Risk Of Carpal Tunnel Syndrome Research Articles

Carpal tunnel syndrome and manual work: the OCTOPUS cohort, results of a ten-year longitudinal study.

The American Conference of Governmental Industrial Hygienists (ACGIH) proposed a method to assess the hand, wrist and forearm biomechanical overload based on exertions frequency (hand-activity level) and force use (normalized peak force). We applied the ACGIH threshold limit value (TLV)® method to a large occupational cohort to assess its ability to predict carpal tunnel syndrome (CTS) onset. A cohort of industrial and service workers was followed-up between 2000 and 2011. We investigated the incidence of CTS symptoms and CTS confirmed by nerve conduction studies (NCS). We then classified exposure with respect to action limit (AL) and TLV. Cox regression models including age, gender, body mass index, and presence of predisposing pathologies were conducted to estimate hazard ratios (HR) of CTS and population attributable fractions. We analyzed data from 3131 workers [females, N=2032 (65%); mean age at baseline 39.3, standard deviation (SD) 9.4 years]. We observed 431 incident cases of CTS symptoms in 8000 person-years and 126 cases of CTS confirmed by NCS in 8883 person-years. The ACGIH TLV® method predicted both CTS symptoms [HR between AL and TLV 2.18, 95% confidence interval (95% CI) 1.86-2.56; above TLV 2.07, 95% CI 1.52-2.81] and CTS confirmed by NCS (HR between AL and TLV 1.93, 95% CI 1.38-2.71; above TLV 1.95, 95% CI 1.27-3.00). About one third of CTS cases were attributable to exposure levels above the AL. The ACGIH TLV® method predicted the risk of CTS, but the dose-response was flat above the AL; a fine-tuning of the proposed thresholds should be considered.

A comparison of carpal tunnel syndrome between digital and paper textbook users in elementary schools.

There are advantages to using digital textbooks, but also health concerns yet to be evaluated. This study examines the use of digital textbooks' effects on carpal tunnel, considered one of the potential health risks in students using digital textbooks. Data were obtained from 43 elementary school students in the sixth grade, selected from two groups who had used digital and paper textbooks, respectively. To assess carpal tunnel function, this study performed median motor nerve and median sensory nerve conduction studies. There were no statistically significant differences between the groups, indicating that there were no functional differences related to carpal tunnel syndrome between the groups. Usage of digital textbook is expanding nationwide in the Republic of Korea. There is no short-term risk of carpal tunnel syndrome in this population of elementary school students.

Carpal tunnel syndrome: The role of collagen gene variants

IntroductionThe direct causes of idiopathic carpal tunnel syndrome (CTS) are still unknown. It is suggested that pathology of the tendons and other connective tissue structures within the carpal tunnel may play a role in its aetiology. Variants in genes encoding connective tissue proteins, such as type V collagen, have previously been associated with CTS. Since variants within other collagen genes, such as type I, XI and XII collagen, have previously been associated with modulating the risk of musculoskeletal soft tissue injuries, the aim of this study was to determine whether variants within COL1A1, COL11A1, COL11A2 and COL12A1 were associated with CTS. MethodsSelf-reported Coloured South African participants, with a history of carpal tunnel release surgery (CTS, n=103) and matched control (CON, n=150) participants without any reported history of CTS symptoms were genotyped for COL1A1 rs1800012 (G/T), COL11A1 rs3753841 (T/C), COL11A1 rs1676486 (C/T), COL11A2 rs1799907 (T/A) and COL12A1 rs970547 (A/G). ResultsThe TT genotype of COL11A1 rs3753841 was significantly over-represented in the CTS group (21.4%) compared to CON group (7.9%, p=0.004). Furthermore, a trend for the T minor allele to be over-represented in the CTS group (p=0.055) with a significant association when only female participants (p=0.036) were investigated was observed. Constructed inferred pseudo-haplotypes including a previously investigated COL5A1 variant, rs71746744 (−/AGGG), suggest gene–gene interactions between COL5A1 and COL11A1 modulate the risk of CTS. DiscussionThese findings provide further information of the role of the genetic risk factors and the possible role of variations in collagen fibril composition in the aetiology of CTS. Genetic factors could potential be included in models developed to identify indivisuals at risk of CTS. Strategies that target modifiable risk factors to mitigate the effect of non-modifiable risk factors, such as the genetic risk, could be also developed to reduce incidence and morbidity of CTS.

Non-Occupational Risk Factors for Carpal Tunnel Syndrome: A Review

Context: Carpal tunnel syndrome (CTS) is a common neuropathy accounting for up to 90% of all entrapment neuropathies of the upper limb. Identifying potential risk factors might aid in the prevention of this injury. This systematic review aims to identify the current known non-occupational risk factors for CTS as published in three electronic databases. Evidence Acquisition: Three electronic databases PubMed, Web of Knowledge, and SpringerLink were searched using the keywords “CARPAL TUNNEL SYNDROME RISK” for all published articles up to September 2015. Based on the inclusion and exclusion criteria, 2755 unique titles were independently analyzed and narrowed to a final list of 83 articles. Only articles with a level of evidence of I, II, or III were included, in accordance with robust study design and data analysis methods. The level of certainty for each risk factor was determined using previously defined criteria. Results: A total of 83 articles were included, which defined 29 individual, non-occupational risk factors. Only sex and previous musculoskeletal disorder/injury were found to have a moderate level of certainty to modify the risk of CTS. All other risk factors were evaluated as having a low level of certainty. Conclusions: Considering the large number of studies reporting on non-occupational CTS risk factors as well as the differences in reporting between studies, a lack of consistency is observed in the current review. This review does, however, offer a broad outlook on the literature and the current evidence for risk factors commonly believed to be associated with altered CTS risk. Although several risk factors are commonly believed to be associated with altered risk of CTS, the current evidence to support these beliefs is limited. Prospective cohort studies, larger sample sizes, and consistent and robust measures of risk should be used in future research.

Body mass index as predictor of carpal tunnel syndrome among garment workers

Of the nerve entrapment syndromes the most well-known is the carpal tunnel syndrome (CTS) involving the median nerve. In the field of occupational medicine this condition is categorized as an occupational disease, for which industrial workers may claim compensation if the CTS occurs as a consequence of their job. However, although several occupational risk factors have been suggested as causing the development of CTS, a definitive role of work activities as the central cause of CTS is unclear. The aim of the present study was to evaluate both non-occupational and occupational factors associated with CTS in garment home-industry workers. A cross-sectional study was performed from April to June 2008 in the garment home industry in North Jakarta. A total of 99 workers, consisting of 45 males and 54 females were included in this study. Historical data were obtained from a self-administered detailed questionnaire, while anthropometric and provocative median nerve test variables were measured directly. The results showed that body mass index (BMI) was a significant predictor of CTS in male workers (p=0.031), while the risk of CTS was three-fold higher in female workers using hormonal contraceptives (Prevalence Ratio/PR = 3.3 ; 95% Confidence of Interval/CI = 1.0 – 10.5). In conclusion it appears that BMI and hormonal contraceptive use were CTS predictors.

Carpal Tunnel Syndrome Associated with Oral Bisphosphonates. A Population-Based Cohort Study

BackgroundBisphosphonates are widely used to prevent osteoporotic fractures. Some severe musculoskeletal reactions have been described with this medication; among them, some cases of carpal tunnel syndrome. Thus, the aim of this study was to explore whether bisphosphonates may be associated with this syndrome.MethodsA cohort study was conducted to compare exposed to unexposed women; the exposed group was that composed of women having received at least one prescription of an oral bisphosphonate. For the purpose, we used information from The Health Improvement Network (THIN) database. The outcome of interest was defined as those women diagnosed with carpal tunnel syndrome. A survival analysis was performed; the Cox proportional hazard model was used to calculate hazard ratios and 95% confidence intervals, and to adjust for identified confounding variables.ResultsOut of a sample of 59,475 women older than 51 years, 19,825 were treated with bisphosphonates during the period studied. No differences in age distribution or mean follow-up time were observed between the two groups in comparison. Overall, there were 572 women diagnosed with carpal tunnel syndrome, 242 (1.2%) in the group exposed to bisphosphonates, and 330 (0.8%) in the unexposed. An adjusted hazard ratio of developing carpal tunnel syndrome of 1.38 (95%CI, 1.15–1.64) was found for women exposed to bisphosphonates; no significant changes in the hazard ratios were found when considering different levels of bisphosphonate exposure.ConclusionsAn increased risk of carpal tunnel syndrome is associated with the use of bisphosphonates in postmenopausal women.

PREVALENCE AND RISK FACTOR OF CARPAL TUNNEL SYNDROME AMONG WORKERS IN THE CONSTRUCTION INDUSTRY

Introduction: In terms of lost-work time, restricted workdays and rehabilitation, one of the most costly occupational musculoskeletal disorders is carpal tunnel syndrome (CTS). Aim of work: determination of CTS prevalence and evaluation of some personal and occupational risk factors among construction workers. Materials and Methods: In this descriptive cross-sectional study, 116 cases were enrolled. A questionnaire was used to assess socio-demographic data, and occupational history. CTS was assessed by symptoms on the Katz hand diagram and physical examination. Phalen’s test was done for all participants. Results: According to this study, the prevalence of CTS was 27.6% among workers in construction industry. The rate of CTS was significantly higher among electricians than in other workers (P < 0.05). The risk of developing CTS increase with age ≥ 30 years and work duration ≥ 5 years. Conclusion: Our findings suggest that construction workers are at an increased risk of CTS, so awareness should be raised and interventions should specifically target this risk group.

Use of Aromatase Inhibitors Raises Risk for Carpal Tunnel Syndrome

Carpal tunnel syndrome (CTS) results from compression of the median nerve in the wrist as it courses from the arm to the hand. In a large double-blind

Trapeziohamate Distance in Carpal Tunnel View as a Risk Factor for Carpal Tunnel Syndrome

Background: Carpal tunnel syndrome (CTS) is the most frequent entrapment syndrome of the upper limp, which leads to compression of the median nerve at the level of the wrist. Any early diagnosis based on the radiological and clinical findings is essential to find a risk factor preventing permanent nerve damage and functional sequelae. Objectives: The main aim of this study was to evaluate and determine trapeziohamate distance as a risk factor for incident CTS. Patients and Methods: The subjects in this case-control study were patients divided into an experimental group (n = 38) and control group (n = 23). Prospective study was conducted on 33 female and 5 male patients with CTS and 21 females and 2 males in control group. Subjects were selected from patients and their relatives who referred to our hand surgery department. In total, 61 subjects were examined. Gender and age as the personal factors, dominant hand, diabetes mellitus (DM), occupation and trapeziohamate distances were evaluated in all patients and control group. Mean values of trapeziohamate distance as a risk factor for experimental and control groups were measured. Levene’s test and Student’s t test were used to analyse the collected data using Statistical Package for Social Science. Results: The risk of CTS was higher in women and housekeeper. There was a significant difference between the two groups for trapeziohamate distance. The mean of trapeziohamate distance in control group (23.39) was significantly higher than the mean of experimental group (21.02). Conclusions: Our study confirmed that the incidence of CTS is higher in women and housekeeper and trapeziohamate distance is a dependent risk factor for the carpal tunnel syndrome.

Sonographic examination of the median nerve in dialysis patients and after renal transplantation.

Patients with renal insufficiency are predisposed to develop CTS (carpal tunnel syndrome). In particular, long-term dialysis seems to contribute to changes in median nerve texture which lead to an increased risk for CTS. The current study was designed to evaluate if these structural changes can be detected by HRS (high-resolution sonography). Additionally, the current study aimed to determine if changes are reversible after termination of dialysis. Fifty patients (98 hands) were included in the study. The study population was subdivided into three groups: patients without any history of renal disease (H, n=20), patients with long-term dialysis (D, n=10), and patients after renal transplantation (TX, n=20). None of the patients had any clinical symptoms for a median nerve compression syndrome. The CSA (cross-sectional area) of the median nerve was evaluated both 12cm proximally of the carpal tunnel inlet and directly at the carpal tunnel inlet. The ratio of those two values, the WFR (wrist forearm ratio), was calculated and analyzed. The CSA demonstrated significantly higher values in dialysis (D) and transplanted (TX) patients compared to the healthy (H) control group (P<0.001). No significant differences were detectable between the D and TX groups. Specifically, there was no significant difference in the WFR. Patients with chronic renal disease demonstrate significantly higher CSA values compared to their healthy counterparts. Termination of dialysis does not seem to reverse these morphological changes.

Matrix metalloproteinase genes on chromosome 11q22 and risk of carpal tunnel syndrome.

Involvement of tendons and/or connective tissue structures in the aetiology of idiopathic carpal tunnel syndrome (CTS) has been proposed. DNA sequence variants within genes encoding structural components of the collagen fibril, the basic structural unit of connective tissue, have been shown to associate with modulating CTS risk. The matrix metalloproteinases (MMPs) play an important role in connective tissue remodelling. Variants within the MMP10, MMP1, MMP3 and MMP12 gene cluster on chromosome 11q22 have been associated with connective tissue injuries. The aim of this study was to investigate whether variants within these MMP genes are associated with CTS. Ninety-seven, self-reported Coloured participants with a history of CTS release surgery and 131 appropriately matched controls were genotyped for MMP10 rs486055 (C/T), MMP1 rs1799750 (G/GG), MMP3 rs679620 (A/G) or MMP12 rs2276109 (A/G) variants. A Pearson's Chi-squared test or a Fisher's exact test was used to determine any significant differences between the genotype distributions or any other categorical data of the groups. An analysis of variance (ANOVA) was used to detect any significant differences between CTS and control groups for continuous data. There were no independent associations between any of the investigated MMP variants and CTS. There were also no significant differences in the relative distributions of the constructed MMP inferred haplotypes between CTS and CON groups. The MMP variants previously associated with other connective tissue injuries were not associated with CTS in this population. These findings do not exclude the possibility that other variants within this locus or other MMP genes are associated with CTS.

The effect of excess body mass on the risk of carpal tunnel syndrome: a meta-analysis of 58 studies.

We aimed to estimate the effects of overweight and obesity on carpal tunnel syndrome (CTS), and to assess whether sex modifies the associations. Literature searches were conducted in PubMed, Embase, Web of Science, Scopus, Google Scholar and ResearchGate databases from 1953 to February 2015. Fifty-eight studies consisting of 1,379,372 individuals qualified for a meta-analysis. We used a random-effects meta-analysis, assessed heterogeneity and publication bias, and performed sensitivity analyses. Overweight increased the risk of CTS or carpal tunnel release 1.5-fold (pooled confounder-adjusted odds ratio [OR] = 1.47, 95% CI 1.37-1.57, N = 1,279,546) and obesity twofold (adjusted OR = 2.02, 95% CI 1.92-2.13, N = 1,362,207). Each one-unit increase in body mass index increased the risk of CTS by 7.4% (adjusted OR = 1.074, 95% CI 1.071-1.077, N = 1,258,578). Overweight and obesity had stronger effects on carpal tunnel release than CTS. The associations did not differ between men and women, and they were independent of study design. Moreover, the associations were not due to bias or confounding. Excess body mass markedly increases the risk of CTS. As the prevalence of overweight and obesity is increasing globally, overweight-related CTS is expected to increase. Future studies should investigate whether a square-shaped wrist and exposure to physical workload factors potentiate the adverse effect of obesity on the median nerve.

Association between work-related biomechanical risk factors and the occurrence of carpal tunnel syndrome: an overview of systematic reviews and a meta-analysis of current research.

BackgroundOccupational risks for carpal tunnel syndrome (CTS) have been examined in various occupations, and several systematic reviews (SRs) have been published on this topic. There has been no critical appraisal or synthesis of the evidence in the SRs. The aims of this study are (1) to synthesise the observational evidence and evaluate the methodological quality of SRs that assess the effect of biomechanical risk factors on the development of CTS in workers, (2) to provide an update of current primary research on this association, (3) to assess a potential dose-response relationship.MethodsWe searched MEDLINE, EMBASE, CINAHL, the Cochrane Library and the reference lists of articles. The first step covered SRs (1998–2014), and the second step covered current primary studies (2011–2014). The methodological quality of the SRs was evaluated by using the AMSTAR-R tool; primary studies were assessed using a list of 20 items. A qualitative approach was used for synthesising evidence. In addition, we undertook a meta-analysis of the primary studies to determine risk ratios in the dose-response relationship.ResultsWe identified ten SRs that covered a total of 143 original studies. Seven primary studies met the criteria for inclusion, of which four provided longitudinal data. We found high quality of evidence for risk factors such as repetition, force and combined exposures. Moderate quality of evidence was observed for vibration, and low quality of evidence was found for wrist postures. An association between computer use and CTS could not be established. Recent primary studies supported the existence of a significant relationship between CTS and repetition, force and combined exposure. The meta-analysis of current research revealed a dose-response relationship between CTS and the American Conference of Governmental Industrial Hygienists’ (ACGIH) threshold limit value (TLV) for hand-activity level (HAL). Those between the action limit and TLV and above TLV had RR of 1.5 (95 % CI 1.02–2.31) and RR 2.0 (95 % CI 1.46–2.82), respectively.ConclusionsOccupational biomechanical factors play a substantial role in the causation of CTS. Data from current primary studies on dose-response suggest that the risk of CTS increases with the ACGIH TLV levels.Electronic supplementary materialThe online version of this article (doi:10.1186/s12891-015-0685-0) contains supplementary material, which is available to authorized users.

Prevalence of persistent median artery in carpal tunnel syndrome: sonographic assessment.

This study investigated the frequency of persistent median artery (PMA) in patients with carpal tunnel syndrome (CTS) and controls. A total of 84 CTS patient wrists, and 136 wrists of control subjects without CTS, were examined on ultrasonography (US) and color Doppler US (CDUS), and by electrophysiological evaluations. The frequency of PMA in CTS was evaluated. Of 84 CTS patient wrists, 2 (2.4%) had a PMA (both on the right side). Of 136 control wrists, 12 (9%) had a PMA, which was unilateral in eight (three right and five left), and bilateral in two, cases. There was no significant difference between the CTS patient and control groups with respect to the frequency of PMA (P>0.05). There was no significant difference between the CTS patient and control groups in the frequency of PMA. We suggest that an ipsilateral PMA does not increase the risk of CTS.

Anthropometric measurements as a screening test for carpal tunnel syndrome: receiver operating characteristic curves and accuracy.

To identify optimal cutoff values for body, hand, and wrist measurements in order to correctly identify individuals with carpal tunnel syndrome (CTS), using receiver operating characteristic (ROC) curves. We enrolled patients with CTS and control subjects at a 1:2 ratio, regardless of age and sex. The diagnosis of CTS was based on clinical findings and delayed distal conduction velocity of the median nerve. The anthropometric measurements included weight, height, waist circumference, hip circumferences, wrist depth/width, third digit length, and palm length/width. Obesity indicators and hand/wrist ratios were calculated. Area under the ROC curve (AUC), sensitivity, specificity, and likelihood ratios were calculated separately according to sex. To assess the role of multiple anthropometric measurements, we fit multivariable logistic regression models including age, wrist ratio, shape index, body mass index, and waist-to-hip ratio. The study group comprised 1,117 subjects (250 female patients and 474 female controls; 120 male patients and 273 male controls). In women, the accuracy of all anthropometric measures was low (AUC ≤0.64). In men, the accuracy of the hand ratio, shape index, and wrist-to-palm ratio was moderate (AUC = 0.75). The estimates from the multivariable models confirmed the well-known associations between the selected variables and the risk of CTS, but the use of multiple predictors did not dramatically improve the diagnostic performance observed for single anthropometric indexes. In clinical practice, the cutoff values for many anthropometric measurements have limited value as tools for the diagnosis of CTS.

Interleukin and growth factor gene variants and risk of carpal tunnel syndrome

Recent research has identified DNA sequence variants within genes encoding structural components of the collagen fibril, the basic structural unit of tendons, to modify the risk of carpal tunnel syndrome (CTS). Since the expression of these previously associated genes are regulated by cytokine and growth factor signalling pathways, the aim of this study was to determine whether variants within these cell signalling pathway genes, namely interleukin 1β (IL-1β), IL-6, interleukin 6 receptor (IL-6R) and vascular endothelial growth factor A(VEGFA), are also associated with CTS.One hundred and three self-reported Coloured participants, with a history of carpal tunnel release surgery (CTS) and 149 matched control participants (CON) without any reported history of CTS symptoms were genotyped for the functional IL-1β rs16944 (-511C/T), IL-6 rs1800795 (−174G/C), IL-6R rs2228145 (C/A) and VEGFA rs699947 (−2578C/A) variants. Only the IL-6R variant was significantly associated with CTS (p=0.005, OR=0.41, 95% CI 0.22–0.75). When the previously reported associated COL5A1 and BGN variants were included in the analysis, gene–gene interactions were also shown to significantly modulate the risk of CTS.In conclusion, the AA genotype of IL-6R rs2228145 was independently associated with reduced risk of CTS in a South African Coloured population. The IL-6R variant interacted with the previously reported COL5A1 and BGN variants to modulate CTS risk. This highlights that interleukin and growth factor gene variants should also be considered, in addition to the extracellular matrix proteins, for future research in determining the aetiology of CTS.

Associations analysis of GSTM1, T1 and P1 Ile105Val polymorphisms with carpal tunnel syndrome.

Oxidative stress was related with carpal tunnel syndrome (CTS). We aimed to clarify the associations between glutathione S-transferase (GST)M1, GSTT1 and GSTP1-Ile105Val polymorphisms and CTS. One hundred-forty patients with CTS and 97 healthy controls were enrolled in this study. Tinel and Phalen signs were noted as positive or negative. Functional and clinical status of patients was evaluated by the Boston Questionnaire. The intensity of hand and/or wrist pain was evaluated on 10cm visual analog scale (VAS). We applied the polymerase chain reaction (PCR) to determine the polymorphisms of the GSTM1 and GSTT1 and the PCR-restriction fragment length polymorphism method for detecting the GSTP1-Ile105Val polymorphism. The M1 null genotype was significantly higher in patients with CTS compared to healthy controls, and the M1 null genotype seemed to increase the risk of CTS approximately two-fold (P = 0.011; odds ratio (OR) = 1.98; 95% confidence interval (CI) 1.17-3.36). The M1 null, T1 present combined genotype was significantly higher in patients with CTS compared to healthy controls (P = 0.043); however, it seemed not to increase the risk of CTS (P = 0.14; OR = 0.62; 95% CI 0.33-1.76). We found significantly higher levels of the VAS, Boston Symptom Severity Scale and Phalen sign in patients with the Ile/Val or the Val/Val genotypes compared to those in patients with the Ile/Ile genotype (P = 0.003, 0.004 and 0.044, respectively). We proposed that genes involved in the protection from oxidative stress may influence the susceptibility, clinical and functional status of CTS. The GSTM1 null genotype may be related with the development of CTS, whereas the Val allele of GSTP1-Ile105Val polymorphism may be associated with worse functional and clinical status in CTS.

Chapter 22 - Occupational mononeuropathies in industry

Peripheral nerve injuries have the potential to cause significant disability and can be commonly associated with recreational and occupational activities. Acute nerve injuries are mainly related to violent trauma, while repeated mechanical trauma due to external forces or repetitive motions can produce chronic nerve compression injury. This chapter will present a narrative review of the existing evidence of the association between peripheral compressive nerve disorders and work-related risk factors. Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy in the general population and in working populations employed in manual repetitive and forceful activities. The work-relatedness of CTS is essentially based on epidemiologic evidence and the results of experimental studies showing the capability of repetitive wrist extreme postures, associated with hand-wrist forceful exertions, to increase the pressure inside the carpal tunnel and to compress the median nerve. Assembly industry, food processing and packaging, hand-arm vibrating tools, and jobs involving high-repetition, high-force tasks put workers at risk for CTS. Less strong evidence exists of the association between ulnar elbow neuropathy and manual tasks or repetitive stretch on squatting and peroneal nerve neuropathy at the fibular head. Very few reports are available about the association between occupation and other compressive peripheral nerve injuries.

Biomechanical risk factors for carpal tunnel syndrome: a pooled study of 2474 workers

BackgroundBetween 2001 and 2010, five research groups conducted coordinated prospective studies of carpal tunnel syndrome (CTS) incidence among US workers from various industries and collected detailed subject-level exposure information with...

A vertical mouse and ergonomic mouse pads alter wrist position but do not reduce carpal tunnel pressure in patients with carpal tunnel syndrome

Non-neutral wrist positions and external pressure leading to increased carpal tunnel pressure during computer use have been associated with a heightened risk of carpal tunnel syndrome (CTS). This study investigated whether commonly used ergonomic devices reduce carpal tunnel pressure in patients with CTS. Carpal tunnel pressure was measured in twenty-one patients with CTS before, during and after a computer mouse task using a standard mouse, a vertical mouse, a gel mouse pad and a gliding palm support. Carpal tunnel pressure increased while operating a computer mouse. Although the vertical mouse significantly reduced ulnar deviation and the gel mouse pad and gliding palm support decreased wrist extension, none of the ergonomic devices reduced carpal tunnel pressure. The findings of this study do therefore not endorse a strong recommendation for or against any of the ergonomic devices commonly recommended for patients with CTS. Selection of ergonomic devices remains dependent on personal preference.