Interventional Pain Medicine最新文献

Objective

Lumbar medial branch (MB) radiofrequency ablation is a common intervention to treat facetogenic low back pain. Consensus among spine pain interventionalists is that the cannula tip should be placed adjacent to the periosteum of the lateral neck of the superior articular process (SAP) to ensure maximum contact with the MB. The spatial relationship of the nerve to the periosteum of the lateral neck of the SAP has not been quantified in 3D. The objectives of the current study were to: 1) use 3D modelling technology to quantify the location along the lateral neck of the SAP where the MB is in direct contact with the periosteum; and 2) identify target site(s) to optimize lumbar MB denervation.

Design

Seventy lumbar dorsal rami in 14 formalin-embalmed specimens were dissected, digitized, and modeled in 3D. The 3D positional data of the MB were used to generate a novel nerve proximity map which provided a method to quantify and visualize the 3D course of the MB in relation to the periosteum of the lateral neck of SAP. The percent of the lateral neck of SAP in contact with the MB was quantified and consistent target site(s) identified.

Results

There was variability in the percentage of the lateral neck of SAP in contact with the MB. The mean percentage of the lateral neck of SAP in contact with the MB for the L1-L5 levels ranged between 57.39 ± 10.72 % (for L1) to 81.54 ± 10.48 % (for L5). The nerve proximity map showed consistent course of the MB along the posterior portion of the lateral neck of SAP and at a novel target site distal to the mamillo-accessory notch (i.e. sub-mammillary landmark).

Conclusion

The percent of the lateral neck that was in contact with the MB was quantified and visualized using a novel nerve proximity mapping methodology which may be used to inform cannula tip depth placement. Further, the nerve proximity maps were used to identify an alternative landmark to extend the length of the MB captured. The proposed sub-mammillary landmark may be a viable target site pending future anatomical and clinical investigations.

Background

True lateral imaging (TLI), obtained by superimposing bilateral lumbar spine structures and aligning superior endplate cortical bone, requires deliberate rotational adjustments of the laterally positioned fluoroscope in both the axial and longitudinal planes. True lateral segmental imaging is necessary to depict true and accurate radiofrequency (RF) cannula positioning relative to bony anatomy during lumbar medial branch radiofrequency neurotomy (LMBRFN).

Objective

To determine the interobserver reliability of TLI during LMBRFN.

Methods

This was a retrospective review of a prospectively generated collection of lateral fluoroscopic images to determine the interobserver reliability of TLI during LMBRFN. Lateral fluoroscopic images were prospectively collected from 34 consecutive L4-5 and L5-S1 LMBRFN procedures during routine clinical practice. Employing International Pain and Spine Intervention Society (IPSIS) LMBRFN and TLI techniques, an RF cannula was positioned parallel to the L3 and L4 medial branches and the L5 dorsal rami. During the normal course of TLI, untrue and final true lateral segmental images were obtained and saved. An original data set of 100 pairs of true and untrue lateral images was reviewed to verify true laterality using established criteria; disagreement was resolved by consensus or discarding ambiguous cases. To measure interobserver reliability (Cohen's Kappa), two blinded expert reviewers independently reviewed the image set, identifying the true lateral image and the plane requiring correction.

Results

The observers agreed upon 98/98 true lateral RF-segment images (Kappa score 1.0 [1.00,1.00]). The observers agreed upon 86/98 maneuvers to correct the untrue RF-segment image. The Kappa score for determining the most appropriate corrective maneuver was 0.76 (0.63,0.89), showing substantial interobserver agreement.

Conclusions

The true lateral image of the targeted RF segment during LMBRFN was reliably determined with perfect interobserver agreement. Interobserver agreement was substantial regarding the maneuver to achieve TLI.

Background

This prospective longitudinal study compares outcomes for Medicare beneficiaries receiving outpatient percutaneous image-guided lumbar decompression (PILD) using the mild® procedure to patients undergoing outpatient laminectomy. All patients were diagnosed with lumbar spinal stenosis (LSS) with neurogenic claudication (NC).

Methods

All medical claims for 100 % of Medicare beneficiaries were reviewed, with study subjects identified using Centers for Medicare and Medicaid Research Identifiable Files. Baseline data were extracted individually to allow for longitudinal analysis through two-year follow-up. The index procedure was defined as the first mild or outpatient laminectomy during the enrollment period. The rate of subsequent surgical procedures and incidence of harms were used as study outcomes.

Results

Cohorts included 2197 mild and 7416 laminectomy patients. mild patients were significantly older (76.7 years versus 73.4 years, respectively; p < 0.0001), and 57.4 % of mild were female, compared to 43.3 % of laminectomy (p < 0.0001). mild patients presented with significantly more baseline comorbidities compared to laminectomy patients (mean of 5.7 versus 4.8, respectively; p < 0.0001). Subsequent surgical procedure rate of 9.0 % for mild was significantly higher than 5.5 % for laminectomy (p < 0.0001). mild experienced harms at a significantly lower rate than laminectomy (1.9 % versus 5.8 %, respectively; p < 0.0001). The composite rate of subsequent surgical procedures and harms was similar between groups at 10.8 % for mild and 11.0 % for laminectomy.

Conclusions

mild can be considered a viable option for treatment of LSS with NC as evidenced by real-world data in this study. At two-years, mild patients experienced fewer harms and underwent more subsequent surgical procedures than laminectomy patients. The higher rate of subsequent surgical procedures for mild may be attributable to its position earlier in the LSS treatment algorithm. The overall rate of harms and subsequent surgical procedures was similar between groups, suggesting that mild should be considered as a treatment option, particularly for older patients with multiple comorbidities.

Background

Lumbar radiofrequency neurotomy (LRFN) effectively alleviates zygapophyseal joint-mediated pain by coagulating medial branch nerves to disrupt nociceptive signaling pathways. The concomitant denervation of multifidus fibers has led to concern that LRFN may increase segmental instability and accelerate degenerative changes in patients with certain pre-existing spinal pathologies. There is a paucity of literature evaluating whether LRFN increases the progression of spinal curvature in patients with adult scoliosis.

Objective

Compare the lumbosacral Cobb angle progression rate in patients with adult scoliosis who underwent LRFN to the annual progression rate of 0.83 ± 1.1° expected by natural history.

Design

Cross-sectional study.

Methods

Consecutive patients diagnosed with adult scoliosis who underwent LRFN to treat zygapophyseal joint-related low back pain were identified. Patient demographics, LRFN procedure details, and radiographs confirming scoliosis were collected from electronic medical records. Pre- and post-LRFN radiographs were used to calculate the average annual rate of Cobb angle progression. Data were analyzed using a Wilcoxon signed-rank test and a linear regression model.

Results

Sixty patients (mean age 69.2 ± 11.6 years; 70.0 % female) met the criteria and were included in the analyses. The mean time to radiographic follow-up was 35.0 ± 22.7 months post-LRFN. The average Cobb angle progression was 0.54 ± 3.03° per year and did not differ significantly from the known natural progression rate of 0.83 ± 1.1° per year. None of the included covariates (body mass index, LRFN laterality, and number of levels denervated) were significantly associated with the average annual Cobb angle progression rate.

Conclusions

Our results suggest that LRFN has no appreciable effect on the rate of Cobb angle progression in patients with adult scoliosis.

Introduction

Cervical medial branch radiofrequency ablation is an effective treatment for cervical facet joint pain. It is considered a safe procedure, and permanent complications are very rare. We report a case of a patient who developed dropped-head syndrome (DHS) after bilateral treatment.

Case report

An 86-year-old man was referred to our pain clinic because of neck pain. One year before, he underwent bilateral multi-level cervical medial branch radiofrequency ablation. Within the next 24 hours, he experienced progressive neck extensor muscle weakness. After a comprehensive examination, he was diagnosed with dropped head syndrome as a complication of the radiofrequency procedure. Conservative management was chosen, resulting in partial improvement of the muscular weakness.

Conclusion

The present case, along with others reviewed in this article, supports the recommendation against performing bilateral and multilevel cervical medial branch radiofrequency ablation.

Introduction

Myofascial pain syndrome is a chronic pain condition prevalent in the general population. Muscular symptoms at the level of the trapezius and rhomboid muscles are frequent and the response to therapeutic interventions established so far is variable.

Methods

We present a case series of six patients who underwent a new technique of interfacial trapezius-rhomboid block (TRB) performed under ultrasonographic guidance by applying 10 cubic centimeters (cc) of analgesic solution (bupivacaine 0.25 % and methylprednisolone 40 mg) in the interfacial plane between the trapezius and rhomboid muscles at the level of the fifth and sixth ribs.

Results

At a follow-up of one and eight weeks, measurements of numerical rating scale (NRS) pain intensity were carried out, finding an average decrease of NRS pain intensity by 70 %.

Conclusion

This new technique may be considered for the treatment of myofascial pain syndrome of the trapezius and rhomboid muscles. Larger future studies are needed to better establish its safety and efficacy.

This series of FactFinders presents a brief summary of the evidence and outlines recommendations to improve our understanding and management of potential procedure-related complications.

Evidence in support of the following facts is presented. (1) Epidural Steroid injections for Radicular Pain Due to Spinal Stenosis Caused by Lipomatosis -- There is low-level evidence of an association between epidural steroid injections (ESIs) and the development and/or worsening of spinal epidural lipomatosis (SEL). However, there is insufficient evidence to establish whether ESIs independently result in an increase in spinal stenosis with neurological compromise in individuals with pre-existing SEL. (2) Steroid Exposure Postpartum -- There is no absolute contraindication to steroid injections based on postpartum or lactating status, but there may be disruption of both maternal and breastfed child hypothalamic-pituitary-adrenal (HPA) axis response to steroid administration. For the duration of breastfeeding, milk production may be affected after steroid exposure, and withholding breast milk produced for several hours after exposure minimizes infant exposure.

Background

Genicular radiofrequency neurotomy (GRFN) is an effective treatment for a subset of individuals with chronic knee pain. Previous studies demonstrate that Medicare and Medicaid beneficiaries report worse outcomes following various interventional procedures compared with commercially insured patients.

Objective

Evaluate the association of payer type on GRFN treatment outcomes.

Methods

Consecutive patients who underwent GRFN at a tertiary academic center were contacted for participation. Demographic, clinical, and procedural characteristics were collected from electronic medical records. Outcome data were collected by standardized telephone survey at 6–12 months, 12–24 months and ≥24 months. Treatment success was defined as ≥50% numerical pain rating scale (NPRS) score reduction from baseline. Data were analyzed using descriptive statistics for demographic, clinical, and procedural characteristics. Logistic and Poisson regression analyses were performed to examine the association of variables of interest and pain reduction.

Results

One hundred thirty-four patients treated with GRFN (mean 65.6 ± 12.7 years of age, 59.7% female) with a mean follow-up time of 23.3 ± 11.3 months were included. Payer type composition was 48.5% commercial (n = 65), 45.5% Medicare (n = 61), 3.7% Medicaid (n = 5), 1.5% government (n = 2), and 0.8% self-pay (n = 1). Overall, 47.8% of patients (n = 64) reported ≥50% NPRS score reduction after GRFN. After adjusting for age, follow-up duration, Kellgren-Lawrence osteoarthritis grade, baseline opioid use, antidepressant/antianxiety medication use, history of knee replacement, and number of RFN lesions placed, the logistic regression model showed no statically significant association between payer type and treatment outcome (OR = 2.11; 95% CI = 0.87, 5.11; p = 0.098).

Discussion/conclusion

In this study, after adjusting for demographic, clinical, and procedural characteristics, we found no association between payer type and treatment success following GRFN. This observation contrasts findings from other interventional studies reporting an association between payer category and treatment success.

Summary of background data

Low back pain of disc origin is common yet challenging to treat. Intradiscal platelet rich plasma (PRP) has been advocated, but is associated with risk of discitis. Epidural PRP is less invasive and avoids this risk. Few studies exist evaluating effectiveness and safety of epidural PRP for discogenic low back pain without radiculopathy and the follow-up of the studies tends to be short.

Objective

prospectively evaluate for 12 months the effectiveness of PRP epidural injections for patients with low back pain without radiculopathy, suspected to be of disc origin.

Methods

11 consecutive patients with refractory low back pain suspected to be of disc origin (compatible clinical assessment; negative lumbosacral medial branch blocks (MBBs) and/or magnetic resonance imaging (MRI) with high intensity zone (HIZ), Modic 1 or 2 changes) participated. Each underwent one (n = 5) or two (n = 6) epidural injections (caudal or interlaminar). The PRP was leukocyte/red cell depleted with an average platelet concentration of ∼2X whole blood. Numerical rating scale (NRS), Pain Disability Quality-Of-Life Questionnaire (PDQQ) score, Oswestry Disability Index (ODI) score, effect on analgesic intake, treatment satisfaction and endorsement were recorded prior to and at 3, 6 and 12-months post-treatment.

Results

significant improvements in pain and disability were documented post-treatment. Pre-, 3, 6, and 12-month post mean(sd) NRS scores were 7.8(1.8), 5.8(2.7), 5.1(2.5), 4.9(2.8) respectively (F = 7.2; p = 0.002). At 12 months post PRP epidural, the mean improvement in NRS was 36%, 36% had experienced ≥50% pain relief (95% confidence interval (CI): 2%, 70%), and 73% achieved minimal clinically important differences (MCID) (95% CI: 41%, 100%). Similar magnitude improvements in disability (PDQQ and ODI) were documented. At 1-year post, 50% of analgesic users had reduced intake, 91% were satisfied with the treatment and would recommend the procedure to family and friends. No complications were reported.

Discussions/conclusion

this pilot project suggests that PRP epidural injections provide modest yet significant improvements in pain and disability that lasts at least 12 months in patients with low back pain suspected to be of disc origin. Additional research including larger sample size and robust study design is encouraged.