Expert consensus on the combined investigation of carpal tunnel syndrome with electrodiagnostic tests and neuromuscular ultrasound.

Expert consensus was sought to guide clinicians on the use of electrodiagnostic tests (EDX) and neuromuscular ultrasound (NMUS) in the investigation of suspected carpal tunnel syndrome (CTS). Consensus was achieved using the Delphi method via three consecutive anonymised surveys of 15 experts and was defined as rating agreement ≥ 80%. The panel agreed that combining EDX and NMUS is more informative than using each modality alone. NMUS adds value in patients with clinically suspected CTS with non-localizing or normal EDX, atypical EDX, failed CTS surgery, polyneuropathy, and CTS suspected to be secondary to structural pathology. The median nerve cross-sectional area should be measured at the site of maximal nerve enlargement, and the nerve should be scanned from mid-forearm to the palm. The group also identified those situations where the wrist-to-forearm area ratio and longitudinal scans of the median nerve should also be obtained. EDX should always be performed to quantify CTS severity and in individuals over age 70. This document is an initial step to guide clinicians on the combined investigation of CTS using EDX and NMUS, to be updated regularly with the emergence of new research.

Utility of shear wave elastography and high-definition color for diagnosing carpal tunnel syndrome.

OBJECTIVE: The diagnostic values of measuring median nerve (MN) stiffness and vascularity with shear wave elastography (SWE) and high-definition (HD) color were investigated in carpal tunnel syndrome (CTS). METHODS: Seventy patients (123 wrists) with CTS and thirty-five healthy volunteers (70 wrists) were enrolled. Based on nerve conduction studies (NCS), the patients were subdivided into NCS-negative, mild-to-moderate, and severe CTS groups. MN and abductor pollicis brevis (APB) SWE and MN HD color were performed on a longitudinal plane. RESULTS: The mild-to-moderate and severe CTS groups showed increased MN stiffness at the wrist and MN stiffness ratio (wrist-to forearm) compared with the control (p < 0.001). The NCS-negative CTS group showed increased MN stiffness at the wrist (p = 0.022) and MN stiffness ratio (p = 0.032) compared with the control. The severe CTS group showed increased MN stiffness at the wrist compared with the mild-to-moderate CTS group (p = 0.034). The cutoff-values in diagnosing NCS-confirmed CTS were 50.12 kPa for MN stiffness at the wrist, 1.91 for MN stiffness ratio, and grade 1 for HD color. CONCLUSIONS: SWE and HD color are good supportive tools in diagnosing and assessing severity in CTS. SIGNIFICANCE: SWE and HD color demonstrated that MN in CTS was associated with increased stiffness and hypervascularity.

Prevalence and predictive factors for bilateral carpal tunnel syndrome by electrodiagnosis: A retrospective study.

INTRODUCTION: Carpal tunnel syndrome (CTS) is the most common compressive neuropathy. Patients who have unilateral symptoms are frequently found to have bilateral CTS by electrodiagnostic (EDx) study. We aimed to (a) study the prevalence and identify the predictive factors for bilateral CTS diagnosed by EDx; and (b) develop a model to predict bilateral CTS. METHODS: The retrospective clinical and EDx data of patients with CTS were collected and analyzed using the Chi-squared test and multiple logistic regression analysis. A model was fitted, and the best cutoff point determined. Calibration and discrimination performance of the model were performed. RESULTS: A total of 327 patients with a mean age of 50.0 years were enrolled. Most were women (82.6%), and the most common presenting symptom was hand numbness (93.6%). The median duration of symptoms was 60 days. The prevalence of bilateral CTS was 80.7%. In the multivariate analysis, the predictive factors for bilateral CTS were the presence of bilateral symptoms (AOR 6.7 [95%CI 3.1-14.3]), thenar muscle weakness (AOR 3.9 [95%CI 1.3-11.6]), and age ≥ 45 years (AOR 2.5 [95%CI 1.3-4.6]). The logistic regression model was fitted, and the best cutoff point determined. The area under the receiver operating curve (AUC) was 0.76. The respective optimism-corrected C index and Somers' D was 0.762 and 0.524. CONCLUSION: The prevalence of bilateral CTS was 80.7%. Our findings suggest bilateral CTS was predicted with adequate diagnostic accuracy by bilateral symptoms, age ≥ 45 years, and thenar muscle weakness.

Efficacy of 5% Dextrose Water Injection for Peripheral Entrapment Neuropathy: A Narrative Review.

Current non-surgical treatment for peripheral entrapment neuropathy is considered insignificant and unsustainable; thus, it is essential to find an alternative novel treatment. The technique of perineural injection therapy using 5% dextrose water has been progressively used to treat many peripheral entrapment neuropathies and has been proven to have outstanding effects in a few high-quality studies. Currently, the twentieth edition of Harrison's Principles of Internal Medicine textbook recommends this novel injection therapy as an alternative local treatment for carpal tunnel syndrome (CTS). Hence, this novel approach has become the mainstream method for treating CTS, and other studies have revealed its clinical benefit for other peripheral entrapment neuropathies. In this narrative review, we aimed to provide an insight into this treatment method and summarize the current studies on cases of peripheral entrapment neuropathy treated by this method.

Application of digital infrared thermography for carpal tunnel syndrome evaluation.

We investigated the thermographic findings of carpal tunnel syndrome (CTS). We enrolled 304 hands with electrodiagnostically identified CTS and 88 control hands. CTS hands were assigned to duration groups (D1, < 3 months; D2, 3‒6 months; D3, 6‒12 months; D4, ≥ 12 months) and severity groups (S1, very mild; S2, mild; S3, moderate; S4, severe). The temperature difference between the median and ulnar nerve territories (ΔM-U territories) decreased as CTS duration and severity increased. Significant differences in ΔM-U territories between the D1 and D3, D1 and D4, D2 and D4, and S1 and S4 groups (P = 0.003, 0.001, 0.001, and < 0.001, respectively) were observed. Thermal anisometry increased as CTS duration and severity increased. Significant differences in thermal anisometry between the D1 and D4 as well as the D2 and D4 groups (P = 0.005 and 0.04, respectively) were noted. Thermal anisometry was higher in the S4 group than in the S1, S2, and S3 groups (P = 0.009, < 0.001, and 0.003, respectively). As CTS progresses, skin temperature tends to decrease and thermal variation tends to increase in the median nerve-innervated area. Thermographic findings reflect the physiological changes of the entrapped median nerve.

Acute carpal tunnel syndrome: Clinical, electromyographic, and ultrasound features in 25 patients.

BACKGROUND: The acute presentation of carpal tunnel syndrome (CTS) is rare. When symptoms start acutely with no obvious causes, ultrasound (US) imaging may provide clues to the etiology. OBJECTIVE: This study describes the clinical, electromyographic, and US findings in 25 patients presenting with acute CTS (ACTS). METHODS: In this analysis, of the patients referred for electrodiagnostic confirmation of CTS over the past decade, 25 had an acute onset of symptoms. All patients underwent EMG/NCV and US of the median nerve at the carpal tunnel and forearm. RESULTS: Of the 25 cases with ACTS, 5 (20%) had bilateral involvement leading to the total hands studied to 30. In 14 (56%) patients, an inciting event was identified as a possible cause of ACTS. In 11 (44%) patients without an antecedent event, 7 (64%) had a persistent median artery (PMA) detected by US. Electrodiagnostic studies showed prolonged distal motor latency with normal motor conduction velocity proximal to the carpal tunnel in 24 (80%) of 30 hands, 6 (20%) hands showed absent compound muscle action potentials over the abductor pollicis brevis (APB), and 22 (73%) hands had absent sensory potentials. Denervation changes were seen in the APB in 13 (43%) hands, and motor unit potentials were absent in 6 (20%) hands. Sixteen (64%) patients underwent a carpal tunnel release for severe symptoms. CONCLUSION: CTS may present acutely without a clinically identifiable cause. US complements electrodiagnostic studies and is particularly useful when electrodiagnostic tests are non-diagnostic (due to absent compound muscle and sensory action potentials). US may also provide clues to the underlying cause.

The relationship of serum lipid profiles and obesity with the severity of carpal tunnel syndrome.

INTRODUCTION: Carpal tunnel syndrome (CTS) is a prominent compressive neuropathy. There are a number of risk factors for creating CTS but the effect of these factors on the severity of CTS is unclear. In this study, we aimed to assess the correlation of serum lipid profile and obesity with the severity of CTS. METHODS: this cross-sectional study was conducted on 118 patients with idiopathic CTS. Blood samples were obtained for determining the serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL-C), and high-density lipoprotein (HDL-C) after 12 hours of overnight fasting. The participants were then divided into two groups of normal and abnormal serum lipids. Body mass index ≥ 30 kg/m2 was considered as obesity. The severity of CTS was determined based on the electrophysiological results and Boston CTS Questionnaire (BCTSQ) that evaluates symptoms severity (SSS) and functional status (FSS) of patients. RESULTS: out of 118 participants, 108 patients performed lipid profile test that 41.17%, 50.42%, 25.21%, and 20.16% of them had TC ≥ 200, TG ≥ 150, LDL-C ≥ 130, and HDL-C < 60 milligrams per deciliter (mg/dl), respectively. The mean scores of SSS in patients with dyslipidemia including the high level of TC, TG, LDL-C, and low level of LDL-C were 34.59±7.86, 34.05±8.73, 34.93±8.21, and 33.48±7.56, respectively. There was no significant association between lipid profile and the symptom severity scale of CTS (p-value > 0.05). The mean BMI of participants was 31.35±5.35 kg/m2, and 58.5% of them had a BMI ≥ 30 kg/m2. The mean score of SSS and FSS was 33.18±8.24 and 24.43±7.12 in obese patients (BMI ≥ 30 kg/m2), and was 34.06±7.85 and 23.06±7.67 in patients with BMI < 30 kg/m2. We found no significant association between obesity with the SSS and FSS (p-value = 0.53 and 0.32, respectively). In terms of the relationship between electrophysiological grading with obesity, 44 (63.8%) of patients with BMI ≥ 30 kg/m2 and 22 (45.8%) patients with BMI < 30 kg/m2 had severe to extreme severe CTS. There was no significant association between obesity and the severity of CTS (p-value = 0.054). CONCLUSION: the results of this study did not demonstrate an association between serum lipid profile and obesity with the severity of carpal tunnel syndrome. The findings of this study may not be extrapolated to other populations. Further studies with more samples are needed to investigate this association.

Structural white matter alterations in carpal tunnel syndrome: A modified TBSS study.

Functional and structural brain alterations have been noted in carpal tunnel syndrome (CTS), the most common entrapment peripheral neuropathy. Previous studies were mainly focused on somatosensory cortices. However, the changes of white matter diffusion properties in nonsensorimotor cortices remain uninvestigated. We utilized a modified tract-based spatial statistics (TBSS) pipeline to explore CTS-related white matter plasticity, omitting the skeletonization step and registering diffusion tensor imaging (DTI) data to a study-specific, high resolution T1 template by an optimized registration method. The modified TBSS was demonstrated to be more sensitive to detect changes in white matter integrity than the standard TBSS approach. In this study, 25 moderate/severe CTS patients and 17 age- and sex-matched healthy controls (HC) were evaluated with DTI. Fractional anisotropy (FA) and radial diffusivity (RD) were calculated for group comparison. And the relationship between diffusion parameters and clinical assessments was also analyzed. Comparing with the healthy controls, CTS patients showed significantly increased FA and decreased RD in areas of multisensory integration and motor control involving the central opercular cortex and supplementary motor area (SMA) of the dominant hemisphere. Moreover, altered diffusion parameters in the central opercular cortex of the dominant hemisphere were significantly correlated with Boston Carpal Tunnel Questionnaire (BCTQ) scores. It is considered to be a form of maladaptive neuroplastic response to CTS-associated afference and motor control deficits. Such insight may be helpful in developing new strategies for the treatment of CTS.

Automated Segmentation of the Median Nerve in the Carpal Tunnel using U-Net.

Nerve area and motion in carpal tunnel syndrome (CTS) are currently under investigation in terms of prognostic potential. Therefore, there is increasing interest in non-invasive measurement of the nerve using ultrasound. Manual segmentation is time consuming and subject to inter-rater variation, providing an opportunity for automation. Dynamic ultrasound images (n = 5560) of carpal tunnels from 99 clinically diagnosed CTS patients were used to train a U-Net-shaped neural network. The best results from the U-Net were achieved with a location primer as initial region of interest for the segmentations during finger flexion (Dice coefficient = 0.88). This is comparable to the manual Dice measure of 0.92 and higher than the resulting automated Dice measure of wrist flexion (0.81). Although there is a dependency on image quality, a trained U-Net can reliably be used in the assessment of ultrasound-acquired median nerve size and mobility, considerably decreasing manual effort.

Diabetic polyneuropathy and carpal tunnel syndrome together affect hand strength, tactile sensation and dexterity in diabetes patients.

AIMS/INTRODUCTION: Carpal tunnel syndrome (CTS) and diabetic polyneuropathy (DPN) can occur together, and this concomitance is thought to be higher in diabetes patients. We aimed to examine and compare hand function in type 2 diabetes mellitus patients without CTS and DPN (CTS-DPN-), patients with CTS without DPN (CTS+DPN-), patients with DPN without CTS (CTS-DPN+), and patients with CTS and DPN (CTS+DPN+). MATERIALS AND METHODS: A total of 161 type 2 diabetes mellitus patients underwent physical examination and electrodiagnostic tests. Grip and pinch strengths, tactile sensory thresholds were measured for each participant. Purdue pegboard test was used in evaluating the hand dexterity of the participants. RESULTS: Of the 161 type 2 diabetes mellitus participants, 36 (22.4%) had both CTS and DPN. CTS participants had lower grip (26.6 ± 10.6 vs 35.2 ± 14.3, P < 0.001) and pinch (6.3 ± 2.6 vs 7.5 ± 2.9, P = 0.026) strengths compared with non-CTS participants, whereas DPN participants had elevated tactile sensory thresholds of both the second (2.8 [2.8-3.6] vs 2.4 [2.4-2.8], P < 0.001) and the fifth (2.8 [2.8-3.6] vs 2.4 [2.4-2.8], P < 0.001) fingers compared with non-DPN participants. The CTS+DPN+ group had lower Purdue pegboard test scores than other groups. Grip (r = 0.482, 0.530, 0.467, 0.498, all P < 0.001) and pinch (r = 0.246, P = 0.003; r = 0.265, P = 0.001; r = 0.264, P = 0.001; r = 0.235, P = 0.005) strengths were positively correlated with Purdue pegboard test scores, whereas tactile sensory thresholds were negatively correlated with Purdue pegboard test scores (r = -0.447 to -0.359, all P < 0.001). CONCLUSION: Type 2 diabetes mellitus patients with both DPN and CTS had lower grip and pinch strengths and decreased tactile sensation, both of which were correlated with poorer hand dexterity.

Pathogenic Hydrogel? A Novel-Entrapment Neuropathy Model Induced by Ultrasound-Guided Perineural Injections.

Entrapment neuropathy (EN) is a prevalent and debilitative condition caused by a complex pathogenesis that involves a chronic compression-edema-ischemia cascade and perineural adhesion that results in excessive shear stress during motion. Despite decades of research, an easily accessible and surgery-free animal model mimicking the mixed etiology is currently lacking, thus limiting our understanding of the disease and the development of effective therapies. In this proof-of-concept study, we used ultrasound-guided perineural injection of a methoxy poly(ethylene glycol)-b-Poly(lactide-co-glycoilide) carboxylic acid (mPEG-PLGA-BOX) hydrogel near the rat's sciatic nerve to induce EN, as confirmed sonographically, electrophysiologically, and histologically. The nerve that was injected with hydrogel appeared unevenly contoured and swollen proximally with slowed nerve conduction velocities across the injected segments, thus showing the compressive features of EN. Histology showed perineural cellular infiltration, deposition of irregular collagen fibers, and a possible early demyelination process, thus indicating the existence of adhesions. The novel method provides a surgery-free and cost-effective way to establish a small-animal model of EN that has mixed compression and adhesion features, thus facilitating the additional elucidation of the pathophysiology of EN and the search for promising treatments.

Median nerve swelling is an independent risk factor of carpal tunnel syndrome in chronic hemodialysis patients.

Carpal tunnel syndrome (CTS) has a wide variety of underlying causes and occurs in association with dialysis. Early diagnosis is essential to prevent permanent nerve damage and functional sequelae. We evaluated the association between CTS and cross-sectional area (CSA) of the median nerve in chronic hemodialysis (HD) patients. Patients with end-stage renal disease on maintenance HD via arteriovenous fistula were enrolled. We divided 43 patients into two groups; patients diagnosed with CTS (n = 19) and patients without CTS (n = 24). The median nerve CSA was measured at the wrist (CSA-W) and forearm (CSA-F) by ultrasonography. Median nerve swelling was assessed by the wrist-to-forearm ratio (WFR). There were no significant differences in the underlying causes of chronic kidney disease and adequacy of dialysis between the two groups (p = NS). The patients with CTS showed significantly higher WFR than the patients without CTS (p = 0.001). Univariate Cox regression analysis revealed that WFR >1.25 (odds ratio, 6.30; 95% confidence interval, 1.44-27.45; p = 0.014) was associated with CTS in HD patients. The factors traditionally associated with CTS such as age, sex, diabetes, vintage of HD, ß2-MG, intact PTH, and Kt/V were not associated with CTS. After adjustment for age and sex, we found a strong correlation between CTS and the WFR >1.25 (odds ratio, 10.8; 95% confidence interval, 1.85-62.4; p = 0.008). High WFR was associated with the development of CTS, and median nerve swelling was an independent risk factor of CTS in chronic HD patients.

Prolonged median distal sensory nerve action potential duration in carpal tunnel syndrome.

OBJECTIVE: Routine nerve conduction study (NCS) parameters are less sensitive in the early stage of carpal tunnel syndrome (CTS). Recently, some studies have shown that prolonged distal sensory nerve action potential (DSNAP) duration may be a more sensitive technique for the diagnosis of demyelinating peripheral neuropathies. We aimed to evaluate the sensitivity of median DSNAP duration in patients with CTS. METHODS: DSNAP duration and routine NCS data of the median nerve were retrospectively collected in 173 CTS patients, 73 controls, and 78 cervical radiculopathy patients. RESULTS: Prolonged median DSNAP durations were found in 22 patients (22/35, 63%) and 36 patients (36/54, 67%) in the minimal and mild CTS groups respectively, which was more sensitive than routine NCS parameters. The percentage of patients demonstrating abnormalities in median NCS was significantly increased from 80% to 92% with the addition of DSNAP duration. CONCLUSION: Our results demonstrate the electrodiagnostic value of median DSNAP duration for the diagnosis of CTS, especially in early cases.

Socioeconomic factors predicting outcome in surgically treated carpal tunnel syndrome: a national registry-based study.

The study aimed to investigate socioeconomic factors in patients with carpal tunnel syndrome (CTS) and to evaluate their impact on outcome following open carpal tunnel release (OCTR). Data from the National Quality Register for Hand Surgery were combined with socioeconomic data (marital status, education level, earnings, migrant status, occupation, sick leave, unemployment, and social assistance) from Statistics Sweden to evaluate OCTRs performed from 2010 to 2016 (total 10,746 OCTRs). Patients completed QuickDASH (short version of Disabilities of Arm, Shoulder and Hand) questionnaires preoperatively (n = 3597) and at three (n = 2824) and 12 months (n = 2037) postoperatively. The effect of socioeconomic factors on QuickDASH scores was analyzed with linear regression analysis. Socioeconomically deprived patients scored higher on the QuickDASH on all occasions than patients with higher socioeconomic status. Being widowed, having a low education level, low earnings, immigrant status, frequent sick leave and dependence on social assistance all increased the postoperative QuickDASH score at 12 months. The change in total score for QuickDASH between preoperative and 12 months postoperatively did not vary between the groups. We conclude that such factors as being widowed, having a lower education level, low earnings, immigrant status, frequent sick leave and social assistance dependence are associated with more symptoms both before and after OCTR for CTS, but these factors do not affect the relative improvement in QuickDASH.

Is it time to revisit the Boston Carpal Tunnel Questionnaire? New insights from a Rasch model analysis.

BACKGROUND: The Boston Carpal Tunnel Questionnaire (BCTQ) is a patient-reported outcome measure (PROM) used to measure symptom severity and function in carpal tunnel syndrome (CTS). Despite its wide use, investigation of its measurement properties using modern psychometric methodologies is limited. METHODS: Completed BCTQ data collected routinely in the Canterbury carpal tunnel clinic was used to investigate the structural validity and measurement properties of the BCTQ through application of a Rasch model analytic approach. RESULTS: A total of 600 patients with electrodiagnostically confirmed CTS in their right hand were randomly selected from the database and analyzed. Mean age was 48.8 y, and 73% were women. Initial analysis showed that the 19 items could not be reliably added up to form a single linear construct. All subsequent analyses were done by subscale only. The Symptom Severity Subscale (SSS) displayed a large amount of local dependence. This could be accommodated through the creation of four clinically derived testlets, allowing for the ordinal SSS raw score to be transformed to a linear measure. The Functional Status Subscale (FSS) displayed a number of issues regarding its psychometric integrity. These include scale and item fit, targeting, differential item functioning, and dimensionality. CONCLUSIONS: This study shows that a single total score generated across all BCTQ items is not psychometrically valid, and that the SSS and FSS subscales should be treated separately. We propose a modified scoring system for the SSS, resulting in a linear measure that can be used in the analysis of future and existing datasets.

Initial findings in traumatic peripheral nerve injury and repair with diffusion tensor imaging.

OBJECTIVE: Management of peripheral nerve injuries requires physicians to rely on qualitative measures from patient history, electromyography, and physical exam. Determining a successful nerve repair can take months to years for proximal injuries, and the resulting delays in clinical decision-making can lead to a negative impact on patient outcomes. Early identification of a failed nerve repair could prevent permanent muscle atrophy and loss of function. This study aims to test the feasibility of performing diffusion tensor imaging (DTI) to evaluate injury and recovery following repair of wrist trauma. We hypothesize that DTI provides a noninvasive and reliable assessment of regeneration, which may improve clinical decision-making and alter the clinical course of surgical interventions. METHODS: Clinical and MRI measurements from subjects with traumatic peripheral nerve injury, carpal tunnel syndrome, and healthy control subjects were compared to evaluate the relationship between DTI metrics and injury severity. RESULTS: Fractional anisotropy from DTI was sensitive to differences between damaged and healthy nerves, damaged and compressed nerves, and injured and healthy contralateral nerves. Longitudinal measurements in two injury subjects also related to clinical outcomes. Implications of other diffusion measures are also discussed. INTERPRETATION: DTI is a sensitive tool for wrist nerve injuries and can be utilized for monitoring nerve recovery. Across three subjects with nerve injuries, this study has shown how DTI can detect abnormalities between injured and healthy nerves, measure recovery, and determine if re-operation was successful. Additional comparisons to carpal tunnel syndrome and healthy nerves show that DTI is sensitive to the degree of impairment.

Ultrasound examination predicts 6-month progression in carpal tunnel syndrome patients.

Carpal tunnel syndrome (CTS) is a peripheral neuropathy resulting from chronic median nerve compression. Chronic compression leads to neurological changes that are quantified through nerve conduction studies (NCS). Although NCS represents the gold standard in CTS assessment, they provide limited prognostic value. Several studies have identified ultrasound as a tool in diagnosing and potentially predicting the progression of CTS in patients. The purpose of this study was to evaluate the predictive value of ultrasound examination in CTS patients. Twenty patients recruited at their first visit with the neurologist completed two NCS and ultrasound examinations approximately 6 months apart. Ultrasound examination consisted of B-mode, pulse-wave Doppler and colour Doppler ultrasound videos and images to quantify median nerve cross-sectional area, intraneural blood flow velocity in three wrist postures (15° flexion, neutral, and 30° extension), and displacement of the flexor digitorum superficialis (FDS) tendon and the adjacent subsynovial connective tissue (SSCT) of the middle finger during repetitive finger flexion-extension cycles. A questionnaire was administered to assess the work-relatedness of CTS. Linear regression analyses revealed that intraneural blood flow velocity (R2 = 0.36, p = .03), assessed in wrist flexion, and relative FDS-SSCT displacement (R2 = 0.27, p = .04) and shear strain index (R2 = 0.28, p = .04) were significant predictors of nerve sensory and motor changes at 6 months. Results suggest the possibility of using a battery of ultrasound measures as viable markers to predict median nerve functional changes within 6 months.

Neuromuscular ultrasound findings in carpal tunnel syndrome with symptoms mainly in the nondominant hand.

BACKGROUND: Carpal tunnel syndrome (CTS) may be associated with structural lesions or anatomical variations at the wrist, especially in patients whose symptoms are more severe in, or limited to, the nondominant hand. The aims of this study were to identify the type and frequency of structural abnormalities and anatomical variations, and to demonstrate the contribution of ultrasound in this subgroup of CTS patients. METHODS: A retrospective chart review was performed on all patients referred to the electromyography laboratory who fulfilled the diagnostic criteria for CTS and who underwent neuromuscular ultrasound. RESULTS: Of 114 CTS patients with symptoms mainly in nondominant hand, 51 (44.7%) had structural abnormalities or anatomical variations detected by ultrasound. In multivariable analysis, symptoms mainly in the nondominant hand and a body mass index (BMI) <30 kg/m2 were the only independent variables significantly associated with structural findings, odds ratios 2.3 (P < .001) and 1.9 (P = .006), respectively. CONCLUSIONS: Neuromuscular ultrasound, in addition to electrodiagnostic studies, should be considered in all CTS patients with symptoms more severe in nondominant hand as a significant number have abnormal structural abnormalities or anatomical variations that may be causative or change the therapeutic approach.

Effects of Diacutaneous Fibrolysis on Mechanosensitivity, Disability, and Nerve Conduction Studies in Mild to Moderate Carpal Tunnel Syndrome: Secondary Analysis of a Randomized Controlled Trial.

OBJECTIVE: People diagnosed with carpal tunnel syndrome (CTS) have fibrosis between the soft, connective, and neural tissues that could worsen the compression of the median nerve. The diacutaneous fibrolysis (DF) technique may release tissue adhesions and increase the mobility of connective tissues. The purpose of this study was to compare the outcomes of DF in people with mild to moderate CTS on mechanosensitivity, disability, and nerve conduction studies. METHODS: This was a secondary analysis of a double-blinded, randomized, placebo-controlled trial. Patients were recruited between April and September 2016 from the Department of Neurophysiology at the Hospital Miguel Servet, Zaragoza, Spain. Thirty-nine people (52 wrists) diagnosed with mild to moderate CTS were included. Participants were randomly assigned to either the DF group (n = 26) or the sham group (n = 26). Both groups received 5 therapy sessions, 2 sessions per week. Mechanosensitivity with the Upper Limb Neurodynamic Test 1, symptom severity and functional status with the Boston Carpal Tunnel Questionnaire, and median nerve sensory conduction velocity with nerve conduction studies were the outcomes measured. Assessments were recorded at baseline and after the intervention. RESULTS: The DF group showed significant improvements in the following: mechanosensitivity, with 28.46 degrees of elbow extension range of motion (95% CI = 19.2-37.7); an increase of 1.0 point (95% CI = 0.7-1.4) for the Boston Carpal Tunnel Questionnaire symptom severity and functional status score; and sensory conduction velocity of median nerve, which improved to 5.8 m/s (95% CI = 2.5-9.2). CONCLUSION: Participants with mild to moderate CTS experienced improvements in symptom severity, functional status, mechanosensitivity, and nerve conduction studies after 5 sessions of DF. IMPACT: This study provides evidence of an approach based on soft and connective tissues around the median nerve in patients with CTS.