Spinal Cord Stimulation and the Pregnant Patient‐Specific Considerations for Management: A Case Series and Review of the Literature

Objectives: The use of spinal cord stimulation (SCS) is a form of neuromodulation used to treat chronic pain in those patients who are refractory to conventional medical management. Not uncommonly, SCS can dramatically improve a patient's quality of life, and those who are in the childbearing years may go on to become pregnant. The purpose of this case series is to describe: 1) implantation considerations in women of childbearing age; 2) use of rechargeable systems; 3) the obstetric and anesthetic concerns in patients with spinal cord stimulators; 4) risks of using SCS in the peripartum period. Materials and Methods: Two female patients with complex regional pain syndrome I (CRPS I) who were well managed with SCS became pregnant. In both patients, the leads were placed through the T12/L1 interspace and the generator was placed in the buttock region. In the first patient, the device was deactivated prior to conception and maintained off for the duration of the pregnancy. The second patient became pregnant on two separate occasions, with active SCS for a portion of the first trimester. During her second pregnancy, the patient elected to use of SCS at 30 weeks' gestation. Results: The developing fetuses with intrauterine exposure to SCS were followed out for a minimum of two years and are developmentally normal. The physical presence of the device did not complicate obstetric or anesthetic care. Rechargeable SCS systems were not adversely affected when turned off for the duration of the pregnancy. Conclusion: Implantation of SCS devices in women of childbearing years should take into account the future needs of both obstetric and anesthetic care by avoiding the abdomen and lower lumbar spine whenever possible. There was no appreciable decline of battery capacity in present day constant current rechargeable generators when deactivated for the duration of pregnancy.     

Spinal Cord Stimulation in Pregnancy: A Literature Review

Objective: Currently, the use of spinal cord stimulation (SCS) therapy is not recommended in pregnancy because the effects of SCS on the pregnancy and developing fetus are unknown. However, many SCS recipients are women of childbearing age who may later become pregnant. The purpose of the present report is to review and summarize the existing literature on the use of SCS therapy during the prenatal period. Methods: We first present the case of a 38‐year‐old woman from our center who became pregnant after receiving an SCS implantation. We then provide a synopsis of previous reports that were identified in a literature search. We highlight the key findings from these cases as they relate to the course of pregnancy, fetal development, labor and delivery management, fertility, and technical complications. Results: In our literature review, we identified 12 cases of pregnancy in 8 women. To these we add the present case. Conclusions: Women of childbearing age who are candidates for SCS implantation should be tested for pregnancy prior to implantation surgery. They also should be informed about the limited state of our scientific knowledge regarding the impact of this technology on reproductive health. For patients already implanted with SCS, decisions about ongoing use in the event of pregnancy should be made on an individual basis after a careful consideration of potential risks and benefits.     

Burst Spinal Cord Stimulation in Pregnancy: First Clinical Experiences

ObjectivesSpinal cord stimulation (SCS) is a treatment for chronic neuropathic pain. It is based on the delivery of electric impulses to the spinal cord, traditionally in a regular square-wave pattern (“tonic” stimulation) and, more recently, in a rhythmic train-of-five “BurstDR” pattern. The safety of active SCS therapy in pregnancy is not established, and recommendations are based on limited casuistic evidence. We present in this study clinical data on a case series of six women treated with burst SCS during pregnancy. In addition, we present the ultrasonographic flow measurements of fetal and uteroplacental blood flow in a pregnant patient.Materials and MethodsPatients were included if they had been implanted with a full SCS system at Aarhus University Hospital, Denmark, between 2006 and 2020 and received active burst SCS stimulation during a pregnancy. Telephone interviews were conducted, including details on SCS therapy, medication, pregnancy course and outcome, and health status of the offspring. In one patient, the uteroplacental and fetal blood flow was assessed in gestational week 29 by Doppler flow measurements performed during both ON and OFF phases of the SCS system.ResultsSix patients were included with a total of 11 pregnancies. Three pregnancies ended in miscarriages, all in the same patient who had preexisting significant risk factors for miscarriage. Eight resulted in a live-born child with normal birth weight for gestational age; seven were born at term, and one was born late preterm, in gestational week 36. Ultrasonographic Doppler flow, measured in one patient, was normal and did not reveal any immediate changes between burst SCS ON and OFF. Seven children were reported healthy with normal neurodevelopment and one physically healthy but with developmental delays.ConclusionsThe data presented in this study add to the accumulating evidence of the safety of SCS in pregnancy.     

Systematic Literature Review of Spinal Cord Stimulation in Patients With Chronic Back Pain Without Prior Spine Surgery

ObjectiveLow back pain is the leading cause of disability worldwide and one of the most common reasons for seeking health care. Despite numerous care strategies, patients with low back pain continue to exhibit poor outcomes. Spinal cord stimulation (SCS) is an evidence-based therapeutic modality for patients with failed back surgery syndrome. For patients without a surgical lesion or history, minimally invasive interventions that provide long-term reduction of chronic back pain are needed. Therefore, we conducted a systematic review of the evidence on SCS therapy in patients with chronic back pain who have not undergone spinal surgery.Materials and MethodsA systematic literature search was performed to identify studies reporting outcomes for SCS in chronic back pain patients (with or without secondary radicular leg pain) without prior surgery using date limits from database inception to February 2021. Study results were analyzed and described qualitatively.ResultsA total of ten primary studies (16 publications) were included. The included studies consistently demonstrated favorable outcomes in terms of pain reduction and functional improvement following SCS therapy. Improvements also occurred in quality of life scores; however, not all studies reported statistically significant findings. Additionally, the studies reported that SCS resulted in high patient satisfaction, reductions in opioid use, and an acceptable safety profile, although these data were more limited.ConclusionFindings suggest that SCS is a promising, safe, minimally invasive, and reversible alternative option for managing chronic back pain in patients who have not undergone spinal surgery.     

Pregnancy, labor and delivery post spinal cord injury.

There are approximately 3,000 women of childbearing age who become spinal cord injured each year in the United States. There are few reports in the literature that address pregnancy, labor and delivery in this patient population. We are reporting on 22 women post spinal cord injury who had 33 pregnancies. There were equal numbers of paraplegic and quadriplegic women. Three pregnancies aborted, one spontaneously. The babies were near normal or normal weight with one exception. The mothers waited 5 years on average to become pregnant. Cesarean section was performed on 43% of pregnancies. Abnormal presentations occurred in over 10% of pregnancies. Indications for cesarean section included 5 that were repeats; the remainder were necessary due to bleeding (1), breech presentation (1), transverse presentation (2), lack of progress (2), onset of labor 1 day post spinal fusion, and a mother's request to have tubal ligation. Epidural anesthesia was selected for 9 deliveries; 6 of these patients had controlled autonomic hyperreflexia. Five general and 4 local anesthetics were used, and 12 patients received no anesthesia. Diagnostic ultrasound and amniocentesis were used selectively. Complications included autonomic hyperreflexia (9), frequent urinary tract infections, infected pressure sores (3, 2 resulting in below-knee amputations), seizures during and after delivery, pneumonia, bladder stones (2), episiotomy dehiscence (1), and breakdown of spinal fusion. The newborns were healthy, although one double footing breech vaginal delivery had an APGAR of 1 at 1 min, 7 at 5 min and 9 at 10 min. One premature baby, who weighed only 1600 g, was a precipitate birth at home unattended. Implications for the care of pregnant SCI women are discussed.     

Spinal Cord Stimulation for Intractable Visceral Pain due to Chronic Pancreatitis

Pain caused by chronic pancreatitis is medically intractable and resistant to conventional interventional or surgical treatment. We report a case of spinal cord stimulation (SCS) for intractable pain due to chronic pancreatitis. The patient had a history of nonalcoholic chronic pancreatitis and multiple emergency room visits as well as repeated hospitalization including multiple nerve block and morphine injection for 3 years. We implanted surgical lead at T6-8 level on this patient after successful trial of percutaneous electrode. The patient experienced a decreased visual analog scale (VAS) scores for pain intensity and amount of opioid intake. The patient was followed for more than 14 months with good outcome and no further hospitalization. From our clinical case, spinal cord stimulation on intractable pain due to chronic pancreatitis revealed moderate pain control outcome. We suggest that SCS is an effective, noninvasive treatment option for abdominal visceral pain. Further studies and long term follow-up are needed to fully understand the effect of SCS on abdominal visceral pain.     

The rational use of psychotropic drugs in pregnancy and postpartum

When a pregnant woman or nursing mother requires psychotropic medication, one must consider the effect of such medications on the fetus or baby. The authors review the evidence for teratogenic effects of such drugs given during pregnancy, toxic or withdrawal effects in the newborn and dangers to the breast-fed baby. Suggestions are made for judicious use of psychotropic drugs in pregnant or nursing women.     

Pregnancy related symptomatic vertebral hemangioma

Vertebral hemangiomas are benign vascular tumors of the spine that remain asymptomatic in most cases and incidentally encountered on imaging. Rarely, altered hemodynamic and hormonal changes during pregnancy may expand these benign lesions resulting in severe cord compression. The management of symptomatic vertebral hemangioma during pregnancy is controversial as modalities like radiotherapy and embolization are not suitable and surgery during pregnancy has a risk of preterm labor. Few cases of pregnancy related symptomatic vertebral hemangioma with marked epidural component have been reported in the literature. We report a case of 23-year-old primigravida who developed rapidly progressive paraparesis at 28 weeks of gestation and spine magnetic resonance imaging (MRI) revealed upper thoracic vertebral hemangioma with extensive extra-osseous extension and spinal cord compression. Laminectomy and surgical decompression of the cord was performed at 32 weeks of the pregnancy. There was significant improvement in muscle power after a week of surgery. Six weeks postoperatively she delivered a full term normal baby with subsequent improvement of neurologic deficit. Repeat MRI of dorsal spine performed at 3 months postoperatively showed reduced posterior and anterior epidural components of vertebral hemangioma.     

Spinal Stimulation for Pain: Future Applications

With continuous progress and rapid technological advancement of neuromodulation it is conceivable that within next decade or so, our approach to the electrical stimulation of the spinal cord used in treatment of chronic pain will change radically. The currently used spinal cord stimulation (SCS), with its procedural invasiveness, bulky devices, simplistic stimulation paradigms, and frustrating decline in effectiveness over time will be replaced by much more refined and individually tailored modality. Better understanding of underlying mechanism of action will allow us to use SCS in a more rational way, selecting patient-specific targets and techniques that properly fit each patient with chronic pain based on pain characteristics, distribution, and cause. Based on the information available today, this article will summarize emerging applications of SCS in the treatment of pain and theorize on further developments that may be introduced in the foreseeable future. An overview of clinical and technological innovations will serve as a basis for better understanding of SCS landscape for the next several years.     

Spinal Cord Stimulation in Conjunction With Peripheral Nerve Field Stimulation for the Treatment of Low Back and Leg Pain: A Case Series

Background. The treatment of chronic low back and leg pain remains a difficult medical challenge, particularly for patients with postlaminectomy syndrome. While spinal cord stimulation (SCS) has been a significant addition to the available options, it is often inadequate in relieving both the back and leg pain components. We hypothesized that for some patients the combination of SCS with peripheral nerve field stimulation (PNFS) would be a safe, effective alternative that would be more effective than either modality alone. Objective. Our objective was to demonstrate the efficacy of PNFS used in combination with SCS for the treatment of chronic pain syndromes involving the lower back and legs. Study Design. Case series. Methods. A total of 20 patients with chronic low back and leg pain syndromes who had failed conventional therapies underwent implantation of a combination of traditional SCS and PNFS. Leads were placed in the epidural space, as well as superficially in the subcutaneous tissues of the lower back, directly in the region of maximum pain. Patients initially underwent a trial of stimulation to assess response, and a permanent system was implanted if patients reported greater than 50% pain relief during the trial. For some patients, a combination was used at the time of the initial trial. In other cases, the decision to proceed with the combination was made later, either at the time of permanent implant, or later on, after SCS alone failed to adequately control pain. Results. In each case, PNFS was used in combination with traditional SCS for patients with chronic lower back and lower extremity pain. While not all of these patients ultimately proceeded with the combination of SCS and PNFS to control their pain, the majority of patients found the combination better in controlling their overall pain than either modality alone. In addition, using a combined approach at the time of trial provided a noninvasive and effective method of comparing the efficacy of each method, allowing patients to identify the best form of neuromodulation for their particular pain. Conclusions. Due to the availability of 16 contact capacity generators, neurostimulation with multiple leads in various combinations—including both epidural and peripheral nerve field stimulation simultaneously—can be applied safely and effectively. The availability of this combined approach for a trial of stimulation prior to implant allows patients to compare SCS to PNFS and to indicate a preference for one over the other or for the combination. We conclude that PNFS may be used in combination with SCS as a safe and effective alternative treatment for patients with chronic low back and leg pain, and further suggest that the combined approach should be considered as a treatment option for this population.     

Spinal Cord Stimulation in the First Two Trimesters of Pregnancy: Case Report and Review of the Literature

Introduction. Spinal cord stimulation (SCS) is an accepted cost‐effective therapy for many chronic pain syndromes. Its effects on pregnancy have not been studied because of stringent regulation and manufacturers' recommendations. However, childbearing women who had SCS become or choose to become pregnant despite these policies. It is paramount to monitor, document, and report these effects of SCS during pregnancy to build clinical experience and guide recommendations and management. Methods. We reviewed the literature for SCS in pregnancy and added new case report of a young woman who had SCS implanted for chronic pain, became pregnant and at the end of the second trimester the lead extender had to be divided to relief pain at the lead site. Results. We found only one previous case report in this field and we add another case. Discussion. Our case is different from the previously reported case in that the implantable pulse generator (IPG) of our case was implanted in the anterior abdominal wall, while the previously reported case was implanted in the subclavicular fossa. Therefore our case highlights the need to implant the IPG in a way that avoids stretching the lead extender by the expanding abdomen. Conclusion. SCS seems to be safe in the first two trimesters of pregnancy based on these two case reports and the abdominal wall should be avoided as a site for IPG implantation in these patients. However, more cases are required to establish the safety of SCS in pregnancy.     

Spinal Cord Stimulation Has Comparable Efficacy in Common Pain Etiologies

Objectives. The probability of success with spinal cord stimulation (SCS) depends largely on appropriate patient selection. Here, we have assessed the predictive value of pain etiology as it relates to pain relief with SCS as part of a prospective multicenter clinical trial. Methods. Sixty‐five subjects with chronic and intractable pain tested an epidural SCS system. Subjects reported pain ratings (visual analog scale) with stimulation off and stimulation on at scheduled follow‐up visits for up to 18 months after activation of the system. Visual analog scale scores were averaged and stratified by dominant pain etiologies, comprising failed back surgery syndrome, complex regional pain syndrome, and a subgroup of subjects with miscellaneous other pain etiologies. Results. More than 70% of subjects in each subgroup had successful outcomes during the temporary trial period and similar percentages of subjects from each etiology subgroup subsequently went on to permanent implantation. After permanent implantation, all subgroups reported more than 50% pain relief, on average, at each follow‐up time point. No predictive value of pain etiology was observed. Conclusions. Spinal cord stimulation is an effective therapy for neuropathic pain arising from a variety of causes. Failed back surgery syndrome, complex regional pain syndrome, and pain of other etiologies responded equally well to SCS.     

Abdominal Angina due to Obstruction of Mesenteric Artery Treated With Spinal Cord Stimulation: A Clinical Case

Introduction: Abdominal angina occurs in patients affected by mesenteric artery obstruction, causing postprandial episodes of visceral pain. The conventional treatment consists of vessels revascularization, but sometimes this is not applicable. Case Report: The authors report a case of a patient with severe abdominal angina caused by mesenteric ischemia, not treatable with surgery and few‐responder to pharmacological therapy (opioids and epidural infusion of local anesthetics). After a successful screening test, the patient underwent implantation of a spinal cord stimulation (SCS) device. Results: The stimulation provided a reduction in pain episodes (number and intensity) and in oral analgesics consumption. Results obtained support the clinical efficacy and durability of the SCS in the management of abdominal angina due to not treatable mesenteric ischemia. Conclusions: Spinal cord stimulation may be considered for abdominal angina, although there is still no evidence provided by controlled studies.     

A New and Alternative Leads Positioning for Complex Regional Pain Syndrome Treatment: Paraforaminal Stimulation

We present a case of a female patient suffering from type I complex regional pain syndrome (CRPS) who developed “mirror imaging” of her CRPS and was successfully treated with dual spinal cord stimulation (SCS) in the paraforaminal epidural space. This patient initially had unilateral pain that was unsuccessfully treated with midline SCS and single‐lead lateral epidural lead placement “paraforaminally.” One year later, because we believed that paraforaminal stimulation would preferentially stimulate primary sensitized afferents innervating the painful area, we reperformed SCS with two leads positioned laterally and paraforaminally close to the roots within the epidural space. After repositioning and after 1 year of paraforaminal stimulation, there was significant improvement in the patient's symptoms, resolving all unilateral and “mirrored” symptoms. We conclude that paraforaminal stimulation may be a valid therapeutic option for the treatment of CRPS.     

The effect of spinal cord stimulation in patients with chronic reflex sympathetic dystrophy: two years' follow-up of the randomized controlled trial

Chronic reflex sympathetic dystrophy is a painful, disabling disorder for which no treatment with proven effect is available. We performed a randomized trial in a 2 to 1 ratio of patients, in which 36 patients were treated with spinal cord stimulation and physical therapy (SCS+PT), and 18 patients received solely PT. Twenty-four SCS+PT patients were given a permanent spinal cord stimulation system after successful test stimulation; the remaining 12 patients received no permanent system. We assessed pain intensity, global perceived effect, functional status, and health-related quality of life. Patients were examined before randomization, before implantation, and also at 1, 3, 6, 12, and 24 months thereafter. At 2 years, three patients were excluded from the analysis. The intention-to-treat analysis showed improvements in the SCS+PT group concerning pain intensity (-2.1 vs 0.0 cm; p < 0.001) and global perceived effect (43% vs 6% "much improved"; p = 0.001). There was no clinically important improvement of functional status. Health-related quality of life improved only in the group receiving spinal cord stimulation. After careful selection and successful test stimulation, spinal cord stimulation results in a long-term pain reduction and health-related quality of life improvement in chronic reflex sympathetic dystrophy.     

Tripolar Spinal Cord Stimulation for the Treatment of Abdominal Pain Associated With Irritable Bowel Syndrome

Objectives: The objective of this case report is to describe the use of transverse tripolar dorsal column stimulation in a patient with a history of irritable bowel syndrome (IBS) associated with abdominal pain resistant to conservative treatments. Method: We report a 36‐year‐old man who presented to the pain clinic with an eight‐year history of IBS (constipation predominant with occasional diarrheal episodes), with “crampy and sharp” abdominal pain. He also had nonradicular thoracic spine pain due to thoracic scoliosis. Both pains were affecting his ability to function as an attorney. Prior conservative therapy, including psychologic treatment, antidepressants, and opioids, was without any benefits. Results: The use of a spinal cord stimulator (SCS) was discussed with the patient. The procedure was performed after Institutional Review Board approval. A tripolar SCS was implanted at the T8 level using one‐eight contact and two‐four contact percutaneous leads based on paresthesia reproduction of patient's areas of discomfort. This tripolar spinal cord stimulation provided relief of abdominal and thoracic pain, and better management of gastrointestinal symptoms. The patient was followed‐up for one year, and his quality of life also was improved via the IBS‐Severity Scoring System quality of life tool. Conclusions: The use of the tripolar SCS in this patient provided relief of abdominal and thoracic spine pain, regulated bowel habits, and improved the patient's quality of life. We believe that the use of SCS should be considered as a treatment option in patients with IBS when all conservative treatments failed.     

Efficacy of Peripheral Nerve Field Stimulation for the Management of Chronic Low Back Pain and Persistent Spinal Pain Syndrome: A Narrative Review

ObjectivesVarious approaches have been developed with a view to treating the back pain component in patients with chronic low back pain (CLBP) and persistent spinal pain syndrome (PSPS). Emerging evidence shows that peripheral nerve field stimulation (PNFS) may be an efficacious therapeutic modality against axial low back pain. Hence, the aim of the review was to evaluate the analgesic efficacy and safety of PNFS, when used alone or as an adjunct to spinal cord stimulation (SCS), for managing CLBP and PSPS.Materials and MethodsA comprehensive search for clinical studies on PNFS and PNFS + SCS used for the management of CLBP and/or PSPS was performed using PubMed, EMBASE, MEDLINE via Proquest, and Web of Science.ResultsA total of 15 studies were included, of which four were randomized controlled trials (RCTs), nine were observational studies, and two were case series. For patients receiving PNFS, a significant decrease in back pain intensity and analgesic consumption, together with a significant improvement in physical functioning, was observed upon implant of the permanent system. Meanwhile, the addition of PNFS to SCS in refractory cases was associated with a significant reduction in back and leg pain, respectively.ConclusionsThis review suggests that PNFS, when used alone or in combination with SCS, appears to be effective in managing back pain. However, high-quality evidence that supports the long-term analgesic efficacy and safety is still lacking. Hence, RCTs with a larger patient population and of a longer follow-up duration are warranted.     

中枢性疼痛的神经外科治疗

目的 研究中枢性疼痛的神经外科治疗策略.方法 根据疼痛性质和部位的不同,行立体定向中脑毁损术1例、双侧扣带回前部毁损术2例、中脑加双侧扣带回联合毁损术9例、运动皮层电刺激术(MCS) 11例、脊髓电刺激术(SCS)3例和脊髓后根入髓区(DREZ)切开术79例次.结果 术后患者疼痛均不同程度减轻,1个月以内镇痛疗效满意,VAS评分较术前均显著降低(P＜0.01).随访12 -36个月,观察术后6个月以上的长期疗效,发现中脑加双侧扣带回联合毁损术好于单纯中脑或扣带回前部毁损术的效果;MCS和SCS治疗的多数患者疗效有波动;DREZ切开术的长期疗效满意,82.1％的臂丛神经撕脱后疼痛患者能够保持50％以上疼痛缓解率,88.9％的脊髓损伤后疼痛患者止痛疗效长期稳定.结论 神经外科止痛手术能够确实有效地治疗中枢性疼痛,脊髓损伤、脊神经根撕脱等脊髓水平的中枢性疼痛应该首选DREZ切开术治疗,对于脑梗死、脑出血等原因造成的中枢性疼痛,MCS是一种可供选择的治疗手段.     

High-Level Cervical Spinal Cord Stimulation Used to Treat Intractable Pain Arising from Transverse Myelitis Caused by Schistosomiasis

The efficacy of spinal cord stimulation (SCS) for treatment of various chronic painful conditions is well established. Very few reports have documented the use of SCS for treatment of chronic pain after spinal cord injury. We present a case showing a good outcome after such treatment, and suggest that high cervical stimulation may be efficacious. A 53-year-old male underwent SCS on the C1-3 level for treatment of intractable neuropathic pain below the T3 level, and in the upper extremities, arising from spinal cord injury resulting from transverse myelitis caused by schistosomiasis. High cervical SCS significantly improved the pain in the upper extremities and at the T3-T10 dermatome level. The patient continues to report excellent pain relief 9 months later. The present case suggests that high cervical stimulation may improve chronic pain in the upper extremities and the T3-T10 dermatome level arising from spinal cord injury.     

Spinal Cord Stimulation With Hybrid Lead Relieves Pain in Low Back and Legs

Objective: The failed back surgery syndrome (FBSS) is the most common chronic pain syndrome. Whereas it is relatively easy to achieve pain relief in the lower limbs of FBSS patients with spinal cord stimulation (SCS), it is difficult to manage low back pain with SCS. The performance of a paddle‐shaped SCS lead that can be inserted surgically as well as percutaneously (a hybrid lead) was evaluated in a prospective study on the relief of low back pain and leg pain in patients with FBSS. Materials and Methods: Patients with FBSS being eligible for SCS were enrolled in the study, and a hybrid lead was placed surgically. Outcome measures included pain scores for low back and leg pain assessed by visual analog scale (VAS), pain medication, and patient satisfaction. These scores were assessed before and at regular intervals after implantation. Results: It was shown that a single hybrid lead, generally positioned over the physiological midline of the spinal cord, is capable of alleviating both low back and leg pain in patients with FBSS. Forty‐five subjects were eligible for SCS and received trial stimulation. Forty‐two of them had a successful trial period and were converted to a permanent system. Their average VAS score at baseline was 8.0 for lower limb pain and 7.5 for low back pain. After six months of SCS, these average VAS scores were reduced to 3.2 and 3.5, respectively, and also pain medication was reduced significantly. Conclusion: SCS with a hybrid lead in subjects with FBSS is safe, and causes significant pain relief in both the low back and the lower limbs.