Influence of Epidural Steroid Injection on Adrenal Function

Paravertebrally-Injected Multifunctional Hydrogel for Sustained Anti-Inflammation and Pain Relief in Lumbar Disc Herniation

Pain caused by lumbar disc herniation (LDH) severely compromises patients' quality of life. The combination of steroid and local anesthetics is routinely employed in clinics to alleviate LDH-induced pain. However, the approach only mediates transient efficacy and requires repeated and invasive lumbar epidural injections. Here a paravertebrally-injected multifunctional hydrogel that can efficiently co-load and controlled release glucocorticoid betamethasone and anesthetics ropivacaine for sustained anti-inflammation, reactive oxygen species (ROS)-removal and pain relief in LDH is presented. Betamethasone is conjugated to hyaluronic acid (HA) via ROS-responsive crosslinker to form amphiphilic polymer that self-assemble into particles with ropivacaine loaded into the core. Solution of drug-loaded particles and thermo-sensitive polymer rapidly forms therapeutic hydrogel in situ upon injection next to the herniated disc, thus avoiding invasive epidural injection. In a rat model of LDH, multifunctional hydrogel maintains the local drug concentration 72 times longer than free drugs and more effectively inhibits the expression of pro-inflammatory cytokines and pain-related molecules including cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2). Therapeutic hydrogel suppresses the LDH-induced pain in rats for 12 days while the equivalent dose of free drugs is only effective for 3 days. This platform is also applicable to ameliorate pain caused by other spine-related diseases.

Serum cortisol level to screen for significant hypothalamic-pituitary-adrenal axis suppression in patients receiving multiple steroid injections

BACKGROUND

Morning serum cortisol level (mSCL) is a practical screening tool for hypothalamic-pituitary-adrenal (HPA) axis suppression and has been used to assess for duration of cortisol deficiency after epidural and peripheral glucocorticoid injections. More evidence is needed to establish the utility of mSCL in patients undergoing repeat injections with increasing cumulative glucocorticoid equivalent dose (CGED) that could place them at higher risk of HPA axis suppression.

OBJECTIVES

To estimate the prevalence of spine injection candidates with significant HPA axis suppression (sigAS), to understand the correlation between 12 months of CGED and the presence of sigAS based on the timing of mSCL collection after the most recent glucocorticoid injection (within 6 weeks or between 6 weeks and 12 months), and to investigate demographic and clinical factors relating to sigAS.

METHODS

Retrospective chart review of patients scheduled for spine injection who had an associated mSCL and documented histories of prior glucocorticoid injections. The steroid name, dose, type, and procedure location were recorded for each injection that occurred within 12 months before mSCL. CGED was calculated from standard glucocorticoid equivalent conversion factors.

RESULTS

SigAS was present in 7.8% to 22% of the analysis cohorts. There was no association found between CGED and sigAS regardless of timing of mSCL. There was a trend toward lower mSCL and sigAS with increasing CGED. There were no significant relationships found between sigAS and overall demographic or clinical factors.

CONCLUSIONS

A 3-fold reduction in the rate of sigAS was noted 6 weeks after the most recent steroid injection. Using mSCL provides a template to investigate the impact of CGED and the best timing for mSCL collection in order to define a more practical guideline to identify patients at higher risk of sigAS earlier and plan for future spine injections.

Pain Relief After Selective Nerve Root Block as a Predictor of Postoperative Functional Outcome in Patients with Degenerative Lumbar Spinal Stenosis Patients Undergoing Decompressive Surgery

STUDY DESIGN

Retrospective study of data collected prospectively.

OBJECTIVE

To investigate changes in the degree of lower leg radiating pain (LLRP) after selective nerve root block (SNRB) and to evaluate associations of this change with postoperative improvements in symptom severity, functional outcomes, and quality of life.

SUMMARY OF BACKGROUND DATA

SNRB is routinely performed as an initial treatment for lumbar foraminal or lateral recess stenosis with LLRP. The degree of improvement after SNRB has been suggested to predict the improvement in postoperative pain and functional outcomes. However, there have been no studies on the predictive value of this parameter.

METHODS

We enrolled 60 patients who underwent SNRB followed by decompressive surgery. They were divided into three groups. The degree of improvement was evaluated as a percentage of the pre-injection values. Functional outcomes of the spine were assessed using the Oswestry Disability Index (ODI) and Roland-Morris Disability Questionnaire (RMDQ). Quality of life was assessed using the 36-item Short Form Survey (SF-36) physical component score (PCS) and mental component score (MCS). The degree of LLRP was measured preoperatively and at 6, 12, and 24 months after surgery. These functional outcomes were evaluated preoperatively and at 12 and 24 months after surgery.

RESULTS

The improvement in LLRP in the short term (6 hours after SNRB) was found to be statistically significantly associated with the improvement in LLRP at 12 months after SNRB (P = 0.044, correlation coefficient = 0.261). No relationship between pain improvement after SNRB and functional outcome was identified.

CONCLUSION

The degree of improvement in symptoms 6 hours after SNRB can predict the degree of improvement in LLRP at 12 months after surgery. However, symptomatic improvement after SNRB does not predict postoperative functional outcome or quality of life.Level of Evidence: 4.

Comparison of the effects of corticosteroid and hyaluronic acid-carboxymethylcellulose solution on selective nerve root block for lumbar radiculopathy: A prospective, double-blind, randomized controlled clinical trial

BACKGROUND

Selective nerve root block (SNRB) was shown to effectively control radiating pain and reduce the need for surgical intervention. However, repetitive injections may trigger corticosteroid-induced side effects (hypercorticism, hyperglycemia, or fluid retention). This study aims to compare the potency of hyaluronic acid-carboxymethylcellulose (HA-CMC) solution versus that of corticosteroids regarding lower leg radiating pain (LLRP) improvement and functional outcome.

METHODS

Among 128 patients, 44 patients who complain about having LLRP due to lumbar spinal stenosis and do not have neurological symptoms requiring surgery were enrolled for this study. Group A with 22 patients injected with cocktail A (local anesthetics and corticosteroid) and group B with 22 patients injected with cocktail B (local anesthetics and HA-CMC). Outcome measures were the visual analog scale (VAS), Oswestry Disability Index (ODI), and short form-36 (SF-36). All patients were asked to fill in the questionnaires during the follow-up assessment period at 3 days, 7 days, 2 weeks, 6 weeks, and 12 weeks.

RESULTS

In all time periods, there were no statistical differences between the two groups for VAS scores and VAS improvement over time, ODI scores and ODI improvement over time, and SF-36 PCS scores and SF-36 mental component score scores. Additionally, the 95% confidence interval of the difference in VAS score improvement between the 2 groups in all time periods was within VAS 5.0, which is the minimum clinically relevant difference.

CONCLUSIONS

Considering the adverse effects of corticosteroids, and the similar LLRP improvements, functional outcome, and quality of life, the HA-CMC solution may be an alternative option to corticosteroid in SNRB.

[Lumbar transforaminal epidural block for treatment of low back pain with radicular pain]

OBJECTIVE

To evaluate the efficacy of lumbar transforaminal epidural block (LTEB) for treatment of low back pain with radicular pain.

METHODS

We retrospectively analyzed the clinical data of 78 patients with low back pain and radicular pain admitted to the Department of Orthopedics of Beijing Chuiyangliu Hospital from March, 2017 to April, 2019. Thirty-three of the patients received treatment with LTEB (LTEB group), and 45 received comprehensive conservative treatment including traction, massage, acupuncture and physiotherapy (control group). The demographic and clinical data of the two groups were compared. The patients were followed up for 3 to 24 months, and numerical rating scale (NRS) and Oswestry disability index (ODI) scores of the patients were evaluated before the treatment and at 2 weeks, 1 month and 3 months after discharge to assess the efficacy of the treatment.

RESULTS

The mean operation time of LTEB was 25.7 7.5 min (15-45 min). After the operation, 5 patients developed weakness of the lower limbs but all recovered within 24-72 h. The patients receiving LTEB all showed significantly decreased NRS scores for low back and radicular pain and ODI scores after the operation (P=0.001). At 2 weeks after the operation, the patients receiving LTEB showed significant relief of low back pain as compared with the patients in the control group (t=2.224, P=0.034), and the difference in NRS scores for low back pain between the two groups tended to diminish over time (F=1.743, P=0.183). Treatment with LTEB resulted in obvious relief of radicular pain and significant reduction of the ODI score of the patients (P < 0.001), and such improvements became more obvious over time after LTEB (P < 0.01).

CONCLUSIONS

As a minimally invasive approach, LTEB is effective for treatment of low back pain with radicular pain and can produce good short-term effects of pain relief and functional improvement.

Symptomatic COVID-19 infections in outpatient image-guided corticosteroid injection patients during the lockdown phase

BACKGROUND

Musculoskeletal pain is a debilitating problem treated with image-guided corticosteroid injections. During the COVID-19 pandemic, multiple societies issued caution statements because of the unknown effect of corticosteroids on the patient's immune system. The purpose is to determine if image-guided corticosteroid injections administered during the COVID-19 lockdown phase were associated with a higher infection rate compared to the general population.

MATERIALS AND METHODS

In a prospective study, patients undergoing image-guided corticosteroid injections for pain management during the lockdown phase between April 15 and May 22, 2020, were enrolled. One month after the injection, patients were surveyed by telephone for any COVID-19-related symptoms, and the electronic medical record (EMR) was reviewed for symptoms and test results.

RESULTS

Seventy-one subjects were recruited, 31 (44%) females, 40 (56%) males, ages 58 ± 17 (20-92) years. Follow-up was available in 66 (93%) of subjects, 60 (91%) by phone survey and EMR, 6 (9%) by EMR only, 45 ± 22 (19-83) days after injection. One (1/66, 1.52%; 95% CI 0.04-8.2%) 25-year-old male subject developed symptomatic infection 19 days after a tibiotalar injection. The prevalence of COVID-19 cases in the state of Massachusetts was 0.91% (62,726/6,892,503) during the study period. There was no significant difference in the rate of occurrence of new cases of COVID-19 infection between the corticosteroid injection group and the general population (p = 0.44).

CONCLUSION

Image-guided corticosteroid injections for pain management performed during the lockdown phase of the COVID-19 pandemic were not associated with a higher infection rate compared to the general population.

To compare the analgesic efficacy of two different doses of epidural ketamine in chronic low back-pain patients: A randomised double-blind study

Background and Aims:

Ketamine, an adjunct to epidural steroid injections (ESI) for chronic back-pain provides better quality and prolonged duration of analgesia. The present study aims to evaluate the analgesic efficacy in terms of pain scores, duration of pain-free period, patient satisfaction score (PSS) and number of repeat injections with 25 mg versus 50 mg ketamine as adjuvants to ESI.

Methods:

In a prospective, randomised, double-blind trial at a tertiary care hospital, 60 patients of chronic low back-pain of either sex, aged 18–65 years, received preservative free 25 mg ketamine in Group I and 50 mg ketamine in Group II as adjunct to 40 mg triamcinolone in total 6 ml volume given epidurally. Baseline data along with follow-ups at 2, 4, 8 and 12 weeks post-procedure included assessment of pain using Visual Analogue Scale (VAS), duration, number of repeat blocks using PSS, Quality of Life (QoL) and side-effects. Categorical data analysed using the Chi-Square test, and continuous data using paired t-test.

Results:

Pain evaluation within the groups over time showed significant improvement from baseline (P = 0.000), and between the groups showed comparable VAS scores at 12 weeks (P = 0.392). The PSS, pain-free duration and number of repeat injections were also statistically comparable. However, the QoL improved more in Group II vs Group I (P = 0.024). The short-lasting side effects were more in Group II, but no features of neurotoxicity were observed in any patient.

Conclusion:

The analgesic efficacy of adjuvant therapy with 50 mg ketamine appeared comparable to 25 mg ketamine. Although, there was a better quality of life and longer pain-free interval with 50 mg ketamine, the side effects were more.