Consensus criteria for the classification of carpal tunnel syndrome in epidemiologic studies

Electrodiagnostic studies and new diagnostic modalities for evaluation of peripheral nerve disorders

Electrodiagnostic studies (EDx) are frequently performed in the diagnostic evaluation of peripheral nerve disorders. There is increasing interest in the use of newer, alternative diagnostic modalities, in particular imaging, either to complement or replace established EDx protocols. However, the evidence to support this approach has not been expansively reviewed. In this paper, diagnostic performance data from studies of EDx and other diagnostic modalities in common peripheral nerve disorders have been analyzed and described, with a focus on radiculopathy, plexopathy, compressive neuropathies, and the important neuropathy subtypes of Guillain-Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), vasculitic neuropathy and diabetic neuropathy. Overall EDx retains its place as a primary diagnostic modality in the evaluated peripheral nerve disorders. Magnetic resonance imaging and ultrasound have developed important complementary diagnostic roles in compressive and traumatic neuropathies and atypical CIDP, but their value is more limited in other neuropathy subtypes. Identification of hourglass constriction in nerves of patients with neuralgic amyotrophy may have therapeutic implications. Investigation of radiculopathy is confounded by poor correlation between clinical features and imaging findings and the lack of a diagnostic gold standard. There is a need to enhance the literature on the utility of these newer diagnostic modalities.

Mapping Neurophysiological Patterns in Carpal Tunnel Syndrome: Correlations With Tinel's and Phalen's Signs

Background This study aimed to observe the neurophysiological severity grading of carpel tunnel syndrome (CTS) using nerve conduction studies (NCSs) and the correlation between Tinel's and Phalen's signs. Methodology In this cross-sectional study, 240 patients of CTS were enrolled. NCSs were conducted in 480 hands. Various variables such as distal latency, amplitude, and nerve conduction velocity in both sensory and motor median nerves were recorded. The provocative tests capable of reproducing patients' symptoms such as Phalen's test and Tinel's test were performed on all 480 hands studied. Results Neurophysiological variables were affected in 449 out of 480 hands. Tinel's sign was observed in 59% of cases (265 hands) while Phalen's sign was positive in 37.2% (167 hands) of cases. Severity grading of CTS based on neurophysiological variables resulted in Grade I (mild) in 202 hands, Grade II (mild to moderate) in 56 hands, Grade III (moderate) in 39 hands, and Grade IV (severe) in 152 hands. Provocative tests (Tinel's and Phalen's) used for the diagnosis of CTS were positive in 68 hands (36.66%) and 26 hands (12.8%), respectively, in mild Grade I. However, as the CTS severity grade increased, the provocative test success rate also increased simultaneously. In severe Grade IV CTS, Tinel's and Phalen's tests were positive in 134 (88.1%) hands and 94 (61.8%) hands, respectively. Conclusions This study underscores the unreliability of Tinel's and Phalen's signs as screening methods for CTS severity. With moderate sensitivity and specificity, NCSs are deemed essential for confirming CTS diagnosis and assessing severity, especially in mild cases that might be mistakenly perceived as normal hands by consultants.

Local corticosteroid injection versus physical therapy for the treatment of carpal tunnel syndrome: A systematic review and meta-analysis of randomized controlled trials

The comparative effect of commonly used conservative treatments for carpal tunnel syndrome remained controversial. The purpose of this study was to compare the clinical effect of local corticosteroid injection and physical therapy for the treatment of carpal tunnel syndrome. A systematic literature search of PubMed, EMBASE, and Cochrane library was conducted to identify relevant randomized clinical trials published before 21st Mar 2023. Two independent reviewers assayed quality of included studies using the Cochrane collaboration risk of bias tool. Relevant data were extracted and pooled analyses were conducted. Outcome measurements included Boston Carpal Tunnel Syndrome Questionnaire, visual analogue scale and some electrophysiology tests, while the former two were set as the primary outcomes. Subgroup analysis and sensitive analysis were performed and publication bias was evaluated. Heterogeneity among the included studies was examined using the I2 statistic. After selection, 12 studies were identified eligibility for inclusion. Only one study was found to have a high risk of bias. Pooled data of primary outcomes did not show any differences between treatments, and subgroup analysis supported the results. However, patients treated with local corticosteroid injection showed better improvement in distal motor latency (p = 0.002) and compound muscle action potential (p = 0.04). Some studies failed to pass the sensitive analysis, indicating the related analysis might be not so stable. A slight publication bias was observed in subgroup analysis of function scales, among three publication bias test. In conclusion, compared to physical therapy, local corticosteroid injection might have better treatment effects on carpal tunnel syndrome.

Carpal tunnel syndrome

Median neuropathy at the wrist, commonly referred to as carpal tunnel syndrome (CTS), is the most common entrapment neuropathy. It is caused by chronic compression of the median nerve at the wrist within the space-limited carpal tunnel. Risk factors that contribute to the etiology of compression include female gender, obesity, work-related factors, and underlying medical conditions, such as hypothyroidism, pregnancy, and amyloidosis. The diagnosis is made on clinical grounds, although these can be confounded by anatomical variations. Electrodiagnostic studies, which are specific and sensitive in diagnosing CTS, support the diagnosis; however, a subgroup may present with normal results. The advent of imaging techniques, including ultrasound and MRI, further assists the diagnostic process. The management of CTS is divided into the nonsurgical approaches that include hand therapy, splinting and corticosteroid injection, and surgical decompression of the carpal tunnel. Although several surgical techniques have been developed, no one method is more effective than the other. Each of these management approaches are effective at providing symptom relief and are utilized at different severities of the condition. There is, however, a lack of consensus on standardized diagnostic criteria, as well as when and to whom to refer patients for surgery.

The sensitivity of median versus ulnar palmar mixed nerve study in the early diagnosis of carpal tunnel syndrome

Background

Electrodiagnostic tests (EDX) are the most frequent and applicable studies in early diagnosis of carpal tunnel syndrome (CTS), but the definitive sensitive and specific tests are still under study. We aimed to evaluate the role of the median versus ulnar palmar mixed nerve study (Mix M-U), and its sensitivity in comparison to other provocative comparison studies, in supporting the early diagnosis of CTS. This cross-sectional study included 142 idiopathic early CTS hands from 100 patients and 71 hands from 50 healthy subjects as a control group. We did routine median motor and sensory studies and 4 comparative tests namely median versus radial sensory study (MVR), Mix M-U, median versus ulnar sensory study (MVU), and median versus ulnar lumbrical-interossei motor study (LU-IN).

Results

The routine median motor and sensory latency and amplitude showed a statistically significant difference between CTS and control groups as (p< 0.05) and a highly statistically significant difference between the 2 groups as regards the 4 comparative tests as (p< 0.0001). The specificities of all the 4 comparative tests were higher than 90%. MVR test had the highest sensitivity (92.2%) and followed by Mix M-U study (82.2%) and MVU (78.7%), and the least sensitive test was the LM-IN (66.9%).

Conclusions

Although the patients’ results fall within the normal range according to the reference range in the literature, it showed a statistically significant difference when compared to controls. A high percentage of those symptomatic patients showed results of typical CTS when tested with the comparative studies so there is a need to use these sensitive tests to diagnose cases with early CTS. According to sensitivity studies, the selection of which tests to do in order is a challenging choice. For the diagnosis of cases with early CTS with a normal ordinary motor and sensory studies, MVR comparative technique appeared as the best sensitive and specific provocative electrophysiological test followed by the Mix M-U test. We recommend the use of a combination of both tests first in the diagnosis of early CTS and if one of them was negative we can use the other comparative studies MVU and then LM-IN studies.

Local corticosteroid injection versus placebo for carpal tunnel syndrome

BACKGROUND

Carpal tunnel syndrome (CTS) is a very common clinical syndrome manifested by signs and symptoms of irritation of the median nerve at the carpal tunnel in the wrist. Direct and indirect costs of CTS are substantial, with estimated costs of two billion US dollars for CTS surgery in the USA in 1995 alone. Local corticosteroid injection has been used as a non-surgical treatment for CTS many years, but its effectiveness is still debated.

OBJECTIVES

To evaluate the benefits and harms of corticosteroids injected in or around the carpal tunnel for the treatment of carpal tunnel syndrome compared to no treatment or a placebo injection.

SEARCH METHODS

We used standard, extensive Cochrane search Methods. The searches were 7 June 2020 and 26 May 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-randomised trials of adults with CTS that included at least one comparison group of local injection of corticosteroid (LCI) into the wrist and one group that received a placebo or no treatment.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcome was 1. improvement in symptoms at up to three months of follow-up. Our secondary outcomes were 2. functional improvement, 3. improvement in symptoms at greater than three months of follow-up, 4. improvement in neurophysiological parameters, 5. improvement in imaging parameters, 6. requirement for carpal tunnel surgery, 7. improvement in quality of life and 8.

ADVERSE EVENTS

We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We included 14 trials with 994 participants/hands with CTS. Only nine studies (639 participants/hands) had useable data quantitatively and in general, these studies were at low risk of bias except for one quite high-risk study. The trials were conducted in hospital-based clinics across North America, Europe, Asia and the Middle East. All trials used participant-reported outcome measures for symptoms, function and quality of life. There is probably an improvement in symptoms measured at up to three months of follow-up favouring LCI (standardised mean difference (SMD) -0.77, 95% confidence interval (CI) -0.94 to -0.59; 8 RCTs, 579 participants; moderate-certainty evidence). Up to six months this was still evident favouring LCI (SMD -0.58, 95% CI -0.89 to -0.28; 4 RCTs, 234 participants/hands; moderate-certainty evidence). There is probably an improvement in function measured at up to three months favouring LCI (SMD -0.62, 95% CI -0.87 to -0.38; 7 RCTs, 499 participants; moderate-certainty evidence). We are uncertain if there is a difference in median nerve DML at up to three months of follow-up (mean difference (MD) -0.37 ms, 95% CI -0.75 to 0.02; 6 RCTs, 359 participants/hands; very low-certainty evidence). The requirement for surgery probably reduces slightly in the LCI group at one year (risk ratio 0.84, 95% CI 0.72 to 0.98; 1 RCT, 111 participants, moderate-certainty evidence). Quality of life, measured at up to three months of follow-up using the Short-Form 6 Dimensions questionnaire (scale from 0.29 to 1.0; higher is better) probably improved slightly in the LCI group (MD 0.07, 95% CI 0.02 to 0.12; 1 RCT, 111 participants; moderate-certainty evidence). Adverse events were uncommon (low-certainty evidence). One study reported 2/364 injections resulted in severe pain which resolved over "several weeks" and 1/364 injections caused a "sympathetic reaction" with a cool, pale hand that completely resolved in 20 minutes. One study (111 participants) reported no serious adverse events, but 65% of LCI-injected and 16% of the placebo-injected participants experienced mild-to-moderate pain lasting less than two weeks. About 9% of participants experienced localised swelling lasting less than two weeks. Four studies (229 participants) reported that they experienced no adverse events in their studies. Three studies (220 participants) did not specifically report adverse events.

AUTHORS' CONCLUSIONS

Local corticosteroid injection is effective for the treatment of mild and moderate CTS with benefits lasting up to six months and a reduced need for surgery up to 12 months. Where serious adverse events were reported, they were rare.

Revision Carpal Tunnel Release With Umbilical Cord Allograft: A Four-Year Retrospective Cohort Study

Background: Refractory symptoms of carpal tunnel syndrome can persist or reoccur after carpal tunnel release (CTR) surgery in 1% to 25% of patients, with up to 12% of patients requiring secondary surgery. If revision surgery is required, the results are much less successful compared to primary surgery. In this study, we investigated whether cryopreserved human umbilical cord allograft placement during CTR revision surgery improved short- and long-term surgical outcomes. Methods: We conducted a single-center cohort analysis of patients between January 2015 and July 2018 who underwent secondary open revision CTR with umbilical cord allograft for recurrent or persistent compression neuropathy of the median nerve. Surgical outcomes of patients in the study group-reduction of pain, paresthesia, and weakness; complications; and Disabilities of the Arm, Shoulder and Hand (QuickDASH) scores-were compared to the outcomes of controls without umbilical cord allograft use who were operated on by the same surgeon between December 2011 and September 2015. Results: A total of 37 patients underwent CTR with (n=26) and without (n=11) umbilical cord allograft (mean follow-up of 4 years). Following surgery, preoperative symptoms of pain (96% vs 73%, P=0.048) and paresthesia (100% vs 73%, P=0.014) were significantly improved in the patients who received umbilical cord allograft. Mean QuickDASH scores (19.0 vs 23.7, P=0.58) and preoperative weakness (90% vs 67%, P=0.14) were improved in the patients who received umbilical cord allograft but were nonsignificant. Short- and long-term complications were similar between groups (P=0.56, P=0.51, respectively). Conclusion: This study suggests that human umbilical cord allograft placement during open revision CTR is safe and effective for improving long-term symptoms of compressive neuropathy in patients with recurrent carpal tunnel syndrome.

The quality of occupational healthcare for carpal tunnel syndrome, healthcare expenditures, and disability outcomes: A prospective observational study

INTRODUCTION/AIMS

In prior work, higher quality care for work-associated carpal tunnel syndrome (CTS) was associated with improved symptoms, functional status, and overall health. We sought to examine whether quality of care is associated with healthcare expenditures or disability.

METHODS

Among 343 adults with workers' compensation claims for CTS, we created patient-level aggregate quality scores for underuse (not receiving highly beneficial care) and overuse (receiving care for which risks exceed benefits). We assessed whether each aggregate quality score (0%-100%, 100% = better care) was associated with healthcare expenditures (18-mo expenditures, any anticipated need for future expenditures) or disability (days on temporary disability, permanent impairment rating at 18 mo).

RESULTS

Mean aggregate quality scores were 77.8% (standard deviation [SD] 16.5%) for underuse and 89.2% (SD 11.0%) for overuse. An underuse score of 100% was associated with higher risk-adjusted 18-mo expenditures ($3672; 95% confidence interval [CI] $324 to $7021) but not with future expenditures (-0.07 percentage points; 95% CI -0.48 to 0.34), relative to a score of 0%. An overuse score of 100% was associated with lower 18-mo expenditures (-$4549, 95% CI -$8792 to -$306) and a modestly lower likelihood of future expenditures (-0.62 percentage points, 95% CI -1.23 to -0.02). Quality of care was not associated with disability.

DISCUSSION

Improving quality of care could increase or lower short-term healthcare expenditures, depending on how often care is currently underused or overused. Future research is needed on quality of care in varied workers' compensation contexts, as well as effective and economical strategies for improving quality.

Application of an Improved U2-Net Model in Ultrasound Median Neural Image Segmentation

To investigate whether an improved U2-Net model could be used to segment the median nerve and improve segmentation performance, we performed a retrospective study with 402 nerve images from patients who visited Huashan Hospital from October 2018 to July 2020; 249 images were from patients with carpal tunnel syndrome, and 153 were from healthy volunteers. From these, 320 cases were selected as training sets, and 82 cases were selected as test sets. The improved U2-Net model was used to segment each image. Dice coefficients (Dice), pixel accuracy (PA), mean intersection over union (MIoU) and average Hausdorff distance (AVD) were used to evaluate segmentation performance. Results revealed that the Dice, MIoU, PA and AVD values of our improved U2-Net were 72.85%, 79.66%, 95.92% and 51.37 mm, respectively, which were comparable to the actual ground truth; the ground truth came from the labeling of clinicians. However, the Dice, MIoU, PA and AVD values of U-Net were 43.19%, 65.57%, 86.22% and 74.82 mm, and those of Res-U-Net were 58.65%, 72.53%, 88.98% and 57.30 mm. Overall, our data suggest our improved U2-Net model might be used for segmentation of ultrasound median neural images.

A Novel Ultrasonographic Anthropometric-Independent Measurement of Median Nerve Swelling in Carpal Tunnel Syndrome: The "Nerve/Tendon Ratio" (NTR)

Background: There is little consensus on ultrasound (US) normative values of cross-sectional area of median nerve (MN-CSA) in carpal tunnel syndrome (CTS) because of its dependency on anthropometric parameters. We aim to propose a novel anthropometric-independent US parameter: MN-CSA/flexor radialis carpi CSA (FCR-CSA) ratio (“Nerve Tendon Ratio”, NTR), in the diagnosis of clinically and electrodiagnostic (EDS)-defined CTS. Methods: 74 wrists of 49 patients with clinically defined CTS underwent EDS (scored by the 1−5 Padua Scale of electrophysiological severity, PS) and US of carpal tunnel with measurement of MN-CSA (at the carpal tunnel inlet), FCR-CSA (over scaphoid tubercle) and its ratio (NTR, expressed as a percentage). US normality values and intra-operator agreement were assessed in 33 healthy volunteers. Results: In controls, the mean MN-CSA was 5.81 mm2, NTR 64.2%. In 74 clinical CTS, the mean MN-CSA was 12.1 mm2, NTR 117%. In severe CTS (PS > 3), the mean MN-CSA was 15.9 mm2, NTR 148%. In CTS, both MN-CSA and NTR correlated with sensitive conduction velocity (SCV) (p < 0.001), distal motor latency (DML) (p < 0.001) and PS (p < 0.001), with a slight superiority of NTR vs. MN-CSA when controlled for height, wrist circumference and weight. In CTS filtered for anthropometric extremes, only NTR maintained a correlation with SCV (p = 0.023), DML (p = 0.016) and PS (p = 0.009). Diagnostic cut-offs were obtained with a binomial regression analysis. In those patients with a clinical diagnosis of CTS, the cut-off of MN-CSA (AUROC: 0.983) was 8 mm2 (9 mm2 with highest positive predictive value, PPV), while for NTR (AUROC: 0.987), the cut-off was 83% (100% with highest PPV). In patients with EDS findings of severe CTS (PS > 3), the MN-CSA (AUROC: 0.876) cut-off was 12.3 mm2 (15.3 mm2 with highest PPV), while for NTR (AUROC: 0.858) it was 116.2% (146.0% with highest PPV). Conclusions: NTR can be simply and quickly calculated, and it can be used in anthropometric extremes.

The Frequency of V122I Transthyretin Mutation in a Cohort of African American Individuals With Bilateral Carpal Tunnel Syndrome

Introduction

Hereditary transthyretin amyloidosis (hATTR) can cause multisystem organ disorders including polyneuropathy and cardiomyopathy. Amongst the many known pathologic mutations of the transthyretin (TTR) gene, the Val122Ile (V122I) mutation can be found in 3–4% of African Americans. Up to 47% of patients with the V122I hATTR cardiomyopathy had a history of carpal tunnel syndrome (CTS). This raises the question should we screen for this mutation in African Americans with bilateral CTS for the purpose of preventing advanced disease associated with hATTR. This is a prospective pilot study to determine the likelihood of African Americans with bilateral CTS having the V122I mutation and whether various clinical factors contribute to that probability.

Methodology

Adult African American patients without prior history of amyloidosis diagnosed with bilateral CTS were recruited for the study. They received genetic testing to screen for a TTR mutation. They also completed questionnaires to screen for symptoms of cardiomyopathy and neuropathy, other risk factors for CTS, and family history of CTS and cardiomyopathy.

Result

Two of the sixteen patients (12.5%) in this cohort were found to have the V122I mutation. The absence of polyneuropathy and cardiomyopathy symptoms, presence of other CTS risk factors, and absence of family history of CTS and cardiomyopathy did not decrease the likelihood of V122I mutation in this cohort.

Conclusion

The frequency of V122I transthyretin mutation in African Americans with bilateral CTS may be higher than 3–4%. The presence of bilateral CTS alone may be a justification to screen for TTR mutation in this population.

Difference and ratio of the cross-sectional area of median nerve at the carpal tunnel and the pronator quadratus muscle in diagnosing carpal tunnel syndrome: a cross-sectional study

Background

At present, the most commonly used diagnostic method of carpal tunnel syndrome (CTS) is based on clinical manifestations and electrophysiology, but the electrophysiology is not cheap, invasive, and lacks the presentation of peripheral nerve conditions, which is exactly the advantage of ultrasound (US). The purpose of this study was to evaluate the accuracy and effectiveness of US in the diagnosis of CTS by calculating the cross-sectional area (CSA) at the carpal tunnel and proximally at the level of the pronator quadratus muscle., and to find an appropriate index that can be used to achieve the diagnosis in a more cost-effective manner.

Methods

Forty-three wrists from 35 symptomatic CTS patients and 23 wrists from 18 asymptomatic volunteers were evaluated. Diagnosis in the CTS group was based on the American Academy of Neurology clinical diagnostic criteria. The ultrasonic probe was placed at the carpal tunnel and the distal 1/3 of the pronator muscle respectively, and the carpal tunnel cross-sectional area (CSAC) and the proximal cross-sectional area (CSAP) was calculated, with a further calculation of their difference (ΔCSA) and ratio (R-CSA).

Results

There was a significant difference between the 2 groups regarding mean ± standard deviation (SD) of CSAC, CSAP, ΔCSA, and R-CSA (P<0.01). The cutoff value of 12.14 mm² for CSAC had a sensitivity and specificity of 90.7% and 100%, respectively; the cutoff value of 1.235 mm² for R-CSA had a sensitivity and specificity of 97.67% and 95.65%, respectively; and the cutoff value of 2.035 mm² for ΔCSA had a sensitivity and specificity of 100% and 100%, respectively. Therefore, US was found to be an effective method for the diagnosis of CTS. Receiver operating characteristic curve (ROC) analysis of all patients showed area under the curve (AUC) was 0.9778 for CSAC, 0.9949 for R-CSA and 1.000 for ΔCSA.

Conclusions

US can provide reference values for the diagnosis of CTS. CSAC, ΔCSA, and R-CSA can be used for CTS diagnosis and evaluation. The ROC curve analysis showed that among the 3 values, ΔCSA was the most useful in the diagnosis of patients with CTS. ΔCSA is considered a valid diagnostic value for CTS, as its threshold of 2.04 mm² showed the highest sensitivity and specificity.

Occupational risk factors for work disability following carpal tunnel syndrome: a pooled prospective study

Background

Although recent studies have identified important risk factors associated with incident carpal tunnel syndrome (CTS), risk factors associated with its severity have not been well explored.

Objective

To examine the associations between personal, workplace psychosocial and biomechanical factors and incident work disability among workers with CTS.

Methods

Between 2001 and 2010 five research groups conducted coordinated prospective studies of CTS and related work disability among US workers from various industries. Workers with prevalent or incident CTS (N=372) were followed for up to 6.4 years. Incident work disability was measured as: (1) change in work pace or work quality, (2) lost time or (3) job change following the development of CTS. Psychosocial factors were assessed by questionnaire. Biomechanical exposures were assessed by observation and measurements and included force, repetition, duty cycle and posture. HRs were estimated using Cox models.

Results

Disability incidence rates per 100 person-years were 33.2 for changes in work pace or quality, 16.3 for lost time and 20.0 for job change. There was a near doubling of risk for job change among those in the upper tertile of the Hand Activity Level Scale (HR 2.17; 95% CI 1.17 to 4.01), total repetition rate (HR 1.75; 95% CI 1.02 to 3.02), % time spent in all hand exertions (HR 2.20; 95% CI 1.21 to 4.01) and a sixfold increase for high job strain. Sensitivity analyses indicated attenuation due to inclusion of the prevalent CTS cases.

Conclusion

Personal, biomechanical and psychosocial job factors predicted CTS-related disability. Results suggest that prevention of severe disability requires a reduction of both biomechanical and organisational work stressors.

Efficiency of 90-Min Extended EMLA-Induced Stimulated Skin-Wrinkling Test in the Diagnosis of Carpal Tunnel Syndrome

Background:

Previous researchers have used a 30-min eutectic mixture of local anesthetic (EMLA) test, which assesses the sympathetically mediated vasomotor function, in diagnosing carpal tunnel syndrome (CTS). However, its specificity was low, limiting its clinical diagnostic utility. In this study, we assessed the efficiency of 90-min extended EMLA-induced stimulated skin-wrinkling (SSW) test in CTS diagnosis.

Methods:

A cross-sectional study was designed among patients clinically diagnosed with CTS. Hands of healthy volunteers and the asymptomatic hands of selected patients served as control. The Boston symptom severity scale (SSS) and the neuropathic pain severity inventory (NPSI) were used to assess symptom severity, and nerve conduction study (NCS) was used to assess electrophysiological severity. EMLA-induced SSW was visually graded after 90 min of application and correlated with symptom and NCS severities.

Results:

Forty-two symptomatic hands and 30 asymptomatic hands were enrolled as cases and controls, respectively. The diagnostic efficiency of the extended EMLA test was found to be 83.4% for digit 2 and 87.3% for the lateral 4 digits (mean), whereas the diagnostic efficiency of standard NCS was 88.1%. Boston SSS and NPSI were better correlated with EMLA positivity than NCS positivity. A linear regression analysis showed negative correlation of wrinkling grade with NCS grade.

Conclusion:

With its improved diagnostic efficiency, the 90-min extended EMLA test can feasibly be used as an alternative to NCS, especially in general practice settings. Its potential clinical utility should be explored in a large population of CTS patients showing varying clinical and electrophysiological severities.

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

Objective

To examine the value of ultrasound (US) in the diagnosis of carpal tunnel syndrome (CTS) in the Vietnamese population.

Methods

This 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.

Results

Significant 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.

Conclusions

The 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

How to Report: Wrist MRI

Knowledge of the imaging anatomy of the wrist is essential for reporting magnetic resonance imaging (MRI). This familiarity should include the carpal bones, tendons (extensor and flexor compartments), triangular fibrocartilage complex (TFCC), intrinsic and extrinsic ligaments, and nerves, especially the median and ulnar nerves. Limitations of MRI in visualizing these structures, particularly the intrinsic ligaments and the TFCC, need to be considered. This article outlines the main features to comment on when reporting common conditions of the wrist on MRI, with some examples of terminology that can be used to describe these abnormalities.

Accuracy of diagnostic clinical tests and questionnaires in screening for carpal tunnel syndrome among workers- A systematic review

OBJECTIVE

To synthesize and appraise the evidence on the diagnostic accuracy of the clinical examination tests and questionnaires for screening carpal tunnel syndrome (CTS) among workers.

DESIGN

Systematic review of diagnostic test accuracy METHODS: Electronic search of 3 online databases (CINAHL, Embase, Medline) was done on August 31, 2020. Studies reporting the diagnostic accuracy of clinical examination tests in workers, compared to a reference standard test, were included. Diagnostic accuracy measures such as sensitivity (Sn) and specificity (Sp) were extracted and reported for different clinical examination tests. The risk of bias and applicability concerns were rated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool by 2 independent reviewers. Diagnostic tests accuracy extension of the PRISMA guidelines were followed.

RESULTS

Twelve studies reporting on the diagnostic accuracy of the clinical examination tests for workers suspected of CTS were included. Fourteen different clinical examination tests were evaluated in the studies, including sensorimotor, provocative maneuvers, questionnaires, and hand symptom diagrams (HSD). Ten of the included studies had an either unclear or high risk of bias. The most accurate tests to diagnose CTS in workers were the Katz HSD (with Sn ranging from 38%-93%, and Sp ranging from 25%-89%) and Kamath and Stothard questionnaire (Sn and Sp = 100%). Combination of Katz HSD with either the Phalen's maneuver or the Tinel's sign resulted in excellent Sp (83% and 89%, respectively).

CONCLUSIONS

Low to moderate quality evidence indicates variability in individual clinical examination tests used to screen for CTS in workers. Diagnostic self-report tools consisting of hand diagrams and/or diagnostic questions provide low burden and high accuracy. Still, they require more rigorous investigation about their value alone or in combination with clinical assessment tests.

Idiopathic carpal tunnel syndrome and de Quervain's tenosynovitis: is there an association?

AIM

In this study, we aimed to investigate frequency of de Quervain's tenosynovitis (DQT) in patient with idiopathic carpal tunnel syndrome (ICTS).

MATERIAL AND METHODS

We evaluated 356 hands of 310 patients who applied with the pre-diagnosis of ICTS. Patients who have pain over the radial styloid, pain on movement, tenderness over the first dorsal extensor compartment and also positive Finkelstein's test were accepted clinically DQT. Presence of DQT was confirmed by ultrasonography. Motor and sensory conductions of median and ulnar nerves were studied in every hand with the pre-diagnosis of ICTS.

RESULTS

We determined ICTS in 302 (85%) hands. De Quarvain's tenosynovitis ratio was found to be 9.9% in hands with ICTS (n:302). In patients with ICTS and DQT in the same hand, the male-to-female ratio is 1/3. There were 29 cases (22 female, 7 male) with ICTS and DQT. Of the 30 hands with ICTS and DQT together; 18 had mild, nine had moderate, and 3 had severe ICTS.

CONCLUSION

This is the first study that evaluates the DQT and ICTS together. We found that patients with ICTS have a prevalence higher than normal population to have DQT. We suppose that considering DQT in patients with the pre-diagnosis of ICTS during clinical evaluation has a positive impact on clinical follow-up and treatment of these patients.

Does Recurrence of Carpal Tunnel Syndrome (CTS) after Complete Division of the Transverse Ligament Really Exist?

The aim of this study was to evaluate whether recurrent carpal tunnel syndrome (CTS) after complete and sufficient division of the transverse ligament really exists. Another goal was to analyze the underlying reasons for recurrent CTS operated on in our department. Over an observation period of eleven years, 156 patients underwent surgical intervention due to CTS. The records of each patient were analyzed with respect to baseline data (age, gender, affected hand), as were clinical signs and symptoms pre- and postoperatively. To assess long-term results, standardized telephone interviews were performed using a structured questionnaire in which the patients were questioned about persisting symptoms, if any. Of the 156 patients, 128 underwent first surgical intervention due to CTS in our department. In long-term follow-up, two-thirds of these patients had no symptoms at all; one-third of the patients described mild persisting numbness. None of the patients experienced a recurrence of CTS. The 28 patients who received their first operation outside of our department were operated on for recurrent CTS. The cause of recurrence was incomplete division of the distal part of the transverse carpal ligament in all cases. The results suggest that recurrent CTS after complete and sufficient division of the transverse ligament is very unlikely.

MRI of carpal tunnel syndrome: before and after carpal tunnel release

Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment syndrome. Magnetic resonance imaging (MRI) is increasingly used to diagnose CTS, exclude secondary causes of CTS, and investigate patients with persistent symptoms after carpal tunnel release. Median nerve compression may also be either subclinical in the early stages or present with atypical symptoms. Radiologists are therefore not infrequently the first to alert clinicians as to the possibly of subclinical or atypical CTS. This review shows the normal and abnormal appearances of the carpal tunnel before and after CTR.

Median-to-Ulnar Nerve Communication in Carpal Tunnel Syndrome: An Electrophysiological Study

The median-to-ulnar communicating branch (MUC) is an asymptomatic variant of the upper limb innervation that can lead to interpretation errors in routine nerve conduction studies. The diagnosis of carpal tunnel syndrome (CTS) or ulnar nerve lesions can be complicated by the presence of MUC. In this study, we describe electrophysiological features of MUC in CTS patients presenting to our clinic. We enrolled MUB cases from consecutive CTS patients referred to our laboratory between the years 2014 and 2019. MUC was present in 53 limbs (36 patients) from the studied population. MUC was bilateral in 53% of patients. MUC type II was the most common subtype (74%), followed by types III and I; more coexisting MUC types were found in the majority of tested limbs. A positive correlation was demonstrated between the severity of CTS and the presence of positive onset, faster CV, or a double component of the compound muscle action potentials. We emphasize the importance of suspecting the presence of MUC in CTS in the presence of a positive onset or a double component in routine motor conduction studies.

Evaluation of occupational and non-occupational risk factors associated with carpal tunnel syndrome in dentists

BACKGROUND

Musculoskeletal disorders are very prevalent among dentists. Of these disorders, carpal tunnel syndrome (CTS) is notable.

OBJECTIVE

The aim of this study was to investigate the relationship between the occupational and non-occupational risk factors and CTS among dentists.

METHODS

It is a cross-sectional study. We evaluated 106 dentists from dental schools in Tehran. We collected data by a general questionnaire, a hand diagram, and physical examination. A nerve conduction velocity (NCV) test was used to confirm the diagnosis of CTS. The analysis was performed using an independent T-test and logistic regressions on SPSS software.

RESULTS

The prevalence of CTS among dentists was 17.9%. Significant risk factors of CTS included: vibration exposure greater than two hours per day (OR: 2.5), a wrist diameter ratio of greater than 0.7 (OR: 10.14), and female sex (OR: 13.38).

CONCLUSIONS

Exposure to the hand-arm vibration should be considered as an occupational risk factor for CTS in dentists. Female dentists should take more preventive measures.

Ultrasonography Findings of the Carpal Tunnel after Endoscopic Carpal Tunnel Release for Carpal Tunnel Syndrome

Objective

To investigate changes in the median nerve, retinaculum, and carpal tunnel on ultrasound after successful endoscopic carpal tunnel release (ECTR).

Materials and Methods

This prospective study involved 37 wrists in 35 patients (5 male, 30 female; mean age ± standard deviation [SD], 56.9 ± 6.7 years) with primary carpal tunnel syndrome (CTS). An in-house developed scoring system (0–3) was used to gauge the clinical improvement after ECTR. Ultrasound was performed before ECTR, and at 1, 3, and 12 months post-ECTR. Changes in the median nerve, flexor retinaculum, and carpal tunnel morphology on ultrasound after ECTR were analyzed. Ultrasound parameters for different clinical improvement groups were compared.

Results

All patients improved clinically after ECTR. The average clinical improvement score ± SD at 12 months post-ECTR was 2.2 ± 0.7. The median nerve cross-sectional area proximal and distal to the tunnel decreased at all time intervals post-ECTR but remained swollen compared to normal values. Serial changes in the median nerve caliber and retinacular bowing after ECTR were more pronounced at the tunnel outlet than at the tunnel inlet. The flexor retinaculum had reformed in 25 (68%) of 37 wrists after 12 months.

Conclusion

Postoperative changes in median nerve and retinaculum parameters were most pronounced at the tunnel outlet. Even in patients with clinical improvement after ECTR, nearly all ultrasound parameters remain abnormal at one year post-ECTR. These ultrasound parameters should not necessarily be relied upon to diagnose persistent CTS after ECTR.

Is there an association between the Hand Diagram and Electrodiagnostic Testing for Carpal Tunnel Syndrome?

Objective  Verify if there is an association between the hand diagram of paresthesia (HDP) and the results of electroneuromyography (ENMG) in the diagnosis of carpal tunnel syndrome.

Methods  A total of 92 people filled in a schematic drawing of the hand with the exact location of the paresthesia (167 hands). The main author classified the diagrams according to the criteria of Katz et al. 5 The results of the HDP were crossed with the positive results of ENMG for the diagnosis of carpal tunnel syndrome.

Results  The possible pattern of the HDP was prevalent both in isolation and after crossing with the degrees of ENMG.

Conclusion  There was no association between the HDP and ENMG in the diagnosis of carpal tunnel syndrome.

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.

Combination of high-frequency ultrasound and virtual touch tissue imaging and quantification improve the diagnostic efficiency for mild carpal tunnel syndrome

Background

Carpal tunnel syndrome (CTS) is the most common entrapment symptom in the peripheral nerves. High-frequency ultrasound (HFUS) is widely used in the diagnosis of CTS. Virtual Touch Tissue Imaging and Quantification (VTIQ), which provides more information about the hardness of organization, is used to diagnose CTS. However, the data of diagnostic value of them in various degrees of CTS are limited. Whether the combination of HFUS and VTIQ can improve the diagnostic efficiency also remains unknown. The study aimed to explore the diagnostic value of HFUS and VTIQ in various degrees of CTS and whether combination of HFUS and VTIQ could improve the diagnostic efficiency of CTS.

Methods

A collection and analysis of 133 CTS patients and 35 volunteers from January 2016 to January 2019 were performed. We compared the clinical characteristics, cross-sectional area (CSA) value and shear wave velocity SWV_mean value of CTS group with volunteer group.

Results

The CSA value and SWV_mean value of CTS cohort were significantly higher than volunteer group (10.79 ± 2.88 vs. 8.06 ± 1.39, p < 0.001, 4.36 ± 0.95 vs. 3.38 ± 1.09, p < 0.001, respectively). The area under the curve (AUC) of receiver operating characteristic (ROC) curve of CSA value and SWV_mean value were 0.794 and 0.757, respectively. Hierarchical analysis of CSA value and SWV_mean value showed that the AUC in the moderate and severe CTS group were higher than in mild CTS group. Furthermore, the CSA value combined with SWV_mean value used to diagnose mild CTS was 0.758, which was higher than that of single CSA value or single SWV_mean value.

Conclusions

Both HFUS and VTIQ technology were feasible to evaluate CTS. HFUS was suitable for use in diagnosis of moderate and severe CTS. For mild CTS, combination of HFUS and VTIQ was relevant to improve the diagnostic efficiency of CTS.

Elbow tendinopathy and occupational biomechanical overload: A systematic review with best-evidence synthesis

OBJECTIVES

To evaluate the evidence of an association between occupational and non-occupational exposure to biomechanical risk factors and lateral elbow tendinopathy, medial elbow tendinopathy, and olecranon bursitis.

METHODS

We carried out a systematic review of the literature. We searched MEDLINE (up to November 2019) and checked the reference lists of relevant articles/reviews. We aimed to include studies where (a) the diagnosis was based on physical examination (symptoms plus clinical signs) and imaging data (if any); and (b) the exposure was evaluated with video analysis and/or direct measurements. A quality assessment of the included studies was performed along with an evaluation of the level of evidence of a causal relationship.

RESULTS

We included four studies in the qualitative synthesis: two prospective cohorts and two cross-sectional studies. All the included studies investigated "lateral/medial epicondylitis", albeit the diagnosis was not supported by imaging techniques. Two cohort studies suggested that a combination of biomechanical risk factors for wrist/forearm is associated with increased risk of "lateral epicondylitis". This association was not observed in the two included cross-sectional studies. The cohort studies suggested that a Strain Index score higher than 5 or 6.1 could double the risk of "lateral epicondylitis". No association with increased risk of "medial epicondylitis" was observed.

CONCLUSIONS

There is limited evidence of a causal relationship between occupational exposure to biomechanical risk factors and lateral elbow tendinopathy. For medial elbow tendinopathy, the evidence is insufficient to support this causal relationship. No studies on olecranon bursitis and biomechanical overload were identified.

Carpal Tunnel Release Despite Normal Nerve Conduction Studies in Carpal Tunnel Syndrome Patients

PURPOSE

Carpal tunnel syndrome (CTS) is a common entrapment neuropathy, often requiring carpal tunnel release (CTR) surgery. Often, a nerve conduction study (NCS) is performed before CTR; however, there are various reports questioning the sensitivity of NCS, and some patients do undergo CTR despite normal NCS results. We had the following purposes: (1) to report clinical outcome of CTS patients who undergo CTR despite normal NCS, (2) to identify the characteristics and compare those with abnormal NCS patients in terms of basic features and risk factors, and (3) to analyze and compare normal and abnormal NCS results.

MATERIALS AND METHODS

Medical records of 546 CTS (30 normal NCS and 516 abnormal NCS) patients were retrospectively reviewed. Of 30 normal NCS patients, 7 were excluded, leaving 23 patients in the experimental group. We investigated the influence of age, sex, operative arm, and body mass index, as well as medical conditions known to be risk factors for CTS. In normal NCS patients, as a functional score, we investigated Boston carpal tunnel scores before and after CTR. The NCS results were compared in terms of median motor and median sensory testing. In normal NCS patients, NCS data were compared with that of the contralateral nonoperated wrists.

RESULTS

There were 18 women and 5 men in the normal NCS group (mean age 43.7 years). On physical examination, 22 (94.7%) patients showed a positive Tinel test, 19 (82.6%) showed a positive Phalen test, 8 (34.8%) complained of nocturnal paresthesia, and only 1 (4.3%) presented with thenar atrophy. In 19 of 23 patients, the Boston CTS scores showed significant improvement after CTR. Normal NCS patients were significantly younger and significantly heavier and more likely to be a current smoker. In NCS analysis of normal NCS patients, the operated wrists were closer to the reference values than nonoperated wrists.

CONCLUSIONS

Surgeons should evaluate the possibility of other combined lesions before CTR in normal NCS patients. Normal NCS can be present with a CTS diagnosis, especially in younger patients. Nevertheless, CTR after failed conservative management, despite normal NCS, could relieve subjective symptoms and function.

"Validation of a spanish version of the 'Unité Rhumatologique Des Affections De La Main' (URAM) scale"

BACKGROUND

In health care, quality-of-life surveys and questionnaires related to care are becoming increasingly important as a measure of its quality. There is currently no Spanish version of the Unité Rhumatologique des Affections de la Main (URAM) scale, which makes it suitable for hand pathology. The purposes of this study are to develop a Spanish version of the URAM and perform a transcultural adaptation of it, analyzing the result for reliability, validity, and sensitivity to changes.

METHODS

The questionnaire was evaluated for patients with Dupuytren's disease and Carpal Tunnel Syndrome. The cohort study subjects were interviewed at three points in time (baseline, three days after intervention, and one month after), administering the QuickDASH, URAM, and SF-12 (CF12 = physical component, CM12 = mental component) questionnaires at baseline and after intervention; and only the URAM at 3 days. Content validity was evaluated using Cronbach's α. The distribution of the factorial loads of the items and the pattern of the answers were checked. Responsiveness was evaluated by the size of the effect and the reliable rate of change. Convergent and divergent validity was performed using Spearman's r between the different questionnaires.

RESULTS

The study was conducted with 106 patients. The mean baseline scores were: URAM = 14.8, QuickDASH = 41.6, CF12 = 39.3 and CM12 = 49.4. Ceiling or floor effects were not observed in the Spanish URAM. The Cronbach α = 0.853 explains 49.6% of the variance. The study had a high reproducibility (intraclass correlation coefficient (ICC) = 0.939). Size effect, measured as differences in scores, was moderate for URAM (-0.69) and QuickDASH (-0.51); and low for CF12 and CM12. The correlation of URAM with QuickDASH was high (r = 0.716), and moderate with DD and CTS.

CONCLUSION

The Spanish version of the URAM is a valid and reliable tool for use in assessing hand pathology.

MRI of the Carpal Tunnel 3 and 12 Months After Endoscopic Carpal Tunnel Release

OBJECTIVE. The purpose of this study was to study changes in the median nerve, retinaculum, and carpal tunnel on MRI after successful endoscopic carpal tunnel release (ECTR). SUBJECTS AND METHODS. In this prospective study, 35 wrists in 32 patients (five men, 27 women; mean age, 56.7 ± 6.8 [SD] years) with nerve conduction test-confirmed primary carpal tunnel syndrome were evaluated from May 2013 to September 2016. Clinical scores ranging from 0 to 4 (no improvement to symptoms completely resolved) and MRI morphologic features of median nerve and carpal tunnel were evaluated at baseline and 3 and 12 months after ECTR. The paired t test was used to compare MRI parameters before and after ECTR and their relationships to clinical improvement scores. RESULTS. All patients' conditions improved after ECTR with mean clinical improvement scores of 2.94 ± 1.0 at 3 months and 3.49 ± 0.56 at 12 months. Although median nerve swelling did decrease proximally, the nerve remained swollen (> 15 mm²) and flattened in all areas, even 12 months after ECTR. Additional changes occurred in median nerve caliber-change ratio, relative signal intensity, and carpal tunnel cross-sectional area. A retinacular gap was present in 33 (94%) wrists 3 months and six (17%) wrists 12 months after ECTR, and increased retinacular bowing persisted. CONCLUSION. After ECTR, undue swelling and flattening of the median nerve persist as long as 12 months after surgery, even in patients with a good surgical outcome. One should be wary of using these MRI findings as signs of persistent neural compression. The retinaculum reforms in most patients within 12 months of surgery but with a more bowed configuration.

High prevalence of carpal tunnel syndrome in individuals with rare nerve growth factor-beta mutation

In Sweden, a large family with a point mutation in the nerve growth factor-beta gene has previously been identified. The carriers of this mutation have reduced small-fibre density and selective deficits in deep pain and temperature modalities. The clinical findings in this population are described as hereditary sensory and autonomic neuropathy type V. The purpose of the current study was to investigate the prevalence of carpal tunnel syndrome in hereditary sensory and autonomic neuropathy type V based on clinical examinations and electrophysiological measurements. Furthermore, the cross-sectional area of the median nerve at the carpal tunnel inlet was measured with ultrasonography. Out of 52 known individuals heterozygous for the nerve growth factor-beta mutation in Sweden, 23 participated in the current study (12 males, 11 females; mean age 55 years; range 25–86 years). All participants answered a health questionnaire and underwent clinical examination followed by median nerve conduction study in a case–control design, and measurement of the nerve cross-sectional area with ultrasonography. The diagnosis of carpal tunnel syndrome was made based on consensus criteria using patient history and nerve conduction study. The prevalence of carpal tunnel syndrome in the hereditary sensory and autonomic neuropathy group was 35% or 52% depending on whether those individuals who had classic symptoms of carpal tunnel syndrome but negative nerve conduction studies were included or not. Those who had a high likelihood of carpal tunnel syndrome based on classic/probable patient history with positive nerve conduction study had a significantly larger median nerve cross-sectional area than those who had an unlikely patient history with negative nerve conduction study. The prevalence of carpal tunnel syndrome was 10–25 times higher in individuals heterozygous for the nerve growth factor-beta mutation than the general Swedish population. Further studies are needed to better understand the underlying pathophysiological mechanisms.

Post-surgical complications of median nerve release at the wrist level

Carpal tunnel syndrome is a set of signs and symptoms caused by compression of the median nerve as it travels through the wrist at the carpal tunnel. The diagnosis is clinical and based on the presence of characteristic signs and symptoms. Proper nonsurgical treatment can stop the progression of this disorder and prevent the development of permanent disability. Surgical treatment may be indicated to patients with complications rated as moderate to severe. Although the surgery is relatively simple, basic antisepsis care before, during, and after the procedure, and guidance of patients for the management of wound hygiene upon discharge, make recovery more secure and prevent disabling sequelae. We report a case of a patient that had infection, edema, and temporary loss of flexibility of the fingers after a surgical procedure to release the median nerve.

Criteria for diagnosis and attribution of an occupational musculoskeletal disease

BACKGROUND

Criteria for diagnosis and compensation of occupational musculoskeletal diseases varies widely between countries as demonstrated by the large differences between countries with comparable economics and social systems (for example, within the European Union). Several countries have a list of occupational diseases and sometimes these lists include diagnostic and attribution criteria, but these criteria are usually not very specific, and they may also be very different.

OBJECTIVES

The aim of this paper is to explicitly define what are the information needed for an evidence-based diagnosis and attribution of an occupational musculoskeletal disease.

METHODS

Based on the general framework of evidence-based medicine, a review is presented of the information required to define: - when a musculoskeletal disease is present, according to the best available techniques; - how to define a relevant exposure to biomechanical risk factors, according to the best available techniques.

RESULTS

Criteria are presented to combine information regarding the diagnosis of a musculoskeletal disease and exposure to biomechanical risk factors for an evidence-based attribution of the disease to the occupational exposure. The criteria use a probabilistic model that combine epidemiologic and medical findings, workplace exposure assessment, and non-occupational factors evaluation.

DISCUSSION

The use of the proposed criteria may improve the process of diagnosis and attribution of an occupational musculoskeletal disease. In addition, it makes possible to associate a probability rank to the attribution and, ultimately, it may improve the overall quality of the decisional process of the occupational physician.

Diagnosis Accuracy of Carpal Tunnel Syndrome in Diabetic Neuropathy

Background and objectives: Carpal tunnel syndrome (CTS) is a common pathology, but sometimes the diagnosis is delayed in patients with diabetic neuropathy (DN). The aim of the study is twofold: first, to compare the accuracy of ultrasound (US) with that of electroneurography (ENG) in the diagnosis of CTS associated with DN, using the clinical diagnosis as a reference standard, and second, to investigate the correlation between morphological US parameters and electrodiagnosis (EDX) measurements in patients with CTS and DN. Materials and Methods: This study included patients with DN. They were divided into two groups: Control (patients without CTS) and Cases (patients with CTS). We performed US and ENG in both hands, totaling 56 wrists, with 28 wrists in each group. Results: We found that the difference in the sensory distal latencies between the median and the ulnar nerves (ring finger) exhibited the highest diagnostic accuracy of all the US and ENG parameters, areas under the receiver operating characteristic (AUC) = 0.99 (95% CI 0.97–1), and it was significantly different from the best US diagnostic method. The wrist cross-sectional area (CSA) had the most accurate US diagnosis, while the wrist-to-forearm ratio had the worst AUC. Moreover, in the group of CTS and DN patients, the wrist CSA enlargement was statistically directly proportional to the median compound muscle action potential (CMAP) distal latency and inversely proportional to the antidromic median nerve conduction study (NCS) and the orthodromic median palm–wrist NCS. Conclusions: Both examinations can be used with confidence in the diagnosis of CTS overlapping with DN, but the EDX examination seems to be more accurate. Furthermore, we found a positive correlation between the US and EDX parameters.

Work Conditions, Social Incorporations, and Foodborne Diseases Risk: Reflections About the (Non)Compliance of Food Safety Practices

The number of foodborne diseases has increased in all continents, and efforts must be made to control this urgent and expressive public health problem. This article aims to present and discuss situations related to the compliance and noncompliance of food safety practices (FSPs) in light of Bourdieu's social theory. This qualitative study was conducted in commercial restaurants in two cities in São Paulo, Brazil. Participant observation was used in the restaurants, and notes referring to the kitchen workers and their bosses' work processes were registered in field journals. Thematic type content analysis was used to determine the meaning cores of field journals. It was found that aspects inherent to convenience and haste at work, deficient infrastructure, lack of employees, negative boss examples, exposure to noise, and body pain experienced by workers can contribute to noncompliance of FSPs and consolidate in the habitus and practical sense some dispositions that can increase the risk of foodborne diseases. This study highlights the necessity of creating environments that address food safety, which means being able to perform a service properly.

Ultrasound (US) Changes in the Median Nerve Cross-Sectional Area After Microinvasive US-Guided Carpal Tunnel Release

OBJECTIVE

To document changes in the median nerve cross-sectional area (CSA) in the proximal carpal tunnel region after ultrasound (US)-guided carpal tunnel release (CTR).

METHODS

Prospective data were collected on 23 consecutive patients (37 wrists) treated with US-guided CTR by the primary author using the same office-based microinvasive technique. Ultrasound was used to measure the largest CSA of the median nerve in the proximal carpal tunnel region both preoperatively and postoperatively. The primary outcome measure was the change in the preoperative versus 6- to 10-week postoperative median nerve CSA.

RESULTS

The mean CSA of the median nerve decreased from 16.08 to 12.75 mm² at 6 to 10 weeks after US-guided CTR (P < .001). During the same period, the mean Boston Carpal Tunnel Questionnaire (BCTQ) symptom score decreased from 3.23 to 1.67 (P < .001), and mean BCTQ functional score decreased from 2.49 to 1.47 (P < .001), both exceeding minimal clinically important differences. Although the primary end point was the median nerve CSA at 6 to 10 weeks, statistically significant reductions in the median nerve CSA, as well as BCTQ scores, were also observed as early as 2 to 4 weeks after US-guided CTR (median nerve CSA, 12.40 mm² ; BCTQ symptom score, 2.00; BCTQ functional score, 1.75; all P ≤ .03).

CONCLUSIONS

To our knowledge, this investigation was the largest to date examining changes in the proximal median nerve CSA after US-guided CTR. Statistically significant reductions in the proximal median nerve CSA were observed within 6 to 10 weeks after ultrasound-guided CTR. These reductions were similar to those previously reported for open and endoscopic CTR and validate the ability of US-guided CTR to relieve median nerve compression.

Comparison of two approaches for carpal tunnel release: Extended versus mini-open technique

Objectives

This study aims to describe a retrospective study using prospectively gathered data to compare mini-open and extended open release techniques for moderate to severe carpal tunnel syndrome (CTS).

Patients and methods

The data of 198 consecutive patients (139 males, 59 females; mean age 57.0±4.5 years; range, 44 to 75 years) treated for CPS were used. For matching, age, gender and severity of the compression, the Greathouse Ernst Halle Schaffer neurophysiological classification system was used. After matching, 63 observations in each group (group 1: mini-open and group 2: extended open) were used for analysis. A Jamar hydraulic hand dynamometer was used to measure pre- and postoperative third month grip strengths. The key pinch test was performed also at third month. Patients completed the Boston Carpal Tunnel Questionnaire at the last follow-up.

Results

Symptom severity and functional status were improved up to half fold in both groups at final follow-up; however, there was no statistically significant clinical difference between the groups (p>0.05). There were totally six patients with paresthesia symptoms (three in each group; 4.7%), which improved in three months. Eight patients (6.3%, one in group 1 and seven in group 2, p=0.032) had dysesthesia and pillar pain.

Conclusion

Mini-open and extended open carpal tunnel release have similar clinical outcomes without any major complications.

MRI criteria for diagnosis and predicting severity of carpal tunnel syndrome

OBJECTIVE

To study MRI criteria for diagnosing and predicting severity of carpal tunnel syndrome (CTS).

METHODS

Sixty-nine wrists in 41 symptomatic CTS patients and 32 wrists in 28 asymptomatic subjects were evaluated by MRI. Circumferential surface area (CSA), flattening ratio, relative median nerve signal intensity, and retinacular bowing were measured. CTS severity was classified as mild, moderate, or severe. Parameters for patients with and without CTS and for the three severity groups were compared. ROC curves were plotted to assess accuracy for CTS diagnosis and severity prediction.

RESULTS

Significant differences were found between CTS and control wrists for median nerve CSA, flattening ratio at inlet, relative median nerve signal intensity, and retinacular bowing. ROC curve analysis revealed a sensitivity, specificity, and accuracy of median nerve CSA > 15 mm² proximal to the tunnel (CSA_p) of 85.5, 100, and 90.1%. Using either CSA_p or CSA_d > 15 mm² as a diagnostic criterion, MRI could achieve a sensitivity of 100% and specificity of 94% for diagnosis of CTS while overall accuracy was 98%. Significant differences were found among the three severity groups. Sensitivity, specificity, and accuracy of prediction of severe CTS using for CSA_p > 19 mm² were 75.0, 65.9, and 69.6%, respectively.

CONCLUSIONS

MRI is highly accurate at diagnosing CTS and moderately accurate at determining CTS severity. We recommend using CSA > 15 mm² either proximal to or distal to the tunnel as a diagnostic criterion for CTS and CSA > 19 mm² proximal to the tunnel as a marker for severe CTS.

A novel approach to the diagnostic assessment of carpal tunnel syndrome based on the frequency domain of the compound muscle action potential

Conventional electrophysiological (EP) tests may yield ambiguous or false-negative results in some patients with signs and symptoms of carpal tunnel syndrome (CTS). Therefore, researchers tend to investigate new parameters to improve the sensitivity and specificity of EP tests. We aimed to investigate the mean and maximum power of the compound muscle action potential (CMAP) as a novel diagnostic parameter, by evaluating diagnosis and classification performance using the supervised Kohonen self-organizing map (SOM) network models. The CMAPs were analyzed using the fast Fourier transform (FFT). The mean and maximum power parameters were calculated from the power spectrum. A counter-propagation artificial neural network (CPANN), supervised Kohonen network (SKN) and XY-fused network (XYF) were compared to evaluate the classification and diagnostic performance of the parameters using the confusion matrix. The mean and maximum power of the CMAP were significantly lower in patients with CTS than in the normal group (p < 0.05), and the XYF network had the best total performance of classification with 91.4%. This study suggests that the mean and maximum power of the CMAP can be considered as less time-consuming parameters for the diagnosis of CTS without using additional EP tests which can be uncomfortable for the patient due to poor tolerance to electrical stimulation.

Diagnostic Use of Ultrasonography in Carpal Tunnel Syndrome and Its Correlation with the Chinese Version of Boston Carpal Tunnel Questionnaire

Introduction

There were yet no correlation studies performed between ultrasound and the Chinese version of Boston Carpal Tunnel Questionnaire (C-BCTQ). Besides, controversies still remain regarding the correlation between ultrasound and different language versions of BCTQ.

Purpose of the Study

To examine whether ultrasound can (i) reflect symptom severity and/or functional status, (ii) differentiate primary/secondary symptom, and (iii) correlate with subscale items in C-BCTQ.

Methods

Forty-two Chinese female individuals (aged 58.84 ± 9.02 years) with 73 hands were enrolled in the study. Factor analysis was used to identify the hidden factors of C-BCTQ. Correlations were examined between hidden factors, relevant subscale items of C-BCTQ, and ultrasound.

Results

Three factors were identified as Factor One (functional status, 36.534%), Two (sensory symptoms, 15.057%) and Three (pain, 11.867%), with 63.458% of total variance explained in C-BCTQ. All the ultrasound parameters were positively correlated with Factor One (r = 0.29-0.411, P < 0.05), while no correlations were found with Factor Two and Three. Meanwhile, correlation between wrist cross-sectional area and functional status scale (FSS) was also found (W-CSA, r = 0.266, P = 0.023), whereas no correlation was found with symptom severity scale (SSS), subscales of primary symptom (Paresthesia) and secondary symptom (pain) related items in C-BCTQ.

Conclusion

Morphological information via ultrasound can reflect the impact on functionality that carpal tunnel syndrome (CTS) exerted. However, it can be used neither to describe symptom severity nor differentiate primary/secondary symptom of CTS.

Eccentric contraction-induced muscle damage in human flexor pollicis brevis is accompanied by impairment of motor nerve

BACKGROUND

Eccentric contractions (ECCs) cause muscle damage. In addition, we showed that ECCs induce nerve dysfunction and damage with rats and human.

PURPOSE

We aimed to evaluate motor nerve conduction velocity (MCV) for flexor pollicis brevis muscle (FPBM) after ECCs.

METHODS

Twelve men (years, 19.8 ± 1.7 years; height, 172.4 ± 7.0 cm; weight, 64.0 ± 8.6 kg) performed maximal 100 ECCs on their FPBM of non-dominant hands with torque dynamometer. The dominant hands were control (CON). Maximal voluntary contraction (MVC), range of motion (ROM), DOMS, and MCV were assessed before, immediately post, and 1, 2, and 5 days after ECCs. MCV was calculated as the distance by stimulation divided by the latencies of the waveforms generated. Values were statistically analyzed by two-way ANOVA, and the significance level was set at P < .05.

RESULTS

Decreases in MVC immediately (-32.9%) to 5 days after ECCs were significantly greater (P < .05) than for the CON group. ROM showed a significant decrease immediately (-21.6%) after ECCs compared with before ECCs and CON group (P < .05). DOMS after ECCs increased at 1 and 2 days (5.0 cm) after ECCs compared with before ECCs and CON (P < .05). Also, MCV after ECCs delayed significantly from immediately (-36.4%), 1, 2, and 5 days after ECCs compared with CON (P < .05), while no significant change in M-wave amplitude was observed over time for both ECCs and CON.

CONCLUSION

The present study showed that ECCs of the FPBM cause a significant delay in MCV of median nerve.

A new method to define cutoff values in nerve conduction studies for carpal tunnel syndrome considering the presence of false-positive cases

BACKGROUND

Nerve conduction studies (NCS) are useful tools for diagnosing carpal tunnel syndrome (CTS). Establishing the normal values is the first step required for utilizing NCS for diagnosis. Previous epidemiological studies demonstrated the presence of fairly large number of false-positive subjects regarding NCS among control population, which has not been properly considered in past studies. This study proposed a new method to address this issue.

METHODS

Non-diabetic 144 CTS patients were retrospectively enrolled using clinically defined inclusion criteria. Controls consisted of 73 age-matched volunteers without hand symptoms. Six NCS parameters were evaluated including peak-latency difference by the thumb method (thumbdif) and that by the ring-finger method (ringdif). The Youden index of the receiver operator characteristic curve was used both to judge the sensitivity of a parameter and to identify false-positive cases that were thought to have subclinical median neuropathy at the wrist. The linear function of six parameters was constructed, and the coefficient for each parameter was variously changed.

RESULTS

When the Youden index took on the maximum value, seven control subjects (10%) were identified as false-positive and were excluded from the calculation of normal values. The most sensitive parameter before exclusion was thumbdif, whereas ringdif became the most sensitive after exclusion. The cut-off value for ringdif was 1.15 ms before exclusion, but was 0.37 ms after exclusion.

CONCLUSION

This method can be widely applied to solve the statistical problem when the gold standard is lacking, and the outside reference standard is not completely reliable.

Prospective Evaluation of Median Nerve Dysfunctions in Patients with a Distal Radius Fracture Treated with Volar Locking Plating

Background: The aim of this study was to identify the risk factors for median nerve dysfunctions after volar locking plate (VLP) fixation for distal radius fracture (DRF). Methods: We prospectively assessed the incidence of median nerve symptoms (MNS) such as numbness, pain, paresthesia, or hypesthesia in the area innervated by the median nerve and evaluated post-operative nerve conduction (NC) in 91 hands of 121 patients after VLP fixation for DRF. Multivariate logistic regression analysis was conducted to identify factors independently associated with MNS and abnormal NC in the injured wrist. Results: There were 18 cases (20%) of MNS on the injured side, 9 hands (10%) of both MNS and abnormal NC, 11 hands (12%) with only abnormal NC, and 9 hands with only MNS. Sensitivity, specificity, and diagnostic accuracy of abnormal NC for diagnosing MNS were 50%, 86%, and 78%, respectively. Four cases did not respond to conservative treatment and received carpal tunnel release concomitantly with plate removal. Logistic regression examination revealed that volar placement of the plate and short stature were significant independent predictors of MNS, while patient age was the sole independent predictor of abnormal NC. Conclusions: Our study demonstrated that plate prominence, short stature, and age were significant independent risk factors for median nerve dysfunctions after VLP fixation for DRF.

Efficacy of laser acupuncture for carpal tunnel syndrome: A study protocol for a prospective double-blind randomized controlled trial

INTRODUCTION

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy that causes hand discomfort and work disability. Since no satisfactory conventional treatments for mild to moderate CTS exist, we apply complementary alternative medicine (CAM) to this problem. Laser acupuncture (LA), a new, non-invasive therapy which uses low-level-laser therapy (LLLT) in acupuncture could help to manage CTS. However, only one small randomized, double-blind and crossover trial had been conducted, which is not enough to provide an evidence-based assessment of the effects of LA on CTS.

OBJECTIVES

The aim of this study protocol is to investigate the efficacy of LA therapy on patients with mild to moderate CTS through sonography of the median nerve and offer clear parameters of LLLT.

METHODS

This study protocol is a prospective double-blind randomized controlled trial. Forty subjects aged 20 to 80 years old and diagnosed as having mild to moderate CTS will be randomly assigned to the intervention group (real LA, 3-sessions a week for 2 weeks) and control group (sham LA, 3-sessions a week for 2 weeks). All subjects will be asked to wear night splints as the fundamental management approach. The laser parameters will include a wavelength of 808 nm, power output of 300 mW and power density of 300 mW/mm, with ten seconds of treatment for each acupuncture point (PC4, PC6, PC7, PC8, LI4, LI10, LI11, HT3, HT7, and LU10). Sham LA treatment will be applied without any laser power output. The primary outcome will be based the Boston Carpal Tunnel Syndrome Questionnaire and secondary outcomes included a visual analog scale, cross sectional area of median nerve by sonography and electrophysiological test before interventions and after 2, 4, 8, 12 weeks postintervention.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT03580265).