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Neurosciences (Riyadh, Saudi Arabia) Jan 2015Carpal tunnel syndrome (CTS) is the most common median nerve neuropathy, accounting for 90% of all neuropathies. Carpal tunnel syndrome presents in 3.8% of the general... (Review)
Review
Carpal tunnel syndrome (CTS) is the most common median nerve neuropathy, accounting for 90% of all neuropathies. Carpal tunnel syndrome presents in 3.8% of the general population, with a higher prevalence among women. There are several risk factors associated with CTS, including both medical and non medical factors. The pathophysiologic mechanisms involved in the median nerve compression and traction are thought to be complex, and as yet are not fully understood. The present review aimed to provide an overview of the pathophysiology of median nerve neuropathy in the carpal tunnel, and subsequent development of CTS.
Topics: Carpal Tunnel Syndrome; Humans; Median Nerve; Neural Conduction; Peripheral Nerve Injuries; Prevalence; Sex Factors
PubMed: 25630774
DOI: No ID Found -
Brain : a Journal of Neurology Apr 2017Carpal tunnel syndrome is the most common entrapment neuropathy, affecting the median nerve at the wrist. Acupuncture is a minimally-invasive and conservative... (Randomized Controlled Trial)
Randomized Controlled Trial
Carpal tunnel syndrome is the most common entrapment neuropathy, affecting the median nerve at the wrist. Acupuncture is a minimally-invasive and conservative therapeutic option, and while rooted in a complex practice ritual, acupuncture overlaps significantly with many conventional peripherally-focused neuromodulatory therapies. However, the neurophysiological mechanisms by which acupuncture impacts accepted subjective/psychological and objective/physiological outcomes are not well understood. Eligible patients (n = 80, 65 female, age: 49.3 ± 8.6 years) were enrolled and randomized into three intervention arms: (i) verum electro-acupuncture 'local' to the more affected hand; (ii) verum electro-acupuncture at 'distal' body sites, near the ankle contralesional to the more affected hand; and (iii) local sham electro-acupuncture using non-penetrating placebo needles. Acupuncture therapy was provided for 16 sessions over 8 weeks. Boston Carpal Tunnel Syndrome Questionnaire assessed pain and paraesthesia symptoms at baseline, following therapy and at 3-month follow-up. Nerve conduction studies assessing median nerve sensory latency and brain imaging data were acquired at baseline and following therapy. Functional magnetic resonance imaging assessed somatotopy in the primary somatosensory cortex using vibrotactile stimulation over three digits (2, 3 and 5). While all three acupuncture interventions reduced symptom severity, verum (local and distal) acupuncture was superior to sham in producing improvements in neurophysiological outcomes, both local to the wrist (i.e. median sensory nerve conduction latency) and in the brain (i.e. digit 2/3 cortical separation distance). Moreover, greater improvement in second/third interdigit cortical separation distance following verum acupuncture predicted sustained improvements in symptom severity at 3-month follow-up. We further explored potential differential mechanisms of local versus distal acupuncture using diffusion tensor imaging of white matter microstructure adjacent to the primary somatosensory cortex. Compared to healthy adults (n = 34, 28 female, 49.7 ± 9.9 years old), patients with carpal tunnel syndrome demonstrated increased fractional anisotropy in several regions and, for these regions we found that improvement in median nerve latency was associated with reduction of fractional anisotropy near (i) contralesional hand area following verum, but not sham, acupuncture; (ii) ipsilesional hand area following local, but not distal or sham, acupuncture; and (iii) ipsilesional leg area following distal, but not local or sham, acupuncture. As these primary somatosensory cortex subregions are distinctly targeted by local versus distal acupuncture electrostimulation, acupuncture at local versus distal sites may improve median nerve function at the wrist by somatotopically distinct neuroplasticity in the primary somatosensory cortex following therapy. Our study further suggests that improvements in primary somatosensory cortex somatotopy can predict long-term clinical outcomes for carpal tunnel syndrome.
Topics: Acupuncture Points; Acupuncture Therapy; Adult; Aged; Brain Mapping; Carpal Tunnel Syndrome; Diffusion Magnetic Resonance Imaging; Electroacupuncture; Female; Hand; Humans; Male; Median Nerve; Middle Aged; Neural Conduction; Pain Measurement; Somatosensory Cortex; Treatment Outcome; White Matter; Wrist; Young Adult
PubMed: 28334999
DOI: 10.1093/brain/awx015 -
Journal of Ultrasound Sep 2020Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy of peripheral nerves, with an incidence of 1-3 patients in 1000. CTS typically occurs between 45... (Review)
Review
Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy of peripheral nerves, with an incidence of 1-3 patients in 1000. CTS typically occurs between 45 and 60 years of age, and it is more frequent in women than in men. The main cause of CTS is chronic compression of the median nerve and ischemic suffering secondary to increased pressure in the carpal tunnel. There are many possible causes of CTS, which can be differentiated into idiopathic causes, which include most cases, and secondary causes. Classical CTS diagnosis is based on the patient's clinical examination and electrophysiological tests, such as electromyography and nerve conduction studies. The latter are helpful for determining the site of nerve compression, assessing its severity, monitoring the course of the disease after therapy, and excluding other causes of median nerve pain, such as cervical radiculopathies, brachial plexopathies, polyneuropathy, or other forms of mononeuropathies. However, clinical examination and electrophysiological tests are not able to differentiate idiopathic forms from secondary forms of CTS, and discrepancies are possible between clinical examination and electrophysiological tests (false negatives). Ultrasound examination is able to recognize most of the secondary forms of CTS. It can evaluate the morphological alterations of the nerve and correlate them with the severity of nerve suffering in all cases, even idiopathic ones, with a sensitivity and specificity equal to those of electrophysiological tests. It can also highlight some anatomical predisposing variants or conditions that may represent contraindications to minimally invasive treatments. Ultrasound examination also plays a fundamental role in evaluating patients with an unfavorable outcome after surgical treatment.
Topics: Carpal Tunnel Syndrome; Humans; Median Nerve; Ultrasonography
PubMed: 32323256
DOI: 10.1007/s40477-020-00460-z -
Hawai'i Journal of Health & Social... Nov 2019Carpal tunnel syndrome costs the United States billions of dollars each year. The majority of patients are industrial workers, females, and the elderly who first present...
Carpal tunnel syndrome costs the United States billions of dollars each year. The majority of patients are industrial workers, females, and the elderly who first present to their primary care physicians. Therefore, it is essential that the primary care physician understand this syndrome in order to diagnose and direct treatment. Here we present a review of the anatomy, pathophysiology, diagnosis, and current treatment of carpal tunnel syndrome that is relevant for the treating primary care physician. In addition, we discuss the role of the primary care physician in the diagnosis, management, and treatment of carpal tunnel syndrome. The aim of this review is to improve the integrated care of those patients suffering from carpal tunnel syndrome.
Topics: Age Factors; Carpal Tunnel Syndrome; Female; Humans; Male; Median Nerve; Middle Aged; Physicians, Primary Care; Practice Guidelines as Topic; Sex Factors; United States
PubMed: 31773104
DOI: No ID Found -
Current Hypertension Reports Aug 2016Hypertension continues to be a major contributor to global morbidity and mortality, fuelled by an abundance of patients with uncontrolled blood pressure despite the... (Review)
Review
Hypertension continues to be a major contributor to global morbidity and mortality, fuelled by an abundance of patients with uncontrolled blood pressure despite the multitude of pharmacological options available. This may occur as a consequence of true resistant hypertension, through an inability to tolerate current pharmacological therapies, or non-adherence to antihypertensive medication. In recent years, there has been a rapid expansion of device-based therapies proposed as novel non-pharmacological approaches to treating resistant hypertension. In this review, we discuss seven novel devices-renal nerve denervation, baroreflex activation therapy, carotid body ablation, central iliac arteriovenous anastomosis, deep brain stimulation, median nerve stimulation, and vagal nerve stimulation. We highlight how the devices differ, the varying degrees of evidence available to date and upcoming trials. This review also considers the possible factors that may enable appropriate device selection for different hypertension phenotypes.
Topics: Antihypertensive Agents; Arteriovenous Shunt, Surgical; Baroreflex; Blood Pressure; Carotid Body; Deep Brain Stimulation; Electric Stimulation Therapy; Humans; Hypertension; Iliac Artery; Iliac Vein; Median Nerve; Sympathectomy; Vagus Nerve Stimulation
PubMed: 27370788
DOI: 10.1007/s11906-016-0670-5 -
Clinical Biomechanics (Bristol, Avon) Jan 2020Carpal tunnel and median nerve dynamically change with wrist motion. The purpose of this study was to investigate the morphological changes and positional migration of...
BACKGROUND
Carpal tunnel and median nerve dynamically change with wrist motion. The purpose of this study was to investigate the morphological changes and positional migration of the carpal arch and median nerve, as well as nerve-arch positional relationship associated with wrist deviation in healthy volunteers.
METHODS
Twenty asymptomatic male volunteers performed wrist motion from neutral to deviated positions combining flexion-extension and radioulnar deviation. Ultrasound images of the carpal arch and median nerve at the distal carpal tunnel were collected during wrist motion. Morphological and positional parameters of the carpal arch and median nerve were derived from the ultrasound images.
FINDINGS
Carpal arch height, area, and palmar bowing of the transverse carpal ligament (TCL) increased with flexion related wrist motion and decreased with extension related motion (P < 0.05). Arch width increased with radial flexion and decreased with extension and ulnar extension (P < 0.05). Median nerve circularity increased with flexion and radial flexion but decreased with extension, ulnar extension, and ulnar deviation (P < 0.05). Nerve centroid displaced ulnarly with radial deviation, radial flexion, and radial extension and displaced radially with ulnar deviation, ulnar flexion, and ulnar extension (P < 0.05). Nerve centroid displaced in the dorsal direction with flexion and radial flexion, but in the palmar direction with extension (P < 0.05). Nerve-TCL distance increased with flexion related motion and decreased with extension relation motion (P < 0.05).
INTERPRETATION
The current study advances our understanding the effect of wrist motion on the carpal tunnel and its contents, which has implications for pathomorphological and pathokinematic changes associated with wrist disorders.
Topics: Adult; Carpal Bones; Female; Healthy Volunteers; Humans; Ligaments, Articular; Male; Median Nerve; Motion; Radius; Range of Motion, Articular; Ultrasonography; Wrist; Wrist Joint
PubMed: 31733628
DOI: 10.1016/j.clinbiomech.2019.10.024 -
Clinical Neurophysiology : Official... Jul 2022To measure the neuromagnetic fields of carpal tunnel syndrome patients after electrical digital nerve stimulation and evaluate median nerve function with high spatial...
OBJECTIVE
To measure the neuromagnetic fields of carpal tunnel syndrome patients after electrical digital nerve stimulation and evaluate median nerve function with high spatial resolution.
METHODS
A superconducting quantum interference device magnetometer system was used to record neuromagnetic fields at the carpal tunnel after electrical stimulation of the middle digital nerve in 10 hands of nine patients with carpal tunnel syndrome. The patients were diagnosed based on symptoms (numbness, tingling, and pain) supported by a positive Phalen or Tinel sign. A novel technique was applied to remove stimulus-induced artifacts, and current distributions were calculated using a spatial filter algorithm and superimposed on X-ray.
RESULTS
In 6 of the 10 hands, the amplitude of the inward current waveform attenuated to <70% or the nerve conduction velocity was <40 m/s. The results of conventional nerve conduction studies were normal for two of these six hands. All four hands that could not be diagnosed by magnetoneurography had severe carpal tunnel syndrome superimposed on peripheral neuropathy secondary to comorbidities.
CONCLUSIONS
Technical improvements enabled magnetoneurography to noninvasively visualize the electrophysiological nerve activity in carpal tunnel syndrome patients.
SIGNIFICANCE
Magnetoneurography may have the potential to contribute to the detailed diagnosis of various peripheral nerve disorders.
Topics: Carpal Tunnel Syndrome; Humans; Median Nerve; Neural Conduction; Peripheral Nervous System Diseases; Wrist
PubMed: 35489208
DOI: 10.1016/j.clinph.2022.03.021 -
BMC Neuroscience Aug 2020When planning nerve conduction studies using animal models, the sciatic nerve is often used and the upper extremity nerves are not preferred due to the size of...
BACKGROUND
When planning nerve conduction studies using animal models, the sciatic nerve is often used and the upper extremity nerves are not preferred due to the size of laboratory animals. This study aimed to present the method and mean values of median nerve conduction studies in laboratory rabbits. Fifty-five six-month-old male New Zealand white rabbits weighing 2 to 2.5 kg were included in nerve conduction studies performed under anesthesia. The compound muscle action potential amplitude and distal latency values were recorded for the median motor nerve with the electrodes placed on the flexor digitorum superficialis muscle and tendon.
RESULTS
A total of 110 median nerves were evaluated. The mean amplitude of the median nerve was 30.6 ± 6.8, mV the median nerve distal latency was 1.3 ± 0.2 ms, and the mean intensity of stimulation inducing a response was 2.5 ± 1 mA.
CONCLUSIONS
The mean values obtained by the median motor nerve conduction method in this study can act as a guide for future nerve interventions undertaken in the upper extremities.
Topics: Action Potentials; Animals; Female; Male; Median Nerve; Muscle, Skeletal; Neural Conduction; Rabbits; Reaction Time
PubMed: 32807101
DOI: 10.1186/s12868-020-00584-2 -
Journal of Neural Engineering Jul 2022. Accurate identification of functional cortical regions is essential in neurological resection. The central sulcus (CS) is an important landmark that delineates...
. Accurate identification of functional cortical regions is essential in neurological resection. The central sulcus (CS) is an important landmark that delineates functional cortical regions. Median nerve stimulation (MNS) is a standard procedure to identify the position of the CS intraoperatively. In this paper, we introduce an automated procedure that uses MNS to rapidly localize the CS and create functional somatotopic maps.. We recorded electrocorticographic signals from 13 patients who underwent MNS in the course of an awake craniotomy. We analyzed these signals to develop an automated procedure that determines the location of the CS and that also produces functional somatotopic maps.. The comparison between our automated method and visual inspection performed by the neurosurgeon shows that our procedure has a high sensitivity (89%) in identifying the CS. Further, we found substantial concordance between the functional somatotopic maps generated by our method and passive functional mapping (92% sensitivity).. Our automated MNS-based method can rapidly localize the CS and create functional somatotopic maps without imposing additional burden on the clinical procedure. With additional development and validation, our method may lead to a diagnostic tool that guides neurosurgeons and reduces postoperative morbidity in patients undergoing resective brain surgery.
Topics: Brain Mapping; Cerebral Cortex; Craniotomy; Electrocorticography; Humans; Median Nerve
PubMed: 35785769
DOI: 10.1088/1741-2552/ac7dfd -
ARP Rheumatology 2023In this study, our primary aim was to compare ultrasound (US) findings of the median nerve between rheumatoid arthritis (RA) with carpal tunnel syndrome (CTS)...
AIM
In this study, our primary aim was to compare ultrasound (US) findings of the median nerve between rheumatoid arthritis (RA) with carpal tunnel syndrome (CTS) (RA(+)CTS), RA without CTS (RA(-)CTS) and healthy controls (HC) and to determine the optimal US parameters to detect the presence of CTS in RA patients.
METHODS
65 RA patients and 25 HC patients were included in this study. The diagnosis of CTS was made according to the clinical history and physical examination of the participants. Median nerve cross-sectional area(CSA) was measured at the carpal tunnel inlet(CTI), outlet(CTO), and forearm level by the US. In addition, anteroposterior(AP) and mediolateral(ML) diameters of the median nerve were measured. After the measurements, wrist-to-forearm ratio, wrist-to-forearm difference, and flattening ratio were calculated. The presence of tenosynovitis was investigated.
RESULTS
CTS was detected in 26(40.0%) of 65 RA patients who participated in the study. CTS was detected in 43(35.2%) of 122 wrists of 65 RA patients. CTI CSA, CTO CSA, forearm CSA, anteroposterior/mediolateral diameter, wrist-to-forearm ratio, wrist-to-forearm difference, and flattening ratio were significantly higher in RA(+)CTS than in RA(-)CTS and HC(p<0.01). In addition, CDAI and CTI CSA(r=0.322, p<0.01), CTO CSA(r=0.301, p<0.01), CTI-to-forearm ratio(r=0.345, p<0.001), CTI-to-forearm difference(r=0.362, p<0.01) and CTO-Forearm difference(r=0.304, p<0.01) moderate correlation was found between. The frequency of tenosynovitis was higher in wrists with CTS than in wrists without CTS (p<0.05).
CONCLUSION
While the presence of CTS in RA patients is sonographically evaluated, it may be useful to evaluate parameters such as CTI-to-forearm difference, ratio, and CTI ML diameter rather than just sticking to CTI CSA during diagnosis. Correlations of these parameters with disease activity can also be noted.
Topics: Humans; Carpal Tunnel Syndrome; Tenosynovitis; Ultrasonography; Median Nerve; Arthritis, Rheumatoid
PubMed: 38174753
DOI: No ID Found