bluuebunny/crossref_metadata_2025 huggingface dataset:
Deep Gluteal Pain Secondary to Pelvic Wall Endometriosis- A Case Report
Authors: Rabie Mohamed
Published: October 2024

BACKGROUND: Chronic pelvic pain is a common condition that affects up to 26% of patients according to a recent systematic review. The clinical history and presentation are widely variable. Diagnosis is difficult and often delayed. CASE REPORT: A 44-year-old woman presented to the pain clinic with a 5-year history of unexplained deep left buttock pain. The pain symptoms initially suggested entrapment of the left pudendal nerve. A subsequent magnetic resonance imaging showed an abnormal mass in the left ischiorectal fossa. Further biopsy confirmed endometriosis of the lateral pelvic wall, a rarely reported finding. Her pain symptoms considerably improved 70% after initiating medical therapy. CONCLUSIONS: The diagnosis of chronic pelvic pain can be difficult and often delayed. The presence of unexplained pain symptoms, with a cyclical pattern in a child-bearing age, should raise the suspicion toward endometriosis. KEY WORDS: Gluteal pain, chronic pelvic pain, endometriosis, central sensitization, pelvic, pudendal, case report
Treatment of Synovial Cyst Stenosis With Radiofrequency Lesioning of the Posterior Facet Capsule – A Case Report of Two Patients
Authors: Haufe Scott
Published: October 2024

BACKGROUND: Zygapophyseal joint synovial cyst spinal stenosis can cause radicular pain issues that often require repetitive cystic rupture procedures or decompressive surgery for resolution. CASE REPORT: We present 2 cases of lumbar spinal stenosis with radicular findings due to lumbar zygapophyseal synovial cyst impingement that were not improved with physical therapy, epidural steroid injections, synovial cyst injections, or transforaminal injections. Synovial cysts were 1 cm and 0.7 cm preprocedure, respectively, for these 2 patients. Both cases were treated with radiofrequency (RF) lesioning of the posterior facet capsule at 3 locations from medial to lateral along the facet joint line posteriorly at the affected spinal level with complete resolution of the radicular symptoms in both cases. Follow-up was 6 months and 10 years for the 2 patients. CONCLUSIONS: RF lesioning of the synovial capsule may be an effective treatment for synovial cyst stenosis in lieu of conventional surgery or repetitive cyst rupture techniques. KEY WORDS: Synovial cyst, stenosis, radiofrequency, zygapophyseal joint
Topical Capsaicin as a Preventative Treatment for Chemotherapy-Induced Peripheral Neuropathy (CIPN): A Case Series
Authors: Kolcun Georgina
Published: October 2024

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a well-known adverse effect of chemotherapy treatment. Despite its prevalence, prevention and treatment of CIPN remain challenging. CASE REPORT: In this case series, we present the use of topical 0.075% capsaicin as a preventative measure for CIPN in patients with newly-diagnosed stage II breast cancer undergoing chemotherapy. Patients were instructed to use capsaicin cream 3 times daily on hands and feet throughout the course of chemotherapy and for an additional month after chemotherapy concluded. CONCLUSIONS: None of the 5 patients had any symptoms suggestive of CIPN after being followed for 12 months. These findings support further investigation of low-dose capsaicin as a prophylactic measure to prevent CIPN. KEY WORDS: Chemotherapeutic-induced peripheral neuropathy, topical capsaicin, preventative, neuropathy, cancer pain
A Series of Stellate Ganglion Blocks for the Management of Post-Traumatic Stress Disorder: A Case Report
Authors: Downing Michael
Published: October 2024

BACKGROUND: An overactive sympathetic nervous system plays a role in the pathophysiology of post-traumatic stress disorder. The cluster of sympathetic nerves located in the inferior cervical column, known as the stellate ganglion, is an optimal target for anesthetic delivery in an effort to calm this sympathetic overdrive. Recent studies have shown that stellate ganglion blocks may be beneficial for patients with post-traumatic stress disorder (PTSD). CASE REPORT: The authors present a 40-year-old man who is a military veteran with an existing diagnosis of PTSD. He experiences frequent symptoms such as flashbacks, anxiety attacks, and insomnia that have not improved with standard treatment modalities including antidepressants, anxiolytics, group therapy, and psychotherapy. The patient experienced symptomatic relief immediately after the stellate ganglion block and continued relief after the third block. CONCLUSION: Stellate ganglion blocks are an effective alternative therapy for PTSD. KEY WORDS: Stellate ganglion block, post-traumatic stress disorder (PTSD), case study
Abducens Nerve Palsy - A Rare Complication of Spinal Cord Stimulator Insertion: Case Report and Literature Review
Authors: Chow Vanessa Jane
Published: October 2024

BACKGROUND: Spinal cord stimulation (SCS) is an emerging therapeutic intervention for intractable chronic pain. However, SCS surgery is not exempt from complications such as lead migration, infections, hardware malfunction and neurological deficits. CASE REPORT: We present this case report on bilateral abducens nerve palsy, as a rare iatrogenic complication of SCS system insertion in a 65-year-old man with intractable chronic pain. After failing conservative treatment and explant, he underwent corrective strabismus surgery and achieved symptom control. CONCLUSION: The case presents a diagnostic and management challenge due to the nature of his presentation, neuroimaging pitfalls and limited high-quality evidence for management. We recognise cranial nerve palsy as a potential, yet real, complication of SCS surgery, of which abducens nerve palsy presents significant detriment to patients lives. As SCS continues to expand in clinical practice, inevitably, so will its iatrogenic sequela signalling the need for greater recognition and formation high-quality evidence for efficacious management. KEY WORDS: Spinal cord stimulation insertion, abducens nerve palsy, chronic pain, case report
Resolution of Celiac Artery Compression Syndrome Following Spinal Cord Stimulation: A Case Report
Authors: Newton Felecia
Published: October 2024

BACKGROUND: Celiac artery compression syndrome is characterized by postprandial epigastric pain, weight loss, and occasional epigastric bruit, and can be difficult to treat because there are no definitive guidelines. We present a case of a 47-year-old man who had postprandial pain, weight loss, and chronic diarrhea for 5 years, which was resolved with spinal cord stimulation (SCS). CASE REPORT: After extensive workup, a diagnosis of celiac artery compression syndrome was confirmed. Due to previous treatment failures, repeat celiac plexus blocks becoming less efficacious, and surgical unsuitability, the patient underwent an SCS trial. They continued having pain relief, so a permanent spinal cord stimulator lead was implanted. CONCLUSION: We highlight complete resolution of celiac artery compression syndrome using SCS. KEY WORDS: Case report, celiac artery compression syndrome, celiac plexus block, median arcuate ligament syndrome, spinal cord stimulation
The Utilization of Stellate Ganglion Block in the Treatment of Long-COVID: A Case Series
Authors: Alnatour Omar
Published: October 2024

BACKGROUND: With the recent COVID-19 pandemic, chronic pain physicians undoubtedly face the challenge of treating long-COVID within the already complex chronic pain patient population. Sympathetic blockade of the stellate ganglion has historically been utilized as a diagnostic and therapeutic tool in confirming and targeting the sympathetically mediated component of many chronic pain conditions, but its role in treating long-COVID symptoms has yet to be thoroughly studied or elucidated. CASE SERIES: We present a unique case series where the utilization of stellate ganglion blockade in one case and use of stellate ganglion blockade followed by rhizotomy in another were successful in sustained and near-complete relief of all initial long-COVID symptoms during a 3-month follow-up period. CONCLUSIONS: Our case series presents promising results on the role of stellate ganglion blockade in the sustained and near-complete relief of multiple long-COVID symptoms during the longest known follow-up period to date. KEY WORDS: COVID-19, dysautonomia, long-COVID, rhizotomy, stellate ganglion block
Peripheral Nerve Stimulation for Arm Pain in an Adolescent Girl with Ewing Sarcoma as Bridge Therapy to Chemotherapy: A Case Report
Authors: Brown Ashlyn
Published: October 2024

BACKGROUND: Cancer commonly presents discomfort from abnormal cell growth in healthy tissue and is often inadequately managed. Peripheral nerve stimulation (PNS), mainly for non-cancer chronic pain, has emerged as a minimally invasive option for neuropathic cancer-related pain when conventional methods fail. Limited research, primarily in adults, has focused on PNS in the non-oncological population. CASE REPORT: A 14-year-old adolescent girl with a history of obesity, diabetes, and Ewing sarcoma in her left proximal humerus experienced severe pain, initially rated at 10/10. After undergoing ultrasound-guided left suprascapular PNS as a 60-day bridge therapy to chemotherapy, her pain improved to 3/10 at lead removal and remained at 4/10 at 3 months postremoval. CONCLUSION: PNS is a promising and less invasive neuromodulation approach for managing tumor-related bone pain. Our case study illustrates the effectiveness of PNS placement for significant pain reduction, although limitations, such as delayed response and the need for further randomized-controlled studies, are acknowledged. KEY WORDS: Neuromodulation, peripheral nerve stimulation, Ewing sarcoma, arm pain, bone pain, chemotherapy, teen, adolescent
Ischiofemoral Impingement, An Atypical Cause of Gluteal Pain: A Case Report
Authors: Ritter Stephen
Published: October 2024

BACKGROUND: This is a case of unilateral gluteal pain in a 54-year-old woman. CASE REPORT: The patient presented with a 4-month history of left buttock pain after a traumatic fall. Her pain was exacerbated primarily while sitting. Pelvic x-rays showed bilateral acetabular dysplasia. Magnetic resonance imaging of the left femur without contrast was significant for ischiofemoral impingement (IFI), including compression of the quadratus femoris (QF). The QF space displayed a minimum dimension of 0.7 cm. The patient was scheduled for an ultrasound-guided QF injection, but cancelled the procedure due to symptomatic improvement with supportive care. CONCLUSIONS: IFI has become increasingly recognized as an uncommon cause of posterior hip, gluteal, or groin pain. Diagnosis of IFI can be challenging given the broad differential and potential for multiple etiologies of pain. Acetabular dysplasia leads to increased femoral anteversion. Thus, patients with acetabular dysplasia may be vulnerable to the development of IFI. KEY WORDS: Ischiofemoral impingement, acetabular dysplasia, ischiofemoral impingement, buttock pain, gluteal pain, case report
Trigeminal Neuralgia and Associated Hydrocephalus: Not a Mere Incidental Finding? A Case Report and Literature Review
Authors: Roth Jonathan
Published: October 2024

BACKGROUND: Trigeminal neuralgia (TN) is most commonly related to vascular compression of the trigeminal root entry zone into the brainstem. Secondary causes of compression are much less common. TN as a sole manifestation of hydrocephalus has rarely been reported in the literature. CASE REPORT: We describe a young woman with medically resistant TN, who was discovered to have a tectal plate glioma causing secondary obstructive hydrocephalus. In addition, she had an incidental finding of ecchordosis physaliphora. Cerebrospinal fluid diversion by an endoscopic third ventriculostomy resulted in TN resolution. CONCLUSION: Hydrocephalus is a rare diagnosis to consider as a secondary cause for TN. Since the literature on this is sparse, it can be only suggested that in very select cases, treating the hydrocephalus may also treat the TN. Additional studies and reports are required. KEY WORDS: Trigeminal neuralgia, hydrocephalus, ecchordosis physaliphora, tectal plate glioma
Sacroplasty for Zone III Sacral Insufficiency Fracture: A Case Report Utilizing a Midline Approach and Articulating Osteotome
Authors: Govindan Susheel
Published: October 2024

BACKGROUND: Sacral insufficiency fractures can be a debilitating cause of low back pain in the elderly population. While sacroplasty is recommended for the treatment of persistent pain from sacral insufficiency fractures, the anatomical location of Zone III fractures can put patients at a higher risk of neurological complications during repair. CASE REPORT: We present a case of a 71-year-old woman with a Denis Zone III sacral insufficiency fracture who underwent percutaneous sacroplasty. The procedure was performed by utilizing an articulating osteotome in the long-axis approach along the curvature of the sacrum. The use of an articulating osteotome allowed for small trajectory adjustments, thereby lowering the procedural risks of cement extravasation and erroneous cannulation. CONCLUSIONS: The patient reported significant pain relief and no immediate complications following the procedure. Fluoroscopically guided percutaneous sacroplasty using an articulating osteotome is a safe and effective method for treating sacral insufficiency fractures. KEY WORDS: Sacrum, bone fracture, sacroplasty, back pain, case report
The Combined Use of Acute Regional and Interventional Pain Offers Superior Quality of Life in Palliative Care
Authors: Music Stephen
Published: October 2024

BACKGROUND: Pain is a common symptom associated with cancer and can greatly compromise quality of life, motivation, and further treatments. Intrathecal pump (ITP) offers improved pain scores and clinical outcomes, while reducing the adverse effects of systemic analgesics. CASE REPORT: A 29-year-old woman with neurofibromatosis type 1 had a malignant peripheral nerve sheath tumor in her right thigh surgically resected. However, one month later, metastatic lesions were found throughout her body. Despite chemotherapy, the disease spread and pain became severe resulting in multiple hospitalizations and halting treatment. Multimodal analgesia was pursued, including regional anesthesia, but she was unable to tolerate the adverse effects of systemic opioids. For long-term analgesia, ITP was pursued, which significantly improved her pain control and quality of life. CONCLUSIONS: In advanced stages of cancer, we highlight the significant benefits ITP offers with improved quality of life and reduced medication side-effect profiles vs systemic analgesics. KEY WORDS: Intrathecal pump, regional anesthesia, palliative care, cancer, chronic pain, opioids
An Anterior Femoral Nerve Glomus Tumor Causing Twenty Years of Neuropathic Pain: A Case Report
Authors: Williams Eric
Published: October 2024

BACKGROUND: Glomus tumors are a rare, yet painful, neoplasm commonly occurring in the subungual area of the digits. While uncommon, a glomus tumor can present in extradigital locations, leading to delays in diagnosis. CASE REPORT: We present a case of a 53-year-old man with a 20-year history of right thigh pain. Previous diagnostic workup and treatment with spinal cord stimulation and peripheral nerve stimulation did not yield resolution. Exam with ultrasound revealed a hypoechoic lesion. Upon targeted surgical exploration, a mass near the right anterior femoral cutaneous nerve was identified and resected. Pathology was consistent with a glomus tumor. Since the operation, the patient has experienced complete relief after a 1.2-year follow-up. CONCLUSION: Glomus tumors are treated surgically. Ultrasound may be useful in well-localized, neuropathic pain of the extremity, highlighting the importance of clinicians becoming familiar with employing this modality. While rare, a glomus tumor should be included in the differential diagnosis. KEY WORDS: Glomus tumor, chronic neuropathic pain, case report
Prior Hypermobile Spinal Cord Stimulator Removal With Difficult Reimplantation due to Epidural Scarring Provides Relief in Postlaminectomy Syndrome
Authors: Robinson Christopher
Published: October 2024

BACKGROUND: When spinal cord stimulation (SCS) therapy fails for postlaminectomy syndrome (PLS), oftentimes the device is not removed or explanted, or rarely, it is reimplanted with the hopes of success with a new implant. CASE REPORT: Our patient is a 52-year-old man with a history of PLS treated with L5-S1 discectomy who presented with refractory chronic low back pain. He underwent an initial SCS implant with significant pain relief, but was limited due to unwanted abdominal stimulations with movement and explanted 8 months later. Despite his prior experience, a second SCS was implanted but with great difficulty due to widespread epidural scarring leading to a positional headache, which self-resolved. Fortunately, the second implant provided > 50% pain relief. CONCLUSIONS: Our case highlights the importance of reconsidering an SCS reimplantation which may benefit a select group of individuals, though more research is required to define this subset of patients. KEY WORDS: Hypermobile, unwanted stimulations, explant, reimplantation, spinal cord stimulator
Radiofrequency Ablation of the Thoracic Descending Branch of the Posterior Rami: An Effective Intervention for Facet Joint Pain. A Case Report
Authors: Tang Kevin
Published: October 2024

BACKGROUND: Thoracic spine pain is believed to have a comparable prevalence to that of neck pain and low back pain in the general population. Recent discoveries in thoracic spine neuroanatomy have shown that the descending branch of the posterior ramus innervates the thoracic facet joint capsule. We present a case in which thermal radiofrequency ablation of the descending branch was used to significantly relieve pain in a patient with thoracic facet joint pain. CASE REPORT: A 57-year-old woman presented with a 4-month history of severe midthoracic back pain. The patient had failed initial conservative treatment including oral pain medications and physical therapy for 3 months. She ultimately elected for 2 bilateral diagnostic blocks of the T4-T6 descending branches and subsequent radiofrequency ablation; this treatment resulted in complete pain relief and functional improvement. CONCLUSIONS: Thoracic spine descending branch thermal radiofrequency ablation may be a treatment option for thoracic facet joint pain. KEY WORDS: Back pain, thoracic facet joint, descending branch, radiofrequency ablation, posterior ramus, thoracic spine, back, pain
Effect of Dexmedetomidine, Dexamethasone, and Ondansetron on Postoperative Nausea and Vomiting in Children Undergoing Dental Rehabilitation: A Randomized Controlled Trial
Authors: Shama Ahmed Abdelaziz , Elsayed Elsayed , Albraithen Abdulrahman , Arafa Sherif Kamal
Published: October 2024

BACKGROUND: Postoperative nausea and vomiting (PONV) are common unpleasant adverse effects after surgery. The incidence of PONV in pediatric patients is often twice as high as in adults. OBJECTIVES: This study aimed to evaluate the effects of dexmedetomidine, dexamethasone, and ondansetron for preventing PONV in children undergoing dental rehabilitation surgery. STUDY DESIGN: A prospective, randomized controlled clinical trial. SETTING: Sharurah Armed Forces Hospital, Ministry of Defense Medical Services, Saudi Arabia. METHODS: One hundred patients (6-12 years old) scheduled for dental rehabilitation were included. Patients were randomly allocated into 4 groups (25 each) to receive either 0.15 mg/kg dexamethasone (DEX), 0.05 mg/kg ondansetron (OND), 0.3 microgram/kg dexmedetomidine (DEXMED), or normal saline (control[CONT]) in DEX, OND, DEXMED or CONT groups, respectively, via infusion after induction of anesthesia. The primary outcome was a PONV incident in the first 24 hours. Secondary outcomes were: granisetron doses during 24 hours postoperative, Paediatric Anaesthesia Emergence Delirium (PAED) scale, Pediatric Objective Pain Scale (POPS) for 4 hours postoperatively, and complications in the first 24 hours. RESULTS: The reduction of PONV and the overall number of patients who developed PONV was statistically significant in the DEXMED group compared to the CONT group (P = 0.041). However, the DEXMED group was higher compared to the DEX and OND groups but not statistically significant. Granisetron requirements and doses were statistically significantly lower in the DEXMED group than in the CONT group. PAED and POPS scores were much better in the DEXMED group than in the other groups with a statistically significant difference in most of the time measurements. LIMITATION: Optimal dexmedetomidine dose for better effect on PONV without affecting hemodynamic stability requires more studies. CONCLUSION: Dexmedetomidine is effective in reducing PONV in children undergoing dental rehabilitation with better sedative and analgesic scores as compared to the control group. KEY WORDS: Dexmedetomidine, dexamethasone, dental rehabilitation, ondansetron, postoperative nausea and vomiting
Timing of Percutaneous Balloon Kyphoplasty for Osteoporotic Vertebral Compression Fractures
Authors: Jia Zhiwei
Published: October 2024

BACKGROUND: Percutaneous balloon kyphoplasty (PKP) is widely used to treat osteoporotic vertebral compression fractures (OVCFs). In addition to rapid and effective pain relief, the ability to recover the lost height of fractured vertebral bodies and reduce the risk for complications are believed to be the main advantages of this procedure. However, there is no consensus on the appropriate surgical timing for PKP. OBJECTIVES: This study systematically evaluated the relationship between the surgical timing of PKP and clinical outcomes to provide more evidence for clinicians to choose the intervention timing. STUDY DESIGN: Systematic review and meta-analysis. METHODS: The PubMed, Embase, Cochrane Library, and Web of Science databases were systematically searched for relevant randomized controlled trials and prospective, and retrospective cohort trials published up to November 13, 2022. All included studies explored the influence of PKP intervention timing for OVCFs. Data regarding clinical and radiographic outcomes and complications were extracted and analyzed. RESULTS: Thirteen studies involving 930 patients with symptomatic OVCFs were included. Most patients with symptomatic OVCFs achieved rapid and effective pain relief after PKP. In comparison to delayed PKP intervention, early PKP intervention was associated with similar or better outcomes in terms of pain relief, improvement of function, restoration of vertebral height, and correction of kyphosis deformity. The meta-analysis results showed there was no significant difference in cement leakage rate between early PKP and late PKP (odds ratio [OR] = 1.60, 95% CI, 0.97–2.64, P = 0.07), whereas delayed PKP had a higher risk for adjacent vertebral fractures (AVFs) than early PKP (OR = 0.31, 95% CI: 0.13–0.76, P = 0.01). LIMITATIONS: The number of included studies was small, and the overall quality of the evidence was very low. CONCLUSIONS: PKP is an effective treatment for symptomatic OVCFs. Early PKP may achieve similar or better clinical and radiographic outcomes for treating OVCFs than delayed PKP. Furthermore, early PKP intervention had a lower incidence of AVFs and a similar rate of cement leakage compared with delayed PKP. Based on current evidence, early PKP intervention might be more beneficial to patients. KEY WORDS: Percutaneous balloon kyphoplasty, osteoporotic vertebral compression fractures, osteoporosis, surgery, operative timing
Comparison of Craniocaudal Spread of Lumbar Erector Spinae Plane Block With Two Volumes of Local Anesthetics
Authors: Hong JiHee
Published: October 2024

BACKGROUND: The erector spinae plane block (ESPB) is a less invasive, safer, and technically easier procedure compared to the conventional neuraxial technique. Although the ESPB is a favored and easy technique compared to neuraxial block, there is no study with a large number of patients describing the exact spread level of injected local anesthetics. OBJECTIVES: The purpose of this study was to identify ESPB spread in the craniocaudal direction and the incidence of spread into the epidural space, psoas muscle, and intravascular system. STUDY DESIGN: Prospective design. SETTING: A tertiary university hospital, pain clinic. METHODS: Right- or left-sided ESPBs (170 at L4) with fluoroscopy subsequent to ultrasound guidance due to acute or subacute low back pain were included. In this study, 10 mL (ESPB 10 mL group, contrast medium 5 mL) or 20 mL (ESPB 20 mL group, contrast medium 7 mL) of a local anesthetic mixture was injected. After confirming a successful interfascial plane spreading under ultrasound guidance, the remaining local anesthetic was injected under fluoroscopic guidance. The spread level of ESPB in the craniocaudal direction and the occurrence of injectate into the epidural space or psoas muscle was assessed using the saved fluoroscopic images. These images were compared between the ESPB 10 mL and ESPB 20 mL groups. Also, the presence or absence of intravascular injection during ESPB was assessed and compared between the ESPB 10 mL and ESPB 20 mL groups. RESULTS: The ESPB 20 mL group had a more extensive caudal distribution of contrast medium than the ESPB 10 mL group. Also, the total number of lumbar vertebral segments was significantly higher in the ESPB 20 mL group than that of the ESPB 10 mL group (1.7 ± 0.4 vs 2.1 ± 0.4, P < 0.001). Among all injections performed in this study, epidural, psoas muscle, and intravascular injections occurred in 2.9%, 5.9%, and 12.9%, respectively. LIMITATIONS: Only the craniocaudal direction was evaluated without evaluating the spread pattern in the medial to lateral direction. CONCLUSION: The ESPB 20 mL group showed a more extensive distribution of contrast medium than that of the ESPB 10 mL group. Inadvertent injections into the epidural space, psoas muscle, and intravascular system were observed. Among them, intravascular system injections were found to be the most common (12.9%). KEY WORDS: Erector spinae plane block, spread level, psoas muscle, intravascular injection
Fluoroscopic Analysis of Cannula Tip Location During Radiofrequency Thermocoagulation of the Trigeminal Ganglion
Authors: Hong JiHee
Published: October 2024

BACKGROUND: Trigeminal neuralgia (TN) is the most common excruciating cranial neuralgia in the elderly population. Radiofrequency thermocoagulation (RFT) of the trigeminal ganglion is an alternative treatment for medically intractable patients with TN. RFT cannula tip position is an important issue since it is related to treatment outcome and patient safety. OBJECTIVES: The purpose of this study was to evaluate the fluoroscopic position of a cannula tip when a maximal stimulation-induced paresthesia was obtained and the treatment outcome using a Barrow Neurological Institute (BNI) pain scale. STUDY DESIGN: Retrospective analysis. SETTING: An interventional pain management practice in South Korea. METHODS: The final cannula tip position obtained under maximal electrical stimulation of the face was analyzed using previously saved fluoroscopic images. RESULTS: The cannula tip was located exactly in the clival line in 10 patients (29.4%) with maxillary division (V2) TN. There were 24 patients of V2 TN (70.5% ) in whom the cannula tip was located below the clival line. Over 50% of cannula tips were located at -11 mm to -15 mm below the clival line in mandibular division (V3) TN. Forty-four patients (83%) who received RFT in the trigeminal ganglion demonstrated BNI I or II. LIMITATIONS: The number of patients with V3 TN was smaller than that of V2 TN. Only short-term efficacy was evaluated, but not long-term efficacy or recurrence rate of facial pain. CONCLUSIONS: Nearly 70% of patients in V2 TN and all patients in V3 TN, the cannula tip was positioned below the clival line. RFT of the trigeminal ganglion showed a successful treatment outcome with BNI I or II in 83% of patients. KEY WORDS: Cannula tip, clival line, fluoroscopic position, pain scale, stimulation-induced paresthesia, radiofrequency
Adipose Tissue Impacts Radiofrequency Ablation Lesion Size: Results of an Ex Vivo Poultry Model
Authors: Wahezi Sayed
Published: October 2024

BACKGROUND: Radiofrequency ablation (RFA) is a common treatment in which radiofrequency (RF) is used to heat neural tissue and reduce pain. The impact of adipose content in tissue on the lesion size may impact efficacy, and to date, there is little, if any, data comparing its influence on RFA. OBJECTIVES: We evaluated the influence of adipose tissue on RF lesion size. STUDY DESIGN: Controlled, ex vivo study. SETTING: Academic institution in a procedural setting. METHODS: RF lesions were created using 20-G 10-mm protruding electrode (PE) needles inserted into unbrined chicken breasts and thighs at 21°C. RF current was applied for 90 seconds at 80°C. Chicken breasts were used as the control group and chicken thighs were used as the high adipose variant. Four different groups were examined: 1- Standard 20 g RFA needle, 2- 20 g RFA PE needle, 3- Standard RFA needle with lidocaine 2% injectate, and 4- Standard RFA needle with iohexol 240 mg injectate. There were 12 lesions performed in each group; length, width, and depth were measured. RESULTS: The control group had significantly deeper lesions in all 4 cohorts. Lesions’ lengths were smaller in the fat-rich group. The control and PE cohorts showed a significant difference in width between the 2 fat-rich and nonfatty groups. LIMITATIONS: Radiofrequency ablation was performed at room temperature and not heated to physiological temperature. This was an ex vivo study, thus factors of human anatomy and physiology could not be evaluated. CONCLUSIONS: Adipose tissue content was inversely related to lesion size in all samples. This factor should be considered when assessing methods of enhancing lesion size in human models. KEY WORDS: Radiofrequency, ablation, lesion size, injection, adipose tissue, tissue modeling, interventional pain, education
Results From a Prospective, Clinical Study (US-nPower) Evaluating a Miniature Spinal Cord Stimulator for the Management of Chronic, Intractable Pain
Authors: Kottalgi Shilpa
Published: October 2024

BACKGROUND: Chronic, intractable, neuropathic pain is readily treatable with spinal cord stimulation (SCS). Technological advancements, including device miniaturization, are advancing the field of neuromodulation. OBJECTIVES: We report here the results of an SCS clinical trial to treat chronic, low back and leg pain, with a micro-implantable pulse generator (micro-IPG). STUDY DESIGN: This was a single-arm, prospective, multicenter, postmarket, observational study. SETTING: Patients were recruited from 15 US-based comprehensive pain centers. METHODS: This open-label clinical trial was designed to evaluate the performance of the Nalu™ Neurostimulation System (Nalu Medical, Inc., Carlsbad, CA) in the treatment of low back and leg pain. Patients, who provided informed consent and were successfully screened for study entry, were implanted with temporary trial leads. Patients went on to receive a permanent implant of the leads and micro-IPG if they demonstrated a >= 50% reduction in pain during the temporary trial period. Patient-reported outcomes (PROs), such as pain scores, functional disability, mood, patient impression of change, comfort, therapy use profile, and device ease of use, were captured. RESULTS: At baseline, the average pain Visual Analog Scale (VAS) score was 72.1 ± 17.9 in the leg and 78.0 ± 15.4 in the low back. At 90 days following permanent implant (end of study), pain scores improved by 76% (VAS 18.5 ± 18.8) in the leg and 75% (VAS 19.7 ± 20.8) in the low back. Eighty-six percent of both leg pain and low back pain patients demonstrated a >= 50% reduction in pain at 90 days following implant. The comfort of the external wearable (Therapy Disc and Adhesive Clip) was rated 1.16 ± 1.53, on average, at 90 days on an 11-point rating scale (0 = very comfortable, 10 = very uncomfortable). All PROs demonstrated statistically significant symptomatic improvement at 90 days following implant of the micro-IPG. LIMITATIONS: Limitations of this study include the lack of long-term results (beyond 90 days) and a relatively small sample size of 35 patients who were part of the analysis; additionally, there was no control arm or randomization as this was a single-arm study, without a comparator, designed to document the efficacy and safety of the device. Therefore, no direct comparisons to other SCS systems were possible. CONCLUSIONS: This clinical study demonstrated profound leg and low back pain relief in terms of overall pain reduction, as well as the proportion of therapy responders. The study patients reported the wearable aspects of the system to be very comfortable. KEY WORDS: Spinal cord stimulation, chronic pain, radiculopathy, micro-IPG, battery-free, persistent spinal pain syndrome, failed back surgery syndrome, low back pain, leg pain
Differences in Pain Assessments Between Inpatients and Nurses Leads to Considerable Misestimated Pain
Authors: Hung Chih-Jen
Published: October 2024

BACKGROUND: Pain assessments are an important aspect of health care quality because the high prevalence of pain in inpatients may contribute to complications. Several studies revealed a gap in the pain intensity evaluated by nurses (PEN) and patients (PEP). The aim of the present study was to analyze the correlation and agreement between pain assessments conducted by nurses and patients, and to determine patients at high risk of misestimated pain. OBJECTIVES: To compare the difference of pain intensity between the questionnaires conducted by additional assessors and electronic records by nursing staff. STUDY DESIGN: A retrospective study. SETTING: A medical center in Taichung, Taiwan. METHODS: We approached 1,034 patients admitted from January 1, 2018 to December 31, 2018 in our hospital. We compared the assessments of pain intensity using questionnaires conducted by additional assessors with those entered into electronic records by nursing staff. Continuous data were reported as the mean (± standard deviation). The analysis of agreement and correlation were performed by kappa statistics or weighted kappa statistics, and correlation (Spearman rank correlation method). RESULTS: Among the 1,034 patients, 307 patients were excluded. Thus, the final analysis included 686 patients. Patients’ median pain intensity was 5 in PEP and 1 in PEN. The patients’ pain intensity was underestimated (PEN < PEP) in 539 patients (78.6%), matched (PEN = PEP) in 126 patients (18.3%), and overestimated (PEN > PEP) in 21 patients (3.1%). The surgical interventions (chi squared = 7.996, and P = 0.018) and pain in the past 24 hours (chi squared = 17.776, and P < 0.001) led to a significant difference. LIMITATIONS: The limitation of the study was the single-center and retrospective design. CONCLUSIONS: The gap in pain assessments between inpatients and nurses is an important issue in daily practice. The underestimations of pain were more common than overestimations (78.6% vs 3.1%). Surgical interventions and persistent pain lasting over 24 hours were high risk factors for underestimation, but patients’ gender, receiving anesthesia, type of anesthesia, and patient-controlled analgesia did not contribute significantly to differences in pain estimation. KEY WORDS: Pain, assessment, correlation, agreement
ED90 of Sufentanil in Epidural Initiation for Labor Analgesia in Latent Phase and Active Phase During the First Labor Stage
Authors: Xu Tao
Published: October 2024

BACKGROUND: The standard solutions for epidural labor analgesia include both local anesthetics and opioids. The concept of the standard epidural use of local anesthetics in labor analgesia has shifted from high concentrations to high volumes with low concentrations. However, the optimal dosage of opioids needed to initiate and maintain epidural labor analgesia in different phases during the first labor stage has rarely been studied. OBJECTIVE: The present study aimed to determine the optimal sufentanil dose for epidural initiation in the latent and active phases during the first stage of labor. STUDY DESIGN: A prospective, double-blind, sequential dose-finding study. SETTING: A Class A tertiary obstetrics and gynecology hospital. METHODS: The study included 80 nulliparae with cervical dilatation of 2-4 cm and 5-6 cm, with 40 nulliparae in each group. A research dose of sufentanil combined with ropivacaine 13 mg in epidural initiation with a volume of 15 mL was administered to the puerperant. A 1-microgram sufentanil dose and a 2.5-micrograms sufentanil dose were used for the first puerperant of each group. The dose of sufentanil for the subsequent puerperant was determined by the response of the previous puerperant according to the biased coin up-and-down design in each trial. The primary outcome was a visual analog scale score of <= 3 at 15, 30, and 45 minutes after epidural administration, including the given dose of sufentanil. According to the response of each puerperant, the 90% effective doses and their 95% confidence intervals were estimated by isotonic regression and bootstrapping according to the response of each puerperant. RESULTS: The 90% effective doses of sufentanil for puerperants were 1.91 micrograms (95% confidence intervals 1.82-2.35 micrograms) and 4.90 micrograms (95% confidence intervals 4.82-5.35 micrograms) in epidural initiation in the latent and active phases, respectively. The 90% effective doses were 62.5% (95% confidence intervals 50.8-64.0%) lower in the latent phase than that in the active phase during the first stage of labor. LIMITATIONS: Both spontaneous labor and induced labor were included in this study, and the degree of pain in these 2 types of labor is different. Further, only nulliparae were recruited in the study. CONCLUSIONS: Different sufentanil doses should be adopted in epidural initiation in different phases during the first stage of labor due to the large differences in the demand for sufentanil. KEY WORDS: Sufentanil, 90% effective dose, epidural initiation, labor analgesia, active phase, latent phase, first labor stage
Effects of Ketamine on Chronic Postsurgical Pain in Patients Undergoing Surgery: A Systematic Review and Meta-analysis
Authors: Han Ruquan
Published: October 2024

BACKGROUND: Chronic postsurgical pain (CPSP) has become a common complication during the perioperative period. The efficacy of one of the most potent strategies, ketamine, remains unclear. OBJECTIVES: The aim of this meta-analysis was to evaluate the effect of ketamine on CPSP in patients undergoing common surgeries.. STUDY DESIGN: Systematic review and meta-analysis. METHODS: English-language randomized controlled trials (RCTs) published in MEDLINE, Cochrane Library, and EMBASE from 1990 through 2022 were screened. RCTs with a placebo control group that evaluated the effect of intravenous ketamine on CPSP in patients undergoing common surgeries were included. The primary outcome was the proportion of patients who experienced CPSP 3 – 6 months postsurgery. The secondary outcomes included adverse events, emotional evaluation, and 48 hour postoperative opioid consumption. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Pooled effect sizes were measured using the common-effects model or random-effects model, and several subgroup analyses were conducted. RESULTS: Twenty RCTs were included with 1,561 patients. Our pooled meta-analysis showed a significant difference between ketamine and placebo in the treatment of CPSP (Relative Risk [RR] = 0.86; 95% CI, 0.77 – 0.95; P = 0.02; I2 = 44%). In the subgroup analyses, our results indicated that compared with placebo, intravenous ketamine might decrease the prevalence of CPSP 3 – 6 months postsurgery (RR = 0.82; 95% CI, 0.72 – 0.94; P = 0.03; I2 = 45%). For adverse events, we observed that intravenous ketamine might lead to hallucinations (RR = 1.61; 95% CI, 1.09 – 2.39; P = 0.27; I2 = 20%) but did not increase the incidence of postoperative nausea and vomiting (RR = 0.98; 95% CI, 0.86 – 1.12; P = 0.66; I2 = 0%). LIMITATIONS: Inconsistent assessment tools and follow-up for chronic pain may contribute to the high heterogeneity and limitation of this analysis. CONCLUSIONS: We discovered that intravenous ketamine may reduce the incidence of CPSP in patients undergoing surgery, especially 3 – 6 months postsurgery. Because of the small sample size and high heterogeneity of the included studies, the effect of ketamine in the treatment of CPSP still needs to be explored in future large-sample, standardized-assessment studies. KEY WORDS: Ketamine, chronic postsurgical pain, perioperative period, meta-analysis, randomized controlled trial
Effectiveness of Intermediate Cervical Plexus Block in Whiplash-Associated Disorder: A Prospective Observational Trial in Fifty Patients
Authors: Niraj G
Published: October 2024

BACKGROUND: Whiplash trauma can result in a range of symptoms, including chronic neck pain, headache, facial pain, upper back pain, and tinnitus, which comprises whiplash-associated disorder (WAD). Intermediate cervical plexus block (iCPB) is a novel intervention that targets the upper cervical nerves and anecdotal reports suggest benefits in WAD. OBJECTIVES: We hypothesized that the cervical plexus may have a role in the pathogenesis of WAD and blocking the cervical plexus may provide analgesia. STUDY DESIGN: Prospective observational trial. SETTING: Tertiary pain medicine unit at a university teaching hospital. METHODS: Adult patients who presented with refractory chronic neck pain following whiplash were included in a prospective observational trial. The pragmatic trial studied the effectiveness of 2 sequential cervical plexus blocks (iCPB with local anesthetic [iCPB-LA] and iCPB with steroid and LA mixture [iCPB-Steroid]) in refractory chronic neck pain following whiplash. Patients who reported < 50% relief at 12 weeks after iCPB-LA were offered iCPB-Steroid. Primary outcome was “neck pain at its worst in the last 24 hours” at 12 weeks. Secondary outcomes included change in neck disability index, employment status, and mood. RESULTS: After excluding cervical zygapophyseal joint dysfunction, 50 patients underwent the iCPB-LA between June 2020 and August 2022. Five patients reported > 50% relief (durable relief) at 12 weeks and 3 patients were lost to follow-up. Forty-two patients received iCPB-Steroid. iCPB-Steroid was associated with significant reduction in neck pain, neck disability, and improvement in mood at 12 weeks when compared to the block with LA. In addition, iCPB-Steroid was associated with significant reduction in neck pain and disability at 24 weeks. Due to functional improvement, 34 patients (34/50, 78%) were able to maintain employment. LIMITATIONS: This is an open-label, observational, single-center study in a limited cohort under a single physician. Cervical facet joint dysfunction was ruled out clinically and radiologically. CONCLUSIONS: Cervical plexus may play a central role in the pathogenesis of WAD. iCPB could potentially be a treatment option in this cohort. KEY WORDS: Intermediate cervical plexus block, whiplash, trigemino-cervical complex, whiplash-associated disorder, neck pain, chronic headache
The Effect of Genetic Variation on the Sensitivity to Opioid Analgesics in Patients With Postoperative Pain: An Updated Meta-analysis
Authors: Ren Zhen-Yu
Published: October 2024

BACKGROUND: Responsiveness to opioid analgesics differs among patients with acute postoperative pain. OBJECTIVE: Our study presents the most recent evidence on the effect of genetic variations on postoperative pain, opioid consumption, nausea, and vomiting in patients treated with opioids. STUDY DESIGN: An updated systematic review and meta-analysis on the association between single-nucleotide polymorphisms and opioids administered to patients with acute postoperative pain. METHODS: PubMed, Embase, ISI Web of Science, and the Cochrane Library databases were searched for articles published from February 1, 2014, through December 31, 2021. RESULTS: Added to the previous meta-analysis, 39 studies (a total of 7,455 patients) were included in the final meta-analysis. Highlights of the findings include: 1) human mu-opioid receptor gene 118G allele carriers required more opioids during the first postoperative 24 hours (standard mean difference [SMD] = -0.27; 95% CI,-0.40 to -0.14; P < 0.0001) and 48 hours (SMD = -0.52; 95% CI, -0.83 to -0.20; P = 0.001), and reported higher pain scores during the first 24 hours but not at the 48-hour postoperative period (SMD = -0.09, 95% CI, -0.15 to -0.03; P = 0.002) compared to homozygous 118AA patients. 2) patients with the CYP3A4 *1G allele required fewer opioids during the first 24-hour postoperative period (SMD = 0.59; 95% CI, 0.05 to 1.14; P = 0.03) compared to patients with the homozygous CYP3A4*1/*1 allele. 3) Adenosine triphosphate-binding cassette subfamily B member-1 (ABCB1) 3435T allele carriers required more opioids during the 48-hour postoperative period (SMD = -0.21; 95% CI, -0.38 to -0.04; P = 0.02) compared to homozygous CC carriers. 4) Catechol-O-methyl transferase 158A allele carriers required fewer opioids during the first 24-hour postoperative period (SMD = 0.33; 95% CI, 0.15 to 0.51; P = 0.0004) compared to homozygous GG carriers. No significant differences were observed in patients with CYP2D6*10 and ABCB1 G2677A/T genetic polymorphisms. LIMITATIONS: Several loci were not analyzed in detail due to insufficient clinical data. Furthermore, nongenetic factors that affected analgesic efficacy and the clinical outcome of postoperative pain were not discussed and were not the aim of this meta-analysis. CONCLUSIONS: In combination with previous systematic reviews and meta-analyses, our results indicate that the A118G allele variant of OPRM1 and the *1*1G allele variant of CYP3A4 have a profound influence on individual differences in opioid reactivity in patients with postoperative pain. Our results, together with the identification of additional single nucleotide polymorphisms in future studies, may provide a theoretical basis for precise clinical analgesia. KEY WORDS: Single nucleotide polymorphism, postoperative pain, opioid, meta-analysis