Occurrence Of Carpal Tunnel Syndrome Research Articles

Risk factors for neck and upper extremity disorders among computer users and the effect of interventions: an overview of systematic reviews

ObjectivesTo summarise systematic reviews that 1) assessed the evidence for causal relationships between computer work and the occurrence of carpal tunnel syndrome (CTS) or neck and upper extremity musculoskeletal disorders...

Risk Factors for Neck and Upper Extremity Disorders among Computers Users and the Effect of Interventions: An Overview of Systematic Reviews

BackgroundTo summarize systematic reviews that 1) assessed the evidence for causal relationships between computer work and the occurrence of carpal tunnel syndrome (CTS) or upper extremity musculoskeletal disorders (UEMSDs), or 2) reported on intervention studies among computer users/or office workers.Methodology/Principal FindingsPubMed, Embase, CINAHL and Web of Science were searched for reviews published between 1999 and 2010. Additional publications were provided by content area experts. The primary author extracted all data using a purpose-built form, while two of the authors evaluated the quality of the reviews using recommended standard criteria from AMSTAR; disagreements were resolved by discussion. The quality of evidence syntheses in the included reviews was assessed qualitatively for each outcome and for the interventions.Altogether, 1,349 review titles were identified, 47 reviews were retrieved for full text relevance assessment, and 17 reviews were finally included as being relevant and of sufficient quality. The degrees of focus and rigorousness of these 17 reviews were highly variable. Three reviews on risk factors for carpal tunnel syndrome were rated moderate to high quality, 8 reviews on risk factors for UEMSDs ranged from low to moderate/high quality, and 6 reviews on intervention studies were of moderate to high quality. The quality of the evidence for computer use as a risk factor for CTS was insufficient, while the evidence for computer use and UEMSDs was moderate regarding pain complaints and limited for specific musculoskeletal disorders. From the reviews on intervention studies no strong evidence based recommendations could be given.Conclusions/SignificanceComputer use is associated with pain complaints, but it is still not very clear if this association is causal. The evidence for specific disorders or diseases is limited. No effective interventions have yet been documented.

Clinical characteristics and electrodiagnostic features in patients with carpal tunnel syndrome, double crush syndrome, and cervical radiculopathy

Similar unilateral neck and upper limb symptoms are often due to various entrapment neuropathies; carpal tunnel syndrome (CTS) and cervical radiculopathy (CR) are common causes among them. Therefore, we investigated the clinical characteristics and electrodiagnostic features of patients with carpal tunnel syndrome, cervical radiculopathy, and both conditions, called double crush syndrome (DCS). The medical records and electrodiagnostic reports of 866 patients with suspected CTS and CR visited a tertiary-care hospital were retrospectively analyzed. After excluding 101 patients with confounding conditions, 151 (20%) patients were diagnosed to have sole cases of CTS; 362 (47%) patients were diagnosed to have sole cases of CR; 198 (26%) patients were diagnosed to have DCS, while 54 (7%) patients had mere symptoms. Sole cases of CR had the highest incidences of neck pain, upper back pain, wrist and hand weakness. Female patients had the highest incidences of all the diseases in their sixth decade. Male patients had comparably distinguished high occurrence of all the diseases in their fifth to sixth decades. Although comparison of nerve conduction studies between patients with mere symptoms and patients with sole cases of CTS or DCS showed statistical differences, comparison between the latter two revealed no difference. We found most patients referred for electrodiagnostic studies had cervical radiculopathy. High concomitant occurrence of CTS and CR suggests cautious evaluation of patients with upper limb symptoms is important, because the management of these conditions is quite different.

Familial primary carpal tunnel syndrome with possible skipped generation

Carpal tunnel syndrome, an entrapment neuropathy of the median nerve, is rarely seen in childhood. Familial carpal tunnel syndrome, an even more exceptional entity, is frequently associated with inherited systemic disorders. Rarely it can be presented as a primary familial form with Mendelian autosomal dominant inheritance. We report the occurrence of carpal tunnel syndrome in two generations of a family in which the index case was a 6-year-old boy with bilateral hand pain and paresthesias. Our report demonstrates an interesting inheritance pattern of carpal tunnel syndrome in a family transmitted by an autosomal dominant gene with variable expressivity and reduced penetrance. To our knowledge, it is the first report of familial bilateral carpal tunnel syndrome in a family with possible skipped generation.

Associations between work-related factors and the carpal tunnel syndrome—a systematic review

The aim of this study was to make a quantitative assessment of the exposure-response relationships between work-related physical and psychosocial factors and the occurrence of carpal tunnel syndrome (CTS) in occupational populations. A systematic review of the literature was conducted on the associations of type of work, physical load factors, and psychosocial aspects at work to the occurrence of CTS. The associations between work factors and CTS were expressed in quantitative measures, namely, odds ratios (OR) or relative risks. Jobs with the highest risk of CTS included work in the meat- and fish-processing industry, forestry work with chain saws, and electronic assembly work (OR 76.5, 21.3, and 11.4, respectively). The occurrence of CTS was associated with high levels of hand-arm vibration, prolonged work with a flexed or extended wrist, high requirements for hand force, high repetitiveness, and their combination. No association was found between any psychosocial risk factor and CTS. Contradictory findings were reported for associations between computer work and CTS. This review provides consistent indications that CTS is associated with an average hand force requirement of >4 kg, repetitiveness at work (cycle time 50% of cycle time performing the same movements), and a daily 8-hour energy-equivalent frequency-weighted acceleration of 3.9 m/s2.

Occurrence of myofascial pain in patients with possible carpal tunnel syndrome – A single-blinded study

Background There exits some similarity between symptoms of carpal tunnel syndrome (CTS) and myofascial pain related to trigger points (TPs) in the infraspinatus muscle. Aim The aim was to examine what proportion of patients referred with a clinical suspicion of CTS had myofascial pain in the infraspinatus muscles and how their occurrence was related to the outcome of nerve conduction studies (NCS). Methods We examined the occurrence of CTS and of TPs in infraspinatus muscles in a cohort of patients suspected for CTS and referred to the Department of Clinical Neurophysiology, Aarhus University Hospital from October 2003 to February 2004. Patients underwent electrodiagnostic studies of the median and ulnar nerves. Additional tests were performed if necessary. Patients were examined for TPs by a blinded examiner immediately after NCS. Results We included 335 patients (202 females; 133 males, mean age 46). Two hundred one patients (60%) had abnormal NCS indicating CTS. Fifteen patients (4%) had other electrodiagnostic abnormalities. One hundred nineteen patients (36%) had normal NCS. Forty nine percent (58 out of 119) of the subjects with normal NCS had TPs in the infraspinatus muscles whereas only 26% (53 out of 201) of the patients with abnormal NCS indicating CTS had TPs. Likewise, 26% (4 out of 15) of the patients with other electrodiagnostic abnormalities had TPs. Conclusions Approximately one third of patients referred with a clinical suspicion of CTS had TPs in the infraspinatus muscles. This occurrence was higher in the group with normal NCS than in the group with abnormal NCS indicating CTS. When CTS is suspected clinically, physicians must be aware of TPs in the infraspinatus muscles as a possible cause of the symptoms; thus, NCS are important in these patients.

Carpal Tunnel Syndrome Associated with the Use of Aromatase Inhibitors in Breast Cancer

Aromatase inhibitors (AI) inhibit peripheral conversion of androgens to estradiol and are commonly used as hormonal therapy for postmenopausal women with hormone receptor–positive breast cancer in the metastatic and adjuvant settings. Joint-related symptoms, however, are seen in a significant proportion of patients. Carpal tunnel syndrome (CTS) is a common nerve entrapment disorder affecting the median nerve. We describe 6 patients with newly diagnosed CTS after initiation of adjuvant AI therapy. Aromatase inhibitors were discontinued in several patients secondary to this toxicity with some switching to tamoxifen and most subsequently experiencing relief of their symptoms. Potential pathophysiologic roles of hormonal manipulation with AIs and other risk factors that might contribute to CTS are discussed. Aromatase inhibitors might accentuate the occurrence of CTS and potentially other nerve entrapment syndromes, and a more systematic approach should be used to better understand the clinical significance and incidence of these symptoms.

Carpal tunnel syndrome and ulnar neuropathy at the elbow in floor cleaners

Objective To determine the occurrence of carpal tunnel syndrome (CTS) and ulnar neuropathy at the elbow (UNE) in a cohort of floor cleaners and to check differences between workers with and without CTS. Methods All female floor cleaners of three major hospitals in Tuscany (Italy) were contacted. Clinical and electrophysiological severity of CTS and UNE were evaluated with standardized scales and symptoms were assessed with the self-administered Boston Questionnaire (BQ); demographic and non-occupational factors and durations of current and previous occupations were recorded. Univariate analysis of risk factors was performed in workers with and without CTS. Logistic regression was used to evaluate the capacity of independent variables to predict CTS. Results Out of a total of 179 cleaners, 145 (81%)—mean age 39.6 years (20–64 years)—were enrolled in the study; 70 (48%) had CTS (diagnosis based on clinical and electrophysiological findings). BQ symptom and hand function scores were anomalous in 108 (74%) and 84 (58%) subjects, respectively. UNE was detected in 7/103 women. Univariate analysis showed that cleaners with CTS were older, had greater BMI and longer exposure to cleaning with previous employers than those without CTS. In the logistic regression, the only predictor of CTS was cleaning with previous employers (O.R. 12.1, 95% CI 3–49.9). Conclusions These results indicate a high occurrence of CTS in floor cleaners; UNE is less frequent than CTS, presumably due to repetitive movements that stress wrists more than elbows. The only predictive factor of CTS was cleaning as an occupation with previous employers. Therefore, the actual risk factor for CTS could not be cleaning per se, but how this job is performed.

A longitudinal study of predictors of research-defined carpal tunnel syndrome in industrial workers: findings at 17 years

In 1984, we initiated a prospective study of factors associated with research-defined carpal tunnel syndrome (CTS) in 471 industrial workers. Medical history, lifestyle factors and job tasks were assessed by questionnaire and CTS case status was based on both symptoms and electrophysiologic findings. Participants were re-examined in 1989, 1994 to 1995 and 2001 to 2002. This study reports both baseline and aggregated risk factors associated with increased risk of CTS by 2001 to 2002 for 166 participants successfully re-examined after 17 years. In analyses of baseline risk factors, fewer repetitive tasks at work, female gender and greater relative weight were associated with any occurrence of CTS during follow-up. In analyses of aggregate risk factor scores through 1994 to 1995, only greater relative weight and female gender were associated with CTS in 2001 to 2002. Although obesity and gender are consistent predictors of CTS, workplace demands appear to bear an uncertain relationship to CTS. These findings are also discussed in relation to the possible differences between research-defined CTS and medically referred CTS.

Carpal tunnel syndrome: a question of hand and wrist configurations?

This study investigated whether there is an association between hand and wrist configurations and the occurrence of carpal tunnel syndrome. The external hand and wrist dimensions of 50 subjects with carpal tunnel syndrome and 50 healthy volunteers were measured and compared. In addition carpal tunnel depth and width were determined with ultrasound. Our results showed that the hand length was significantly higher in the control group (hand length, 19.0; SD, 1.0 cm: patients’ hand length, 18.2; SD, 1.1 cm) and the palm width was significantly greater in the patients’ group (palm width, 9.1; SD, 0.7 cm: controls palm width, 8.6; SD, 0.6 cm). Carpal tunnel syndrome patients had a squarer wrist (wrist ratio, 0.72; SD, 0.1) and carpal tunnel (carpal tunnel ratio, 0.48; SD, 0.1) than the controls (wrist ratio, 0.68; SD, 0.1; carpal tunnel ratio, 0.42; SD, 0.1). These findings indicate that the anatomy of the hand, wrist and carpal tunnel may predispose to carpal tunnel syndrome.

Ultrapure dialysis fluid: Improving conventional and daily dialysis

Dialysis fluid of standard quality contains a certain amount of bacteria and endotoxin. This has been considered acceptable because the dialysis membrane was believed to be a protective barrier to blood. However, improved methods for detection of cellular activation have demonstrated that bacterial products in the dialysate may stimulate monocytes to produce cytokines with most dialysis membranes. Ultrapure dialysis fluid is practically free from bacteria and endotoxin (< 0.1 CFU/mL and < 0.03 EU/mL) and can be prepared from standard-quality dialysis fluid using a single step of controlled ultrafiltration. The European guidelines for hemodialysis (HD) set the use of ultrapure dialysis fluid as the goal for all dialysis modalities. Several clinical studies report improved inflammatory status in HD patients when ultrapure dialysis fluid is used, compared with standard-quality dialysate. The benefits include less frequent occurrence of carpal tunnel syndrome, lower C-reactive protein values, reduced need for erythropoietin, better nutritional status, and even better preservation of residual renal function. For patients on daily dialysis, dialysate quality is especially important because such patients are often treated at home where quality control of incoming water may be less rigorous, and increased treatment frequency leads to exposure to larger volumes of dialysis fluid than with conventional dialysis. The use of ultrapure dialysis fluid together with low-complement-activating membranes maximizes the biocompatibility of a dialysis treatment, a goal of treatment, although there is a lack of evidence to date supporting a beneficial effect on mortality. From a physiologic point of view the reduced inflammatory stimulus that can be achieved with ultrapure dialysis fluid is highly desirable. In addition, achieving ultrapure dialysis fluid is realistic, because today it can be practically and economically prepared using modern equipment and applying appropriate microbiologic surveillance techniques.

Carpal tunnel syndrome due to keyboarding and mouse tasks: a review

So far, many different studies have examined possible implications of typing related posture and activity on carpal tunnel syndrome (CTS) incidence. Although they tend to present the findings as very apparent ones, assessing the complex relationships between the different causal factors implicated in keyboarding and in the usage of pointing devices, on the one hand, and work related upper extremity disorders (WRUED), especially CTS, on the other hand, is problematic. The aim of this review paper is to outline relevant information about CTS risk factors present in data entry task and their implications, with a special emphasis on different extreme postures determined by conventional and alternate keyboards, pointing devices and their role in the development of CTS. Secondly, a comparison of several keyboards with respect to design of keyswitch to reduce force and its effect on carpal tunnel pressure (CTP) is provided. This review critically considers the factors implicated in the occurrence of CTS due to computer work, analysing the determining factors from a well-considered perspective instead of considering them separate entities. Many “ergonomic” keyboards change the musculoskeletal region exposed to risk, instead of eliminating hazardous postures. The ergonomic assessment of new devices should precede their introduction and not follow it. Future research should be directed to establish a comprehensive understanding of what combinations of trigger factors should be eliminated or modified, to assess the impact of workstation redesign and to uncover the interrelationships between different factors that contribute to the development of CTS. Relevance to industry Because of the trend in the occurrence of the Repetitive Strain Injuries (RSI), especially CTS with keyboard and mouse use, the assessment of all the causal factors, as well as the interrelationship between them in the development process of CTS in data entry tasks will lead to a decrease in medical and non-medical costs. Information could be used for job redesign in order to increase ergonomic qualities and productivity.

Symptoms and neurophysiological picture of carpal tunnel syndrome in pregnancy

Objective: To evaluate the incidence of carpal tunnel syndrome (CTS) in pregnancy through a validated and multiperspective assessment of CTS. Methods: During 2000, the Italian CTS study group focussed on the occurrence of CTS in women during the final stages of pregnancy, enrolled in 7 Italian centers. In addition to the physician-centered and neurophysiologic traditional evaluations, we used a validated patient-oriented measurement to obtain more comprehensive and consistent data for severity of symptoms and functional impairment. Results: In our study, CTS was clinically diagnosed in more than half of women (62%). Neurophysiological evaluation provided diagnosis of CTS in around half of women (43% were positive in one hand at least). Our study provides evidence, reported here for the first time, of a correlation between edema and neurophysiological picture. Similarly, our study provides a correlation between validated patient-oriented measurement and edema. Moreover, a significant correlation between a negative trend (subjectively assessed) and smoking and alcohol consumption was observed. Conclusions: Our observations confirm that the edema of the tissues in the carpal tunnel could induce a mechanical compression of the nerve. Moreover, our data suggest that smoking and alcohol consumption have a negative role in the evolution of the syndrome probably due to impairment of the microcirculation.

A fuzzy linguistic model for the prediction of carpal tunnel syndrome risks in an occupational environment

This research presents the development and evaluation of a fuzzy linguistic model designated to predict the risk of carpal tunnel syndrome (CTS) in an occupational setting. CTS has become one of the largest problems facing ergonomists and the medical community because it is developing in epidemic proportions within the occupational environment. In addition, practitioners are interested in identifying accurate methods for evaluating the risk of CTS in an occupational setting. It is hypothesized that many factors impact an individual's likelihood of developing CTS and the eventual development of CTS. This disparity in the occurrence of CTS for workers with similar backgrounds and work activities has confused researchers and has been a stumbling block in the development of a model for widespread use in evaluating the development of CTS. Thus this research is an attempt to develop a method that can be used to predict the likelihood of CTS risk in a variety of environments. The intent is that this model will be applied eventually in an occupational setting, thus model development was focused on a method that provided a usable interface and the desired system inputs can also be obtained without the benefit of a medical practitioner. The methodology involves knowledge acquisition to identify and categorize a holistic set of risk factors that include task-related, personal, and organizational categories. The determination of relative factor importance was accomplished using analytic hierarchy processing (AHP) analysis. Finally a mathematical representation of the CTS risk was accomplished by utilizing fuzzy set theory in order to quantify linguistic input parameters. An evaluation of the model including determination of sensitivity and specificity is conducted and the results of the model indicate that the results are fairly accurate and this method has the potential for widespread use. A significant aspect of this research is the comparison of this technique to other methods for assessing presence of CTS. The results of this evaluation technique are compared with more traditional methods for assessing the presence of CTS.

Role of physical load factors in carpal tunnel syndrome.

Epidemiologic and experimental studies were reviewed to assess the role of postural factors, high handgrip and pinch forces, repetitive hand and wrist movements, external pressure, and vibration in the occurrence of carpal tunnel syndrome (CTS). Forceful repetitive work, vibration, and extreme wrist postures have been associated with CTS in several epidemiologic studies. Experimental studies have shown that certain forearm, wrist, and finger postures, even moderate hand loads and external pressure on the palm, can increase carpal tunnel pressure (CTP) at least temporarily to levels at which nerve viability is threatened. It is concluded that while more research is needed, there is sufficient information to suggest that reducing the duration, frequency or intensity of exposure to forceful repetitive work, extreme wrist postures and vibration is likely to result in a reduction of the incidence or severity of CTS in working populations.

The Advanced Glycation Endproduct, Pentosidine, in the Carpal Ligament in Patients with Carpal Tunnel Syndrome Undergoing Hemodialysis: Comparison with Idiopathic Carpal Tunnel Syndrome

Background/Aims: Carpal tunnel syndrome (CTS) is a major complication that occurs in the musculoskeletal system in patients on long-term hemodialysis (HD). Pentosidine is an advanced glycation endproduct (AGE) and there is evidence that shows AGEs contribute to the pathogenesis of the complications in patients undergoing HD. The aim of this study is to investigate whether pentosidine accumulates in the carpal ligament in patients undergoing HD with CTS in comparison with idiopathic CTS. Methods: Carpal ligaments and skin were obtained during surgery from 28 patients with CTS undergoing HD and 13 patients with idiopathic CTS (ID CTS). Pentosidine was measured by HPLC after hydrolysis of the samples, and amyloid deposits in the samples of HD CTS were examined histologically. Results: Pentosidine levels in ligament and skin were significantly higher in HD CTS than ID CTS. On the other hand, there was no difference in pyridinoline which is a physical cross-link between HD and ID CTS. Amyloid deposits were observed in 14 ligament samples, whereas there was none in 14 other samples. There was no significant difference in pentosidine and pyridinoline in ligament, pentosidine in skin, duration of HD and serum β₂-microglobulin between the amyloid+ group and the amyloid– group. Conclusion: A greater concentration of pentosidine in the carpal ligament in HD patients compared with idiopathic patients suggests that an accumulation of AGEs contributes to one of the pathologies of occurrence of CTS in patients undergoing HD.

Crutch handle design: Effect on palmar loads during ambulation

Objective: To compare loads, load distributions, pressures, and areas of weight-bearing on the palm for forearm crutches with cylindrical and wide handles during ambulation to determine if one handle type produced greater loads on the carpal tunnel region. Design: Single-group repeated measures of normal adults; descriptive study of patients who were long-term crutch users. Data were collected from six palmar regions using an F-Scan system. Setting: Center for neuromuscular disorders in a hospital. Participants: Thirty normal volunteers and 6 patients. Main Outcome Measure: Differences in loads for the palmar regions between the two handles, particularly the carpal tunnel region. Results: For the normal adults, significantly greater loads were found in two distal regions for the cylindrical handle and in one proximal region for the wide handle. Distribution of weight-bearing loads showed a similar pattern for both handles with the palm's proximal and distal radial sides having the greatest loads and the carpal tunnel region having the third highest load. The area of weight-bearing was significantly greater for the wide handle than for the cylindrical. Conclusions: Cylindrical and wide crutch handles have similar load distributions, making it impossible to recommend one type over the other to reduce the occurrence of carpal tunnel syndrome. The wide handle distributes the loads over a greater surface area, producing less focal pressure.

Incidence of bilateral symptoms in carpal tunnel syndrome

We prospectively studied 266 hands in 133 patients with carpal tunnel syndrome (CTS) in order to evaluate: the incidence of bilateral CTS symptoms; correlation between severity, duration of symptoms and bilateral occurrence of CTS; agreement of clinical and neurophysiological findings; and the neurophysiological findings in asymptomatic hands in unilateral CTS. The incidence of bilateral clinical CTS in our population was 87%. Neurophysiological impairment of median nerve was observed in about half of the asymptomatic hands. Follow-up of patients with unilateral CTS showed that contralateral symptoms developed in most cases. We found a significant positive correlation of bilateral CTS with the duration of symptoms, whereas there was no correlation with the severity of symptoms. Our data suggest that bilateral impairment of median nerve is the rule in patients with CTS and probably it has been underestimated in previous studies.

Carpal Tunnel Syndrome (CTS) on the Web

Abstract The occurrence of carpal tunnel syndrome (CTS) and other overuse syndromes has been on the increase with the advent of computer keyboards. Musicians, assembly-line workers, and others can suffer from this condition, thereby generating a widespread demand for information on diagnosis, treatment, and prevention. Many resources about CTS and repetitive strain injury (RSI) exist on the Internet, but they appear in many formats and under a broad spectrum of subjects—from neurology and rheumatology to ergonomics and occupational hazards. In this discussion, various types of information providers are profiled with sample Web sites described in each category. The categories include traditional medical literature sources, health information interfaces or filters, and other CTS information providers, which include; government agencies, medical associations, academic institutions, clinical services, companies selling products, and personal pages.

A fuzzy linguistic model for the prediction of carpal tunnel syndrome risks in an occupational environment

This research presents the development and evaluation of a fuzzy linguistic model designated to predict the risk of carpal tunnel syndrome (CTS) in an occupational setting. CTS has become one of the largest problems facing ergonomists and the medical community because it is developing in epidemic proportions within the occupational environment. In addition, practitioners are interested in identifying accurate methods for evaluating the risk of CTS in an occupational setting. It is hypothesized that many factors impact an individual's likelihood of developing CTS and the eventual development of CTS. This disparity in the occurrence of CTS for workers with similar backgrounds and work activities has confused researchers and has been a stumbling block in the development of a model for widespread use in evaluating the development of CTS. Thus this research is an attempt to develop a method that can be used to predict the likelihood of CTS risk in a variety of environments. The intent is that this model will be applied eventually in an occupational setting, thus model development was focused on a method that provided a usable interface and the desired system inputs can also be obtained without the benefit of a medical practitioner. The methodology involves knowledge acquisition to identify and categorize a holistic set of risk factors that include task-related, personal, and organizational categories. The determination of relative factor importance was accomplished using analytic hierarchy processing (AHP) analysis. Finally a mathematical representation of the CTS risk was accomplished by utilizing fuzzy set theory in order to quantify linguistic input parameters. An evaluation of the model including determination of sensitivity and specificity is conducted and the results of the model indicate that the results are fairly accurate and this method has the potential for widespread use. A significant aspect of this research is the comparison of this technique to other methods for assessing presence of CTS. The results of this evaluation technique are compared with more traditional methods for assessing the presence of CTS.