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Chaudhary R, Khanna J, Bansal S, Bansal N. Current Insights into Carpal Tunnel Syndrome: Clinical Strategies for Prevention and Treatment. Curr Drug Targets 2024; 25:221-240. [PMID: 38385490 DOI: 10.2174/0113894501280331240213063333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/01/2024] [Accepted: 01/12/2024] [Indexed: 02/23/2024]
Abstract
BACKGROUND Carpal tunnel syndrome (CTS) is a condition that is caused by medial nerve compression, resulting in symptoms such as numbness, tightness, or weakness in the hand. OBJECTIVES The aim of the study was to find out the genetic modulation, mechanism, available treatment, and recommendation for carpal tunnel syndrome at its specific stage. METHODS Almost 200 papers were searched for this review article, and 145 articles were selected. The literature was collected from different sources like Google scholar, PubMed, a directory of open-access journals, and science.gov by using keywords, such as treatment, risk factors, recommendation, and clinical features of carpal tunnel syndrome. RESULTS The most efficient non-surgical treatment is methylprednisolone acetate, which reduces inflammation by acting on the glucocorticoid receptor in conjunction with immunofilling. It has also been used successfully as a second-line drug for the treatment of patients with mild or moderate conditions in order to provide relief. New non-pharmacological options include laser therapy in acupuncture, transcutaneous electric nerve stimulation (TENS), and sham therapy. Modern treatments like TENS, laser therapy, splints, and injections of methylprednisolone acetate have been demonstrated to be helpful in sporadic situations. For patients with mild and moderate problems, more research should be conducted that includes the combination of these surgical and non-surgical treatments. CONCLUSION We propose a multifunctional panel construct and define standard data items for future research into carpal tunnel syndrome. A discussion on idiopathic carpal tunnel syndrome, risk factors, combination of therapies, using guidelines-based recommendations and treatment should be initiated.
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Affiliation(s)
- Rishabh Chaudhary
- Department of Pharmacology, M. M. College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, Haryana-133207, India
| | - Janvi Khanna
- Department of Pharmacology, M. M. College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, Haryana-133207, India
| | - Seema Bansal
- Department of Pharmacology, M. M. College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, Haryana-133207, India
| | - Nitin Bansal
- Department of Pharmacy, Chaudhary Bansilal University, Bhiwani, India
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2
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Seong JW, Kim Y, Kwon DR, Yang CJ, Özçakar L. Effectiveness of Novel Sympathetic Nerve Entrapment Point Injections for Chronic Migraine: A Pilot Study. Life (Basel) 2023; 14:57. [PMID: 38255672 PMCID: PMC10817430 DOI: 10.3390/life14010057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 12/26/2023] [Accepted: 12/27/2023] [Indexed: 01/24/2024] Open
Abstract
No studies to date have investigated the ability of sympathetic nerve entrapment point saline (SNEP) injections to achieve long-term pain relief in patients with migraine. Therefore, this study aimed to investigate the safety and long-term efficacy of repeat splenius capitis (SC) SNEP injections in patients with migraine (with/without tension-type headache). This retrospective, single-arm study included 12 patients with migraine. Isotonic saline was injected into their SC approximately six times for 3 months. Headache frequency, duration (hour/week), intensity (using the visual analog scale), and quality of life (using the Headache Impact Test-6) were assessed during the follow-up visits for up to 24 months after the first injection. Changes before and after treatment were assessed using repeated-measures analysis of variance. Significant reductions in headache frequency, duration, and intensity were observed at all assessment points after SNEP injections when compared with the baseline values (p < 0.05), while the patients' headache-related quality of life also improved. Treatment was continued for up to 3 months to maintain these improvements, and no worsening of status or adverse effects were observed in any of the patients over the following 24 months. Our results show that SNEP injections may offer persistent, substantial, and clinically relevant benefits in patients with migraine.
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Affiliation(s)
- Jeong Won Seong
- Department of Family Medicine, Sarang Tong-sa Research Center, 2nd Floor, 477, Jinnyangho-ro, Jinju-si 52686, Republic of Korea;
| | - Yuntae Kim
- Department of Physical Medicine and Rehabilitation, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, 31 Suncheonhyang 6-gil, Dongnam-gu, Cheonan-si 31151, Republic of Korea;
| | - Dong Rak Kwon
- Department of Rehabilitation Medicine, Muscle Research Center, Catholic University of Daegu School of Medicine, 33 Duryugongwon-ro 17-gil, Nam-Gu, Daegu 42472, Republic of Korea
| | - Cheol-Jung Yang
- Department of Orthopedic Surgery, Bonetouch Orthopaedic Clinic, 262, Godeok-ro, Gangdong-gu, Seoul 05269, Republic of Korea;
| | - Levent Özçakar
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Hacettepe, Tıp Fakültesi, Altındağ/Ankara 06230, Turkey;
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Chien CY, Wang JD, Lin CC. Nerve excitability test and lead toxicity: a case-control study. J Occup Med Toxicol 2023; 18:19. [PMID: 37653420 PMCID: PMC10472560 DOI: 10.1186/s12995-023-00385-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 08/11/2023] [Indexed: 09/02/2023] Open
Abstract
BACKGROUND Although conventional electrophysiological parameters have been proposed as clinical indicators for monitoring lead neuropathies, their correlations with blood lead level are weak. In this study, we investigated the applicability of nerve excitability tests (NETs) to evaluate lead intoxication. METHODS Fourteen workers who were exposed to lead with an elevated blood level ranging from 17.8 to 64.9 µg/dL and 20 healthy controls with similar ages and body heights were enrolled. Both workers and controls underwent nerve conduction studies (NCSs), motor evoked potentials (MEPs) with transcranial magnetic stimulation (TMS), and NETs. RESULTS NCSs showed prolonged distal latencies and decreased motor nerve conduction velocity of median nerves in the workers but without significant correlation to blood lead level (BLL). Significantly prolonged MEP latency was observed in the workers (+ 6 ms). NETs demonstrated hyperpolarized resting membrane potentials in stimulus-response curves and changes in the property of potassium channels under a hyperpolarized current in threshold electrotonus, implying that lead hyperpolarized nerves by interfering with potassium channels. NETs also showed a better correlation with BLL than conventional electrophysiological parameters. CONCLUSIONS Axonal hyperpolarization and central conduction delay are more apparently reflecting elevated BLL than NCS. NET may have the potential for early detection of lead neuropathy.
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Affiliation(s)
- Chung-Yao Chien
- Department of Neurology, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, 138 Sheng Li Road, Tainan, 704, Taiwan
| | - Jung-Der Wang
- Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Occupational and Environmental Medicine, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Chou-Ching Lin
- Department of Neurology, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, 138 Sheng Li Road, Tainan, 704, Taiwan.
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.
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Nah S, Kim K, Choi S, Woo S, Han S. SYMPATHETIC NERVE ENTRAPMENT POINT INJECTION AS AN ADJUVANT TREATMENT FOR INTRACTABLE CLUSTER HEADACHE: A CASE REPORT. J Emerg Med 2023:S0736-4679(23)00230-5. [PMID: 37355419 DOI: 10.1016/j.jemermed.2023.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/10/2023] [Accepted: 04/10/2023] [Indexed: 06/26/2023]
Abstract
BACKGROUND Cluster headache (CH) is characterized by severe unilateral pain ranging from the orbital to the temporal regions with ipsilateral autonomic manifestations. Although most patients respond to drugs or oxygen inhalation, some do not. In this case report, we introduce sympathetic nerve entrapment point injection (SNEPI), a new adjuvant treatment for CH. CASE REPORT We introduce two CH patients who did not respond well to pharmacological treatment or 100% oxygen inhalation, but who improved after SNEPI. Patient 1, a 42-year-old man, visited the Emergency Department (ED) with severe periorbital right frontal headache accompanied by ipsilateral rhinorrhea, conjunctival injection, and eyelid edema. The symptoms did not fully respond to drugs or oxygen inhalation, but improved after SNEPI into the tender point of the splenius capitis (SC) muscle; there was no further pain for 1 month thereafter. Patient 2, a 26-year-old woman, presented to the ED complaining of severe headache in the right supraorbital-temporal-occipital region with ipsilateral lacrimation and conjunctival congestion. The patient was taking various drugs for CH, but there was no improvement; the symptoms improved dramatically after SNEPI into the tender points of the SC and paraspinal deep muscles (levels T1-2), and the pain was well managed with reduced drug doses for 3 months. Why Should an Emergency Physician Be Aware of This? CH can cause severe acute pain, and sometimes pharmacological treatment or oxygen inhalation is not effective. SNEPI, which is inexpensive and can be easily performed, may be considered as an adjuvant treatment for intractable CH in the ED.
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Affiliation(s)
- Sangun Nah
- Department of Emergency Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Republic of Korea
| | - Kangho Kim
- Department of Emergency Medicine, InHa University Hospital, Incheon, Republic of Korea
| | - Sungwoo Choi
- Department of Emergency Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Republic of Korea
| | - Seungho Woo
- Department of Emergency Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Republic of Korea
| | - Sangsoo Han
- Department of Emergency Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Republic of Korea
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5
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Cho Y, Han Y, Kim Y, Han S, Oh K, Chae H, Hongmin C, Ryu M. Anatomical structures and needling method of the back-shu points BL18, BL20, and BL22 related to gastrointestinal organs: A PRISMA-compliant systematic review of acupoints and exploratory mechanism analysis. Medicine (Baltimore) 2022; 101:e29878. [PMID: 36316824 PMCID: PMC9622668 DOI: 10.1097/md.0000000000029878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Acupuncture treatment on back-shu points (BSPs) has received attention owing its ability to control the function of visceral organs. We aimed to conduct a systematic review to provide detailed information on the effectiveness and safety of BL18, BL20, and BL22 on the digestive system in terms of soft tissue and anatomical structure and assist in the appropriate application. METHODS Medline, Cochrane Library, EMBASE, OASIS, RISS, and CNKI were searched from their inception to July 2021. This systematic review included randomized controlled trials, controlled clinical trials, case series, and case reports that addressed anatomical structures or needling methods of BL18, BL20, and BL22. RESULTS In total, 115 articles were included from the 7 electronic databases. One hundred eight articles described the depth and method. A total of 96 articles described depth, 86 articles described the angle, and 74 articles described both. Seventy-nine articles described the target muscles and anatomical structure. Acupuncture on BSP is effective in gastrointestinal diseases because of compression of the spinal nerve, sympathetic nerve hyperactivity, and connection of the diaphragm. By reviewing each study's acupuncture method and target muscles, we analyzed the angle and depth of the needle that effectively leads to therapeutic response. CONCLUSIONS This study provides guidance on applying needles in terms of anatomical structures to yield therapeutic responses. However, few studies have assessed how to effectively stimulate BSP to trigger digestive effects and their mechanisms. Additional studies on the relationship between BSP and the digestive system are needed to use these acupoints for digestive diseases.
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Affiliation(s)
- Yeonwoo Cho
- College of Korean Medicine, Dongguk University, Ilsan City, Republic of Korea
| | - Yaejin Han
- College of Korean Medicine, Dongguk University, Ilsan City, Republic of Korea
| | - Yeji Kim
- College of Korean Medicine, Dongguk University, Ilsan City, Republic of Korea
| | - Sihyun Han
- College of Korean Medicine, Dongguk University, Ilsan City, Republic of Korea
| | - Kichang Oh
- College of Korean Medicine, Dongguk University, Ilsan City, Republic of Korea
| | - Hyocheong Chae
- Academic Affairs Board, Korean Medical Society of Soft Tissue, Seoul, Republic of Korea
| | - Chu Hongmin
- Academic Affairs Board, Korean Medical Society of Soft Tissue, Seoul, Republic of Korea
- Daecheong Island Branch Office of a Ongjin Public Health Center, Incheon, Republic of Korea
- *Correspondence: Chu Hongmin, Daecheong Island Branch Office of a Ongjin Public Health Center, 3, Daecheong-ro, Daecheong-myeon, Ongjin-gun, Incheon, Republic of Korea (e-mail: )
| | - Myungseok Ryu
- Academic Affairs Board, Korean Medical Society of Soft Tissue, Seoul, Republic of Korea
- Daemyung Korean Medicine Clinic, Seoul, Republic of Korea
- *Correspondence: Chu Hongmin, Daecheong Island Branch Office of a Ongjin Public Health Center, 3, Daecheong-ro, Daecheong-myeon, Ongjin-gun, Incheon, Republic of Korea (e-mail: )
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6
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Kwon DR, Kim Y. Sternocleidomastoid size and upper trapezius muscle thickness in congenital torticollis patients: A retrospective observational study. Medicine (Baltimore) 2021; 100:e28466. [PMID: 34967390 PMCID: PMC8718228 DOI: 10.1097/md.0000000000028466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 12/10/2021] [Indexed: 01/05/2023] Open
Abstract
The purpose of this study was to investigate the upper trapezius muscle thickness (UTMT) in congenital muscular torticollis (CMT) patients and determine the correlation among sternocleidomastoid muscle thickness (SCMT), accessory nerve (AN) cross-sectional area (CSA), and UTMT in CMT.This retrospective study consisted of 2 participant groups: Group 1 (SCM mass CMT, n = 20) and Group 2 (Postural CMT, n = 22). For both groups, B-mode ultrasound was performed by a physiatrist to measure the SCMT and UTMT and calculate the CSA of the AN. The correlation among SCMT, CSA of the AN, and UTMT in both groups was evaluated.The between-group comparison revealed that Group 1 had significantly greater SCMT, UTMT, and CSA of the AN on the affected side than Group 2 (P < .05). The intragroup comparison between the affected and unaffected sides also revealed that, in Group 1, the SCMT, UTMT, and CSA of the AN were significantly higher on the affected side than on the unaffected side (P < .05), whereas no significant differences were observed in Group 2. In Group 1, a positive correlation (r = 0.55) was observed between the UTMT and CSA of the AN on the affected side, but not observed between the SCMT and CSA of the AN.The findings of the study indicate that sternocleidomastoid muscle size may impact the thickness of the upper trapezius muscle via the accessory nerve in patients with congenital torticollis.
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Affiliation(s)
- Dong Rak Kwon
- Department of Rehabilitation Medicine, Catholic University of Daegu School of Medicine, 33 Duryugongwon-ro 17-gil, Nam-Gu, Daegu, South Korea
| | - Yoontae Kim
- Department of Physical Medicine and Rehabilitation, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Chungcheongnam-do, South Korea
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7
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Morgan R, Elliot I, Banala V, Dy C, Harris B, Ouellette EA. Pain Relief after Surgical Decompression of the Distal Brachial Plexus. J Brachial Plex Peripher Nerve Inj 2020; 15:e22-e32. [PMID: 33082844 PMCID: PMC7567639 DOI: 10.1055/s-0040-1716718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 07/26/2020] [Indexed: 11/24/2022] Open
Abstract
Background
Brachial plexopathy causes pain and loss of function in the affected extremity. Entrapment of the brachial plexus terminal branches within the surrounding connective tissue, or medial brachial fascial compartment, may manifest in debilitating symptoms. Open fasciotomy and external neurolysis of the neurovascular bundle in the medial brachial fascial compartment were performed as a surgical treatment for pain and functional decline in the upper extremity. The aim of this study was to evaluate pain outcomes after surgery in patients diagnosed with brachial plexopathy.
Methods
We identified 21 patients who met inclusion criteria. Documents dated between 2005 and 2019 were reviewed from electronic medical records. Chart review was conducted to collect data on visual analog scale (VAS) for pain, Semmes-Weinstein monofilament test (SWMT), and Medical Research Council (MRC) scale for muscle strength. Pre- and postoperative data was obtained. A paired sample
t
-test was used to determine statistical significance of pain outcomes.
Results
Pain severity in the affected arm was significantly reduced after surgery (pre: 6.4 ± 2.5; post: 2.0 ± 2.5;
p
< 0.01). Additionally, there was an increased response to SWMT after the procedure. More patients achieved an MRC rating score ≥3 and ≥4 in elbow flexion after surgery. This may be indicative of improved sensory and motor function.
Conclusion
Open fasciotomy and external neurolysis at the medial brachial fascial compartment is an effective treatment for pain when nerve continuity is preserved. These benefits were evident in patients with a prolonged duration elapsed since injury onset.
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Affiliation(s)
- Richard Morgan
- Department of Physical Medicine & Rehabilitation, Larkin Community Hospital, Miami, Florida, United States
| | - Iain Elliot
- Department of Orthopedics and Sports Medicine, University of Washington, Seattle, Washington, United States
| | - Vibhu Banala
- Department of Orthopedic Surgery, Montefiore Medical Center, Bronx, New York, United States
| | - Christopher Dy
- Department of Orthopedic Surgery, Washington University, School of Medicine, St. Louis, Missouri, United States
| | - Briana Harris
- Department of Orthopedic Surgery, Miami Orthopedics and Sports Medicine Institute, Baptist Health Medical Group South Florida, Miami, Florida, United States
| | - Elizabeth Anne Ouellette
- Department of Orthopedic Surgery, Miami Orthopedics and Sports Medicine Institute, Baptist Health Medical Group South Florida, Miami, Florida, United States
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8
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A proposal for a new headache classification system for general practitioners. Med Hypotheses 2020; 143:110103. [PMID: 32721801 DOI: 10.1016/j.mehy.2020.110103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/10/2020] [Accepted: 07/11/2020] [Indexed: 11/20/2022]
Abstract
We proposes a new method of headache classification, which is simpler for use in general practice and is based on a pathophysiological approach, in preference to the International Classification of Headache Disorders (ICHD) broad classification for headaches. In the ICDH classification, three main categories and numerous sub-categories and divisions are available with a view to addressing the symptoms and the aetiology of headache. However, the ICDH classification system is complex, with its many subdivisions, and it is cumbersome to use. Moreover, it is likely that not all medical professionals are readily familiar with it. A new classification system that is easy to learn and clinically user-friendly is necessary for primary care physicians to diagnose and classify headaches. We believe that our study makes a significant contribution to the literature because we propose a new method of classification for headaches that is based on clinical experience and addresses the pathogenesis of headaches.
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9
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Noh K, Jung JB, Seong JW, Kim DE, Kwon D, Kim Y. Thoracolumbar Junction Syndrome Accompanying Renal Artery Stenosis: A Case Report. Ann Rehabil Med 2020; 44:85-89. [PMID: 32130842 PMCID: PMC7056333 DOI: 10.5535/arm.2020.44.1.85] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 07/19/2019] [Indexed: 11/13/2022] Open
Abstract
Flank pain is a common reason for visits to the emergency room. The most common reason warranting hospital visits are urology-related problems. However, there are many other causes, such as musculoskeletal lesions, that difficult to achieve a correct diagnosis. Here, we describe a rare case of flank pain caused by thoracolumbar junction syndrome, accompanying renal artery stenosis. A 54-year-old male with hypertension presented with severe left flank pain for 1 week. Initially, he was diagnosed with left renal artery stenosis by computed tomography and decreased renal function on renal scan (Tc-99m DTPA). Although a stent was inserted into the left renal artery, flank pain persisted with only minor improvement. Through detailed physical examination, he was finally diagnosed with thoracolumbar junction syndrome. After three injections in the left deep paravertebral muscles at the T10–T12 levels, flank pain completely ceased. Clinicians must consider thoracolumbar junction syndrome, when treating patients with flank pain.
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Affiliation(s)
- Kyudong Noh
- Department of Physical Medicine and Rehabilitation, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon, Korea
| | - Jong Burm Jung
- Department of Physical Medicine and Rehabilitation, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan, Korea
| | | | - Doh-Eui Kim
- Department of Emergency Medicine, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan, Korea
| | - Dongrak Kwon
- Department of Rehabilitation Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Yuntae Kim
- Department of Physical Medicine and Rehabilitation, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan, Korea
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10
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Lefaucheur JP. New insights into the pathophysiology of primary hemifacial spasm. Neurochirurgie 2018; 64:87-93. [DOI: 10.1016/j.neuchi.2017.12.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/28/2017] [Accepted: 12/29/2017] [Indexed: 12/21/2022]
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Abstract
Current animal models of chronic peripheral nerve compression are mainly silicone tube models. However, the cross section of the rat sciatic nerve is not a perfect circle, and there are differences in the diameter of the sciatic nerve due to individual differences. The use of a silicone tube with a uniform internal diameter may not provide a reliable and consistent model. We have established a chronic sciatic nerve compression model that can induce demyelination of the sciatic nerve and lead to atrophy of skeletal muscle. In 3-week-old pups and adult rats, the sciatic nerve of the right hind limb was exposed, and a piece of surgical latex glove was gently placed under the nerve. N-butyl-cyanoacrylate was then placed over the nerve, and after it had set, another piece of glove latex was placed on top of the target area and allowed to adhere to the first piece to form a sandwich-like complex. Thus, a chronic sciatic nerve compression model was produced. Control pups with latex or N-butyl-cyanoacrylate were also prepared. Functional changes to nerves were assessed using the hot plate test and electromyography. Immunofluorescence and electron microscopy analyses of the nerves were performed to quantify the degree of neuropathological change. Masson staining was conducted to assess the degree of fibrosis in the gastrocnemius and intrinsic paw muscles. The pup group rats subjected to nerve compression displayed thermal hypoesthesia and a gradual decrease in nerve conduction velocity at 2 weeks after surgery. Neuropathological studies demonstrated that the model caused nerve demyelination and axonal irregularities and triggered collagen deposition in the epineurium and perineurium of the affected nerve at 8 weeks after surgery. The degree of fibrosis in the gastrocnemius and intrinsic paw muscles was significantly increased at 20 weeks after surgery. In conclusion, our novel model can reproduce the functional and histological changes of chronic nerve compression injury that occurs in humans and it will be a useful new tool for investigating the mechanisms underlying chronic nerve compression.
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Affiliation(s)
- Zhen-Yu Liu
- Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Zhen-Bing Chen
- Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Jiang-Hai Chen
- Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
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12
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Weerasinghe D, Menon P, Vucic S. Hyperpolarization-activated cyclic-nucleotide-gated channels potentially modulate axonal excitability at different thresholds. J Neurophysiol 2017; 118:3044-3050. [PMID: 28904107 DOI: 10.1152/jn.00576.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 09/06/2017] [Accepted: 09/12/2017] [Indexed: 11/22/2022] Open
Abstract
Hyperpolarization-activated cyclic-nucleotide-gated (HCN) channels mediate differences in sensory and motor axonal excitability at different thresholds in animal models. Importantly, HCN channels are responsible for voltage-gated inward rectifying (Ih) currents activated during hyperpolarization. The Ih currents exert a crucial role in determining the resting membrane potential and have been implicated in a variety of neurological disorders, including neuropathic pain. In humans, differences in biophysical properties of motor and sensory axons at different thresholds remain to be elucidated and could provide crucial pathophysiological insights in peripheral neurological diseases. Consequently, the aim of this study was to characterize sensory and motor axonal function at different threshold. Median nerve motor and sensory axonal excitability studies were undertaken in 15 healthy subjects (45 studies in total). Tracking targets were set to 20, 40, and 60% of maximum for sensory and motor axons. Hyperpolarizing threshold electrotonus (TEh) at 90-100 ms was significantly increased in lower threshold sensory axons times (F = 11.195, P < 0.001). In motor axons, the hyperpolarizing current/threshold (I/V) gradient was significantly increased in lower threshold axons (F = 3.191, P < 0.05). The minimum I/V gradient was increased in lower threshold motor and sensory axons. In conclusion, variation in the kinetics of HCN isoforms could account for the findings in motor and sensory axons. Importantly, assessing the function of HCN channels in sensory and motor axons of different thresholds may provide insights into the pathophysiological processes underlying peripheral neurological diseases in humans, particularly focusing on the role of HCN channels with the potential of identifying novel treatment targets.NEW & NOTEWORTHY Hyperpolarization-activated cyclic-nucleotide-gated (HCN) channels, which underlie inward rectifying currents (Ih), appear to mediate differences in sensory and motor axonal properties. Inward rectifying currents are increased in lower threshold motor and sensory axons, although different HCN channel isoforms appear to underlie these changes. While faster activating HCN channels seem to underlie Ih changes in sensory axons, slower activating HCN isoforms appear to be mediating the differences in Ih conductances in motor axons of different thresholds. The differences in HCN gating properties could explain the predilection for dysfunction of sensory and motor axons in specific neurological diseases.
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Affiliation(s)
| | - Parvathi Menon
- Department of Neurology, Westmead Hospital, Sydney, Australia; and.,Westmead Clinical School, The University of Sydney, Sydney, Australia
| | - Steve Vucic
- Department of Neurology, Westmead Hospital, Sydney, Australia; and .,Westmead Clinical School, The University of Sydney, Sydney, Australia
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13
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Otani Y, Yermakov LM, Dupree JL, Susuki K. Chronic peripheral nerve compression disrupts paranodal axoglial junctions. Muscle Nerve 2016; 55:544-554. [PMID: 27463510 DOI: 10.1002/mus.25273] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 07/13/2016] [Accepted: 07/26/2016] [Indexed: 11/06/2022]
Abstract
INTRODUCTION Peripheral nerves are often exposed to mechanical stress leading to compression neuropathies. The pathophysiology underlying nerve dysfunction by chronic compression is largely unknown. METHODS We analyzed molecular organization and fine structures at and near nodes of Ranvier in a compression neuropathy model in which a silastic tube was placed around the mouse sciatic nerve. RESULTS Immunofluorescence study showed that clusters of cell adhesion complex forming paranodal axoglial junctions were dispersed and overlapped frequently with juxtaparanodal components. These paranodal changes occurred without internodal myelin damage. The distribution and pattern of paranodal disruption suggests that these changes are the direct result of mechanical stress. Electron microscopy confirmed loss of paranodal axoglial junctions. CONCLUSIONS Our data show that chronic nerve compression disrupts paranodal junctions and axonal domains required for proper peripheral nerve function. These results provide important clues toward better understanding of the pathophysiology underlying nerve dysfunction in compression neuropathies. Muscle Nerve 55: 544-554, 2017.
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Affiliation(s)
- Yoshinori Otani
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, 3640 Colonel Glenn Highway, Dayton, Ohio, 45435, USA
| | - Leonid M Yermakov
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, 3640 Colonel Glenn Highway, Dayton, Ohio, 45435, USA
| | - Jeffrey L Dupree
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Keiichiro Susuki
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, 3640 Colonel Glenn Highway, Dayton, Ohio, 45435, USA
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Sung JY, Tani J, Hung KS, Lui TN, Lin CSY. Sensory axonal dysfunction in cervical radiculopathy. J Neurol Neurosurg Psychiatry 2015; 86:640-5. [PMID: 25143629 DOI: 10.1136/jnnp-2014-308088] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 08/01/2014] [Indexed: 11/03/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate changes in sensory axonal excitability in the distal nerve in patients with cervical radiculopathy. METHODS The patients were classified by the findings of cervical MRI into two subgroups: 22 patients with C6/7 root compression and 25 patients with cervical cord and root compression above/at C6/7. Patients were investigated using conventional nerve conduction studies (NCS) and nerve excitability testing. Sensory nerve excitability testing was undertaken with stimulation at the wrist and recording from digit II (dermatome C6/7). The results were compared with healthy controls. Both preoperative and postoperative tests were performed if the patient underwent surgery. RESULTS Sensory axonal excitability was significantly different in both cohorts compared with healthy controls, including prolonged strength-duration time constant, reduced S2 accommodation, increased threshold electrotonus hyperpolarisation (TEh (90-100 ms)), and increased superexcitability. The changes in these excitability indices are compatible with axonal membrane hyperpolarisation. In five patients who underwent surgery, the postoperative sensory excitability was tested after 1 week, and showed significant changes in TE (TEh (90-100 ms) and TEh slope, p<0.05) between presurgery and postsurgery. CONCLUSIONS The present study demonstrated distal nerve axonal hyperpolarisation in patients with cervical radiculopathy. These findings suggest that the hyperpolarised pattern might be due to Na(+)-K(+) ATPase overactivation induced by proximal ischaemia, or could reflect the remyelinating process. Distal sensory axons were hyperpolarised even though there were no changes in NCS, suggesting that nerve excitability testing may be more sensitive to clinical symptoms than NCS in patients with cervical radiculopathy.
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Affiliation(s)
- Jia-Ying Sung
- Department of Neurology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan Department of Neurology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Jowy Tani
- Department of Neurology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Kuo-Sheng Hung
- Division of Neurosurgery, Department of Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan Department of Neurosurgery, Clinical Research Center, Graduate Institute of Injury Prevention and Control, Taipei Medical University, Wan Fang Hospital, Taipei, Taiwan
| | - Tai-Ngar Lui
- Division of Neurosurgery, Department of Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Cindy Shin-Yi Lin
- Department of Neurology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan Translational Neuroscience, Department of Physiology, School of Medicine Science, Faculty of Medicine, University of New South Wales, Sydney, Australia
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