First detection and characterization of hepatitis E virus (Rocahepevirus ratti) from urban Norway rats (Rattus norvegicus) in the Republic of Korea.

Hepatitis E virus (HEV), an emerging zoonotic pathogen, poses a significant public health concern worldwide. Recently, rat HEV (Rocahepevirus ratti genotype C1; HEV-C1) has been reported to cause zoonotic infections and hepatitis in humans. Human infections with HEV-C1 are considered to be underestimated worldwide due to limited knowledge of transmission routes, genome epidemiology, and the risk assessment of zoonosis associated with these viruses. A total of 186 wild Norway rats (Rattus norvegicus) were collected from the Republic of Korea (ROK) between 2011 and 2021. The prevalence of HEV-C1 RNA was 8 of 180 (4.4%) by reverse-transcription polymerase chain reaction. We first reported three nearly whole-genome sequences of HEV-C1 newly acquired from urban rats in the ROK. Phylogenetic analysis demonstrated that Korea-indigenous HEV-C1 formed an independent genetic group with those derived from R. norvegicus rats in other countries, indicating geographical and genetic diversity. Our findings provide critical insights into the molecular prevalence, genome epidemiology, and zoonotic potential of Rocahepevirus. This report raises awareness of the presence of Rocahepevirus-related hepatitis E among physicians in the ROK.

High-resolution phylogeographical surveillance of Hantaan orthohantavirus using rapid amplicon-based Flongle sequencing, Republic of Korea.

Orthohantaviruses, etiological agents of hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome, pose a critical public health threat worldwide. Hantaan orthohantavirus (HTNV) outbreaks are particularly endemic in Gyeonggi Province in northern area of the Republic of Korea (ROK). Small mammals were collected from three regions in the Gyeonggi Province during 2017 and 2018. Serological and molecular prevalence of HTNV was 25/201 (12.4%) and 10/25 (40%), respectively. A novel nanopore-based diagnostic assay using a cost-efficient Flongle chip was developed to rapidly and sensitively detect HTNV infection in rodent specimens within 3 h. A rapid phylogeographical surveillance of HTNV at high-resolution phylogeny was established using the amplicon-based Flongle sequencing. In total, seven whole-genome sequences of HTNV were newly obtained from wild rodents collected in Paju-si (Gaekhyeon-ri) and Yeoncheon-gun (Hyeonga-ri and Wangnim-ri), Gyeonggi Province. Phylogenetic analyses revealed well-supported evolutionary divergence and genetic diversity, enhancing the resolution of the phylogeographic map of orthohantaviruses in the ROK. Incongruences in phylogenetic patterns were identified among HTNV tripartite genomes, suggesting differential evolution for each segment. These findings provide crucial insights into on-site diagnostics, genome-based surveillance, and the evolutionary dynamics of orthohantaviruses to mitigate hantaviral outbreaks in HFRS-endemic areas in the ROK.

Clinical Impairments and Rotator Cuff Tendon Pathology in Primary and Intrinsic Secondary Adhesive Capsulitis.

OBJECTIVE: This study was conducted to compare the differences in clinical impairments between patients with primary and intrinsic secondary adhesive capsulitis and confirm rotator cuff tendon pathology in intrinsic secondary adhesive capsulitis. DESIGN: This study included 130 patients with unilateral adhesive capsulitis in freezing or frozen stages. Clinical impairment was evaluated using visual analog scale score, shoulder passive range of motion, Cyriax stage, and Constant-Murley score. Plain radiography, ultrasonography, single-contrast arthrography, and intravenous gadolinium-enhanced magnetic resonance imaging were performed in all patients. RESULTS: Among 130 patients, 77 patients were diagnosed as primary adhesive capsulitis and 53 patients as intrinsic secondary adhesive capsulitis. Among intrinsic secondary adhesive capsulitis patients, 44 rotator cuff tendon tears, 6 calcific tendinitis, and 3 rotator cuff tendon tears with calcific tendinitis were observed. No significant intergroup difference was observed in all clinical parameters, including shoulder passive range of motion, visual analog scale, Cyriax stage, and Constant-Murley score. The prevalence of subacromial subdeltoid bursitis was significantly higher in intrinsic secondary adhesive capsulitis compared with primary adhesive capsulitis. CONCLUSIONS: There was no significant difference in all clinical parameters investigated between patients with primary and intrinsic secondary adhesive capsulitis caused by rotator cuff tendon pathology.

A Development of Rapid Whole-Genome Sequencing of Seoul orthohantavirus Using a Portable One-Step Amplicon-Based High Accuracy Nanopore System.

Whole-genome sequencing provides a robust platform for investigating the epidemiology and transmission of emerging viruses. Oxford Nanopore Technologies allows for real-time viral sequencing on a local laptop system for point-of-care testing. Seoul orthohantavirus (Seoul virus, SEOV), harbored by Rattus norvegicus and R. rattus, causes mild hemorrhagic fever with renal syndrome and poses an important threat to public health worldwide. We evaluated the deployable MinION system to obtain high-fidelity entire-length sequences of SEOV for the genome identification of accurate infectious sources and their genetic diversity. One-step amplicon-based nanopore sequencing was performed from SEOV 80-39 specimens with different viral copy numbers and SEOV-positive wild rats. The KU-ONT-SEOV-consensus module was developed to analyze SEOV genomic sequences generated from the nanopore system. Using amplicon-based nanopore sequencing and the KU-ONT-consensus pipeline, we demonstrated novel molecular diagnostics for acquiring full-length SEOV genome sequences, with sufficient read depth in less than 6 h. The consensus sequence accuracy of the SEOV small, medium, and large genomes showed 99.75-100% (for SEOV 80-39 isolate) and 99.62-99.89% (for SEOV-positive rats) identities. This study provides useful insights into on-site diagnostics based on nanopore technology and the genome epidemiology of orthohantaviruses for a quicker response to hantaviral outbreaks.

Therapeutic effect of microcurrent therapy in a rat model of secondary lymphedema.

BACKGROUND: Secondary lymphedema is a clinically incurable disease that commonly occurs following surgical cancer treatment and/or radiation. Microcurrent therapy (MT) has been shown to decrease inflammation and promote wound healing. This study aimed to investigate the therapeutic effect of MT in a rat model for forelimb lymphedema induced by axillary lymph node dissection. METHODS: The model was created by dissecting the right axillary lymph node. Two weeks after surgery, 12 Sprague-Dawley rats were randomly divided into two groups: one that underwent MT in the lymphedematous forelimb (MT, n=6) and a sham MT group (sham MT, n=6). MT was applied daily for 1 h in each session for two weeks. The circumferences of the wrist and 2.5 cm above the wrist were measured 3 days and 14 days after surgery, weekly during MT and 14 days after the last MT. Immunohistochemical staining of pan-endothelial marker (CD31), Masson's trichrome, and western blot analysis of vascular endothelial growth factor C (VEGF-C) and vascular endothelial growth factor receptor-3 (VEGFR3) were performed 14 days after the last MT. Quantification of the area covered by blood vessels (CD31+) and fibrotic tissue area were measured using an image analysis program (ImageJ software). RESULTS: The circumference of the carpal joint in the MT group was significantly decreased 14 days after the last MT compared to that in the sham MT group (P=0.021). The area covered by blood vessels (CD31+) was significantly higher in the MT group than in the sham MT and contralateral control group (P<0.05). The extent of fibrotic tissue was significantly attenuated in the MT group compared to the sham MT group (P<0.05). The expression of VEFGR3 was 2.02-fold higher for MT group, compared for the contralateral control group, which was statistically significant (P=0.035). VEGF-C expression was 2.27-fold higher for MT group than that for contralateral control group; however, the difference between the groups was not significant (P=0.051). CONCLUSIONS: Our findings indicate that MT promotes angiogenesis, and improves fibrosis in secondary lymphedema. Therefore, MT may be a novel and non-invasive treatment modality for secondary lymphedema.

Effectiveness of Mobiderm® bandages in the treatment of cancer-related secondary lymphedema: A pilot study.

Secondary lymphedema is a clinically incurable disease that commonly occurs following surgical cancer treatment and/or radiation. One of the most common forms of lymphedema treatment is complete decongestive therapy (CDT). This study aimed to investigate the clinical effects of new compression bandages (Mobiderm® bandages) in patients with secondary lymphedema after cancer treatment. This study included 17 patients with ipsilateral limb lymphedema after cancer treatment (one male and 16 female patients; age, 45-80 years). Patients were divided into the Mobiderm® bandage group (n = 9) and classical bandage group (n = 8). The International Society of Lymphology (ISL) stage was also evaluated. Limb circumference was measured at 5 to 6 sites per limb to identify the maximal circumference difference (MCD) between the affected and unaffected limbs. Pre-and posttreatment MCD were analyzed. After intensive CDT, both the Mobiderm® bandage group (1.2 ± 0.56 cm) and classical bandage group (0.85 ± 0.40 cm) had a significant decrease in MCD compared to pretreatment (P < .05). However, in patients with ISL stage 2, the mean MCD decrease rate was greater in the Mobiderm® bandage group (22.82 ± 10.92 %) than in the classical bandage group (12.18 ± 8.1 1%)(P = .045). Both new bandages (Mobiderm® bandages and classical bandages) reduced the circumference of limb edema in patients with secondary lymphedema after cancer treatment. This study findings suggest that Mobiderm® bandages as an alternative modality for controlling ISL stage 2 lymphedema.

Two methods of extracorporeal shock-wave therapy in a rat model of secondary lymphedema: a pilot study.

OBJECTIVES: To compare the effectiveness of two methods of extracorporeal shock-wave therapy (ESWT) in a rat model of forelimb lymphedema, induced by axillary lymph node dissection. METHODS: Sprague-Dawley rats were randomly allocated to a group that received 500 ESWT shocks only in the lymphedematous forelimb (Forelimb/ESWT) and a group that received 300 ESWT shocks in the axilla and 200 shocks in the lymphedematous forelimb (Axilla+Forelimb/ESWT). The circumferences of each limb were then measured. Immunohistochemistry for a pan-endothelial marker (cluster of differentiation [CD]31) and lymphatic vessel endothelial hyaluronan receptor-1, and western blot analysis for vascular endothelial growth factor receptor-3 (VEGFR3) and VEGF-C were performed. RESULTS: The circumferences of the limbs showed significant effects of group and time following surgery. The circumferences at the carpal joint and 2.5 cm above were smallest in the naïve limbs, larger in the Axilla+Forelimb/ESWT group, and the largest in the control group. VEGFR3 tended to be expressed at a higher level in the Axilla+Forelimb/ESWT group (1.96-fold) than in the Forelimb/ESWT group (1.20-fold) versus the opposite non-edematous forelimbs, although this difference was not statistically significant. CONCLUSIONS: These data suggest that ESWT protocols have differential effects on angiogenesis and lymphangiogenesis in lymphedematous limbs.

Multifocal acquired demyelinating sensory and motor neuropathy misdiagnosed as carpal tunnel syndrome: a case report.

Multifocal acquired demyelinating sensory and motor neuropathy (MADSAM), a subtype of chronic inflammatory demyelinating polyneuropathy, is a non-compressive peripheral nerve disorder. Symptoms of MADSAM include asymmetrical weakness and sensory deficits in the distribution of individual peripheral nerves, which are frequently noted in the distal portion of peripheral nerves. MADSAM can be easily misdiagnosed as any of the various compressive peripheral neuropathies. Here, we present a case of MADSAM misdiagnosed as carpal tunnel syndrome (CTS). A 53-year-old woman had bilateral asymmetrical hand weakness (left hand: significant weakness, right hand: slight motor weakness) and a slight weakness of her bilateral lower extremities. Sensory deficit was found on the volar side of her left hand. She had visited many clinics previously and was diagnosed with CTS. However, an electrodiagnostic study performed in our hospital did not identify CTS but indicated a demyelinating peripheral neuropathy in all limbs. On the basis of the patient's clinical symptoms and laboratory findings, she was diagnosed with MADSAM. When patients exhibit progressive aggravating motor weakness and sensory deficits in more than one distal limb without a specific finding of compressive neuropathy in electrodiagnostic studies, clinicians should consider the possibility of MADSAM.

Obturator nerve injury diagnosed by nerve conduction: a case report.

The obturator nerve lies deep within the pelvis, and it can be damaged by direct injury during surgery. In this study, nerve conduction was used to confirm an obturator nerve injury in a patient who presented with hip adductor weakness following gynecological surgery for endometrial cancer. A 56-year-old woman complained of weakness in the right adductor muscles after a laparoscopic hysterectomy due to endometrial cancer. Seven days after surgery, the degree of weakness of the right hip adductor was Medical Research Council (MRC) Scale 1; thus, a nerve conduction velocity test was conducted. To obtain the compound muscle action potentials of the obturator nerve, stimulation was performed (1.5 cm inferior and 1.5 cm lateral to the pubic tubercle) with a surface electrical simulator and recording (midpoint of the right medial thigh) of the adductor muscles. The compound muscle action potentials of the right obturator nerve showed lower amplitude (left side: 2.7 mV vs. right side: 0.3 mV) and delayed onset latency (left side: 3.2 ms vs. right side: 2.2 ms). These results indicate a partial right obturator neuropathy. Therefore, nerve conduction could be useful to diagnose an early-stage obturator nerve injury and provide information on the degree of damage.

Airway invasion in non-neurologically ill patients with dysphagia: Contributing factors and associated problems during swallowing process. A retrospective observational study.

Dysphagia can occur among patients receiving medical care despite having no history of neurologic disease. The current study aimed to investigate factors contributing to airway invasion among non-neurologically ill patients with dysphagia.This retrospective study included 52 non-neurologically ill patients who complained of swallowing difficulty and consulted the Department of Rehabilitation Medicine for videofluoroscopic swallowing studies between January 2018 and June 2019. Patients were then divided into 2 groups according to the presence of airway invasion (penetration or aspiration) based on videofluoroscopic swallowing study findings, with group 1 (n = 26) consisting of patients with airway invasion and group 2 (n = 26) consisting of those without airway invasion. Demographic information, functional ambulation ability within the past 3 months, presence of community acquired pneumonia (CAP), nutritional status, degree of dehydration, history of intensive care unit stay, history of endotracheal intubation, and videofluoroscopic dysphagia scale were reviewed.Patients with airway invasion exhibited decreased functional ambulation ability, greater incidence of CAP, and lower serum albumin concentration than patients without airway invasion (P < .05). Airway invasion among non-neurologically ill patients was significantly associated with functional ambulation ability [odds ratio (OR), 3.57; 95% confidence interval (CI), 1.14-11.19; P = .03], serum albumin concentration under 3.5 g/dL (OR, 4.90; 95% CI, 1.39-17.32; P = .01), and presence of CAP (OR, 5.06; 95% CI, 1.56-16.44; P = .01). Groups 1 and 2 had a videofluoroscopic dysphagia scale score of 37.18 and 16.17, respectively (P < .05). Moreover, bolus formation, tongue-to-palate contact, premature bolus loss, vallecular residue, coating of pharyngeal wall, and aspiration score differed significantly between both groups (P < .05).Airway invasion among non-neurologically ill patients was related to decreased functional ambulation ability, lower serum albumin concentration, and presence of CAP. The results presented herein can help guide clinical management aimed at preventing airway invasion among non-neurologically ill patients.

Effects of intra-articular pulsed radiofrequency current administration on a rabbit model of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial proliferation and inflammation. Intra-articular corticosteroid injections are commonly used for the treatment of arthritis affecting one or two joints. Although corticosteroid injections are fast-acting, repeated usage can result in severe adverse events. Recently, intra-articular pulsed radiofrequency (PRF) stimulation has been proposed to treat arthritis. The aim of the present study was to compare the effectiveness of intra-articular PRF with corticosteroid injection based on histopathological and motion analysis of an ovalbumin (OVA)-induced RA rabbit model. RA was induced in the right knee joint of 18 rabbits via OVA injection. The rabbits were randomly allocated into a PRF, an intra-articular corticosteroid injection or a sham PRF stimulation group. Movement was assessed in the rabbits before treatment, then at 2, 4 and 8 weeks after treatment using walking distance, fast walking time and mean walking speed. Histopathological evaluation of the distal femur and synovium was conducted 2, 4 and 8 weeks after treatment. Motion analysis demonstrated that changes in all movement variables showed significant group and time interaction as well as group effect among the three groups. The semiquantitative score based on the histopathological findings for the distal femoral condyle decreased 2 and 4 weeks after both the PRF and steroid groups, compared with the sham PRF group. Moreover, in the synovium, the semiquantitative histological score in the PRF and steroid groups tended to be lower compared with the sham PRF group, although this result was not statistically significant. Thus, intra-articular PRF stimulation may delay cartilage destruction and improve functional motion in RA.

The Successful Treatment of Herniated Lumbar Discs That are Refractory to Repeated Epidural Steroid Injection by Using a Navigable Percutaneous Disc Decompression Device: A Case Series.

PURPOSE: In most cases, lumbosacral radicular pain caused by herniated lumbar discs (HLDs) can be controlled with epidural steroid injections (ESIs). However, when the HLDs are large, the pain may not respond to ESIs. A navigable, percutaneous, disc decompression device has recently been developed to manage radicular pain that is secondary to HLD, which allows the wand tip to approach the herniated disc by rotating a control wheel. We performed a percutaneous disc decompression using the navigable percutaneous disc decompression device in two patients with a large HLD that did not respond to repeated ESIs. PATIENTS AND METHODS: Patients A and B are presented with scores of 7 and 8 on the numeric rating scale (NRS), respectively. Both had lumbosacral radicular pain due to right central HLDs at L4-5 and L5-S1, despite repeated ESIs. Percutaneous disc decompression was performed under C-arm fluoroscopy. The wand was inserted through the introducer needle. Using the control wheel, we placed the needle tip on the posterolateral portion of the herniated disc. The radiofrequency current was applied to the herniated portion of the disc. The procedural time was 20-30 minutes. RESULTS: Neither of the patients reported adverse post-procedural effects. At their 1-week follow-up, patient A and B's NRS pain scores had reduced to 2 and 1, respectively. At their 2-year follow-up, patient A had mild pain (NRS 1), and patient B reported no pain. CONCLUSION: The navigable percutaneous disc decompression device may be effective for pain alleviation in patients with lumbosacral radicular pain that is refractory to repeated ESIs.

Effect of Custom-Made Foot Orthosis for Scoliosis with Pelvic Malalignment in a Patient with Myelomeningocele of Partial Neurological Deficit: A Case Report.

BACKGROUND The treatment of patients with spinal deformities, such as developmental scoliosis in children with myelomeningocele, poses a formidable challenge. We observed the effects of a custom-made foot orthosis in a case of mild scoliosis with pelvic malalignment, in a patient with myelomeningocele. CASE REPORT The patient was a 5-year-old female who was diagnosed with myelomeningocele and who had a partial neurological deficit. At the time of the first visit, the patient showed moderate pelvic rotation to the clockwise side during gait and severe left anterior pelvic tilting during the drooping upper body. Radiographic images revealed mild lumbar scoliosis and severe pelvic asymmetry. After applying a custom-made foot orthosis for 8 months, the patient showed moderate improvement of pelvic rotation and tilting. Clinical biomechanical changes were well correlated with radiographic images. CONCLUSIONS These results highlight that custom-made foot orthosis controlling 3 motion planes of the pelvis had a corrective effect on mild lumbar scoliosis in a patient with myelomeningocele.

Usefulness of ultrasound assessment of median nerve mobility in carpal tunnel syndrome.

BACKGROUND: Carpal tunnel syndrome (CTS) is the most common peripheral compression neuropathy of the upper extremity. Recently, dynamic ultrasound (US) imaging has shown differences in median nerve mobility between the affected and unaffected sides in CTS. PURPOSE: The present study was performed to compare the median nerve mobility between patients with CTS and healthy individuals, and to correlate median nerve mobility with the severity of CTS. MATERIAL AND METHODS: A total of 101 patients (128 wrists) with CTS and 43 healthy individuals (70 wrists) were evaluated. Electrodiagnostic studies were initially conducted to determine the neurophysiological grading scale (NGS). The cross-sectional area (CSA) of the median nerve and the grade of median nerve mobility were measured using US. RESULTS: The mean grade of median nerve mobility in the CTS group (1.9) was significantly lower than that in the control group (2.6; P < 0.001). There were significant negative correlations between the grade of median nerve mobility and distal motor latency of the median nerve (r = -0.218, P = 0.015), NGS (r = -0.207, P = 0.020) and CSA of the median nerve (r = -0.196, P = 0.028). CONCLUSION: The grade of median nerve mobility was negatively correlated with the severity of CTS. US assessment of median nerve mobility may be useful in diagnosing and determining the severity of CTS.

Transcutaneous neuromuscular electrical stimulation applied to optimal points on the lower abdomen and lumbar paraspinal region changes gait parameters in patients with lumbar degenerative kyphosis.

BACKGROUND: Lumbar degenerative kyphosis (LDK) is characterized by sagittal imbalance resulting from degenerative loss of lumbar lordosis. The ability of transcutaneous neuromuscular electrical stimulation (NMES) to activate deep lumbar stabilizing muscles has been demonstrated. OBJECTIVE: The aim of this study was to evaluate the effects of transcutaneous NMES applied to optimal points on the lower abdomen and lumbar paraspinal region on gait problems in patients with lumbar degenerative kyphosis (LDK). METHODS: Twenty-one patients with lumbar degenerative kyphosis underwent three walking sessions in the following order; walking for 5 minutes without NMES, walking with NMES on the lumbar multifidus (LM) only, and walking with NMES on both LM and transverse abdominis (TrA)/obliquus internus (OI). Differences in gait parameters at the commencement and completion of each of the three sessions were evaluated by gait analysis. RESULTS: During the 5-minute walk with NMES applied to the LM or to the LM and TrA/OI, participants showed lesser increases in spine forward tilt, pelvic anterior tilt, and external foot progression angle, and a lesser decrease in hip internal rotation than when walking without NMES (P< 0.05). In addition, with NMES, patients showed less decrement in gait velocity and stride length at walk completion than patients walking without NMES (P< 0.05). However, in the comparison between walks with NMES applied to the LM and walks with NMES applied to the LM and TrA/OI, we could not find any significant difference in changes of gait parameters (p> 0.05). CONCLUSIONS: Transcutaneous NMES applied at optimal points on the lower abdomen and back could provide a means of treating gait problems caused by a stooped trunk in LDK patients.

Distribution of Platelet-rich Plasma after Ultrasound-Guided Injection for Chronic Elbow Tendinopathies.

Characteristics of the spreads of platelet-rich plasma (PRP) are not widely known despite commonly use. This study aims to evaluate whether PRP stays within the injected area by using ultrasonography, to improve understanding of the spreads of intratendinous injected PRP. Thirty-nine patients (15 males, 24 females; mean age, 49.3 years), who had symptoms on their elbows (> 6 months) and diagnosed as lateral (25 elbows) or medial (14 elbows) tendinopathies of elbow, were included. The severity of tendon pathology was assessed by ultrasonography as tear or no tear. Immediately after ultrasound-guided PRP injection, ultrasound images were evaluated to assess the area of PRP distribution, which was defined as the presence of fluid or microbubbles. Ultrasound revealed that 13 elbows had tendon tear and 26 had no tear, respectively. Post-injection ultrasound confirmed the injected PRP was within the tendon in all cases. The mean distance of distribution from the injection site was 12.6 mm (5.0-26.0 mm). There was no difference in the distance of PRP distribution between tendon tear and no tear. Injected PRP spread to soft tissue outside the tendon in 20 of 39 cases. Intra-articular extension of PRP was observed in 5 cases. Although PRP remained intratendinous after the injection in all cases, some portion tended to spread outside from the injection site in a short space of time. Postinjection ultrasonographic imaging has a value for observing the spreading patterns of intratendinous PRP injection.

Changes in Neuroglial Activity in Multiple Spinal Segments after Caudal Epidural Pulsed Radiofrequency in a Rat Model of Lumbar Disc Herniation.

BACKGROUND: Herniated lumbar discs can induce sciatica by mechanical compression and/or chemical irritation. It was recently reported that neuroglial cellular activity after pulsed radiofrequency (PRF) application to a single dorsal root ganglion (DRG) attenuated neuroglial activity at the corresponding spinal dorsal horn. Recently, caudal epidural PRF has been used to manage neuropathic pain, but evidence of molecular changes after the administration of caudal epidural PRF to attenuate neuropathic pain is lacking, and it has not been determined whether caudal epidural PRF affects neuroglial activity at different spinal levels. OBJECTIVES: Using immunohistochemical methods in a rat model of lumbar disc herniation, the authors investigated the effects of caudal epidural PRF administration on pain-related behavior, on the activations of microglia and astrocytes in spinal cord, and on the expressions of calcitonin gene-related peptide (CGRP) and Transient receptor potential vanilloid 1(TRPV1) in the DRG at the L3, L4, L5, L6, and S1 levels. STUDY DESIGN: Controlled animal trial. SETTING: University hospital laboratory. METHODS: Forty-five Sprague-Dawley rats were randomly assigned to a sham-operated group (n = 10) or a nucleus pulposus (NP)-exposed group (n = 35). Rats in the NP-exposed group were further subdivided into a NP-exposed with sham stimulation group (the NP-nonPRF group; n = 13) or a NP exposed with caudal epidural PRF stimulation group (the NP-PRF group; n = 22). Pulsed radiofrequency was administered on postoperative day 10 (POD 10) by placing an electrode in the caudal epidural space through the sacral hiatus and administering 5 Hz of PRF current for 600 seconds (maximum tip temperature 42°C). Rats were tested for mechanical allodynia on POD 10 and on days 7 and 14 after caudal epidural PRF administration (post-PRF). At 14 days post-PRF, sections of the spinal cord from L3, L4, L5, L6, and S1 were immunostained for ionized calcium-binding adapter molecule 1 (Iba1) and glial fibrillary acidic protein (GFAP), and DRGs from the same levels were immunostained for CGRP and TRPV1. RESULTS: Mechanical withdrawal thresholds increased at 7 days post-PRF (P = 0.04), and the immunohistochemical expression of Iba1 in the L5 spinal dorsal horn and of CGRP in the L5 DRG were quantitatively reduced (P < 0.001) at 14 days post-PRF. Furthermore, the upregulations of Iba1 at L3, L4, L6, and S1 dorsal horns and CGRP at L6 DRG were also attenuated by caudal epidural PRF (P < 0.001). LIMITATION: We examined molecular changes only in ipsilateral lumbar regions and at 14 days post-PRF. CONCLUSION: Caudal epidural PRF reduced mechanical allodynia and downregulated microglia activity and CGRP expression at the lumbar disc herniated level and in adjacent lumbar spinal levels in a rat model of lumbar disc herniation.Key words: Caudal, pulsed radiofrequency, multisegmental, lumbar disc herniation, microglia, calcitonin gene-related peptide.

Comparison of the Effects of Ultrasound-Guided Interfascial Pulsed Radiofrequency and Ultrasound-Guided Interfascial Injection on Myofascial Pain Syndrome of the Gastrocnemius.

OBJECTIVE: To investigate the comparative treatment effects of ultrasound-guided pulsed radiofrequency treatment (UG-PRF) in the gastrocnemius interfascial space and ultrasound-guided interfascial injection (UG-INJ) on myofascial pain syndrome. METHODS: Forty consecutive patients with myofascial pain syndrome of the gastrocnemius were enrolled and were allocated to one of the two groups. Twenty patients were treated by UG-PRF delivered to the gastrocnemius interfascial space (UG-PRF group) and the other 20 patients were treated by interfascial injection (UG-INJ group). The primary outcome measure was the numeric rating score (NRS) for pain on pressing the tender point in the gastrocnemius, and the secondary outcome measure was health-related quality of life as determined by the Short Form-36 questionnaire (SF-36). NRSs were obtained at the first visit, immediately after treatment, and at 2 and 4 weeks post-treatment, and physical component summary scores (PCS) and mental component summary scores (MCS) of the SF-36 questionnaire were measured at the first visit and at 4 weeks post-treatment. RESULTS: Immediately after treatments, mean NRS in the UG-PRF group was significantly higher than that in the UG-INJ group (p<0.0001). However, at 2 and 4 weeks post-treatment, the mean NRS was significantly lower in the UG-PRF group (both p<0.0001). Similarly, at 4 weeks post-treatment, mean PCS and MCS were significantly higher in the UG-PRF group (p<0.0001 and p=0.002, respectively). CONCLUSION: Based on these results, the authors conclude that ultrasound-guided gastrocnemius interfascial PRF provides an attractive treatment for myofascial pain syndrome of the gastrocnemius.