Median Nerve Cross-sectional Area Research Articles

DİABETİK GEBELERDE KARPAL TÜNELİN ULTRASONOGRAFİK DEĞERLENDİRİLMESİ

Objective: To determine the ultrasonography (USG) values of median nerve cross-sectional area (MN-CSA) in pregnant women with and without diabetes mellitus (DM) to confirm carpal tunnel syndrome (CTS).
 Methods: We prospectively studied pregnant women who have been diagnosed with pregestational type 1 and type 2 DM or gestational DM (GDM) due to positive GDM screening tests. One-step GDM screening (2 h - 75 g oral glucose tolerance test (OGTT)) was used at 24–28 weeks of gestation and diagnosis of GDM. MN was identified at the level of distal wrist crease in transverse sections with USG and maximal MN-CSA was calculated then, asked the patient complaints about her hand (paraesthesia, pain, numbness). The DM group was compared to the control group according to age, week of pregnancy, weight gain during pregnancy, MN-CSA, and presence of compliments.
 Results: There were 107 DM pregnant women and 113 controls in the study group. The median value of MN-CSA was higher in the DM group than in the control group (p< 0,001). There was no difference between groups in terms of DM subgroups and insulin requirement. Hand pain is significantly frequent in the DM group than in controls. There has been a positive correlation between weight gain during pregnancy and MN-CSA (p =0,011; r=0,245).
 Conclusion: USG can be a first-line diagnostic test for CTS in the diabetic pregnant population, as recommended for the general population before. Both pregnancy and DM are stated as risk factors for CTS, these patients must be evaluated more carefully about this issue and proper advices should be given to improve their life quality.

Influence of Disease Activity and Body Composition Parameters on Cross-Sectional Area of the Median Nerve in Acromegalic Patients.

Carpal tunnel syndrome (CTS) is neuropathy that occurs due to compression of the median nerve in the carpal tunnel. Acromegaly is one of the important causes of CTS. The aim of this study was to examine median nerve with ultrasound in acromegalic patients and to assess the relationship with activity, duration of disease and body composition parameters. We prospectively examined the cross-sectional area (CSA) of the median nerve with high-resolution ultrasound in 107 acromegalic patients (70 females and 37 males) and 107 healthy controls (70 females and 37 males) matched for age, gender, and BMI. Body composition parameters were assessed by dual-energy X-ray absorptiometry (DXA). The Student t-tests and Pearson correlation were used for data analysis. The cross sectional area of the median nerve was increased in acromegalic patients compared to controls (11.9 ± 4.8 mm2 vs. 7.7 ± 2.4 mm2, P < 0.001). Positive correlation was found between IGF-1 levels and CSA in the acromegalic group (R = 0.400, P < 0.001). Relationship between CSA and duration of acromegaly was not confirmed. In acromegalic patients, BMI correlated with the CSA (R = 0.294, P = 0.002). There was no significant difference in BMI, fat mass between the acromegalic and control group, but lean mass was higher in acromegalic patients compared with controls (54.8 ± 13.3 vs. 51 ± 11.6, P = 0.047). Lean mass and LMI (total body lean mass/height) positively correlated with CSA in acromegalic patients (R = 0.340, P < 0.001; R = 0.424, P < 0.001). No correlation was observed between fat mass and CSA of median nerve in all groups. We confirmed the enlargement of the median nerve in acromegalic patients. This enlargement is proportional to the degree of IGF-1 levels and is not dependent on the duration of the disease. The enlargement of the median nerve in acromegalic patients also depends on lean body mass and is not dependent on fat body mass.

Comprehensive Assessment of Ultrasound's Role in Carpal Tunnel Syndrome in Reference to Electromyography.

Carpal tunnel syndrome (CTS) is the most common peripheral mononeuropathy related to entrapment syndrome. An increase in the median nerve cross-sectional area (CSA) is visualized using ultrasound (US) imaging for CTS patients. This study aims to correlate, for the first time in the state of Qatar, the findings of US imaging and electromyography (EMG) in patients with CTS for diagnostic and classification purposes. First, US CSA was numerically obtained from patients' records. Second, EMG findings were gathered as normal, mild, moderate, and severe CTS. After that, we performed a different statistical approach than those used in the literature, using one-way analysis of variance (ANOVA) and post hoc tests for the final analysis. In summary, we found that the US seems unable to differentiate some normal from mild CTS cases; however, it appears to be excellent at differentiating moderate from severe CTS cases.

Influence of Disease Activity and Body Composition Parameters on Cross-Sectional Area of the Median Nerve in Acromegalic Patients

Carpal tunnel syndrome (CTS) is neuropathy that occurs due to compression of the median nerve in the carpal tunnel. Acromegaly is one of the important causes of CTS. The aim of this study was to examine median nerve with ultrasound in acromegalic patients and to assess the relationship with activity, duration of disease and body composition parameters. We prospectively examined the cross-sectional area (CSA) of the median nerve with high-resolution ultrasound in 107 acromegalic patients – control group (70 females and 37 males) and 107 healthy controls (70 females and 37 males) matched for age, gender, and BMI. Body composition parameters were assessed by dual-energy X-ray absorptiometry (DXA). The Student t-tests and Pearson correlation were used for data analysis. The cross sectional area of the median nerve was increased in acromegalic patients compared to controls (11.9±4.8 mm2 vs. 7.7±2.4 mm2, P&lt;0.001). Positive correlation was found between IGF-1 levels and CSA in the acromegalic group (R = 0.400, P&lt;0.001). Relationship between CSA and duration of acromegaly was not confirmed. In acromegalic patients, BMI correlated with the CSA (R=0.294, P=0.002). There was no significant difference in BMI, fat mass between the acromegalic and control group, but lean mass was higher in acromegalic patients compared with controls (54.8±13.3 vs. 51±11.6, P=0.047). Lean mass and LMI (total body lean mass/height) positively correlated with CSA in acromegalic patients (R=0.340, P&lt;0.001; R=0.424, P&lt;0.001). No correlation was observed between fat mass and CSA of median nerve in all groups. We confirmed the enlargement of the median nerve in acromegalic patients. This enlargement is proportional to the degree of IGF-1 levels and is not dependent on the duration of the disease. The enlargement of the median nerve in acromegalic patients also depends on lean body mass and is not dependent on fat body mass.

Median Nerve and Carpal Tunnel Morphology Before and After Endoscopic Carpal Tunnel Release: A 6-Year Follow-up Study.

Our purpose was to describe structural and morphological features of the median nerve and carpal tunnel on magnetic resonance imaging (MRI) studies obtained before, immediately after, 6 weeks after, and 6 years after endoscopic carpal tunnel release (ECTR). In this prospective cohort study, 9 patients with a diagnosis of carpal tunnel syndrome (CTS) underwent ECTR. Standardized MRI studies were obtained before ECTR, immediately after ECTR, and 6 weeks and 6 years after surgery. Structural and morphological features of the median nerve and carpal tunnel were measured and assessed for each study with comparisons made between each time point. All 9 patients had complete symptom resolution postoperatively. On the immediate postoperative MRI, there was a discrete gap in the transverse carpal ligament in all patients. There was retinacular regrowth noted at 6 weeks in all cases. The median nerve cross-sectional area and the anterior-posterior dimension of the carpal tunnel at the level of the hamate increased immediately after surgery and these changes were maintained at 6 years. We defined structural and morphological changes on MRI for the median nerve and carpal tunnel in patients with continued symptom resolution 6 years after ECTR. Changes in median nerve and carpal tunnel morphology that occur immediately after surgery remain unchanged at mid-term follow-up in asymptomatic patients. Established imaging criteria for CTS may not apply to postoperative patients. Magnetic resonance imaging appears to be of limited clinical utility in the workup of persistent or recurrent CTS.

Median nerve ultrasonography examination correlates with electrodiagnostic studies for the diagnosis of moderate to severe carpal tunnel syndrome.

The aim of the study was to investigate the associations of cross-sectional area (CSA) of the median nerve measured by ultrasonography, the median to ulnar nerve ratio (MUR), the median to ulnar nerve difference (MUD) and the ratio of CSA of the median nerve to height squared (MHS) in relation to electrodiagnostic classification of moderate and severe carpal tunnel syndrome (CTS) and thus to identify patients suitable for surgical treatment. A prospective study was conducted in patients aged ≥ 18 years who underwent both median and ulnar nerve ultrasonography and electrodiagnostic studies (EDS). 124 wrists of 62 patients were examined. The patients' characteristics were acquired through a questionnaire. CTS was diagnosed using EDS and classified according to the guidelines of the Czech Republic Association of Electrodiagnostic Medicine. The CSA of the median nerve and of the ulnar nerve were measured at the carpal tunnel inlet. Median nerve CSA at the tunnel inlet ≥ 12 mm2 correlates with electrodiagnostic classification of moderate to severe carpal tunnel syndrome. At this cut-off value, the sensitivity of ultrasonography is 82.4%, its specificity is 87.7%, the positive predictive value is 82.4%, the negative predictive value is 87.7%. MUD, MUR and MHS perform worse than the median nerve CSA, as shown by their lower area under the receiver operating characteristic curve. Ultrasound could help us indicate surgical treatment for CTS, especially in patients with clinical findings. Our results suggest a cut-off value of CSA at the tunnel inlet of ≥ 12mm2.

The value of sonographic quantitative parameters in the diagnosis of carpal tunnel syndrome in the Vietnamese population.

ObjectiveTo examine the value of ultrasound (US) in the diagnosis of carpal tunnel syndrome (CTS) in the Vietnamese population.MethodsThis prospective cross-sectional study involved 42 wrists of 25 patients with idiopathic CTS evaluated by US. In addition, 38 wrists of 22 healthy volunteers were included as the control group.ResultsSignificant differences in the median nerve cross-sectional area (CSA) at different levels were found between patients with CTS and controls. Using a cut-off value of 9.5 mm2 for the median nerve CSA at the pisiform (p-CSA), US had a sensitivity and specificity of 95.2% and 97.4%, respectively, for the diagnosis of CTS. Area under the curve analysis revealed a sensitivity and specificity of 100% and 95.4%, respectively, for the prediction of severe CTS using a p-CSA of >15.5 mm2.ConclusionsThe median nerve CSA is a highly accurate parameter in the diagnosis of CTS. We recommend using a p-CSA of >9.5 mm2 as a diagnostic criterion for CTS and a p-CSA of >15.5 mm2 as a marker for severe CTS in the Vietnamese population.Research Registry number: 7261

Cross-Sectional Area of the Median Nerve as a Prognostic Indicator in Carpal Tunnel Syndrome Treated With Local Steroid Injection

Local steroid injection is an effective treatment modality for carpal tunnel syndrome. This study aimed to investigate the success rate of ultrasonography-guided local steroid injection and determine the prognostic value of the cross-sectional area (CSA) of the median nerve for steroid injection. We retrospectively evaluated 40 patients with carpal tunnel syndrome whose median nerve CSA was >15 mm2 (large-CSA group; n= 16) or ≤15 mm2 (small-CSA group; n= 24). The CSA was measured using ultrasonography, and all the patients were treated with ultrasonography-guided corticosteroid injection. Demographic characteristics, symptoms, initial QuickDASH score, Boston Carpal Tunnel Questionnaires, and results of the nerve conduction study were assessed at baseline. Treatment success was defined in this study as the absence of symptom recurrence within the entire follow-up period. The treatment success rate was 45% (n= 18) after an average follow-up of 16 months. Overall, 11 patients (28%) underwent carpal tunnel release on an average of 11 months after steroid injection. The large-CSA group showed a significantly worse grade of electrodiagnostic testing at baseline than did the small-CSA group; however, there was no significant difference in final Boston Carpal Tunnel Questionnaires symptom score (1.7 vs 1.8, respectively) and the rate of continued treatment success at the last follow-up (42% vs 50%, respectively). The proportions of patients who required carpal tunnel decompression were 29% and 25% in the small-CSA and large-CSA groups, respectively. Local steroid injection for carpal tunnel syndrome has an overall success rate of 45% after a mean follow-up of 16 months. Preinjection CSA was not associated with whether the steroid injection was considered successful. This indicates that increased median nerve CSA does not preclude the possibility of symptomatic relief after a local steroid injection. Therapeutic IV.

Cross-sectional area of the vagus nerve on carotid duplex ultrasound and atrial fibrillation in acute stroke: A retrospective analysis.

IntroductionThe autonomic nervous system, including the vagus nerve, is associated with the development of atrial fibrillation (AF). However, the association between the cross-sectional area (CSA) of the vagus nerve on ultrasound and the presence of AF has not been fully clarified. This study investigated the association between vagus nerve CSA and the presence of AF in patients with acute stroke.MethodsWe retrospectively reviewed 150 consecutive patients with ischemic stroke or transient ischemic attack. Vagus nerve CSA was evaluated by carotid ultrasonography on the axial view at the thyroid gland level. Univariate and multivariable analyses were performed to examine the association between vagus nerve CSA and AF.ResultsOf 133 patients included in the analysis, 31 (23.3%) were diagnosed with AF before hospital discharge. The median right vagus nerve CSA was significantly smaller in patients with AF than in patients without AF (p = 0.03). However, there was no significant difference in median left vagus nerve CSA. Multivariable logistic regression analysis revealed that log transformed and quintiled brain natriuretic peptide level (odds ratio [OR], 5.03; 95% confidence interval [CI], 2.43–10.40) and right vagus nerve CSA (OR, 0.33; 95% CI, 0.12–0.91) were independent predictors of AF.Discussion/conclusionSmaller right vagus nerve CSA in carotid ultrasonography was an independent predictor of AF in patients with ischemic stroke or transient ischemic attack, suggesting that patients with small right vagus nerve CSA should be closely monitored for development of AF.

High-resolution neuromuscular ultrasound-based diagnosis of carpal tunnel syndrome in a sample of Egyptian population

BackgroundCarpal tunnel syndrome is the commonest entrapment neuropathy. The cut-off point of cross-sectional area to diagnose carpal tunnel syndrome may vary among populations. The objective of this study was to determine the best cut-off point of median nerve cross-sectional area to diagnose carpal tunnel syndrome among Egyptian population and to compare the difference of median nerve cross-sectional area in diabetic patients versus healthy individuals.ResultsMean cross-sectional area was 7.78 ± 1.260 mm2 among healthy individuals and 8 ± 1.018 mm2 among diabetics. Cut-off cross-sectional area of median nerve above which compression is anticipated is 9.5 mm2.ConclusionUltrasound can be used to diagnose carpal tunnel syndrome by measuring the median nerve cross-sectional area.

Ultrasonographic and electrophysiological outcomes of carpal tunnel syndrome treated with low-level laser therapy: A double-blind, prospective, randomized, sham-controlled study.

Objectives The aim of this study was to investigate the therapeutic effects of low-level laser therapy (LLLT) on clinical, ultrasonographic (US), and electrophysiological findings in carpal tunnel syndrome (CTS).Patients and methods Between January 2015 and August 2015, 42 patients (7 males, 35 females; mean age: 50.4±8.7 years; range, 32 to 65 years) with mild-to-moderate CTS were randomly assigned to one of two groups: active LLLT (therapy group, n=22) 0.8 J/painful point and sham LLLT groups (n=20). Both groups wore neutral wrist orthoses. The patients were evaluated before and after 15 sessions of therapy (670 nm, 4 J/session over the carpal tunnel). Follow-up parameters included the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) Symptom Severity Scale (SSS), Functional Status Scale (FSS), nerve conduction studies and US evaluation of the median nerve cross-sectional area (CSA), vascularization (via power Doppler), flattening ratio (FR), and palmar bowing of the flexor retinaculum.Results Nocturnal paresthesia improved in both groups; however, pain and patients with a positive Phalen’s test reduced only in the therapy group (p=0.031). The FSS and SSS scores also improved only in the therapy group (p<0.001). Electrophysiologically, median sensory nerve conduction velocities showed a significant improvement only in the therapy group (p=0.002). The CSA, FR, and vascularization of the median nerve showed a significant improvement in the therapy group alone (p<0.001, p=0.048, and p=0.021, respectively).Conclusion Improvements in the signs and symptoms of CTS and hand function, the improvements in sensory nerve conduction studies, and reduction in median nerve CSA, FR and vascularity in the LLLT group can be attributed to the anti-inflammatory and analgesic effects of LLLT. This study provides new US data demonstrating efficacy of LLLT along with a clinical and electrophysiological improvement. The LLLT seems to be an easily applied, non-invasive treatment option.

Clinical, electrophysiological, and ultrasound evaluation for early detection of musculoskeletal hand disorders and nerve entrapment in mobile phone users

IntroductionSmartphone overuse may lead to musculoskeletal manifestations, such as carpal tunnel syndrome (CTS) and arthritis of hand joints, with an increased median nerve cross-sectional area (CSA). ObjectiveThe aim of this study is the early detection of musculoskeletal hand disorders using ultrasound techniques, and to detect nerve entrapment using clinical evaluation, ultrasound, and electrophysiological studies, in university employees younger than 35 years using mobile phones. Function is assessed using the Michigan Hand Outcomes Questionnaire (MHQ). Materials and methodsCross-sectional controlled study included 74 smartphone users classified into two groups according to a smartphone addiction scale (SAS), into high and low smart phone users, with 35 non-smartphone users with matched age and gender as a control group. A clinical assessment of nerve entrapment symptoms was performed, and the Michigan Hand Outcomes Questionnaire (MHQ), with a total score from 0 to100, was used to assess hand function. Electrodiagnostic studies of median and ulnar nerves were used to detect early nerve entrapment. Bilateral ultrasound was performed in order to assess the median nerve CSA and involvement of thumb and small hand joints. The data collected were analysed using the SPSS program version 20. ResultsCSAs of median nerves were significantly higher in the dominant hand of high smartphone users than in low and non-smartphone users (p<0.001). There was a significant positive correlation between CSA and SAS (r=0.45), visual analogue scale (VAS) (r=0.61), and duration of smartphone use (r=0.80), with negative correlation with MHQ (r=−0.63). Significant differences in were found in the electrophysiological studies of median and ulnar nerves. The mean ultrasound score for both hands was higher in the high smartphone users compared to low smartphone users (15.08±4.17 vs. 6.46±1.38, p<.001). ConclusionsThere is increased median nerve CSAs among high smartphone users associated with prolongation of both sensory and motor latencies and slow conduction velocities. Caution should be exercised when using mobile phones, in order to minimise the risk of developing hand musculoskeletal disorders.

Normative Values for the Sonographic Measurement of the Pediatric Median and Ulnar Nerves

Ultrasound investigation of peripheral nerves, long used in the adult population, has been shown to be of value in diagnosing a variety of peripheral nerve abnormalities. More recently, nerve sonography has also been shown to be of use in pediatrics. However, normative values for nerve size in children have been lacking. As such, the goal of this research was to establish normative data for cross sectional area (CSA) measurements of the median and ulnar nerves in children. The median and ulnar nerves of 48 children ranging in age from 2 years to 17 years were imaged by ultrasound. CSA measurements were made at 2 separate sites for each nerve and measured independently by 6 pediatric radiologists. Reliability of ultrasound measurements between the radiologists was assessed by calculating intraclass correlation coefficients. Linear mixed-effects modeling was performed to develop prediction models for nerve cross sectional area for each nerve segment; 95% prediction values were generated from these models to approximate normal ranges. Agreement in nerve cross-sectional area measurements among the 6 radiologists for all nerve segments was good (ICC 0.82, 95% CI 0.78 to 0.85). CSA for both the median and ulnar nerves is larger in older children. However, statistical models to predict CSA using height perform better rather than those using a child's age. The range of normal nerve segment CSA using these prediction models based on child height are reported. Median and ulnar nerve CSA can be reliably measured with ultrasound. Normal reference values for ulnar and median nerve CSA correlate with patient age but may be more optimally determined based on a child's height.

High-resolution ultrasound demonstrates in vivo effects of wrist movement on the median nerve along the forearm.

High-resolution ultrasound (HRUS) is the imaging method of choice to visualize peripheral nerve size, structure, and biomechanical performance. The purpose of this study was to show and quantify the effects of active and passive wrist alignment on median nerve (MN) cross-sectional area (CSA) along the forearm in a healthy population. Sixteen healthy volunteers underwent HRUS of their dominant forearm (n=16, 10 males, 6 females, 18-55 y of age). Median nerve's CSA was assessed at four defined areas on the forearm in relation to active and passive wrist alignment. Changes in wrist alignment were significantly associated with MN CSA (P < .001), regardless if the wrist was moved actively or passively. MN CSA was lowest during passive extension of the wrist joint and highest during passive flexion of the wrist joint (range: 4.5-23.2 mm2 ). The elasticity of nerve tissue, the loose connective tissue between the fascicles, and the paraneurium allow peripheral nerves to adapt to longitudinal strain. HRUS enables the demonstration of significant median nerve CSA changes along the forearm during active and passive wrist movement in healthy volunteers.

Dynamic Ultrasound Assessment of Median Nerve Mobility Changes Following Corticosteroid Injection and Carpal Tunnel Release in Patients With Carpal Tunnel Syndrome.

Decreased median nerve (MN) mobility was found in patients with carpal tunnel syndrome (CTS) and was inversely associated with symptom severity. It is unclear whether MN mobility can be restored with interventions. This study compared the changes in MN mobility and clinical outcomes after interventions. Forty-six patients with CTS received an injection (n = 23) or surgery (n = 23). Clinical outcomes [Visual Analogue Scale; Boston Carpal Tunnel Questionnaire (BCTQ), which includes the Symptom Severity Scale and Functional Status Scale; median nerve cross-sectional area; and dynamic ultrasound MN mobility parameters (amplitude, and R2 value and curvature of the fitted curves of MN transverse sliding)] were assessed at baseline and 12 weeks after the interventions. At baseline, the BCTQ-Functional Status Scale and median nerve cross-sectional area showed significant inter-treatment differences. At 12 weeks, both treatments had significant improvements in BCTQ-Symptom Severity Scale and Visual Analogue Scale scores and median nerve cross-sectional area, but with greater improvements in BCTQ-Functional Status Scale scores observed in those who received surgery than in those who received injections. MN mobility was insignificantly affected by both treatments. The additional application of dynamic ultrasound evaluation may help to discriminate the severity of CTS initially; however, its prognostic value to predict clinical outcomes after interventions in patients with CTS is limited.

Forensic Implications of Carpal Tunnel Syndrome in Relation to Neurological, Radiological and Orthopedic Assessments

Objective: To determine forensic implications of carpel tunnel syndrome in relation to neurological, radiological and orthopedic assessments. Study Design: Prospective Place and Duration of Study: Department of Forensic Medicine in collaboration with Radiology and Orthopaedic Departments, Govt. Khawaja Muhamamd Safdar Medical College Sialkot from 1st March 2020 to 28th February 2021. Methodology: One hundred and fifty patients of both genders were enrolled and age between 15-70 years. Details demographics age, sex and body mass index of all patients were recorded after taking written consent. Patients were divided into 2 groups. Group I had 75 patients with carpal tunnel syndrome and group II had 75 patients without carpal tunnel syndrome. Patients were undergone for ultrasonography and ultradiagnostic test used to diagnose the carpal tunnel syndrome. The carpal tunnel and proximal levels of the median nerve's CSA were measured, delta cross-sectional area (CSA) was determined for each wrist based on the differences between CSAc and CSAp. Sensitivity and specificity in wrists among both groups were identified. Results: There were 15 (20%) males and 60 (80%) females in group I with 90 wrists while in group II 17 (22.7%) males and 58 (77.3%) females in group II with 100 wrists. Mean age in group I was 49.68±9.66 years with mean BMI 26.47±9.54 kg/m2 and in group II mean age was 51.68±9.66 years with mean BMI 25.47±9.54 kg/m2. Mean CSAc in affected wrists group I was 17.11±6.44 greater than group II 08.17±6.58 mm2. Mean delta CSA in healthier wrists was lower 1.01±2.11 than group I 8.44±9.55 mm2. It was shown that the delta-CSA threshold of 2 mm2 had the maximum sensitivity (98.7%) and specificity (100%) in group I than control group. Conclusion: As compared to CSAc, the CSA is more accurate in diagnosing carpal tunnel syndrome. Keywords: Carpel tunnel syndrome (CTS), CSA, Wrists, Specificity, Sensitivity, Ultrasonography

Physiological Localization by Sensory and Motor Inching Studies and Structural Abnormalities Detected by Ultrasonographic Changes in Carpal Tunnel Syndrome

ObjectiveTo study mild to moderate carpal tunnel syndrome (CTS), compare median nerve entrapment sites detected by electrophysiological inching studies with ultrasonographic abnormalities of cross-sectional area (CSA), and correlate focal points of conduction delays detected by sensory and motor inching recorded from the third digit and second lumbrical muscle. DesignAnalytic cross-sectional study. SettingDepartment of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital, Bangkok, Thailand. ParticipantsHands from 10 participants without CTS (n=15) and hands with mild to moderate CTS from 29 participants (n=40) were selected by convenience sampling (N=55). InterventionsNot applicable. Main Outcome MeasuresCorrelation of electrophysiological entrapment site localization by inching study with anatomic entrapment site detected by ultrasound (US). ResultsIn all 40 hands tested, a sharply localized latency was found to increase across a 1-cm segment, most commonly 2-3 cm distal to the distal wrist crease for both sensory and motor studies, showing a good match between the 2 with Pearson correlation coefficient value (r=0.72). US revealed a narrowing CSA of the median nerve at 1-2 cm distal to the distal wrist crease. ConclusionsThis study showed a high correlation for focal point conduction delay detected by sensory and motor nerve conduction study. Recording from the second lumbricalis facilitated motor inching along the straight course of the nerve instead of the arcuate recurrent branch innervating the abductor pollicis brevis, the muscle traditionally used. US examination also revealed a localized narrowing of the median nerve CSA at 1-2 cm distal to the distal wrist crease, a possible site for anatomic entrapment. The most enlarged CSA was seen at the distal wrist crease, a level corresponding to the inlet of the carpal tunnel.

Influence of Smartphone Overuse on Grip Strength, Pinch Strength, and Cross-Sectional Area of Flexor Pollicis Longus Tendon and Median Nerve

AbstractBackground and Aim The adverse effects of smartphone size and weight on the hand and hand function have not been studied extensively. This study aimed to investigate the changes to the flexor pollicis longus tendon and median nerve using diagnostic ultrasound for high and low addiction smartphone users.Methodology In this cross-sectional study, 54 healthy male university students were divided into two groups according to the Smartphone Addiction Scale: high and low users. Demographic data, hand grip strength (kg), pinch strength (kg), and smartphone weight, length and width were measured and recorded. Diagnostic ultrasound examination determined the cross-sectional area of the median nerve (mm2) and flexor pollicis longus tendon (mm2) of the dominant and non-dominant hand.Result The cross-sectional area of the median nerve was significantly higher in the high-user group (7.4±1.3 mm2) than the low-user group (6.7±1.0 mm2). The correlation of phone weight, length and width with median nerve area was respectively positive, higher and significant (0.718, 0.747, and 0.733; p&lt;0.05). The flexor pollicis longus tendon in the mid-thenar region was moderately positively correlated with phone length (0.430; p&lt;0.02) for high addiction smartphone users.Conclusion The findings of the current study demonstrates that change to the median nerve and flexor pollicis longus tendon, could be linked to the width, weight and length of the smartphone and high addiction.

A model incorporating ultrasound to predict the probability of fast disease progression in amyotrophic lateral sclerosis

ObjectiveWe aimed to develop a model to predict amyotrophic lateral sclerosis (ALS) disease progression based on clinical and neuromuscular ultrasound (NMUS) parameters. MethodsALS patients were prospectively recruited. Muscle fasciculation (≥2 over 30-seconds, examined in biceps brachii-brachialis (BB), brachioradialis, tibialis anterior and vastus medialis) and nerve cross-sectional area (CSA) (median, ulnar, tibial, fibular nerve) were evaluated through NMUS. Ultrasound parameters were correlated with clinical data, including revised ALS Functional Rating Scale (ALSFRS-R) progression at one year. A predictive model was constructed to differentiate fast progressors (ALSFRS-R decline ≥ 1/month) from non-fast progressors. Results40 ALS patients were recruited. Three parameters emerged as strong predictors of fast progressors: (i) ALSFRS-R slope at time of NMUS (p = 0.041), (ii) BB fasciculation count (p = 0.027) and (iii) proximal to distal median nerve CSA ratio < 1.22 (p = 0.026). A predictive model (scores 0–5) was built with excellent discrimination (area under curve: 0.915). Using a score of ≥ 3, the model demonstrated good sensitivity (81.3%) and specificity (91.0%) in differentiating fast from non-fast progressors. ConclusionThe current model is simple and can predict the probability of fast disease progression. SignificanceThis model has potential as a surrogate biomarker of ALS disease progression.

Effect of Perineural Injection with Different Dextrose Volumes on Median Nerve Size, Elasticity and Mobility in Hands with Carpal Tunnel Syndrome.

This study aimed to investigate the effect of different injectate volumes on ultrasonographic parameters and the correlation to clinical outcomes under perineural dextrose injection (PDI). In this post hoc analysis of the randomized, double-blinded, three-arm trial, ultrasound-guided PDI with either 1 mL, 2 mL, and 4 mL 5% dextrose water was administered, respectively, in 14, 14, and 17 patients. Ultrasound outcomes included mobility, shear-wave elastography (SWE), and cross-sectional area (CSA) of the median nerve; clinical outcomes were Visual Analog Scale (VAS) and Boston Carpal Tunnel Questionnaire (BCTQ) score. Outcomes were measured before injection, and after injection at the 1st, 4th, 12th, and 24th week. For ultrasound outcomes, CSA decreased significantly from baseline data at all follow-up time-points in the 2 mL group (p = 0.005) and the 4 mL group (p = 0.015). The mean change of mobility from baseline showed a greater improvement on the 4 mL group than the other groups at the 1st week post-injection. For clinical outcomes, negative correlation between the VAS and mobility at the 1st (p = 0.046) and 4th week (p = 0.031) post-injection in the 4 mL group were observed. In conclusion, PDI with higher volume yielded better nerve mobility and decreased CSA of median nerve, but no changes of nerve elasticity.