The relationship of obesity, age, and carpal tunnel syndrome: more complex than was thought?

Predictors of pain intensity in carpal tunnel syndrome: Development and validation of a model

OBJECTIVE

Pain often accompanies carpal tunnel syndrome and affects patients' health-related quality of life. The aim was to develop and validate a predictive model for the pain intensity of carpal tunnel syndrome using demographic, clinical, electrophysiological, and ultrasound findings.

METHODS

We conducted a secondary analysis of data from a large sample of patients (May 2017 to December 2022) with carpal tunnel syndrome. A total of 520 (53.0 %) mild, 276 (28.1 %) moderate, and 186 (18.9 %) severe syndromes were included in the complete data set of 982 hands (61.1 % female). The mean age was 57.8 (10.7) years and the median duration [interquartile range] of the symptoms was 4 [2,10] months. A regression model was developed and validated to predict pain intensity on a numerical rating scale using a tree-based machine learning algorithm.

RESULTS

The validation of the regression model showed good performance with a root mean squared error, R-squared, and mean absolute error of 1.35, 0.42, and 1.05, respectively. Overall, the top significant predictors of pain intensity were compound motor nerve action potential latency, nocturnal pain, and thenar weakness. These were followed by the cross-sectional area of the median nerve, sensory nerve action potential, bowing of the flexor retinaculum, disease duration, and body mass index. We did not find strong associations between the median nerve transcarpal latency, age, sex, and diabetes with the pain intensity of carpal tunnel syndrome.

CONCLUSION

Our model showed good performance in predicting the subjective pain intensity of carpal tunnel syndrome, even in the context of non-linear relations.

Khachatryan L, Mohammadian-Hafshejani A. Investigating the association between diabetes and carpal tunnel syndrome: A systematic review and meta-analysis approach

INTRODUCTION

In recent years, several studies have reported on the relationship between diabetes and carpal tunnel syndrome (CTS). However, due to their contradictory results, a systematic review and meta-analysis were conducted to investigate this subject.

METHODS

This study is a systematic review and meta-analysis of studies published in ISI Web of Science, Scopus, PubMed, Cochrane, Google Scholar, and Embase databases. Heterogeneity in the studies included in the meta-analysis was evaluated using statistical tests such as the Chi-square test, I2, and forest plots. Publication bias was assessed using Begg's and Egger's tests.

RESULTS

This investigation analyzed data from 42 studies conducted between 1985 and 2022, with a total of 3,377,816 participants. The meta-analysis demonstrated that the odds ratio (OR) of CTS in participants with a history of diabetes compared to those without was 1.90 (95% CI: 1.64-2.21; P-value < 0.001). Given that publication bias was observed in this study (Begg's test P-value = 0.01), the modified OR was calculated with consideration of missed studies, which was 1.68 (95% CI: 1.45-1.94; P-value < 0.001).

CONCLUSION

The results of this study suggest that diabetic patients have 90% higher odds of developing CTS compared to non-diabetic individuals, which is statistically significant.

Relationship between Gravidity, Parity, and Neurophysiological Features in Carpal Tunnel Syndrome (CTS) Patients with a History of Pregnancy

BACKGROUND

It is not yet clear if gravidity and parity have any relationships with the electrodiagnostic parameters of carpal tunnel syndrome (CTS).

OBJECTIVE

To determine whether there is a relationship between electrodiagnostic findings, gravidity, and parity number in CTS.

MATERIALS AND METHODS

Female patients over 18 years of age with CTS were included in this retrospective cohort study. The gravidity/parity number, median nerve compound muscle action potential (CMAP), and compound nerve action potential (CNAP) of the patients were analyzed. The two subgroups of the Boston carpal tunnel syndrome questionnaire (BCTSQ): The Symptom Severity Scale (SSS) and Functional Severity Scale (FSS) were applied to the patients. CTS patients were divided into two groups aged at first pregnancy ≤20 years and >20 years.

RESULTS

One hundred and eight CTS extremities (seven right-sided CTS, three left-sided CTS, 49 bilateral CTS) of 59 patients were included. The median (interquartile range: 25%-75%) number of gravidity, parity, and abortion were 3 (2-5), 3 (2-4), and 0 (0-0), respectively. Right-sided CTS patients at the age of first pregnancy ≤20 years had higher BCTSQ-SSS/FSS scores and median nerve CMAP latency compared to patients at the age of first pregnancy >20 years (P = 0.029 for SSS; P = 0.042 for FSS; and P = 0.041 for CMAP latency). A negative correlation was found between the gravidity/parity numbers and median nerve CNAP/CMAP amplitudes (P = 0.028/0.031, r = -0.293/-0.289 for CNAP amplitude; and P = 0.006/0.035, r = -0.363/-0.283 for CMAP amplitude).

CONCLUSION

Neurophysiological findings worsen as the number of gravidity and parity increase. Electrodiagnostic and clinical features of CTS may be worsening in females below 20 years at first pregnancy.

[Analysis of the echographic parameters described in the study of carpal tunnel syndrome: A systematic review]

Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy; the diagnosis is established by electrodiagnostic tests with until 34% of false positives/negatives. We present the following systematic review which objective is to analyze the most recent literature related to the ultrasound parameters described to study CTS. We selected studies that evaluated ultrasound parameters in patients with clinical suspicion following the Cochrane manual's recommendations. We include systematic reviews, meta-analyses, case-control studies and diagnostic tests, evaluating retrospective studies and bibliographic reviews with proper methodological quality. Articles published between 2005 and 2019. We included eight articles (two systematic reviews/meta-analyses, two case-control studies, one diagnostic test study, two literature reviews, and one retrospective). The parameters analyzed were cross-sectional area, wrist-forearm index, entry-exit index, thinning range, palmar bowing of the flexor retinaculum, and vascularity/mobility. Current evidence allows us to affirm that ultrasound is useful in screening for CTS.

Potential Relationships between the Median Nerve Cross-Sectional Area and Physical Characteristics in Unilateral Symptomatic Carpal Tunnel Syndrome Patients

Background: The present study investigated the relationships between the median nerve cross-sectional area (CSA) and physical characteristics in patients with unilateral symptomatic carpal tunnel syndrome (CTS). Methods: Height, weight, body mass index (BMI), disease duration, results of electrodiagnostic testing (EDX), and median nerve CSA at the level of the wrist crease were recorded in 81 patients with CTS who presented with symptoms on only one side. Correlation coefficients between median nerve CSA and physical characteristics, disease duration, and results of EDX were analyzed. Results: Median nerve CSA at the wrist crease (mm2) was significantly larger on the symptomatic side (14.1 ± 3.8) than on the asymptomatic side (11.5 ± 2.9). Median nerve CSA correlated with body weight (correlation coefficient = 0.39) and BMI (correlation coefficient = 0.44) on the asymptomatic side, but not on the symptomatic side. These correlations were slightly stronger in females (correlation coefficient = 0.46) than in males (correlation coefficient = 0.40). No correlations between median nerve CSA and disease duration and the results of EDX were observed in both sides. Conclusions: In patients with unilateral symptomatic CTS, median nerve CSA correlated with BMI only on the asymptomatic side. The present results suggest that the relationship between median nerve CSA and BMI in CTS is significant until symptom onset but may be masked by edema and pseudoneuroma after its onset. A higher BMI is associated with a larger CSA of the median nerve, which may be a risk factor for the development of CTS.

How to Differentiate Pronator Syndrome from Carpal Tunnel Syndrome: A Comprehensive Clinical Comparison

The diagnostic process that allows pronator syndrome to be differentiated reliably from carpal tunnel syndrome remains a challenge for clinicians, as evidenced by the most common cause of pronator syndrome misdiagnosis: carpal tunnel syndrome. Pronator syndrome can be caused by compression of the median nerve as it passes through the anatomical structures of the forearm, while carpal tunnel syndrome refers to one particular topographic area within which compression occurs, the carpal tunnel. The present narrative review is a complex clinical comparison of the two syndromes with their anatomical backgrounds involving topographical relationships, morphology, clinical picture, differential diagnosis, and therapeutic options. It discusses the most frequently used diagnostic techniques and their correct interpretations. Its main goal is to provide an up-to-date picture of the current understanding of the disease processes and their etiologies, to establish an appropriate diagnosis, and introduce relevant treatment benefiting the patient.

Boston Carpal Tunnel Questionnaire and Severity of Carpal Tunnel Syndrome

OBJECTIVES

Carpal tunnel syndrome (CTS) is a common compressive neuropathy linked to disability in severe cases. Tools capable of distinguishing the severity spectrum median nerve entrapment in clinical practice are desirable.

METHODS

This cross-sectional study included 58 CTS patients assisted in a Brazilian neurologic clinic. Participants were naive of surgical interventions and answered to Boston Carpal Tunnel Questionnaire (BCTQ). CTS was classified as mild, moderate, and severe according to electrodiagnostic testing.

RESULTS

There was no significant difference in BCTQ scores across the severity spectrum of median nerve entrapment, not even comparing mild cases with the group moderate/severe. Mild cases were younger (mean ± SD: 46.5 ± 9.2 years) than severe ones (60.0 ± 13.5, P = 0.04) and the group moderate/severe (55.5 ± 14.5, P = 0.01).

CONCLUSIONS

Results suggest that BCTQ is not adequate to assess the interpatient severity of median nerve entrapment on clinical practice.

A Systematic Review of the Outcomes of Carpal Ligament Release in Severe Carpal Tunnel Syndrome

PURPOSE

Indications for surgical treatment of severe carpal tunnel syndrome (CTS) are controversial. The aim of this study was to review the outcomes reported in the literature of carpal tunnel release in patients with severe CTS.

METHODS

A systematic review of the outcomes of carpal tunnel release in patients with severe CTS was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Outcome measures included change in symptoms, sensation (2-point discrimination, light touch), thenar atrophy, strength (power and pinch grip), electrophysiology, median nerve morphology, and patient-reported outcome measures. Outcomes are reported by ranges of the percentage of patients/hands improved in the included studies.

RESULTS

Thirty-eight papers were selected, representing 2,531 patients and 2,712 hands. Demographic information on age and sex were available for a total of 1,542 patients. Mean age ranged from 49.8 to 83 years and 72% were female. All studies that assessed patient-reported outcome measures before and after surgery reported significant improvements. Complete resolution of paresthesia occurred in 55%-98% of hands across different studies. Resolution of numbness occurred in between 39% and 94% of hands. Pain completely resolved in 64%-100% and weakness in 60%-75% of hands. Two-point discrimination and light touch improved postoperatively. Power grip, key, tripod, index-thumb pulp pinch, and thumb opposition increased. Motor and sensory amplitudes, distal motor latencies, and sensory conduction velocities improved. Patient-reported outcomes indicated symptomatic improvement and reduced disability.

CONCLUSIONS

Symptomatic improvement following carpal tunnel release in patients with severe CTS can occur. Patients should be counseled about the unpredictability of the outcomes and factors that might affect outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Carpal Tunnel Syndrome in Diabetes Mellitus

The aim of the present brief review was to discuss carpal tunnel syndrome (CTS) in diabetes mellitus (DM). Generally, CTS is more common in DM, especially in subjects with coexisting diabetic polyneuropathy (DPN) and/or long DM duration. There is no agreement if it is more frequent in type 1 or type 2 DM. The precise underlying mechanisms are not entirely clear but appear to involve hyperglycaemia-induced median nerve oedema, increased sensitivity to exogenous trauma and nerve myelin ischaemia and axonal degeneration. More recently, increased vascular endothelial growth factor (VEGF) and advanced glycation endproducts (AGEs) appear to also play an important role. Median nerve conduction study remains the cornerstone of CTS diagnosis in DM, being more sensitive than clinical examination. CTS can be treated medically or surgically. The latter appears now to be equally effective in subjects with vs. without DM in terms of recurrence rates and quality of life.

Carpal tunnel syndrome in patients with arteriovenous fistula for haemodialysis: A narrative review of the current literature

The ideal choice of vascular access in patients requiring haemodialysis is an arteriovenous fistula. However, an important often under-reported complication encountered at follow-up is symptoms of tingling or numbness in the hand. This may represent carpal tunnel syndrome, impairment of the median nerve as it traverses through the carpal tunnel at the wrist by focal compression of this nerve. Contributory factors in the presence of an arteriovenous fistula may include venous hypertension and varying steal syndrome phenomena provoking micro-ischaemia. Studies that investigated the evolution of carpal tunnel syndrome in haemodialysis patients with an arteriovenous fistula revealed that the frequency of carpal tunnel syndrome associated with an arteriovenous fistula on haemodialysis ranged from 10.4% to 42.6%. An association between duration of haemodialysis with arteriovenous fistula and carpal tunnel syndrome development was also observed. Surgical release of carpal tunnel provided complete relief of paraesthesia in all treated patients in the examined, demonstrating an alleviation of symptoms and improved function of hand and quality of life in patients with an arteriovenous fistula. However, the aetiology and risk factors for development of carpal tunnel syndrome remain unclear and further studies should attempt to elucidate the pathophysiology of this occurrence in the presence of arteriovenous fistulas.

Obesity, Type 2 Diabetes, and the Risk of Carpal Tunnel Syndrome: A Two-Sample Mendelian Randomization Study

Some previous observational studies have reported an increased risk of carpal tunnel syndrome (CTS) in patients with obesity or type 2 diabetes (T2D), which was however, not observed in some other studies. In this study we performed a two-sample Mendelian randomization to assess the causal effect of obesity, T2D on the risk of CTS. Single nucleotide polymorphisms associated with the body mass index (BMI) and T2D were extracted from genome-wide association studies. Summary-level results of CTS were available through FinnGen repository. Univariable Mendelian randomization (MR) with inverse-variance-weighted method indicated a positive correlation of BMI with CTS risk [odds ratio (OR) 1.66, 95% confidence interval (CI), 1.39–1.97]. Genetically proxied T2D also significantly increased the risk of CTS [OR 1.17, 95% CI (1.07–1.29)]. The causal effect of BMI and T2D on CTS remained consistent after adjusting for each other with multivariable MR. Our mediation analysis indicated that 34.4% of BMI’s effect of CTS was mediated by T2D. We also assessed the effects of several BMI and glycemic related traits on CTS. Waist circumference and arm fat-free mass were also causally associated with CTS. However, the associations disappeared after adjusting for the effect of BMI. Our findings indicate that obesity and T2D are independent risk factors of CTS.

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

INTRODUCTION

Carpal tunnel syndrome (CTS) is a prominent compressive neuropathy. There are a number of risk factors for creating CTS but the effect of these factors on the severity of CTS is unclear. In this study, we aimed to assess the correlation of serum lipid profile and obesity with the severity of CTS.

METHODS

this cross-sectional study was conducted on 118 patients with idiopathic CTS. Blood samples were obtained for determining the serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL-C), and high-density lipoprotein (HDL-C) after 12 hours of overnight fasting. The participants were then divided into two groups of normal and abnormal serum lipids. Body mass index ≥ 30 kg/m2 was considered as obesity. The severity of CTS was determined based on the electrophysiological results and Boston CTS Questionnaire (BCTSQ) that evaluates symptoms severity (SSS) and functional status (FSS) of patients.

RESULTS

out of 118 participants, 108 patients performed lipid profile test that 41.17%, 50.42%, 25.21%, and 20.16% of them had TC ≥ 200, TG ≥ 150, LDL-C ≥ 130, and HDL-C < 60 milligrams per deciliter (mg/dl), respectively. The mean scores of SSS in patients with dyslipidemia including the high level of TC, TG, LDL-C, and low level of LDL-C were 34.59±7.86, 34.05±8.73, 34.93±8.21, and 33.48±7.56, respectively. There was no significant association between lipid profile and the symptom severity scale of CTS (p-value > 0.05). The mean BMI of participants was 31.35±5.35 kg/m2, and 58.5% of them had a BMI ≥ 30 kg/m2. The mean score of SSS and FSS was 33.18±8.24 and 24.43±7.12 in obese patients (BMI ≥ 30 kg/m2), and was 34.06±7.85 and 23.06±7.67 in patients with BMI < 30 kg/m2. We found no significant association between obesity with the SSS and FSS (p-value = 0.53 and 0.32, respectively). In terms of the relationship between electrophysiological grading with obesity, 44 (63.8%) of patients with BMI ≥ 30 kg/m2 and 22 (45.8%) patients with BMI < 30 kg/m2 had severe to extreme severe CTS. There was no significant association between obesity and the severity of CTS (p-value = 0.054).

CONCLUSION

the results of this study did not demonstrate an association between serum lipid profile and obesity with the severity of carpal tunnel syndrome. The findings of this study may not be extrapolated to other populations. Further studies with more samples are needed to investigate this association.

Health-care providers' perspectives on factors influencing return-to-work after surgery for nontraumatic conditions of the upper extremity

STUDY DESIGN

This study is a descriptive survey.

INTRODUCTION

Health care providers (HCPs) are key stakeholders who facilitate workers' return to work (RTW) following upper extremity surgery. Hand therapists play a major role in this process, yet we do not know if and/or how their perspectives differ from other HCPs.

PURPOSE OF THE STUDY

This study examined HCPs' opinion on factors that influence RTW after surgery for nontraumatic upper extremity conditions and whether HCPs from different disciplines differed in their opinion.

METHODS

HCPs (occupational therapists, physiotherapists, hand therapists, exercise physiologists, psychologists, surgeons, and general practitioners) completed a survey rating 50 factors on a worker's ability to RTW. Each factor was scored using a 5-point Likert scale from "not" to "extremely" influential, which was later dichotomised. Agreement was indicated at 75%. The level of disagreement between disciplines was examined.

RESULTS

Respondents (n = 787) identified 20 factors being influential on RTW. They are (in order from highest to lowest) poor pain coping (the highest, >85% of respondents), postoperative psychological state, RTW self-efficacy, employer/supervisor's support, employer's unwillingness for job modification, recovery expectations, job satisfaction, suitable duties availability, whether the job can be modified, and mood disorder diagnosis. There was agreement that two factors do not influence RTW, gender, and preemployment medical assessment. There was disagreement (P < .05) between HCP disciplines on six factors (obesity, comorbidities, doctors' RTW recommendation, diagnosis, fitness, income). There were no consistent patterns with respect to which professions disagreed across all six factors. Hand therapists differed from the other disciplines for three of the factors including diagnosis, comorbidities, and doctor's recommendation for RTW.

DISCUSSION

The factors that stakeholders agreed as having the greatest influence were mainly related to the worker (pain and psychological factors) and the workplace and are amenable to RTW interventions.

CONCLUSION

Interventions facilitating RTW and future research should consider the factors identified by HCPs in this study.

Body mass index changes: an assessment of the effects of age and gender using the e-norms method

Background

To validate e-norms methodology in establishing a reference range for body mass index measures. A new method, the extrapolated norms (e-norms) method of determining normal ranges for biological variables is easy to use and recently was validated for several biological measurements. We aimed to determine whether this new method provides BMI results in agreement with established traditionally collected BMI values.

Methods

We applied the e-norms method to BMI data from 34,384 individuals and compared the ranges derived from this method with those from a large actuarially based study and explored differences in the normal range by gender, and age.

Results

The e-norms derived range of healthy BMI in adults is from 22.7 to 30.6, and showed that BMI is consistently higher in men than in women and increases with age, except in subjects aged 80–98 years in whom healthy BMI appears to be lower.

Conclusions

Our e-norms derived healthy BMI ranges agree with traditionally obtained actuarially based methods, supporting the validity and ease of use of our method.

Electrodiagnostic Testing Characteristics of Diabetic People with Carpal Tunnel Syndrome

Objective  The present study aimed to correlate electroneuromyography (ENMG) findings in diabetic and nondiabetic subjects with carpal tunnel syndrome (CTS).

Methods  In total, 154 patients were evaluated in a hand surgery outpatient clinic. All ENMG tests were bilaterally performed by a single neurologist. Qualitative variables were described for all patients with CTS according to their diabetic status, and the chi-squared test was used to reveal any association. A joint model was adjusted to determine the influence of diabetes on ENMG severity in CTS patients.

Results  The sample consisted of 117 women and 37 men, with an average age of 56.9 years old. Electroneuromyography demonstrated bilateral CTS in 82.5% of the patients. Diabetes was identified in 21.4% of the cases. Severe ENMG was prevalent.

Conclusion  There was no association between diabetes and ENMG severity in patients with CTS. Level of evidence IV, case series.

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.

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

BACKGROUND

Carpal tunnel syndrome (CTS) may be associated with structural lesions or anatomical variations at the wrist, especially in patients whose symptoms are more severe in, or limited to, the nondominant hand. The aims of this study were to identify the type and frequency of structural abnormalities and anatomical variations, and to demonstrate the contribution of ultrasound in this subgroup of CTS patients.

METHODS

A retrospective chart review was performed on all patients referred to the electromyography laboratory who fulfilled the diagnostic criteria for CTS and who underwent neuromuscular ultrasound.

RESULTS

Of 114 CTS patients with symptoms mainly in nondominant hand, 51 (44.7%) had structural abnormalities or anatomical variations detected by ultrasound. In multivariable analysis, symptoms mainly in the nondominant hand and a body mass index (BMI) <30 kg/m² were the only independent variables significantly associated with structural findings, odds ratios 2.3 (P < .001) and 1.9 (P = .006), respectively.

CONCLUSIONS

Neuromuscular ultrasound, in addition to electrodiagnostic studies, should be considered in all CTS patients with symptoms more severe in nondominant hand as a significant number have abnormal structural abnormalities or anatomical variations that may be causative or change the therapeutic approach.

Diagnosis and Treatment of Carpal Tunnel Syndrome in A Tertiary Care Center in Mexico City

BACKGROUND

Carpal tunnel syndrome is the most common peripheral neuropathy affecting patients at productive age and has an important economical impact on those who suffer it. This study assessed the diagnostic performance of carpal tunnel syndrome´s signs and described the epidemiology at a tertiary care center in Mexico City.

METHODS

All patients diagnosed with carpal tunnel syndrome during a five-year period were included. Demographic data, electromyography results, positive clinical signs and the severity score according to the Italian scale were recorded. Diagnostic accuracy of Tinel and Phalen´s signs were calculated via odds ratio.

RESULTS

Totally, 650 patients were diagnosed and treated during a five-year period, 84% were female and 16% male, and the mean age was 55.8 years. The associated comorbidities were trigger finger (36.1%), thyroid disease (25.6%) and diabetes (20%). Diagnosis yielded for Phalen and Tinel signs were variable in each of the study groups (males and females) and showed to be beneficial in diagnosis of the disease.

CONCLUSION

Carpal tunnel syndrome is a complex disease in which clinical signs remain the cornerstone of diagnosis. Extension studies are useful to assess the severity of the disease.

Relationship Between Obesity and Severity of Carpal Tunnel Syndrome in Tanzania

Background: Carpal tunnel syndrome (CTS) is the most common focal mononeuropathy in the general population, and obesity is one of its established independent risk factors The prevalence of obesity in CTS patients and its association with CTS severity are yet to be fully studied among Tanzanians. In this study, we determined the frequency of obesity in patients with CTS and its relationship with the electrophysiological severity of CTS in a Tanzanian private tertiary level hospital. Methods: This is a retrospective observational and analytical study of patients referred for electrodiagnostic (EDX) evaluation of suspected CTS at the clinical neurophysiology laboratory of the Aga Khan Hospital, Dar es Salaam, Tanzania. All EDX studies done for CTS indications between August 1, 2017, and December 31, 2019, were reviewed. The frequency of CTS patients with obesity (body mass index >30 kg/m²) and overweight (25.0-29.9 kg/m²) was determined. Next, we explored the relationship between obesity and the electrophysiologic severity of CTS. Results: One-hundred nine hands were studied. The prevalence of obesity was 50.5% and overweight was 31.2%. Females were significantly more obese than males (P = 0.001). Many of the EDX parameters that defined CTS, including prolonged median nerve sensory and distal motor latencies as well as sensory conduction velocity, were significantly more abnormal in the obese when compared to the nonobese patients. On univariate analysis, severe CTS (stage 5) was commoner among nonobese patients (P = 0.031), while moderate CTS (stage3) was more prevalent among obese patients (P < 0.001). Multivariate regression analysis, however, revealed no effect of obesity on CTS severity (P = 0.490). Conclusion: Obesity and overweight are prevalent among this cohort with CTS, but did not predict severe CTS. The use of other indices of adiposity may show a trend.

Carpal tunnel syndrome and exposure to work-related biomechanical stressors and chemicals: Findings from the Constances cohort

Objective

To investigate the effects of co-exposure to biomechanical wrist stressors and chemicals on the risk of CTS in a large cohort of French workers.

Methods

Prospective study using the data collected at baseline and at the first 12 month-follow-up for the 18,018 participants included in the population-based Constances cohort between 2012 and 2015. CTS at follow-up and exposure to biomechanical wrist stressors and chemicals at baseline were assessed using a self-administered questionnaire. Associations between CTS and co-exposure to biomechanical wrist stressors and chemicals were studied using multivariate logistic regression models, adjusted for personal/medical factors.

Results

184 men (2.1%, 95%CI 1.8–2.4) and 331 women (3.6%, 3.2–3.9) free from chronic hand symptoms at baseline declared suffering from unilateral/bilateral CTS at follow-up. A potentiating effect of co-exposure to biomechanical wrist stressors and chemicals on the risk of CTS was found for both genders, with higher OR in the co-exposure group (OR = 3.38 [2.29–5.01] in men and OR = 4.12 [2.73–6.21] in women) than in the biomechanical exposure group (OR = 2.14 [1.51–3.03] in men and OR = 2.19 [1.72–2.78] in women) compared to no exposure group.

Conclusions

The study showed an association between CTS and co-exposure to biomechanical wrist stressors and chemicals, after adjustment for the main personal and medical factors. This finding should be confirmed using more objective case definition of CTS and assessment of the chemical exposure before drawing conclusions on the possible synergistic effects of mechanical stressors and chemical on the median nerve.

Protective mechanism against age-associated changes in the peripheral nerves

AIMS

Senescence is the normal decline in physiological functions due to aging that results in cell dysfunction. However, age-associated changes in peripheral nerves have not been elucidated. We observed histological changes in the sciatic nerves of young and older mice to investigate how peripheral nerves changed with age, and we evaluated protective mechanisms of peripheral nerves against aging.

MAIN METHODS

Sciatic nerves were collected from female C57BL/6 mice at the ages of 8 weeks (young group) and 78 weeks (aged group) and examined histologically. Using hematoxylin and eosin staining, the number and density of sciatic nerve axons were evaluated. Through immunofluorescence staining, the expression of nerve-specific proteins, oxidative stress markers, and a neuronal aging marker (REST/NRSF) were investigated, and the intensity of fluorescence was quantified. The differences between the groups were assessed, and age-associated peripheral nerve changes were evaluated. Statistical analysis was performed using the Mann-Whitney U test.

KEY FINDINGS

Although the number and density of axons did not differ significantly between the groups, they were lower in the aged group than in the young group. In addition, the fluorescence intensity of each marker did not differ significantly between the groups, but the expression of REST/NRSF alone was significantly higher in the aged group than in the young group (p < 0.05).

SIGNIFICANCE

This study suggested that peripheral nerve functions are preserved by the expression of REST/NRSF, which increases with age. Because oxidative stress did not change, the protective effects of REST/NRSF are considered to be related to oxidative stress.

Risk of carpal tunnel syndrome after parathyroidectomy in patients with end-stage renal disease: A population-based cohort study in Taiwan

Carpal tunnel syndrome (CTS) is the most common mononeuropathy in clinical practice. Some patients with end-stage renal disease (ESRD) often associate with tertiary hyperparathyroidism, and ultimately need parathyroidectomy (PTX). However, no studies have definitively demonstrated an effect of PTX on ESRD patients' quality of life. We selected 1686 patients who underwent PTX and 1686 patients who did not receive PTX between 2000 and 2010. These patients were propensity-matched with others by age, sex, and comorbidities at a ratio of 1:1. We used single and multivariable cox proportional hazard models to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). In this study, 116 ESRD patients developed CTS, and the CTS incidences were 7.33 and 12.5 per 1000 person-years for the non-PTX and PTX group. The results reveal that the incidence curve for the PTX group was significantly higher than that for the non-PTX group (log-rank test, P = .004). After adjustments were made for sex, age, and baseline comorbidities, the PTX group had a 1.70-fold higher risk of CTS (hazard ratio (HR) = 1.70, 95% confidence intervals (CI) = 1.17-2.47) than the non-PTX group. The results also demonstrated that female patients (HR = 1.60, 95% CI = 1.06-2.42) and patients with one or more comorbidities (HR = 1.79, 95% CI = 1.23-2.60) might have an increased risk of CTS. The subhazard ratio for CTS risk was 1.62 (95% CI = 1.12-2.36) for the PTX group compared with the non-PTX group in the competing risk of death. In conclusion, we revealed that ESRD patients who had undergone PTX may have an increased risk of CTS.

Cross-sectional Area Just Proximal to the Carpal Tunnel According to the Ulnar Variances: Positive Ulnar Variance and Carpal Tunnel Syndrome

PURPOSE

We evaluated the relationship between the area around the distal radioulnar joint according to the ulnar variances and the cross-sectional area using magnetic resonance imaging (MRI) scans in this prospective study of patients with carpal tunnel syndrome (CTS).

METHODS

From among a total of 243 patients who had been diagnosed with CTS between March 2012 and February 2017 at our hospital, 41 patients with positive ulnar variance were enrolled in group 1. As control groups, 39 healthy volunteers who underwent MRI evaluations were included in group 2 (neutral ulnar variance) and group 3 (negative variance). Basic demographic data, including age, sex, and body mass index, were recorded for all 3 groups. An area encompassing the contents of carpal tunnel (nerves/tendons) was designated as area "A," and the area just beneath the subcutaneous fat was designated as area "B" at the levels of the lunate (L) and pisiform (P) on axial MRI. Ratios of these areas ("A/B at L" and "A/B at P") were evaluated in terms of their correlations with ulnar variance.

RESULTS

Mean age, sex, and body mass index were not statistically different among the groups, respectively. Within each group, there was no difference between "A/B at L" and "A/B at P," respectively. When comparing the 3 groups, "A/B at L" and "A/B at P" were all significantly decreased in group 1 than in other groups. Regardless of the group, ulnar length negatively correlated with both "A/B at L" and "A/B at P" ratios.

CONCLUSIONS

We found a positive relationship between decreased cross-sectional area around the distal radioulnar joint and positive ulnar variance on radiologic investigation. These findings show the importance of variance in the positive ulna variance to the development of CTS.

Constitutional risk factors for focal neuropathies in patients referred for electromyography

BACKGROUND AND PURPOSE

It is well established that patient-related constitutional features predispose to focal peripheral neuropathies. Some of these risk factors were investigated in common focal neuropathies encountered in patients referred for electromyography.

METHODS

Gender, age, height and body mass index (BMI) were analysed retrospectively as risk factors for 11 focal neuropathies. In all, 9686 patients (age range 18-96 years; 58% women) were included from three different centres, with identical methods and equipment.

RESULTS

High BMI was related to carpal tunnel syndrome (CTS), ulnar neuropathy at the elbow (UNE), combined CTS and UNE, meralgia paraesthetica and lumbar radiculopathy. In women, CTS and Morton's metatarsalgia were more common, whilst long thoracic neuropathies, suprascapular neuropathies and UNE were more common in men. Older age increased the risk for CTS, UNE, Morton's metatarsalgia and radiculopathies.

CONCLUSIONS

Age, gender and BMI are important risk factors for many common focal neuropathies.

Hand Pain and Sensory Deficits: Carpal Tunnel Syndrome

The Academy of Orthopaedic Physical Therapy and the Academy of Hand and Upper Extremity Physical Therapy have an ongoing effort to create evidence-based clinical practice guidelines (CPGs) for orthopaedic and sports physical therapy management and prevention of musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability and Health (ICF). This particular guideline focuses on hand pain and sensory deficits in carpal tunnel syndrome. J Orthop Sports Phys Ther 2019;49(5):CPG1-CPG85. doi:10.2519/jospt.2019.0301.

Increased Risk of Coronary Artery Disease in People with a Previous Diagnosis of Carpal Tunnel Syndrome: A Nationwide Retrospective Population-Based Case-Control Study

Background

Existing literature suggests that an association exists between coronary artery disease (CAD) and carpal tunnel syndrome (CTS), but few researchers have explored whether CTS is a risk for CAD.

Materials and Methods

This large case-control study explored the association between CTS and CAD, using health insurance claims data from Taiwan's National Health Insurance Research Database (NHIRD) between January 2000 and December 2013. International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnostic codes identified 70,622 patients with CAD (ICD-9-CM codes 410–414; cases); 70,622 patients without CAD were frequency-matched by age, sex, and index year of CAD and served as controls.

Results

The likelihood of a previous diagnosis of CTS (ICD-9-CM codes 354.0, 354.1) was significantly higher in the CAD group than in the comparison control group (crude OR: 1.75, 95% CI 1.63-1.89; p<0.0001; adjusted OR: 1.46, 95% CI 1.34-1.58; p<0.0001).

Conclusion

A significant positive correlation was observed between CAD and a previous diagnosis of CTS.

Preferences in Sleep Position Correlate With Nighttime Paresthesias in Healthy People Without Carpal Tunnel Syndrome

BACKGROUND

Carpal tunnel syndrome has been associated with sleep position preferences. The aim of this study is to assess self-reported nocturnal paresthesias and sleeping position in participants with and without carpal tunnel syndrome diagnosis to further clinical knowledge for preventive and therapeutic interventions.

METHODS

A cross-sectional survey study of 396 participants was performed in young adults, healthy volunteers, and a patient population. Participants were surveyed on risk factors for carpal tunnel syndrome, nocturnal paresthesias, and sleep preferences. Binary logistic regression analysis was performed comparing participants with rare and frequent nocturnal paresthesias. Subanalyses for participants without carpal tunnel syndrome under and over 21 years of age were performed on all factors significantly associated with subclinical compression neuropathy in the overall population.

RESULTS

Thirty-three percent of the study population experienced nocturnal paresthesias at least weekly. Increased body mass index ( P < .001) and sleeping with the wrist flexed ( P = .030) were associated with a higher frequency of nocturnal paresthesias. Side sleeping was associated with less frequent nocturnal symptoms ( P = .003). In participants without carpal tunnel syndrome, subgroup analysis illustrated a relationship between nocturnal paresthesias and wrist position. In participants with carpal tunnel syndrome, sleeping on the side had a significantly reduced frequency of nocturnal paresthesias.

CONCLUSION

This study illustrates nocturnal paresthesias in people without history of carpal tunnel syndrome including people younger than previously reported. In healthy patients with upper extremity subclinical compression neuropathy, sleep position modification may be a useful intervention to reduce the frequency of nocturnal symptoms prior to developing carpal tunnel syndrome.

Acupuncture and related interventions for the treatment of symptoms associated with carpal tunnel syndrome

BACKGROUND

Carpal tunnel syndrome (CTS) is a compressive neuropathic disorder at the level of the wrist. Acupuncture and other methods that stimulate acupuncture points, such as electroacupuncture, auricular acupuncture, laser acupuncture, moxibustion, and acupressure, are used in treating CTS. Acupuncture has been recommended as a potentially useful treatment for CTS, but its effectiveness remains uncertain. We used Cochrane methodology to assess the evidence from randomised and quasi-randomised trials of acupuncture for symptoms in people with CTS.

OBJECTIVES

To assess the benefits and harms of acupuncture and acupuncture-related interventions compared to sham or active treatments for the management of pain and other symptoms of CTS in adults.

SEARCH METHODS

On 13 November 2017, we searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, AMED, CINAHL Plus, DARE, HTA, and NHS EED. In addition, we searched six Korean medical databases, and three Chinese medical databases from inception to 30 April 2018. We also searched clinical trials registries for ongoing trials.

SELECTION CRITERIA

We included randomised and quasi-randomised trials examining the effects of acupuncture and related interventions on the symptoms of CTS in adults. Eligible studies specified diagnostic criteria for CTS. We included outcomes measured at least three weeks after randomisation. The included studies compared acupuncture and related interventions to placebo/sham treatments, or to active interventions, such as steroid nerve blocks, oral steroid, splints, non-steroidal anti-inflammatory drugs (NSAIDs), surgery and physical therapy.

DATA COLLECTION AND ANALYSIS

The review authors followed standard Cochrane methods.

MAIN RESULTS

We included 12 studies with 869 participants. Ten studies reported the primary outcome of overall clinical improvement at short-term follow-up (3 months or less) after randomisation. Most studies could not be combined in a meta-analysis due to heterogeneity, and all had an unclear or high overall risk of bias.Seven studies provided information on adverse events. Non-serious adverse events included skin bruising with electroacupuncture and local pain after needle insertion. No serious adverse events were reported.One study (N = 41) comparing acupuncture to sham/placebo reported change on the Boston Carpal Tunnel Questionnaire (BCTQ) Symptom Severity Scale (SSS) at three months after treatment (mean difference (MD) -0.23, 95% confidence interval (CI) -0.79 to 0.33) and the BCTQ Functional Status Scale (FSS) (MD -0.03, 95% CI -0.69 to 0.63), with no clear difference between interventions; the evidence was of low certainty. The only dropout was due to painful acupuncture. Another study of acupuncture versus placebo/sham acupuncture (N = 111) provided no usable data.Two studies assessed laser acupuncture versus sham laser acupuncture. One study (N = 60), which was at low risk of bias, provided low-certainty evidence of a better Global Symptom Scale (GSS) score with active treatment at four weeks after treatment (MD 7.46, 95% CI 4.71 to 10.22; range of possible GSS scores is 0 to 50) and a higher response rate (risk ratio (RR) 1.59, 95% CI 1.14 to 2.22). No serious adverse events were reported in either group. The other study (N = 25) did not assess overall symptom improvement.One trial (N = 77) of conventional acupuncture versus oral corticosteroids provided very low-certainty evidence of greater improvement in GSS score (scale 0 to 50) at 13 months after treatment with acupuncture (MD 8.25, 95% CI 4.12 to 12.38) and a higher responder rate (RR 1.73, 95% CI 1.22 to 2.45). Change in GSS at two weeks or four weeks after treatment showed no clear difference between groups. Adverse events occurred in 18% of the oral corticosteroid group and 5% of the acupuncture group (RR 0.29, 95% CI 0.06 to 1.32). One study comparing electroacupuncture and oral corticosteroids reported a clinically insignificant difference in change in BCTQ score at four weeks after treatment (MD -0.30, 95% CI -0.71 to 0.10; N = 52).Combined data from two studies comparing the responder rate with acupuncture versus vitamin B_12, produced a RR of 1.16 (95% CI 0.99 to 1.36; N = 100, very low-certainty evidence). No serious adverse events occurred in either group.One study of conventional acupuncture versus ibuprofen in which all participants wore night splints found very low-certainty evidence of a lower symptom score on the SSS of the BCTQ with acupuncture (MD -5.80, 95% CI -7.95 to -3.65; N = 50) at one month after treatment. Five people had adverse events with ibuprofen and none with acupuncture.One study of electroacupuncture versus night splints found no clear difference between the groups on the SSS of the BCTQ (MD 0.14, 95% CI -0.15 to 0.43; N = 60; very low-certainty evidence). Six people had adverse events with electroacupuncture and none with splints. One study of electroacupuncture plus night splints versus night splints alone presented no difference between the groups on the SSS of the BCTQ at 17 weeks (MD -0.16, 95% CI -0.36 to 0.04; N = 181, low-certainty evidence). No serious adverse events occurred in either group.One study comparing acupuncture plus NSAIDs and vitamins versus NSAIDs and vitamins alone showed no clear difference on the BCTQ SSS at four weeks (MD -0.20, 95% CI -0.86 to 0.46; very low-certainty evidence). There was no reporting on adverse events.

AUTHORS' CONCLUSIONS

Acupuncture and laser acupuncture may have little or no effect in the short term on symptoms of CTS in comparison with placebo or sham acupuncture. It is uncertain whether acupuncture and related interventions are more or less effective in relieving symptoms of CTS than corticosteroid nerve blocks, oral corticosteroids, vitamin B₁₂, ibuprofen, splints, or when added to NSAIDs plus vitamins, as the certainty of any conclusions from the evidence is low or very low and most evidence is short term. The included studies covered diverse interventions, had diverse designs, limited ethnic diversity, and clinical heterogeneity. High-quality randomised controlled trials (RCTs) are necessary to rigorously assess the effects of acupuncture and related interventions upon symptoms of CTS. Based on moderate to very-low certainty evidence, acupuncture was associated with no serious adverse events, or reported discomfort, pain, local paraesthesia and temporary skin bruises, but not all studies provided adverse event data.

Use of various obesity measurement and classification methods in occupational safety and health research: a systematic review of the literature

BACKGROUND

This study systematically examined obesity research in occupational safety and health regarding the use of various obesity measurement and classification methods.

METHODS

A systematic search of the PubMed database on English language publications from 2000 to 2015 using related keywords and search of citations resulted in selection of 126 studies. They were categorized into two groups based on their main research question: 1) general physical or mental work-related functioning; and 2) task or body part specific functioning.

RESULTS

Regardless of the study group, body mass index (BMI) was the most frequently used measure. Over 63% of the studies relied solely on BMI to define obesity. In only 22% of the studies, body fat was directly measured by methods such as dual energy x-ray absorptiometry. Abdominal obesity was defined using waist circumference in recent years, and waist-hip ratio in earlier years. Inconsistent cut-offs have also been used across studies investigating similar topics.

CONCLUSIONS

Few authors acknowledged the limitations of using indirect obesity measures. This is in part due to the limited understanding of some occupational safety and health researchers regarding the complex issues surrounding obesity classification and also the mixed recommendations over the past 2-3 decades and across populations. Efforts need to be made to promote appropriate obesity measurement and reporting in this field.

Correlation of clinical grading, physical tests and nerve conduction study in carpal tunnel syndrome

Background and aims Carpal tunnel syndrome (CTS) is a common debilitating condition. As the reliability of CTS-specific physical tests and its clinical grading remain a matter of debate, we determined the correlations between these assessments with nerve conduction study (NCS). Methods In this cross-sectional study, patients with uni or bilateral CTS, which was confirmed in electrodiagnosis, were enrolled. Clinical grading was based on the modified criteria of the Italian CTS Study Group. Numeric Pain Rating Scale (NPRS) and Boston Questionnaire (BQ) were used. Physical tests [Phalen's, reverse Phalen's, Tinel's and manual carpal compression test (mCCT)] were performed by a single blinded neurologist. A p-value<0.05 was considered statistically significant. Results A total of 100 patients (age=47.48±11.44 years; 85% female) with 181 involved hands were studied. The majority of hands (59.7%) were classified as grade 2 of clinical grading. On NCS, hands with mild (64%), moderate (27%) and severe (9%) CTS were identified. Sensory (velocity, latency and amplitude) and motor parameters (latency and amplitude) were significantly correlated with clinical grades (p-value<0.001). The correlation of NPRS (p-value=0.009) and BQ (p-value<0.001) scores with NCS was significant. None of the physical tests were significantly correlated with NCS in terms of result or duration (p-value>0.05). Conclusions We found that physical tests are not a reliable screening method for evaluation of CTS severity. However, the BQ and clinical grading can be more valuable due to their significant correlation with NCS. Implications Physicians might benefit from employing clinical grading and BQ in practice for better assessment of CTS severity.

Severity of Carpal Tunnel Syndrome and Diagnostic Accuracy of Hand and Body Anthropometric Measures

Objective

To study the diagnostic properties of hand/wrist and body measures according to validated clinical and electrophysiological carpal tunnel syndrome (CTS) severity scales.

Methods

We performed a prospective case-control study. For each case, two controls were enrolled. Two five-stage clinical and electrophysiological scales were used to evaluate CTS severity. Anthropometric measurements were collected and obesity indicators and hand/wrist ratios were calculated. Area under the receiver operating characteristic curves (AUC), sensitivity, specificity, and likelihood ratios were calculated separately by gender.

Results

We consecutively enrolled 370 cases and 747 controls. The wrist-palm ratio, waist-hip-height ratio and waist-stature ratio showed the highest proportion of cases with abnormal values in the severe stages of CTS for clinical and electrophysiological severity scales in both genders. Accuracy tended to increase with CTS severity for females and males. In severe stage, most of the indexes presented moderate accuracy in both genders. Among subjects with severe CTS, the wrist-palm ratio presented the highest AUC for hand measures in the clinical and electrophysiological severity scales both in females (AUC 0.83 and 0.76, respectively) and males (AUC 0.91 and 0.82, respectively). Among subjects with severe CTS, the waist-stature ratio showed the highest AUC for body measures in the clinical and electrophysiological severity scales both in females (AUC 0.78 and 0.77, respectively) and males (AUC 0.84 and 0.76, respectively). The results of waist-hip-height ratio AUC were similar.

Conclusions

Wrist-palm ratio, waist-hip-height ratio and waist-stature ratio could contribute to support the diagnostic hypothesis of severe CTS that however has to be confirmed by nerve conduction study.

Gender differences in carpal tunnel relative cross-sectional area: a possible causative factor in idiopathic carpal tunnel syndrome

Previous research has not established a consistent difference in hand size or carpal tunnel cross-sectional area between patients with and without carpal tunnel syndrome. We tested the hypothesis that there would be no difference in relative carpal tunnel sizes between men and women. We defined relative carpal tunnel size as the cross-sectional areas at the inlet (level of the pisiform) and outlet (level of the hook of the hamate) of the carpal tunnel divided by the length of the capitate (as a measure of hand size). We made the measurements on the magnetic resonance imaging scans of 50 men and 50 women taken for symptoms unrelated to carpal tunnel syndrome. The mean relative cross-sectional area was appreciably smaller in women than men (p < 0.05). This suggests that the carpal tunnel cross-sectional area relative to the size of the hand is constitutionally smaller in women than in men. This could in theory be a significant factor in patients developing carpal tunnel syndrome.

LEVEL OF EVIDENCE

V.

Carpal Tunnel Syndrome in Obstructive Sleep Apnea Patients

Introduction

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper extremity. It is usually associated with the compression of the median nerve in the median groove. Because the main symptoms of CTS pain and numbness worsen at night, sleep disorders in CTS patients and the impact of preferred sleeping position on CTS development have been formerly studied. However, to the best of our knowledge, this is the first study assessing the frequency of CTS in obstructive sleep apnea (OSA) patients. This study aimed to determine the frequency of CTS in OSA patients and evaluate the causative relation between the two diseases.

Methods

Records of individuals who were admitted to our sleep laboratory were retrospectively scanned. Eighty patients who were diagnosed with OSA and did not have comorbidities that might cause OSA (e.g., diabetes mellitus, hypothyroiditis, rheumatic diseases, and cervical radiculopathy) were included in the study along with 80 healthy controls who matched for age, sex, and BMI of OSA patients. To maintain observer blindness, patients were not questioned regarding their symptoms or the clinical data that would be used in the study. All participants underwent nerve conduction studies. Those who were diagnosed with CTS were questioned regarding CTS symptoms and the preferred sleeping position. Subsequently, patients were given the Boston CTS questionnaire.

Results

CTS frequency in OSA patients was found to be 27.5%. There was no significant relation between preferred sleeping position or being a manual worker and having CTS.

Conclusion

CTS frequency in OSA patients is significantly higher than that in healthy individuals. In contrast to previous studies that have been performed in the absence of polysomnographic and electrophysiological data, in our study biomechanical factors were not associated with CTS presence. Therefore, we conclude that intermittent hypoxemia is the main etiological factor for CTS in OSA patients. Inflammation may be a common factor for etiopathogenesis for both diseases, but this hypothesis needs further investigation.

Carpal Tunnel Syndrome in Hypothyroidism

INTRODUCTION

Carpal Tunnel Syndrome (CTS) is an entrapment neuropathy that occurs due to compression of median nerve in the carpal tunnel and hypothyroidism is one of the important causes of CTS.

AIM

To study clinical profile of carpal tunnel syndrome in patients with primary hypothyroidism.

MATERIALS AND METHODS

This was cross-sectional study done in Smt. Kashibai Navale Medical College, Pune, Maharashtra. Adult patients with diagnosis of primary hypothyroidism were included in this study. Patients with other possible causes of CTS were excluded. Detailed medical history was obtained and all patients underwent clinical examination and nerve conduction study by electrophysiological method.

RESULTS

Total 36 adult patients were included in this study, 86.1% females and 13.9% males. CTS were found in 6 (16.7%) patients. Increased Body Mass Index (BMI) and presence of clinical symptoms and/or signs of CTS correlated independently with presence of CTS in hypothyroidism. (p-value- 0.03 and < 0.0001 respectively). No correlation was found between gender, age of the patient, duration of disease, serum TSH level, aetiology of the disease, thyroid hormone replacement therapy and occurrence of CTS in hypothyroidism.

CONCLUSION

Increase in BMI is an important risk factor for CTS in hypothyroidism and clinical evidence of CTS is a very sensitive parameter for the same.

In the Clinic. Carpal Tunnel Syndrome

This issue provides a clinical overview of carpal tunnel syndrome, focusing on screening and prevention, diagnosis, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.

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

BACKGROUND

Occupational 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.

METHODS

We 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.

RESULTS

We 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.

CONCLUSIONS

Occupational 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.

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

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSION

In clinical practice, the cutoff values for many anthropometric measurements have limited value as tools for the diagnosis of CTS.

Carpal tunnel syndrome and prediabetes: is there a true association?

BACKGROUND

Carpal tunnel syndrome (CTS) is probably associated with diabetes mellitus, but its link to prediabetes (PD) is unknown.

OBJECTIVE

To determine prevalence of PD and others risk factors in CTS.

METHODS

A cross-sectional study including 115 idiopathic CTS patients and 115 age-, gender-and body mass index (BMI)-matched controls was performed. Clinical, laboratory and neurophysiological evaluations were conducted in all subjects to confirm CTS diagnosis. CTS severity was graded on a standardized neurophysiological scale. PD was defined using strict criteria.

RESULTS

The prevalence of PD was similar in CTS and control groups (27% vs. 21.7%, respectively P=0.44). Nocturnal symptoms (91.3%) and moderate CTS (58.3%) were most frequently observed in CTS patients. In logistic regression analysis, PD was significantly correlated with age (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.01-1.09; P=0.006) and BMI (OR 1.08. 95% CI 1.01-1.16; P=0.026), but not with CTS (OR 0.82, 95% CI 0.43-1.53; P=0.537). CTS patients with PD had a significantly higher mean age compared to those without PD (53.8±10.2 vs. 49.5±8.6 years, respectively P=0.027). The frequency of age >60 years was significantly higher in CTS with PD than in CTS without PD (29.0% vs. 8.3%, respectively P=0.04) as was BMI >30kg/m(2) (64.5% vs. 33.3%, respectively P=0.03). No significant differences were observed between the two CTS groups with respect to gender, BMI, symptoms, and neurophysiological severity of CTS.

CONCLUSIONS

Our findings indicated that CTS is not associated with PD, but that PD is closely linked to age and overweight.

Carpal Tunnel Syndrome in Patients with Tremor Dominant Parkinson's Disease

Background

Unilateral hand tremor is one of the cardinal symptoms of Parkinson’s disease. Additionally, mechanical traumatic hand movement is one of the risk factors for carpal tunnel syndrome. Our objective in this study was to examine whether repetitive mechanical movement may be related to the development of carpal tunnel syndrome in Parkinson’s disease with unilateral hand tremor using neurophysiological methods.

Methods

The study participants included 33 de novo Parkinson’s disease patients with unilateral hand tremor, and we compared the tremor hand and non-tremor hand within the same patients.

Results

Seven (21.2%) of the 33 patients had carpal tunnel syndrome. All of carpal tunnel syndrome patients showed neurophysiological abnormalities in both the hand without tremor and the hand with tremor. In addition, in patients without carpal tunnel syndrome, the sensory nerve action potential was lower in the hand without tremor than in the hand with tremor, although there were no significant differences.

Conclusions

We concluded that hand tremor in de novo Parkinson’s disease patients was not directly related to the development of carpal tunnel syndrome. In contrast, more frequent use of hand without tremor may induce mechanical loading and may be associated with CTS in the hand without tremor. Early diagnosis of Parkinson’s disease and proper education in hand use may be essential for preventing carpal tunnel syndrome in Parkinson’s disease tremor patients.

Presence or absence of palmaris longus and fifth superficial flexor digitorum; is there any effect on median nerve surface area in wrist sonography

Background:

Carpal tunnel syndrome (CTS) describes a set of symptoms caused by compression of the median nerve in the wrist, which is the most common site of nerve compression in the upper limb. This syndrome is a primary source of pain and reduced function in these patients, and the cause is compression of the median nerve where it passes beneath the flexor retinaculum in the wrist.

Objectives:

The aim of the present cross sectional study is to assess the absence of palmaris longus and fifth superficial flexor digitorum tendon as normal anatomic variations on the sonographic measurement of median nerve surface area in healthy individuals’ wrists.

Patients and Methods:

Ninety-three healthy volunteers underwent clinical evaluation for determining the presence of tendons in both wrists and sonographic measurement of median nerve surface area.

Results:

In 41 of 186 (22%) hands, the palmaris longus tendon was absent and absence of the fifth flexor digitorum tendon was noted in eight (4.30 %). The median surface area in the hands without palmaris longus was meaningfully lower than the hands with it (P = 0.025), while the difference in the median surface area was not statistically significant with regard to presence of the fifth flexor digitorum tendon (P = 0.324).

Conclusions:

Based upon the findings of the present study, it seems that the median surface area as a sonographic finding is probably related to presence or absence of the palmaris longus tendon, so that hands with the tendon present have larger surface areas. In addition, it seems that this sonographic finding does not depend on the function of the fifth superficial flexor digitorum tendon. Therefore, no correlation between CTS and the presence of palmaris longus tendon should be observed.

Carpal tunnel syndrome - Part I (anatomy, physiology, etiology and diagnosis)

Carpal tunnel syndrome (CTS) is defined by compression of the median nerve in the wrist. It is the commonest of the compressive syndromes and its most frequent cause is idiopathic. Even though spontaneous regression is possible, the general rule is that the symptoms will worsen. The diagnosis is primarily clinical, from the symptoms and provocative tests. Electroneuromyographic examination may be recommended before the operation or in cases of occupational illnesses.

The role of ultrasound in the diagnosis and management of carpal tunnel syndrome: a new paradigm

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy, affecting 9% of women, and it is responsible for significant morbidity and occupational absence. Clinical assessment is used for initial diagnosis and nerve conduction (NC) studies are currently the principal test used to confirm the diagnosis. Sensitivity of NC studies is >85% and specificity is >95%. There is now good evidence that US can be used as an alternative to NC studies to diagnose CTS. US can assess the anatomy of the median nerve and also identify pathology of the surrounding structures that may compress the nerve. Median nerve enlargement (cross-sectional area ≥10 mm(2) at the level of the pisiform bone or tunnel inlet) is the most commonly used parameter to diagnose CTS on US, and sensitivity has been reported to be as high as 97.9% using this parameter. US may also be used to guide therapeutic corticosteroid injection into the carpal tunnel--thus avoiding median nerve injury--and to objectively monitor the response to treatment. There is now sufficient evidence to propose a new paradigm for the diagnosis of CTS that incorporates US. US is proposed as the initial diagnostic test in CTS based on similar sensitivity and specificity to NC studies but higher patient acceptability, lower cost and additional capability to assess carpal tunnel anatomy and guide injection.