the efficacy of the messenger ribonucleic acid (mRNA) vaccines for coronavirus disease 2019 (COVID-19).

Fact

There is currently no direct evidence to suggest that a corticosteroid injection before or after the administration of an mRNA COVID-19 vaccine decreases the efficacy of the vaccine.However, based on the known timeline of hypothalamic-pituitary-adrenal (HPA) axis suppression following epidural and intraarticular corticosteroid injections, and the timeline of the reported peak efficacy of the Pfizer-BioNTech and Moderna vaccines, physicians should consider timing an elective corticosteroid injection such that it is administered no less than 2 weeks prior to a COVID-19 mRNA vaccine dose and no less than 1 week following a COVID-19 mRNA vaccine dose, whenever possible.

Vertebral endplate bone marrow lesions, visualized on magnetic resonance imaging (MRI) as Modic changes (MC), are associated with chronic low back pain (cLBP). Since guidelines recommend against routine spinal MRI for cLBP in primary care, MC may be underdiagnosed. Serum biomarkers for MC would allow early diagnosis, inform clinical care decisions, and supplement treatment monitoring. We aimed to discover biomarkers in the blood serum that correlate with MC pathophysiological processes. For this single-site cross-sectional study, we recruited 54 subjects with 38 cLBP patients and 16 volunteers without a history of LBP. All subjects completed an Oswestry Disability Index (ODI) questionnaire and 10-cm Visual Analog Score (VAS) for LBP (VASback) and leg pain. Lumbar T1-weighted and fat-saturated T2-weighted MRI were acquired at 3T and used for MC classification in each endplate. Blood serum was collected on the day of MRI. Biomarkers related to disc resorption and bone marrow fibrosis were analyzed with enzyme-linked immune-absorbent assays. The concentration of biomarkers between no MC and any type of MC (AnyMC), MC1, and MC2 were compared. The Area Under the Curve (AUC) of the Receiver Operating Characteristics were calculated for each biomarker and for bivariable biomarker models. We found that biomarkers related to type III and type IV collagen degradation and formation tended to correlate with the presence of MC (p = 0.060-0.088). The bivariable model with the highest AUC was PRO-C3 + C4M and had a moderate diagnostic value for AnyMC in cLBP patients (AUC = 0.73, specificity = 78.9%, sensitivity = 73.7%). In conclusion, serum biomarkers related to the formation and degradation of type III and type IV collagen, which are key molecules in bone marrow fibrosis, correlated with MC presence. Bone marrow fibrosis may be an important pathophysiological process in MC that should be targeted in larger biomarker and treatment studies.