Spinal Cord Stimulation,Conception, Pregnancy,and Labor: Case Study in a Complex Regional Pain Syndrome Patient

Introduction. Interventional modalities for pain treatment are reserved for patients failing multidisciplinary pain management, including psychological, physical, pharmacological, and anesthetic techniques. Objective. Medications for intractable pain may be unacceptable because the risk of teratogenic effects. The purpose of this study is to find out whether spinal cord stimulation may be safe during conception, pregnancy, and delivery. Materials and Methods. We report a 30-year old, female, neonatal nurse who developed left hand burning pain, swelling, coldness, and weakness following a mild brachial plexus injury in a motor vehicle accident. The patient responded well to a combination of Neurontin, Trazadone, Ultram, and Vicodin. A year later, the patient married and wanted to become pregnant but was afraid of possible teratogenic effects of the medications. Therefore, she requested an interventional modality for control of her symptoms. We recommended spinal cord stimulation (SCS) based on our excellent experience with this modality in the management of complex regional pain syndromes (CRPS). However, we did inform the patient that no data had been published regarding the safety of this modality in pregnancy and labor. Results. Cervical SCS resulted in excellent pain control and discontinuation of the medications. Thirteen months later, she delivered a healthy five pound baby girl. Mother and baby were discharged home in two days. The SCS was not turned off at any time during the labor and delivery. Conclusion. SCS was safe for implantation in our case study of a pregnant woman. This may constitute a new indication for SCS in patients otherwise successfully managed with non-interventional modalities for pain control.     

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.     

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 as Alternative Treatment for Chronic Post‐Herniorrhaphy Pain

Objective: Our goal was to determine the efficacy of spinal cord stimulation for patients with intractable post‐herniorrhaphy pain which conventional treatment failed to ameliorate. Procedure: The patients underwent an uneventful spinal cord stimulator (SCS) trial with percutaneous placement of two eight‐electrode epidural leads (Medtronic Inc, Minneapolis, MN, USA) to level T7‐T8‐T9. Results: Upon experiencing excellent pain relief over the next two days during the trial, the patients were implanted with permanent leads and rechargeable or non‐rechargeable generators two to four weeks later and reported sustained pain relief during following 12 months after implantation. Conclusion: We conclude that SCS offers an alternative treatment option for intractable post‐herniorrhaphy pain. This type of treatment should be considered for use in a select group of patients when all conventional treatments failed.     

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.     

Peripheral Nerve Field Stimulation in the Treatment of Postlaminectomy Syndrome after Multilevel Spinal Surgeries

Introduction: Chronic low back pain in patients with postlaminectomy syndrome (PLS) is challenging to treat, especially for patients who have undergone multilevel surgical procedures. Despite conservative therapy and available interventional pain procedures including spinal cord stimulation (SCS) and intrathecal therapies, patients may continue with intractable low back pain. Peripheral nerve field stimulation (PNFS) may represent an effective alternative treatment option for these patients when conventional treatments do not provide adequate relief of intractable low back pain. Methods: Eighteen patients underwent an uneventful PNFS trial with percutaneous placement of four temporary quadripolar leads (Medtronic, Inc., Minneapolis, MN, USA) placed subcutaneously over the lumbar or thoraco‐lumbar area. Results: After experiencing excellent pain relief over the next two days, temporary leads were removed. The patients were implanted with permanent leads and rechargeable or non‐rechargeable generator two to four weeks after temporary lead removal. All patients reported sustained pain relief 12 months after implantation. Discussion: PNFS with use of four vertically orientated leads provides an effective treatment option for patients with PLS after multilevel surgical procedures with intractable low back pain who have failed conservative treatment. PNFS may provide pain relief with advantages over conservative treatments and interventional treatments including SCS and intrathecal therapy. Conclusion: PNFS may be more effective in treating intractable low back pain than SCS in patients with PLS after multilevel spinal surgeries.     

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.     

The Link Between Spinal Cord Stimulation and the Parasympathetic Nervous System in Patients With Failed Back Surgery Syndrome

ObjectivesIn patients with chronic pain, a relative lower parasympathetic activity is suggested based on heart rate variability measurements. It is hypothesized that spinal cord stimulation (SCS) is able to influence the autonomic nervous system. The aim of this study is to further explore the influence of SCS on the autonomic nervous system by evaluating whether SCS is able to influence skin conductance, blood volume pulse, heart rate, and respiration rate.Materials and MethodsTwenty-eight patients with Failed Back Surgery Syndrome (FBSS), who are being treated with SCS, took part in this multicenter study. Skin conductance and cardiorespiratory parameters (blood volume pulse, heart rate, and respiration rate) were measured during on and off states of SCS. Paired statistics were performed on a 5-min recording segment for all parameters.ResultsSCS significantly decreased back and leg pain intensity scores in patients with FBSS. Skin conductance level and blood volume pulse were not altered between on and off states of SCS. Heart rate and respiration rate significantly decreased when SCS was activated.ConclusionsParameters that are regulated by the sympathetic nervous system were not significantly different between SCS on and off states, leading to the hypothesis that SCS is capable of restoring the dysregulation of the autonomic nervous system by primarily increasing the activity of the parasympathetic system in patients with FBSS.     

Combined Spinal Cord and Peripheral Nerve Field Stimulation for Persistent Post‐Herniorrhaphy Pain

Objectives: Chronic post‐hernia pain is a common complication after inguinal herniorrhaphies. Peripheral nerve field stimulation (PNFS) and spinal cord stimulation (SCS) are two new promising treatment modalities. Four patients with persistent neuropathic post‐hernia pain were recruited for this prospective study. Materials and Methods: Electrodes were inserted into the epidural space of the spinal canal and into the subcutaneous tissue in the inguinal region during a single surgical procedure. During a 14‐day trial, double‐blind stimulation was performed via an external stimulator: three days using the spinal electrode (SCS), three days using the inguinal electrode (PNFS), three days using both (SCS + PNFS), and five days off, with an alternating order from patient to patient. During the trial, pain intensity was assessed thrice daily by the visual analog scale. Additionally, pain intensity and quality of life (QOL) were assessed before and after surgical intervention by the Brief Pain Inventory, SF36 scale, and Pain Disability Index. Results: All patients had a marked pain reduction during the trial phase, and this reduction was more prominent when both electrodes were activated simultaneously (p < 0.001). At the late follow‐up, a significant pain reduction and improvement of QOL was observed in three patients. Conclusions: Both SCS and PNFS are effective in treating post‐hernia pain, but the magnitude of pain reduction was more prominent with concomitant stimulation. Combined PNFS and SCS should be considered for patients with a less than optimal response to either SCS or PNFS. More studies are necessary to address the cost‐effect issues of this new approach to treatment.     

Treatment of Chronic Chest Wall Pain in a Patient With Loeys-Dietz Syndrome Using Spinal Cord Stimulation

Objective: Spinal cord stimulation (SCS) has been used with increased frequency for the treatment of intractable pain including chronic chest pain. Methods: The patient with a history of Loeys‐Dietz syndrome who underwent repair of pectus excavatum with subsequent chronic chest wall pain underwent an uneventful SCS trial with percutaneous epidural placement of two temporary eight‐electrode leads placed at the level of T3‐T4‐T5. Results: After experiencing excellent pain relief over the next two days, the patient was implanted with permanent leads and rechargeable generator four weeks later and reported sustained pain relief at 12‐month follow‐up visit. Conclusion: SCS provides an effective, alternative treatment option for select patients with Loeys‐Dietz syndrome who underwent repair of pectus excavatum with subsequent chronic chest wall pain who have failed conservative treatment. SCS may provide pain relief with advantages over conservative treatments and more invasive techniques.     

Evaluation of cervical stimulation for chronic treatment of spasticity

Electrical stimulation of the spinal cord (SCS) to reduce spasticity was evaluated in seven patients who, along with their physicians, perceived significant and prompt benefit from stimulation. In two 24-hour test periods, on or off stimulation, we used two independent methods of evaluation: quantitative measures of joint compliance and stretch reflexes, and a standardized neurologic examination. Neither method did better than chance in determining whether SCS was actually being received. Problems with the experimental protocol are discussed, but the results cannot be interpreted as supporting the efficacy of SCS as a treatment for spasticity.     

Spinal Cord Stimulation Versus Re-operation in Patients With Failed Back Surgery Syndrome: An International Multicenter Randomized Controlled Trial (EVIDENCE Study)

Objective: This paper presents the protocol of the EVIDENCE study, a multicenter multinational randomized controlled trial to assess the effectiveness and cost‐effectiveness of spinal cord stimulation (SCS) with rechargeable pulse generator versus re‐operation through 36‐month follow‐up in patients with failed back surgery syndrome. Study Design: Study subjects have neuropathic radicular leg pain exceeding or equaling any low back pain and meet specified entry criteria. One‐to‐one randomization is stratified by site and by one or more prior lumbosacral operations. The sample size of 132 subjects may be adjusted to between 100 and 200 subjects using a standard adaptive design statistical method with pre‐defined rules. Crossover treatment is possible. Co‐primary endpoints are proportion of subjects reporting ≥50% leg pain relief without crossover at 6 and at 24 months after SCS screening trial or re‐operation. Insufficient pain relief constitutes failure of randomized treatment, as does crossover. Secondary endpoints include cost‐effectiveness; relief of leg, back, and overall pain; change in disability and quality of life; and rate of crossover. We are collecting data on subject global impression of change, patient satisfaction with treatment, employment status, pain/paresthesia overlap, SCS programming, and adverse events. Discussion: As the first multicenter randomized controlled trial of SCS versus re‐operation and the first to use only rechargeable SCS pulse generators, the EVIDENCE study will provide up‐to‐date evidence on the treatment of failed back surgery syndrome.     

Generating artificial sensations with spinal cord stimulation in primates and rodents

For patients who have lost sensory function due to a neurological injury such as spinal cord injury (SCI), stroke, or amputation, spinal cord stimulation (SCS) may provide a mechanism for restoring somatic sensations via an intuitive, non-visual pathway. Inspired by this vision, here we trained rhesus monkeys and rats to detect and discriminate patterns of epidural SCS. Thereafter, we constructed psychometric curves describing the relationship between different SCS parameters and the animal's ability to detect SCS and/or changes in its characteristics. We found that the stimulus detection threshold decreased with higher frequency, longer pulse-width, and increasing duration of SCS. Moreover, we found that monkeys were able to discriminate temporally- and spatially-varying patterns (i.e. variations in frequency and location) of SCS delivered through multiple electrodes. Additionally, sensory discrimination of SCS-induced sensations in rats obeyed Weber's law of just-noticeable differences. These findings suggest that by varying SCS intensity, temporal pattern, and location different sensory experiences can be evoked. As such, we posit that SCS can provide intuitive sensory feedback in neuroprosthetic devices.     

Myasthenia gravis and pregnancy

Treatment considerations for women who have MG and are of childbearing age are complicated. When possible, before pregnancy, establishing a plan for therapy is ideal, recognizing the potential concerns for the patient and the fetus. Decisions about treatment during pregnancy must balance the potential complications for the fetus, the patient, and even the integrity of the pregnancy. Most women who have MG are able to complete pregnancy successfully and deliver a healthy baby; however, there always is some risk that NMG may occur. Pregnant patients who have MG are served best at centers capable of providing coordinated expert care from neurologic, obstetric, and pediatric providers.     

Multiple Program Spinal Cord Stimulation in the Treatment of Chronic Pain: Follow-Up of Multiple Program SCS

Objective. Follow-up of 80 patients using multiple program spinal cord stimulation (SCS). Methods. For 30 months, we followed 80 chronic pain patients who had undergone SCS implantations at our center. Thirty-six patients had Failed Back Surgery Syndrome (FBSS). Patients were evaluated in patient-controlled stimulation mode (patients can select one of several specific programs in response to their activities and pain level). We collected visual analog pain scores, patient satisfaction scores, pain maps, and paresthesia maps. Results. We previously reported our preliminary findings (Neuromodulation 1998;1 :30–45). At 24 months all patients were using more than one program. At 30 months, 62 patients (76%) were using more than two programs as their preferred stimulation mode and three patients (4%) were satisfied with only one stimulation program. At 30 months all patients chose patient-controlled stimulation as their preferred mode of stimulation. A total of 18 patients (23%) were explanted. Mean pain scores declined from 8.2 at baseline to 4.8 (p < 0.05, n= 79). Paresthesia overlap was 91% (n= 79). Of the patients with FBSS, 81% reported that they were using their SCS daily. Conclusions. In spinal cord stimulation the use of multiple electrodes and multiple stimulation programs, together with advanced programmability, increases paresthesia overlap, reduces pain scores, and may improve patient satisfaction with SCS therapy. This study indicates a significant patient preference for multiple program SCS, if patients are given the option to choose between a single program SCS system or a multiple program SCS system.     

Lumbar and Sacral Nerve Root Stimulation (NRS) in the Treatment of Chronic Pain: A Novel Anatomic Approach and Neuro Stimulation Technique

Objective. The conventional technique used to stimulate the lumbar dermatomes is by stimulation of the dorsal columns of the spinal cord. Until recently, stimulation of nerve roots had not been successfully accomplished. We had performed selective nerve root cannulations for the placement of temporary catheters at cervical, thoracic, lumbar, and sacral levels in chronic pain patients using a caudad rather than craniad approach. We hypothesized that by stimulating the nerve roots we could improve paresthesia coverage in areas which cannot be covered effectively by spinal cord stimulation (SCS). To test this hypothesis, we have performed trials of nerve root stimulation (NRS) in patients who had failed SCS, or who were not candidates for SCS because their pain was otherwise inaccessible to stimulation. Methods. Five patients who had been unresponsive to conservative treatment, surgery, or SCS underwent 7-day trials with NRS. The diagnoses included: ilioinguinal neuralgia, discogenic low back pain, failed back syndrome, vulvodynia, and interstitial cystitis. We collected paresthesia maps, pain maps, pain visual analog scale (VAS) scores, and patient satisfaction ratings. Results. Paresthesia coverage was above 75% in all patients. VAS scores declined from a mean of 9 ± 1.0 to 2.4 ± 2.1 (p < 0.05, n= 5), all 5 patients requested permanent implantation, and 4 have been implanted so far. Conclusions. Lumbar and sacral NRS trials resulted in adequate paresthesia coverage and effective pain relief in all 5 patients. Further clinical trials to evaluate long-term success rates and safety are indicated. Detailed mapping studies are needed to evaluate the relationship between electrode placement and paresthesia patterns as well as the optimal stimulation parameters.     

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.     

Cervicothoracic extradural arachnoid cyst: possible association with obstetric brachial plexus palsy

The association of cervicothoracic extradural arachnoid cysts and obstetric brachial plexus palsy has not previously been reported. We report two patients with this association. The first patient is a 9-month-old boy with left obstetric brachial plexus palsy that developed bilateral leg weakness at 6 months of age owing to compression of the spinal cord by a C6 to T8 left cervicothoracic extradural arachnoid cyst. The second patient is a 3-year-old girl with bilateral brachial plexus palsy and spastic paraparesis who had magnetic resonance imaging at 3 days of age that showed intraspinal cord injury and a cervicothoracic extradural arachnoid cyst compressing the spinal cord. We believe that the association of cervicothoracic epidural arachnoid cysts and obstetric brachial plexus palsy in these patients was causal and recommend that the possibility of a cervicothoracic epidural arachnoid cyst be considered in patients with brachial plexus palsy and evidence of spinal cord injury.     

Dorsal Column Stimulation in Persistent Vegetative State

Objectives. The problem of treating patients in a vegetative state remains grossly unresolved, and spinal cord stimulation (SCS) had seemed promising in some studies, suggesting, to us, further study. Materials and Methods. A prospective uncontrolled and nonrandomized observational study for 20 consecutive years (1986–2005) was performed on the effect of SCS in 214 patients in persistent vegetative state (PVS) that resulted from global anoxia and/or, stroke and/or head injury. After confirming the condition of PVS, a spinal cord stimulator, at the C2–C4 level, was implanted, stimulating according to a protocol of 15‐min on/15‐min off during daytime only. The results were evaluated using an efficacy scale designed by us for our study, detecting signs of awareness of self and surrounding. Results. Excellent and positive results were obtained in 109 of 201 patients (54%), but better in those patients below the age of 35, those of PVS of traumatic origin and those patients with regional cerebral blood flow over 20 mL/100 g/min. Conclusions. These findings, though inconclusive of actual benefit of SCS for PVS, indicate to us that further evidence‐based, randomized controlled trials are needed to confirm efficacy of the treatment and define those who are going to benefit from this treatment method.     

The Effect of Spinal Cord Stimulation (SCS) on Static Balance and Gait

Objectives: To investigate whether spinal cord stimulation (SCS) has a negative effect on static balance and gait, which is implicated by the increased incidence of falls leading to frequently occurring lead migrations. Materials and Methods: A controlled trial is performed with 11 subjects (four female, seven male) with a mean age of 46 years old. A baseline measurement consisting of static balance and gait tests was performed. Within two weeks after implantation of a spinal cord stimulator, subjects performed the same tests with both stimulation switched on and off. Static balance was assessed with eyes open and eyes closed on hard surface and foam surface. The velocity of the center of pressure and weight symmetry were the main outcome parameters. Kinematics and spatiotemporal outcome parameters were used to analyze gait. ANOVAs were used to compare between baseline, stimulation on, and stimulation off. Results: Spinal cord stimulation resulted in significant pain relief as scored on a Visual Analog Scale (p < 0.001). Gait width decreased and this change (indicative of improvement in balance) was significant (p = 0.007). No other significant group differences were found between stimulation baseline and post‐surgery measurements. SCS did not influence static balance or gait when group effects were analyzed. Four subjects showed significant differences in static balance between stimulation on and off. Conclusions: The lack of group differences in normal gait and static balance cannot explain the increased incidence of falls. However, four subjects showed an effect of SCS on static balance. Further research to clarify why only a part of the subjects experienced balance problems is recommended and assessments of more demanding balance and gait tasks are desirable.