Cost-effectiveness of Lumbar Epidural Steroid Injections

Rationale for fluoroscopic guidance in spine injections

Spine injections are commonly performed in the treatment of back pain. The purpose of this article is to review the current literature surrounding image guided spine injections focusing on scenarios where fluoroscopic guidance can be advantageous in addition to discussing similarities among the different modalities.

Do Epidural Steroid Injections Affect Outcomes and Costs in Cervical Degenerative Disease? A Retrospective MarketScan Database Analysis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To investigate the effect of preoperative epidural steroid injection (ESI) on quality outcomes and costs in patients undergoing surgery for cervical degenerative disease.

METHODS

We queried the MarketScan database, a national administrative claims dataset, to identify patients who underwent cervical degenerative surgery from 2007 to 2016. Patients under 18 and patients with history of tumor or trauma were excluded. Patients were stratified by ESI use at 3, 6, 12, 18, and 24 or more months preoperative. Propensity score matched controls for these groups were obtained. Baseline demographics, postoperative complications, reoperations, readmissions, and costs were compared via univariate and multivariate analysis.

RESULTS

97 117 patients underwent cervical degenerative surgery, of which 29 963 (30.7%) had ESI use at any time preoperatively. Overall, 90-day complication rate was not significantly different between groups. The ESI cohorts had shorter length of stay, but higher 90-day readmission and reoperation rates. ESI use was associated with higher total payments through the 2-year follow-up period. Among patients who received preoperative ESI, male sex, history of cancer, obesity, PVD, rheumatoid arthritis, nonsmokers, cervical myelopathy, BMP use, anterior approach, 90-day complication, 90-day reoperation, and 90-day readmission were independently associated with increased 90-day total cost.

CONCLUSION

ESI can offer pain relief in some patients refractory to other conservative management techniques, but those who eventually undergo surgery have greater healthcare resource utilization. Certain characteristics can predispose patients who receive preoperative ESI to incur higher healthcare costs.

Multicenter study evaluating factors associated with treatment outcome for low back pain injections

BACKGROUND

There has been a worldwide surge in interventional procedures for low back pain (LBP), with studies yielding mixed results. These data support the need for identifying outcome predictors based on unique characteristics in a pragmatic setting.

METHODS

We prospectively evaluated the association between over two dozen demographic, clinical and technical factors on treatment outcomes for three procedures: epidural steroid injections (ESIs) for sciatica, and sacroiliac joint (SIJ) injections and facet interventions for axial LBP. The primary outcome was change in patient-reported average pain intensity on a numerical rating scale (average NRS-PI) using linear regression. For SIJ injections and facet radiofrequency ablation, this was average LBP score at 1 and 3 months postprocedure, respectively. For ESI, it was average leg pain 1- month postinjection. Secondary outcomes included a binary indicator of treatment response (success).

RESULTS

346 patients were enrolled at seven hospitals. All groups experienced a decrease in average NRS-PI (p<0.0001; mean 1.8±2.6). There were no differences in change in average NRS-PI among procedural groups (p=0.50). Lower baseline pain score (adjusted coefficient -0.32, 95% CI -0.48 to -0.16, p<0.0001), depressive symptomatology (adjusted coefficient 0.076, 95% CI 0.039 to 0.113, p<0.0001) and obesity (adjusted coefficient 0.62, 95% CI 0.038 to 1.21, p=0.037) were associated with smaller pain reductions. For procedural outcome, depression (adjusted OR 0.94, 95% CI 0.91, 0.97, p<0.0001) and poorer baseline function (adjusted OR 0.59, 95% CI 0.36, 0.96, p=0.034) were associated with failure. Smoking, sleep dysfunction and non-organic signs were associated with negative outcomes in univariate but not multivariate analyses.

CONCLUSIONS

Identifying treatment responders is a critical endeavor for the viability of procedures in LBP. Patients with greater disease burden, depression and obesity are more likely to fail interventions. Steps to address these should be considered before or concurrent with procedures as considerations dictate.

TRIAL REGISTRATION NUMBER

NCT02329951.

Effect of epidural polydeoxyribonucleotide in a rat model of lumbar foraminal stenosis

Background

We aimed to investigate the effect of epidural polydeoxyribonucleotide (PDRN) on mechanical allodynia and motor dysfunction in a rat model of lumbar foraminal stenosis (LFS).

Methods

This study was conducted in two stages, using male Sprague-Dawley rats. The rats were randomly divided into eight groups. In the first stage, the groups were as follows vehicle (V), sham (S), and epidural PDRN at 5 (P5), 8 (P8), and 10 (P10) mg/kg; and in the second stage, they were as follows intraperitoneal PDRN 8 mg/kg, epidural 3,7-dimethyl-1-propargilxanthine (DMPX) (0.1 mg/kg), and DMPX (0.1 mg/kg). The LFS model was established, except for the S group. After an epidural injection of the test solutions, von Frey and treadmill tests were conducted for 3 weeks. Subsequently, histopathologic examinations were conducted in the V, S, P5, and P10 groups.

Results

A total of 65 rats were included. The P8 and P10 groups showed significant recovery from mechanical allodynia and motor dysfunction at all time points after drug administration compared to the V group. These effects were abolished by concomitant administration of DMPX. On histopathological examination, no epineurial inflammation or fibrosis was observed in the epidural PDRN groups.

Conclusions

Epidural injection of PDRN significantly improves mechanical allodynia and motor dysfunction in a rat model of LFS, which is mediated by the spinal adenosine A_2A receptor. The present data support the need for further research to determine the role of epidural PDRN in spinal stenosis treatment.

Heterogeneity Among Hospitals in the Percentages of All Lumbosacral Epidural Steroid Injections Where the Patient Had Received 4 or More in the Previous Year

BACKGROUND

Current guidelines for the administration of therapeutic epidural injections suggest that these be limited to a maximum of 4 per year. We sought to gain an understanding of the proportion of lumbosacral epidural injections administered to patients who had received ≥4 such injections during the preceding 364 days, and whether these proportions varied among hospitals.

METHODS

This observational cohort study included data from all facilities owned by the 121 nonfederal hospitals in the State of Iowa, July 2012 through September 2017. One end point was the percentage of all lumbar or sacral transforaminal or interlaminar epidural injections where the patient had received ≥4 such injections during the preceding 364 days. Comparisons also were made among hospitals' percentages of injections that were the fifth or greater (ie, patient had already received ≥4 during preceding 364 days) using Bonferroni-adjusted conservative 95% confidence intervals.

RESULTS

There were 48,270 unique patients who underwent at least 1 lumbosacral epidural steroid injection. The patients received care at 112 hospitals' facilities. Most patients received no additional steroid injections within 364 subsequent calendar days after the first steroid injection (54.1%). There were ≥5 steroid injections for 1.27% of patients (ie, the injection was the fifth or greater). Among the 39 hospitals in Iowa that performed overall at least 1 steroid injection every 4 days, there were 6 hospitals at which the percentages of injections that were the fifth or greater significantly exceeded the overall prevalence of 1.91% (range: 3.0%-6.4%). There were 14 of the 39 hospitals with prevalences significantly less.

CONCLUSIONS

Although most patients received only 1 lumbosacral steroid injection within 1 year, 1.27% of patients received 5 or more, and 1.91% of injections were the fifth or greater. Several hospitals had significantly greater than the overall average percent of steroid injections which were fifth or more. This heterogeneity warrants study of whether annual steroid injections per patient should be a clinical quality measure for the care received by patients with lower back pain or whether payment should be greater when injections are in accordance with guidelines.

Comparing the short-term cost-effectiveness of epidural steroid injections and medical management alone for discogenic lumbar radiculopathy

OBJECTIVE

Epidural steroid injections (ESIs) are a commonly used treatment strategy for low back pain and lumbar radiculopathy. However, their cost-effectiveness and ability to mediate long-term quality of life (QOL) improvements is debated. We sought to analyze the cost-effectiveness of lumbar epidural steroid injections (ESIs) compared to medical management alone for patients with lumbar radiculopathy and low back pain.

PATIENTS AND METHODS

QOL outcomes were prospectively collected at 3- and 6-months following initial consultation. Metrics included the EuroQol-5 Dimensions (EQ-5D) questionnaire, the Pain Disability Questionnaire (PDQ), the Patient Health Questionnaire (PHQ-9) and the Visual Analogue Scale (VAS). Cost estimations were based on Medicare national payment amounts, median income, and missed workdays. A cost-utility analysis was performed based upon cost estimations and a cost-effectiveness threshold of $100,000/Quality-adjusted life year (QALY).

RESULTS

One hundred forty-one patients met our inclusion/exclusion criteria; 89 received ESI and 52 were treated with medical management alone. Both cohorts showed improved EQ-5D scores at 3 months but were similar to one another: ESI (ΔEQ-5D = 0.06; p = 0.03) and medical-alone (ΔEQ-5D = 0.07; p = 0.03). No significant difference was seen between groups for total costs ($2,190 vs. $1,772; p = 0.18) or cost-utility ratios ($38,710/QALY vs. $27,313/QALY; p = 0.73). At both the 3-month and 6-month endpoints, absolute differences in cost-utility was driven by overall costs as opposed to QALY gains. Medical management alone was more cost effective at both points owing to lower expenditures, however these differences were not significant. No benefits were seen in either group on the EQ-5D or any of the patient reported outcomes at the 6-month time point.

CONCLUSION

ESIs were not cost-effective at either the 3-month or 6-month follow-up period. At 3 months, ESIs provide similar improvements in QOL outcomes relative to medical management and at similar costs. At 6 months, neither ESIs nor conservative management provide significant improvements in QOL outcomes.

The Effect of Preoperative Symptom Duration on Postoperative Outcomes After a Tubular Lumbar Microdiscectomy

STUDY DESIGN

This is a retrospective cohort study.

OBJECTIVE

This study aims to characterize the effect of preoperative symptom duration on postoperative outcomes after minimally invasive lumbar microdiscectomy (MIS LD).

SUMMARY OF BACKGROUND DATA

It is unknown whether extended nonoperative treatment before MIS LD has implications for long-term clinical outcomes even after surgery is performed.

MATERIALS AND METHODS

A prospectively maintained surgical registry of patients undergoing MIS LD by a single surgeon between 2013 and 2017 was reviewed. Preoperative symptom duration was dichotomized into 2 groups (≤6 and >6 mo). Only patients with full clinical data at 6 months postoperative follow-up were included in the study. Clinical outcomes were assessed at 6, 12 weeks, and 6 months after surgery. The number of patients obtaining a minimum clinically important difference was assessed. Groups were compared with the χ analysis and the student t tests for categorical and continuous data, respectively.

RESULTS

In total, 94 patients were identified. A total of 45 patients (47.9%) had symptom duration ≤6 months. No differences in baseline characteristics were found (P>0.05). Patients with shorter symptom duration had significantly greater improvement in Oswestry Disability Index scores at 6 weeks (P=0.004), 12 weeks (P=0.022), and 6 months (P=0.005). Patients with shorter duration of symptoms also obtained minimum clinically important difference for Oswestry Disability Index at a greater rate than those with longer duration of symptoms (P=0.015).

CONCLUSIONS

Although patients who underwent MIS LD within 6 months of symptom onset had similar baseline characteristics compared with patients who underwent surgery after 6 months of symptoms, the patients with longer preoperative symptom duration had worse functional outcomes at 6 months after surgery. These results suggest that earlier MIS lumbar microdiscectomy may provide a functional benefit for patients. Further studies should therefore evaluate the efficacy of nonoperative treatment in the setting of lumbar herniated nucleus pulposus, as prolonged conservative management may potentially impair functional recovery after surgery.

Repeat epidural steroid injections for radicular pain due to lumbar or cervical disc herniation

Aims

The aim of this study was to determine the efficacy of repeat epidural steroid injections as a form of treatment for patients with insufficiently controlled or recurrent radicular pain due to a lumbar or cervical disc herniation.

Patients and Methods

A cohort of 102 patients was prospectively followed, after an epidural steroid injection for radicular symptoms due to lumbar disc herniation, in 57 patients, and cervical disc herniation, in 45 patients. Those patients with persistent pain who requested a second injection were prospectively followed for one year. Radicular and local pain were assessed on a visual analogue scale (VAS), functional outcome with the Oswestry Disability Index (ODI) or the Neck Pain and Disability Index (NPAD), as well as health-related quality of life (HRQoL) using the 12-Item Short-Form Health Survey questionnaire (SF-12).

Results

A second injection was performed in 17 patients (29.8%) with lumbar herniation and seven (15.6%) with cervical herniation at a mean of 65.3 days (sd 46.5) and 47 days (sd 37.2), respectively, after the initial injection. All but one patient, who underwent lumbar microdiscectomy, responded satisfactorily with a mean VAS for leg pain of 8.8 mm (sd 10.3) and a mean VAS for arm pain of 6.3 mm (sd 9) one year after the second injection, respectively. Similarly, functional outcome and HRQoL were improved significantly from the baseline scores: mean ODI, 12.3 (sd 12.4; p < 0.001); mean NPAD, 19.3 (sd 24.3; p = 0.041); mean SF-12 physical component summary (PCS) in lumbar herniation, 46.8 (sd 7.7; p < 0.001); mean SF-12 PCS in cervical herniation, 43 (sd 6.8; p = 0.103).

Conclusion

Repeat steroid injections are a justifiable form of treatment in symptomatic patients with lumbar or cervical disc herniation whose symptoms are not satisfactorily relieved after the first injection. Cite this article: Bone Joint J 2018;100-B:1364–71.