Spinal cord stimulation with implanted epidural paddle lead relieves chronic axial low back pain

Bioelectronics for electrical stimulation: materials, devices and biomedical applications

Bioelectronics is a hot research topic, yet an important tool, as it facilitates the creation of advanced medical devices that interact with biological systems to effectively diagnose, monitor and treat a broad spectrum of health conditions. Electrical stimulation (ES) is a pivotal technique in bioelectronics, offering a precise, non-pharmacological means to modulate and control biological processes across molecular, cellular, tissue, and organ levels. This method holds the potential to restore or enhance physiological functions compromised by diseases or injuries by integrating sophisticated electrical signals, device interfaces, and designs tailored to specific biological mechanisms. This review explains the mechanisms by which ES influences cellular behaviors, introduces the essential stimulation principles, discusses the performance requirements for optimal ES systems, and highlights the representative applications. From this review, we can realize the potential of ES based bioelectronics in therapy, regenerative medicine and rehabilitation engineering technologies, ranging from tissue engineering to neurological technologies, and the modulation of cardiovascular and cognitive functions. This review underscores the versatility of ES in various biomedical contexts and emphasizes the need to adapt to complex biological and clinical landscapes it addresses.

Rates and Causes of Reoperations Following Spinal Cord Stimulation Within a 2-12 year Period

STUDY DESIGN

Retrospective study.

OBJECTIVE

Spinal cord stimulation has been mainly used for the management of postsurgical persistent neuropathic. The purpose of the study was to evaluate the rate and causes for reoperation following spinal cord stimulation, and to identify risk factors for reoperation.

METHODS

A retrospective study was conducted including patients who underwent surgical implantation of spinal cord stimulators within a 10-year period. The medical records of the included patients were reviewed for reoperations, demographics and certain clinical parameters. Demographics and clinical parameters were compared between patients with and without reoperations, and between patients with and without surgical site infections.

RESULTS

Overall, 1014 index procedures and 175 reoperations were performed within the study period. At least 1 reoperation was performed in 97 (9.5%) cases. The most common cause for revision was lead migration or lead misplacement (n = 31, 3.0%). In 31 (3.1%) cases the stimulator was removed due to no pain relief. Surgical site infection that required reoperation developed in 30 cases (2.9%). Younger age was associated with a need for reoperation (Odds Ratio [OR]: .97,95% Confidence Interval [CI]:0.95-.99, P = .005), while higher Body Mass index and diabetes were associated with development of infection (OR: 1.05, 95% CI: 1.00-1.11, P = .036 and OR: 2.42, 95% CI: 1.05-5.47, P = .033 respectively).

CONCLUSIONS

The results of this study indicate that certain measures could improve the overall reoperation rate after spinal cord stimulation, such as accurate positioning of the spinal cord stimulators and design of smaller generators. Moreover, preoperative optimization of patients could result in lower complication rate, lower reoperations rate, and subsequently better clinical outcomes.

Updates on the Role of Spinal Cord Stimulation in the Management of Non-Surgical Chronic Lower Back Pain

Studies have shown that spinal cord stimulation (SCS) therapy is effective in the management of chronic low back pain. It plays a role by minimizing the intensity of chronic pain, improving the quality of life index, reducing the intake of narcotic analgesics, and increasing the functional improvement in the working environment. However, spinal cord stimulation therapy is not universal because of the complications in the procedure itself, the invasive nature of the treatment, and cost-effectiveness. Therefore, the proper selection of the patients is necessary to get the maximum benefit from the treatment. The study's main objective is to determine the role of spinal cord stimulation in treating non-surgical patients with chronic low back pain. The article will review the mechanism, outcomes, efficacy, predisposing factors in the success and failure of the treatment and indications, contraindications, and selection of patients undergoing spinal cord stimulation therapy. A manual search of the literature was done using databases like Google Scholar and PubMed using the keywords: spinal cord, stimulation, chronic, and low back pain. A total of 37 articles were included in the study after considering the inclusion and exclusion criteria. Spinal cord stimulation therapy effectively treats refractory lower back pain, considering the technology and mechanism of action. The authors conclude that spinal cord stimulation therapy can be used to manage chronic low back pain, other neuropathic pain, and ischemic pain when other standard treatment methods have failed and the pain persisted for more than six months.

A wireless spinal stimulation system for ventral activation of the rat cervical spinal cord

Electrical stimulation of the cervical spinal cord is gaining traction as a therapy following spinal cord injury; however, it is difficult to target the cervical motor region in a rodent using a non-penetrating stimulus compared with direct placement of intraspinal wire electrodes. Penetrating wire electrodes have been explored in rodent and pig models and, while they have proven beneficial in the injured spinal cord, the negative aspects of spinal parenchymal penetration (e.g., gliosis, neural tissue damage, and obdurate inflammation) are of concern when considering therapeutic potential. We therefore designed a novel approach for epidural stimulation of the rat spinal cord using a wireless stimulation system and ventral electrode array. Our approach allowed for preservation of mobility following surgery and was suitable for long term stimulation strategies in awake, freely functioning animals. Further, electrophysiology mapping of the ventral spinal cord revealed the ventral approach was suitable to target muscle groups of the rat forelimb and, at a single electrode lead position, different stimulation protocols could be applied to achieve unique activation patterns of the muscles of the forelimb.

Electronics with shape actuation for minimally invasive spinal cord stimulation

Spinal cord stimulation is one of the oldest and most established neuromodulation therapies. However, today, clinicians need to choose between bulky paddle-type devices, requiring invasive surgery under general anesthetic, and percutaneous lead-type devices, which can be implanted via simple needle puncture under local anesthetic but offer clinical drawbacks when compared with paddle devices. By applying photo- and soft lithography fabrication, we have developed a device that features thin, flexible electronics and integrated fluidic channels. This device can be rolled up into the shape of a standard percutaneous needle then implanted on the site of interest before being expanded in situ, unfurling into its paddle-type conformation. The device and implantation procedure have been validated in vitro and on human cadaver models. This device paves the way for shape-changing bioelectronic devices that offer a large footprint for sensing or stimulation but are implanted in patients percutaneously in a minimally invasive fashion.

Successful Treatment of Chronic Back and Leg Pain With Lower Than Usual Placement of High-Frequency Spinal Cord Stimulation in a Patient With Uncorrected Tethered Cord: Case Report

BACKGROUND AND IMPORTANCE

Tethered cord syndrome (TCS) often leads to severe back and leg pain. The typical treatment to stall disease progression is untethering surgery, but this is not always effective for pain. Spinal cord stimulation (SCS) is an efficacious treatment for neuropathic pain. However, it has seldom been utilized in TCS cases. Moreover, with cord elongation, ideal paddle placement is not certain.

CLINICAL PRESENTATION

We present the case of a 77-yr-old male with severe chronic lower-back and lower-extremity pain. Magnetic resonance imaging (MRI) showed severe lumbar spine degenerative changes, along with a previously undiagnosed spina bifida and conus medullaris termination at L5. We felt that SCS would be the best treatment avenue for his chief complaint of pain. Due to cord elongation, we trialed lower placement of the high-frequency (HF)-SCS system at T11-T12, which led to 80% improvement in pain symptoms within 1 wk and ability to walk for the first time in a year. At his first follow-up appointment, the patient endorsed 80% to 90% relief of his lower-back and bilateral lower-extremity pain, which improved to 100% relief at 12 mo at last visit.

CONCLUSION

Only 4 other reports were identified in the literature utilizing SCS in TCS cases. Our case adds to the limited body of literature that SCS is an effective therapy for pain in TCS and degenerative spine disease. Only 2 other reports employed lower than usual lead placement. Our case demonstrates that lead placement may need to be changed to accommodate the elongated cord.

Neural Stimulation and Molecular Mechanisms of Plasticity and Regeneration: A Review

Neural stimulation modulates the depolarization of neurons, thereby triggering activity-associated mechanisms of neuronal plasticity. Activity-associated mechanisms in turn play a major role in post-mitotic structure and function of adult neurons. Our understanding of the interactions between neuronal behavior, patterns of neural activity, and the surrounding environment is evolving at a rapid pace. Brain derived neurotrophic factor is a critical mediator of activity-associated plasticity, while multiple immediate early genes mediate plasticity of neurons following bouts of neural activity. New research has uncovered genetic mechanisms that govern the expression of DNA following changes in neural activity patterns, including RNAPII pause-release and activity-associated double stranded breaks. Discovery of novel mechanisms governing activity-associated plasticity of neurons hints at a layered and complex molecular control of neuronal response to depolarization. Importantly, patterns of depolarization in neurons are shown to be important mediators of genetic expression patterns and molecular responses. More research is needed to fully uncover the molecular response of different types of neurons-to-activity patterns; however, known responses might be leveraged to facilitate recovery after neural damage. Physical rehabilitation through passive or active exercise modulates neurotrophic factor expression in the brain and spinal cord and can initiate cortical plasticity commensurate with functional recovery. Rehabilitation likely relies on activity-associated mechanisms; however, it may be limited in its application. Electrical and magnetic stimulation direct specific activity patterns not accessible through passive or active exercise and work synergistically to improve standing, walking, and forelimb use after injury. Here, we review emerging concepts in the molecular mechanisms of activity-derived plasticity in order to highlight opportunities that could add value to therapeutic protocols for promoting recovery of function after trauma, disease, or age-related functional decline.

Immediate Abdominal Pain after Placement of Thoracic Paddle Leads for Spinal Cord Stimulation: A Case Series

BACKGROUND

Spinal cord stimulation (SCS) is a well-established treatment modality for chronic pain. Thoracic radiculopathy has been reported as a complication of SCS paddle lead implantation by several authors and commonly presents as abdominal pain.

METHODS

We performed a search of all patients who underwent either placement of a new epidural paddle lead electrode or revision of an epidural paddle lead electrode for SCS in the thoracic region from January 2017 to January 2018. We then investigated all cases of immediate postoperative abdominal pain.

RESULTS

We identified 7 patients who had immediate postoperative abdominal pain among 86 cases of epidural SCS procedures. Most patients were discharged on postoperative days 1-3. No patients required revisions or removals of their SCS for any reason.

CONCLUSIONS

We conclude that the etiology of immediate postoperative abdominal pain after thoracic paddle lead implantation for SCS is most likely thoracic radiculopathy. We hypothesize that small, transient epidural hematomas could be the cause of this thoracic radiculopathy. We argue that all patients with immediate postoperative abdominal pain and no other neurologic deficits after thoracic paddle lead implantation for SCS should first be treated conservatively with observation and pain management.

Stimulation of the L2-L3 Dorsal Root Ganglia Induces Effective Pain Relief in the Low Back

INTRODUCTION

Chronic low back pain affects millions of people worldwide and can arise through a variety of clinical origins. In the case of failed back surgery syndrome (FBSS), previous surgical procedures can contribute to low back pain that is often unresponsive to intervention. Although spinal cord stimulation (SCS) can be an effective treatment modality, it does not provide sufficient pain relief for some intractable cases. Recently, alternative neuromodulation options have been developed, including dorsal root ganglion (DRG) stimulation. The objective of this report is to further investigate these clinical observations.

METHODS

Twelve patients with significant chronic discogenic low back pain due to FBSS were included. All subjects underwent implantation of DRG stimulation systems that had at least 1 lead placed at L2 or L3. Subjects' pain ratings, mood, and quality of life were tracked prospectively for up to 12 months.

RESULTS

More than half of subjects reported 50% or better pain relief in the low back, and the average low back pain relief was 45.5% at 12 months. Concomitant reductions in overall pain, leg pain, pain interference, mood, and quality of life were also found.

DISCUSSION

For the studied population, DRG stimulation at the L2-L3 levels was effective at relieving low back pain. These reductions in pain were associated with improvements in quality of life. Thus, DRG stimulation at these levels may be effective for low back pain by recruiting both segmental and nonsegmental neural pathways that are not otherwise accessible via traditional SCS.

Use of Spinal Cord Stimulation in Elderly Patients with Multi-Factorial Chronic Lumbar and Non-Radicular Lower Extremity Pain

Spinal cord stimulation (SCS) is an effective treatment for chronic back and limb pain. The criteria for use of SCS for specific problems such as failed back surgery syndrome (FBSS), peripheral neuropathic pain and residual pain after joint replacement is well established. With an aging population, there are more patients presenting with a combination of various multi-factorial chronic pain problems rather than from a single clear cause. It is not uncommon to see patients with chronic back pain years after spine surgery with new additional pain in the area of joint replacement or due to peripheral neuropathy. In most of these patients, one area is the primary cause of their pain, while the other more secondary. Multiple chronic problems complicate the pain management of the primary cause and also can diminish the effect of SCS that only targets the primary problem. The primary and secondary causes of pain were ranked by the patient including the duration of their chronic pain for each area. This helped establish criteria for use of SCS in these complex pain patients. The patients were evaluated initially with an epidural stimulator trial and if they obtained 50% or greater pain relief to the primary pain generating area, permanent implantation of one or more arrays of spinal cord electrodes was performed but planned to cover also the secondary pain areas. Post-implant follow-up evaluation at one, three and six months included measurement of visual analog scale (VAS), use of pain medication and degree of functional activity and behavior. This report looks at the effectiveness of using multiple overlapping electrodes for SCS in patients with multi-factorial chronic pain.

Rate of Complications Following Spinal Cord Stimulation Paddle Electrode Removal

OBJECTIVE

Spinal cord stimulation (SCS) is a safe, reversible surgical treatment for complex regional pain syndrome and failed back surgery syndrome refractory to conventional medical management. Paddle electrodes are routinely used for the permanent implant because of the reduced risk of migration, lower energy requirements, and expanded coverage options. The risks associated with paddle lead removal are not well defined in the literature.

METHODS

We retrospectively reviewed the outcomes of all patients at the Cleveland Clinic who underwent removal of SCS paddle electrodes between 2009 and 2016.

RESULTS

We identified 68 patients during this interval who had a paddle electrode removed. The most common reason for removal was loss of coverage or effect (75%), followed by infection (13.24%), and the need for magnetic resonance imaging for diagnostic purposes (8.82%). Postoperative complications occurred in eight patients (11.75%), two of which were classified as major (2.94%). One of these patients developed a postoperative cerebrospinal fluid leak, and another suffered a large suprafascial hematoma. Both patients underwent reoperation. Minor complications were reported in six patients (8.82%) and included wound dehiscence, infection, and prolonged ileus in one case. On average, patients who developed complications lost 20 mL more blood during surgery than those who did not develop complications (p = 0.006).

CONCLUSION

One of the benefits of SCS therapy is the reversibility of the procedure. However, removal is not without some risk though the overall risk of minor or major complication is low. Patients who are considering removal should be counseled appropriately. Prophylactic removal is not recommended. However, when removal is needed, surgeons and pain specialists must be familiar with these complications and their management.

Chiropractic management of post spinal cord stimulator spine pain: a case report

Background

A brief overview of failed back surgery syndrome, with emphasis on low back pain status post spinal cord stimulation, and post-surgical spinal manipulation is presented.

Case Presentation

Four cases of patients within the VA Connecticut Health Care System presenting between July 2014 and July 2015 reporting low back pain after surgical insertion of spinal cord stimulators are discussed. This study describes the outcomes experienced by four patients with low back pain status post implanted spinal cord stimulators receiving manual therapy in the form of lumbar spine manipulation or mobilization.

Conclusion

All four patients denied adverse effects to spinal manipulation/mobilization and onset of new symptoms after treatment; two patients reported durable reduction in low back pain with increased tolerance to walking, standing, or lying down, one reported temporary relief of low back pain, and one reported no change in symptoms. Further investigation is needed to determine the benefit of spinal manipulation in patients with implanted spinal cord stimulators, but this study has shown the absence of adverse effects from manipulation or mobilization treatment, in regards to SCS.

Are there a guidelines for implantable spinal cord stimulator therapy in patients using chronic anticoagulation therapy? - A review of decision-making in the high-risk patient

BACKGROUND

Spinal cord stimulators (SCSs) are gaining increasing indications and utility in an expanding variety of clinical conditions. Complications and initial expenses have historically prevented the early use of SCS therapy despite ongoing efforts to educate and promote its utilization. At present, there exists no literature evidence of SCS implantation in a chronically anticoagulated patient, and neuromodulation manufacturers are conspicuously silent in providing warnings or recommendations in the face of anticoagulant use chronically. It would appear as through these issues demand scrutiny and industry as well as neuromodulation society advocacy and support in terms of the provision of coherent guidelines on how to proceed.

CASE DESCRIPTION

A 79-year-old male returned to the neurosurgical clinic with persistent low back pain and leg heaviness due to adjacent level degenerative spondylosis and severe thoracic spinal stenosis. The patient had a notable history of multiple comorbidities along with atrial fibrillation requiring chronic anticoagulation. On initial presentation, he was educated with three choice of conservative medical therapy, intrathecal drug delivery system implantation, or additional lumbar decompression laminectomy with instrumented fusion of T10-L3 and a palliative surgical lead SCS implantation.

DESCRIPTION

A 79-year-old male returned to the neurosurgical clinic with persistent low back pain and leg heaviness due to adjacent level degenerative spondylosis and severe thoracic spinal stenosis. The patient had a notable history of multiple comorbidities along with atrial fibrillation requiring chronic anticoagulation. On initial presentation, he was educated with three choice of conservative medical therapy, intrathecal drug delivery system implantation, or additional lumbar decompression laminectomy with instrumented fusion of T10-L3 and a palliative surgical lead SCS implantation.

CONCLUSION

Our literature search did not reveal any evidence of SCS therapy among patients with chronic anticoagulation. This case illustrated a complicated clinical case scenario wherein a percutaneous SCS implantation would normally be contraindicated due to severe thoracic spinal stenosis and chronic anticoagulation which could lead to possible paralysis or even a lethal consequences associated with the possible formation of a thoracic epidural hematoma.

Integrated medical-psychiatric outpatient care in functional gastrointestinal disorders improves outcome: a pilot study

BACKGROUND AND OBJECTIVES

Functional gastrointestinal disorders have a multifactorial etiology, including somatic and psychosocial factors. We provide multidisciplinary outpatient consultations by a gastroenterologist and a psychiatrist using an integrated approach toward somatic and psychosocial factors in complex functional gastrointestinal disorders. The aim of this study was to determine the efficacy of this approach assessing gastrointestinal and psychiatric symptoms and quality of life.

METHODS

All patients with complex functional gastrointestinal disorders visiting for consultation were included and treated with antidepressants, psychotherapy, or both, or given advice for treatment in their own region. Questionnaires testing gastrointestinal and psychiatric symptoms, and quality of life at first visit and after 6 and 12 months were completed.

RESULTS

A total of 124 patients were included (70% women, mean age 48 years): 57% were diagnosed with irritable bowel syndrome and about 80% had a psychiatric diagnosis (50% anxiety disorder, 20% mood disorder). Of the patients, 57% were treated with antidepressants and psychotherapy, 6% with psychotherapy alone, and 38% received advice for treatment in their own region. After 1 year, patients showed significant improvement in all questionnaires, with the exception of those testing gastrointestinal symptoms, although there were significant improvements in these at 6 months.

CONCLUSION

This is the first prospective study on the efficacy of an integrated medical-psychiatric outpatient care model in patients with complex functional gastrointestinal disorders, showing significant improvement in gastrointestinal and psychiatric symptoms as well as quality of life after 6 months. With the exception of improvement in gastrointestinal symptoms, improvement persisted at the 1-year follow-up. This indicates that longer follow-up focusing on gastrointestinal symptoms may be needed.