The expression of estrogen receptors in the tenosynovium of postmenopausal women with idiopathic carpal tunnel syndrome

Comprehensive gene expression analysis using RNA sequencing between male and female patients with idiopathic carpal tunnel syndrome

Idiopathic carpal tunnel syndrome is the most common entrapment neuropathy in hand surgery, and it is characterized by Noninflammatory fibrosis of subsynovial connective tissues. The prevalence and incidence differ between male and female individuals, and the mechanism underlying this difference remains largely unclear. In the present study, we collected subsynovial connective tissues from six male and six female patients diagnosed with idiopathic carpal tunnel syndrome during surgery. We performed a comprehensive gene expression analysis using RNA sequencing to compare the gene expression profiles between male and female patients with idiopathic carpal tunnel syndrome. We identified 26 genes with significantly different expressions between male and female patients, in which POSTN, COL1A1, and COL3A1, which are involved in extracellular matrix organization, and IGF1, an important fibrotic factor, were significantly upregulated in male patients. Immunohistochemistry confirmed the expression of proteins encoded by these genes in tissues, and male patients tended to show increased POSTN expression. Our results indicate that fibrosis of subsynovial connective tissues is induced by different mechanisms in male and female patients, and genes involved in extracellular matrix organization, especially POSTN, might be important factors in male patients. This study provides insight into the pathogenesis of idiopathic carpal syndrome and might contribute to the development of new treatment strategies.

The association between menopausal status and clinical outcomes of female patients with carpal tunnel release: a retrospective observational study

BACKGROUND

The relationship between menopausal status and clinical outcomes of female patients with carpal tunnel release (CTR) has been not clearly investigated. This study aimed to evaluate the clinical outcomes of CTR among women with different menopausal statuses.

METHODS

Two hundred-eighteen consecutive female patients with carpal tunnel syndrome (CTS) who underwent surgery at our hospital between May 2016 and May 2020 were included in this study. Based on whether subjects had undergone menopause before surgery, they were divided into three groups: the premenopausal group, the early postmenopausal group (less than 10 years since menopause) and the late postmenopausal group (more than 10 years since menopause). The clinical outcome was assessed before surgery and at six-month postoperative visits using the Boston Carpal Tunnel Questionnaire (BCTQ).

RESULTS

There were 86 patients in the premenopausal group, 70 patients in the early postmenopausal group and 62 patients in the late postmenopausal group. All the groups showed significant improvements in their Symptom Severity Scale (SSS) and Functional Status Scale (FSS) compared with preoperative scores. Although, there was a significant difference between the groups based and post-surgical SSS and FSS (p < 0.05). Patients in the postmenopausal group had less improvement in SSS and FSS in comparison with those in the other groups (p < 0.05).

CONCLUSIONS

Our results showed that all the groups had significant improvement in their SSS and FSS. However, the clinical outcomes were poorer in late postmenopausal patients than in premenopausal or early postmenopausal patients. These findings can be used in pre-operative counseling and interpretation of outcomes in women with CTR.

Equol production capability and family history as risk factors for hand osteoarthritis in menopausal and postmenopausal women. Cross-sectional study

BACKGROUND

Hand disorders are common in menopausal women. Equol is a soy metabolite produced in humans and its production level differs among individuals. The purpose of this research is to investigate the correlative relationship between variables indicating equol production levels and the occurrence of hand disorders in menopausal and postmenopausal women.

METHODS

Female subjects were divided into two groups: women 45-70 years of age with hand osteoarthritis (patient group) and women in the same age range without hand osteoarthritis (control group). The equol production level of each subject was estimated by measuring her urine equol concentration. We also surveyed the subjects' family histories of osteoarthritis.

RESULTS

Equol levels in the patient group were significantly lower than those in the control group (p < 0.05). This difference was most apparent for women in their 50s. Individuals with family histories of Heberden's and Bouchard's nodes were found to be 48.1 times more likely to develop these conditions than individuals in the control group.

CONCLUSIONS

Women with early menopausal hand symptoms (i.e., stiff and arthritic hands) often develop hand osteoarthritis during their late menopausal and postmenopausal periods, which may cause their QoL to significantly deteriorate. Although a link between the probability of women developing hand osteoarthritis and their clinical backgrounds (i.e., family history) had been suspected, it had not been thoroughly investigated. Our survey of women with and without Heberden's nodes and Bouchard's nodes found a significant correlation between the likelihood of women developing osteoarthritis and a family history of this disease. We also found a significant correlation between the likelihood of women developing hand osteoarthritis and their equol production levels. These results indicate that women with family histories of finger osteoarthritis and low equol production have higher risks of developing finger osteoarthritis.

Carpal tunnel syndrome

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

High incidence of trigger finger after carpal tunnel release: a systematic review and meta-analysis

INTRODUCTION

Trigger finger (TF) often occurs after carpal tunnel release (CTR), but the mechanism and outcomes remain inconsistent. This study evaluated the incidence of TF after CTR and its related risk factors.

MATERIALS AND METHODS

​PubMed, Embase, and Scopus databases were searched up to 27 August 2022, with the following keywords: "carpal tunnel release" and "trigger finger". Studies with complete data on the incidence of TF after CTR and published full text. The primary outcome was the association between CTR and the subsequent occurrence of the TF and to calculate the pooled incidence of post-CTR TF. The secondary outcomes included the potential risk factors among patients with and without post-CTR TF as well as the prevalence of the post-CTR TF on the affected digits.

RESULTS

Ten studies with total 10,399 participants in 9 studies and 875 operated hands in one article were included for meta-analysis. CTR significantly increases the risk of following TF occurrence (odds ratio=2.67; 95% CI 2.344-3.043; P <0.001). The pooled incidence of TF development after CTR was 7.7%. Women were more likely to develop a TF after CTR surgery (odds ratio=2.02; 95% CI 1.054-3.873; P =0.034). Finally, the thumb was the most susceptible fingers, followed by middle and ring fingers.

CONCLUSIONS

High incidence of TF comes after CTR, and women were more susceptible than man. Clinicians were suggested to notice the potential risk of TF after CTR in clinical practice.

LEVEL OF EVIDENCE

Level III, meta-analysis.

Clinical Characteristics and Treatment of Adult Idiopathic Carpal Tunnel Syndrome Accompanied with Trigger Digit

Purpose

To investigate the clinical characteristics and treatment of adult idiopathic carpal tunnel syndrome (CTS) accompanied with trigger digit.

Materials and Methods

A retrospective analysis was performed on a total of 74 patients with adult idiopathic CTS accompanied with trigger digit admitted to and treated at the Hand Surgery Department of Ningbo No. 6 Hospital from January 1, 2017 to December 31, 2019. Data on patients' gender, age, occupation, course of the disease, menstruation, surgeries, examination-related information, complications, treatment methods, and prognoses during follow-up were recorded and subsequently used to analyze the pathogeneses, clinical characteristics, and treatment.

Results

A total of 74 patients (72 females and 2 males) were included. Among female patients, 51 were postmenopausal and 18 were non-postmenopausal. There were 101 fingers with trigger digit, including 14 patients with trigger digit in both hands, and 115 wrists affected by the CTS. The average course of CTS was 34.5 ± 49.3 months, and that of trigger digit was 10.5 ± 22.4 months. Seventy had both trigger digit and CTS in one hand, while among patients with both hands involved, only 4 had trigger digit or CTS in one hand. Eighty-nine fingers underwent A1 pulley release, and 104 hands underwent carpal tunnel surgery, with steroids being injected under the adventitia of the median nerve during the surgery. All patients who underwent surgeries had I/A-healed incisions, and 14 of them had obvious synovial hyperplasia observed in the carpal tunnel and flexor tendon sheath during surgeries. Follow-up visits, which lasted 3 to 35 months, had an average duration of 1.34 years and included 72 patients. In 63 patients (63/72), the syndrome of tenosynovitis and numbness disappeared and normal hand functions were restored; in 6 patients, the numbness in hands greatly improved and normal hand functions were almost completely restored, while no improvement in numbness of hands and limited hand functions were still observed in 3 patients.

Conclusion

CTS accompanied with trigger digit was more common in postmenopausal females, and the course of CTS was longer than that of trigger digit. CTS and trigger digit were more likely to simultaneously occur in the same hand, while some patients might not have obvious synovial hyperplasia in the carpal tunnel. Surgeries were effective in severe cases.

Association between hormone replacement therapy and carpal tunnel syndrome: a nationwide population-based study

OBJECTIVE

Carpal tunnel syndrome (CTS) is the most common compressive focal mononeuropathy, and the increased incidence in postmenopausal and pregnant women suggests its association with oestrogen. The objective of this study is to evaluate the relationship between hormone replacement therapy (HRT) and the occurrence of CTS.

DESIGN

Population-based case-control study.

SETTING

Nationwide health insurance programme operated by the government with a near 100% coverage rate.

PARTICIPANTS

We identified women ≥45 years old in the Health Insurance Research Database of Taiwan, which contains data on a representative sample of one million enrollees. After exclusion of those who were diagnosed with CTS before the prescription of HRT, a total of 118 309 participants were included and followed up for 15 years starting from 1 January 1996. Both HRT and occurrence of CTS were identified using the insurance claims.

MAIN OUTCOME MEASURES

We identified incident patients of CTS and evaluated the association between HRT and CTS by calculating the OR.

RESULTS

Of the 4535 participants who developed CTS during the study period, 2334 (51.5%) were HRT recipients. In participants without CTS, the proportion of HRT recipients was 28.1%, yielding an OR of 2.72 with a 95% CI of 2.56 to 2.88. After adjustment for age, diabetes, rheumatoid arthritis, hypothyroidism, gout and obesity, the OR of CTS associated with HRT was 2.04 (95% CI 1.91 to 2.17). While HRT, diabetes, rheumatoid arthritis and gout had similar effects on CTS across all age groups, hypothyroidism and obesity had different effects on different groups.

CONCLUSION

This study observed a positive association between HRT and CTS, independent of age, diabetes, rheumatoid arthritis, hypothyroidism, gout and obesity. While the ORs of CTS associated with HRT were similar across age groups, those associated with hypothyroidism and obesity were not, indicating effect modifications by age.

Expression of Estrogen Receptor Alpha and Evaluation of Histological Degeneration Scores in Fibroblasts of Hypertrophied Ligamentum Flavum: A Qualitative Study

The most common spinal disorder in elderly is lumbar spinal stenosis (LSS), resulting partly from ligamentum flavum (LF) hypertrophy. Its pathophysiology is not completely understood. The present study wants to elucidate the role of estrogen receptor α (ER α) in fibroblasts of hypertrophied LF. LF samples of 38 patients with LSS were obtained during spinal decompression. Twelve LF samples from patients with disk herniation served as controls. Hematoxylin & Eosin (H&E) and Elastica stains and immunohistochemistry for ER α were performed. The proportions of fibrosis, loss and/or degeneration of elastic fibers and proliferation of collagen fibers were assessed according to the scores of Sairyo and Okuda. Group differences in the ER α and Sairyo and Okuda scores between patients and controls, male and female sex and absence and presence of additional orthopedic diagnoses were assessed with the Mann–Whitney U test. There was a tendency towards higher expression of ER α in LF fibroblasts in the hypertrophy group (p = 0.065). The Sairyo and Okuda scores were more severe for the hypertrophy group but, in general, not statistically relevant. There was no statistically relevant correlation between the expression of ER α and sex (p = 0.326). ER α expression was higher in patients with osteochondrosis but not statistically significant (p = 0.113). In patients with scoliosis, ER α expression was significantly lower (p = 0.044). LF hypertrophy may be accompanied by a higher expression of ER α in fibroblasts. No difference in ER α expression was observed regarding sex. Further studies are needed to clarify the biological and clinical significance of these findings.

The role of estrogen and progesterone receptors in the rotator cuff disease: a retrospective cohort study

Background

Rotator cuff (RC) tears represent a common cause of shoulder pain and dysfunction in adults. The disease affects primarily women and occurs mainly in the postmenopausal period.

This study aimed to investigate immunohistochemically the presence of estrogen receptor-alpha (ER-⍺), estrogen receptor-beta (ER-β) and progesterone receptor (PR) in the supraspinatus tendon of patients with RC tendinopathy, searching for gender differences of expression. A secondary aim was to evaluate potential links between their expression and the typical histopathological findings of the ailment.

Methods

Biopsies of the supraspinatus tendon were collected intraoperatively from 15 postmenopausal women and 9 men undergoing RC surgery. Specimens were stained with Haematoxylin/Eosin, Masson-Goldner Trichrome, Alcian Blu and immunohistochemical stainings for ER-⍺, ER-β and PR were performed. Tendon alterations were evaluated with the Bonar histopathological scale. Statistical tests used in this study were the Spearman correlation coefficient and the Mann-Whitney U test.

Results

In the supraspinatus tendon, cells expressed ER-⍺ (p = 0.043), ER-β (p = 0.048) and PR (p = 0.004) with statistically significant differences related to age and sex of patients. Immunoreactivity was seen in the nuclei of tenocytes and vascular cells. Postmenopausal women’s samples showed a markedly higher expression of these receptors compared to their male counterpart. There was a positive correlation between the expression of ER-⍺ and ER-β (r = 0.59; p = 0.02) and between ER-β and PR (r = 0.72; p = 0.002) in women’s samples. Furthermore, in postmenopausal women the PR expression decreased with age (r = − 0.56; p = 0.027). Only in women, the ER-β expression positively correlated with the total Bonar histopathological score (p = 0.019) and the ER-β vascular expression positively correlated with ground substance alterations (p = 0.029).

Conclusions

These results reveal that ERs and PR are present in the supraspinatus tendon of patients with RC tears, suggesting a role of sex hormones in the pathogenesis of the disease.

Risk of de novo severe carpal tunnel syndrome after bilateral oophorectomy: a population-based cohort study

OBJECTIVE

The incidence of carpal tunnel syndrome (CTS) is higher in women, and peaks around the age of menopause. Therefore, we investigated whether bilateral oophorectomy is associated with an increased risk of severe CTS.

METHODS

We included all of the 1,653 premenopausal women who underwent bilateral oophorectomy for a nonmalignant indication between 1988 and 2007, and a random sample of 1,653 age-matched referent women who did not undergo bilateral oophorectomy in Olmsted County, MN. Diagnoses of CTS assigned to women over their entire lifetime were identified in these two cohorts. The risk of de novo severe CTS after bilateral oophorectomy (or index date) was evaluated using Cox proportional hazards models adjusted for potential confounders.

RESULTS

Bilateral oophorectomy was associated with an increased risk of severe CTS (adjusted hazard ratio 1.65, 95% confidence interval 1.20-2.25). The risk was suggestively greater in women with lower body mass index, nulliparity, and with a benign ovarian indication for oophorectomy (nonsignificant interactions). We did not observe a protective effect of estrogen therapy after the oophorectomy. The findings were similar in secondary analyses considering the incidence of CTS of any severity or idiopathic CTS.

CONCLUSIONS

The risk of severe CTS, common in perimenopausal women, is increased after bilateral oophorectomy. The association may be causal or due to confounding. Therefore, the precise biological mechanisms explaining the association and the absence of a mitigating effect of estrogen therapy should be further investigated.

Differences in characteristics of carpal tunnel syndrome between male and female patients

BACKGROUND

Sex difference is known to be a risk factor of carpal tunnel syndrome. However, sex differences with regard to the clinical presentation of carpal tunnel syndrome have not received much attention. Thus, this study aimed to detect any difference in the characteristics of carpal tunnel syndrome between male and female and thereby add new insights into disease prevention.

METHODS

A total of 647 patients (male 193 hands and female 454 hands) with carpal tunnel syndrome who underwent endoscopic or open carpal tunnel release were retrospectively reviewed. The average age at time of surgery was 66 years. Clinical and electrophysiological data of all patients were collected. Six medical conditions, including trigger finger, diabetes mellitus, hemodialysis, hyperlipidemia, hypertension, and obesity were also investigated.

RESULTS

A significant difference was found in the distribution of comorbidities between the male and female groups. Particularly, the prevalence of diabetes mellitus, hemodialysis, and hypertension were significantly higher in the male group than in the female group. Meanwhile, the presence of thenar muscle atrophy was significantly higher in the female group than in the male group.

CONCLUSIONS

Women are more likely to experience carpal tunnel syndrome even though they have no comorbidities. We suggest that carpal tunnel syndrome especially in male patients may be reduced by early intervention for diabetes mellitus. Prospective studies are needed to validate the causal relationship between diabetes mellitus and carpal tunnel syndrome.

Second to fourth digit ratio (2D:4D) in women with carpal tunnel syndrome

BACKGROUND

Carpal tunnel syndrome (CTS), a median nerve compressive neuropathy at the wrist, is the most common entrapment nerve disorder. Sex is an important risk factor of CTS as this condition is to five times more common in women than in men (sex-hormone dependent). There are no studies concerning 2D:4D (biomarker of prenatal sex steroids exposure) in patients with CTS.

AIM

Here we consider the relationship between 2D:4D and CTS in women.

STUDY DESIGN AND METHODS

The study involved 90 female participants (40 with a severe CTS (the mean age - 52.78 yrs., SD 11.44) and 50 control women (the mean age - 47.2 yrs., SD 8.23)). Anthropometric measurements were performed and the following indices were calculated: BMI, WHR and right and left 2D:4D.

RESULTS

A stepwise logistic regression model showed that higher WHR and lower right 2D:4D increase the risk of CTS in women (AUC = 0.8865).

CONCLUSIONS

These associations may suggest a role for prenatal and post-natal sex-hormones in CTS development, i.e. in the context of oestrogen receptor activation (number and/or sensitivity) and the pattern of fat distribution. Further studies examining the role of hormonal influence in this disorder may help to plan prophylaxis of CTS (e.g. early HRT).

Observed Differences between Males and Females in Surgically Treated Carpal Tunnel Syndrome Among Non-manual Workers: A Sensitivity Analysis of Findings from a Large Population Study

Objectives

We aimed at assessing whether differences among males and females in carpal tunnel syndrome (CTS) epidemiology might be attributable to segregation with respect to occupational biomechanical exposures or differential access to care by sex.

Methods

We analysed surgically treated cases of CTS occurring among non-manual workers in Tuscany between 1997 and 2000. We conducted a Monte Carlo simulation to estimate the difference in occupational biomechanical exposures between males and females necessary to explain the observed incidence rate ratios. We also accounted for the sex-specific probability of receiving surgery after the diagnosis of CTS, as women were reported to be more likely to undergo surgery in a subset of our study population. We quantified the hypothetical biomechanical overload through the hand activity level (HAL) metric proposed by the American Conference of Governmental Industrial Hygienists. To quantify the effect of HAL on CTS risk, we assumed a prior distribution based on findings from two large cohort studies of industrial workers.

Results

After adjustment for the probability of receiving surgery, women showed a 4-fold incidence of CTS as compared with men. To explain this association among non-manual workers, women should have an average value of HAL at least 5 points higher.

Conclusions

Our analysis does not support the hypothesis that the difference in CTS incidence between males and females is entirely attributable to occupational risk factors or to differential access to surgery. The causal pathway between sex and CTS might include more determinants such as hormonal factors, anthropometric characteristics, and non-occupational exposure to biomechanical overload (e.g. household tasks).

Hand tendinopathy risk factors in Taiwan: A population-based cohort study

De Quervain's disease, carpal tunnel syndrome (CTS), and trigger finger (digit) are three common pathological conditions of the hand. They are considered overuse syndromes and occur predominantly in females. The prevalence rate and cause-specific risks of these three tendinopathies have not yet been clarified. Data from 41,871 cases listed in the Taiwan National Health Insurance Research Database (NHIRD) from 2010 to 2014 were analyzed. The prevalence rate of these 3 conditions by age, sex, and the risk factors of female-dominant diseases (e.g., osteoporosis, rheumatoid arthritis [RA], and tendinopathy), diabetes mellitus, and hormone antagonist treatment was evaluated. We found that 1.59% of the population developed CTS, 0.49% developed de Quervain's, and 1.07% developed trigger finger. Cases were more likely to develop the three hand tendinopathies if they were female, between 50 and 59 years old, and, according to a multivariate analysis, comorbid with RA, diabetes, using hormone antagonists. Our findings should provide an understanding of the risk factors associated with hand tendinopathy.

Menopausal hormone therapy and the incidence of carpal tunnel syndrome in postmenopausal women: Findings from the Women's Health Initiative

Importance

Carpal tunnel syndrome (CTS) is a common and debilitating condition that commonly affects postmenopausal women.

Objective

To determine the effect of menopausal hormone therapy (HT) in healthy postmenopausal women on CTS risk.

Design

We conducted a secondary analysis of the Women’s Health Initiative’s (WHI) HT trials linked to Medicare claims data. Separate intention-to-treat analyses were performed for the two trials; the conjugated equine estrogens alone (CEE alone) and the trial of CEE plus medroxyprogesterone acetate (MPA) trial. (ClinicalTrials.gov, NCT number): NCT00000611.

Setting

Two randomized, double-blind, placebo-controlled trials conducted at 40 US clinical centers.

Participants

The sample size included in the analysis was 16,053 community-dwelling women aged ≥65 years at study entry or those who later aged into Medicare eligibility, and who were enrolled in Medicare (including Part A and/or Part B coverage).

Intervention

Women with hysterectomy were randomized to 0.625 mg/d of conjugated equine estrogens (CEE) or placebo (n = 8376). Women without hysterectomy were randomized to estrogen plus progestin (E+P), given as CEE plus 2.5 mg/d of medroxyprogesterone acetate (n = 14203).

Main outcome(s)

The primary outcome was incident CTS and the secondary outcome was therapeutic CTS procedure occurring during the intervention phases of the trials.

Results

A total of 16,053 women were randomized in both trials. During mean follow up of 4.5 ± 2.8 years in the CEE trial (n = 6,833), there were 203 incident CTS cases in the intervention and 262 incident CTS cases in the placebo group (HR, 0.78; 95% CI, 0.65–0.94; P = 0.009). The CEE+MPA trial (n = 9,220) followed participants for a mean of 3.7 ± 2.3 years. There were 173 incident CTS cases in the intervention compared to 203 cases in the placebo group (HR, 0.80, 95% CI, 0.65–0.97; P = 0.027).

Conclusions

These findings suggest a protective effect of menopausal HT on the incidence of CTS among postmenopausal women. A potential therapeutic role for other forms of estrogen therapy in the management of CTS warrants future research.

Estrogen and mechanical loading-related regulation of estrogen receptor-β and apoptosis in tendinopathy

Female-dominant tendinopathies are musculoskeletal disorders caused by repetitive hand posture and motion; they are considered overuse syndromes. Both external mechanical stress and changes in hormone levels might affect disease progression. We have previously reported that estrogen receptor-β (ER)-β expression was associated with the pathogenesis of de Quervain's disease. To study the underlying mechanisms, a cyclic stretching culture system was applied to tendon tissue from ovariectomized (OVX) rats. Furthermore, a collagenase I-induced rat tendinopathy model was established to examine the association of ER-β with disease progression. Our results showed that ER-β expression and the number of apoptotic cells were higher and associated with disease severity in rats with tendinopathy. Mechanical stress altered the morphology of primary tenocytes and collagen fiber alignment in tendons, and up-regulated the expression of matrix metalloproteinase-9, ER-β, and interleukin-1β, as well as induced apoptosis in tenocytes and tendon tissue from OVX rats. This is the first report on the effects of ER-β and mechanical stress in tendinopathy. We hope these findings contribute to new pharmacological therapies targeting ER-β signaling pathways to treat tendon-related diseases.

Effect of estradiol on fibroblasts from postmenopausal idiopathic carpal tunnel syndrome patients

Fibrosis of the subsynovial connective tissue (SSCT) is a characteristic finding in patients with idiopathic carpal tunnel syndrome (CTS). Idiopathic CTS frequently occurs in postmenopausal women; therefore, female steroid hormones, especially estrogens, may be involved in its development. In this study, we evaluated the effect of the estradiol on the expression of genes and proteins related to fibrosis of SSCT fibroblasts from patients with idiopathic CTS. This study included 10 postmenopausal women (mean age 76 years). Fibroblasts derived from SSCT were treated with estradiol (10^-4 -10^-12  M), and the expression levels of TGF-β-responsive genes were evaluated. The relationships between the expression of untreated estrogen receptor α (ERα) and ERβ and changes in gene expression due to estradiol treatment were examined by quantitative real-time polymerase chain reaction. The effects of 10^-4  M estradiol on collagen type I (Col1) and collagen type III (Col3) protein expression levels were also evaluated by fluorescent staining. The relationships between ERα/β and Col1/3 expression were evaluated by immunohistochemical staining. The reduction in Col1A1 mRNA expression due to estradiol treatment was positively correlated with ERα expression (r = 0.903, p < 0.01). At the protein level, expression of Col1 and Col3 were down-regulated. These results indicated that ERα-mediated signaling may be involved in the regulation of Col1A1, and its regulatory effect may be dependent on the ERα expression level. The accurate evaluation of ERα expression level in the SSCT of individual patients with idiopathic CTS might guide the effective use of new estrogen replacement therapy.

Correlation between Female Sex Hormones and Electrodiagnostic Parameters and Clinical Function in Post-menopausal Women with Idiopathic Carpal Tunnel Syndrome

Objectives

To investigate the role of sex-hormonal changes in idiopathic carpal tunnel syndrome (CTS) among post-menopausal women through measuring estrogen receptor (ER) expression in their transverse carpal ligament (TCL) and serum estrogen level, as well as determine the correlation between these factors and electrodiagnostic parameters and Boston score.

Methods

Biopsy samples of TCL were collected from 12 postmenopausal women who had undergone surgery for severe idiopathic CTS; control specimens were collected from 10 postmenopausal women without CTS who had undergone surgery for the other hand pathologies. To determine the distributions of ER in TCL, histological and immunohistochemical examinations were performed. Serum estrogen level was also measured. Electrodiagnosis and Boston questionnaire were used for CTS severity and determination of the patients' function.

Results

ER expression in TCL and serum estrogen level were not significantly different in the case group compared to the control group (P = 0.79 and P = 0.88, respectively). Also, there was no correlation between ER expression or serum estrogen level and electrodiagnostic parameters or Boston score.

Conclusions

Sex hormones cannot still be considered as the etiology of idiopathic CTS in postmenopausal women. The role of other factors such as wrist ratio and narrower outlet in females compared to the males should be considered along with hormonal changes.

The Estrogen Receptor-β Expression in De Quervain's Disease

Stenosing tenosynovitis of the first dorsal compartment of the wrist (a.k.a. de Quervain’s disease) is common but how estrogen is involved is still unknown. We previously reported that inflammation was involved in the pathogenesis of this ailment. In the present study, we extended our investigation of estrogen receptor (ER)-β expression to determine whether estrogen is involved in the pathogenesis of de Quervain’s. Intraoperative retinaculum samples were collected from 16 patients with the ailment. Specimens were histologically graded by collagen structure and immunohistochemically evaluated by quantifying the expression of ER-β, interleukin (IL)-1β and IL-6 (inflammatory cytokines), cyclooxygenase (COX)-2 (an inflammatory enzyme), and vascular endothelial growth factor (VEGF), and Von Willebrand’s factor (vWF). De Quervain’s occurs primarily in women. The female:male ratio in our study was 7:1. We found that ER-β expression in the retinaculum was positively correlated with disease grade and patient age. Additionally, disease severity was associated with inflammatory factors—IL-1β and IL-6, COX-2, and VEGF and vWF in tenosynovial tissue. The greater the levels of ER-β expression, tissue inflammation, and angiogenesis are, the more severe de Quervain’s disease is. ER-β might be a useful target for novel de Quervain’s disease therapy.

Evaluation of female hormone-related symptoms in women undergoing carpal tunnel release

As carpal tunnel syndrome is more common in women, particularly around the menopause, female-related risk factors are suspected to play a role in its pathogenesis. We have assessed whether female hormone-related symptoms are associated with upper extremity disabilities in women undergoing carpal tunnel release. A total of 92 women with a mean age of 53 years scheduled for surgery for carpal tunnel syndrome were assessed preoperatively for female hormone-related symptoms using the menopausal rating scale and other female-related factors such as menopausal status, pregnancy number and serum female hormone levels. Upper extremity disability was evaluated using the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. DASH scores had a moderate correlation with total menopausal rating scale scores, but not with other female-related factors assessed. This study suggests that female hormone-related symptoms are associated with subjective upper extremity disabilities in women with carpal tunnel syndrome. This information may be helpful in addressing patients' complex symptoms or interpretation of outcomes in women with carpal tunnel syndrome.

Epidemiology of musculoskeletal upper extremity ambulatory surgery in the United States

Background

Musculoskeletal disorders of the upper extremity are common reasons for patients to seek care and undergo ambulatory surgery. The objective of our study was to assess the overall and age-adjusted utilization rates of rotator cuff repair, shoulder arthroscopy performed for indications other than rotator cuff repair, carpal tunnel release, and wrist arthroscopy performed for indications other than carpal tunnel release in the United States. We also compared demographics, indications, and operating room time for these procedures.

Methods

We used the 2006 National Survey of Ambulatory Surgery to estimate the number of procedures of interest performed in the United States in 2006. We combined these data with population size estimates from the 2006 U.S. Census Bureau to calculate rates per 10,000 persons.

Results

An estimated 272,148 (95% confidence intervals (CI) = 218,994, 325,302) rotator cuff repairs, 257,541 (95% CI = 185,268, 329,814) shoulder arthroscopies excluding those for cuff repairs, 576,924 (95% CI = 459,239, 694,609) carpal tunnel releases, and 25,250 (95% CI = 17,304, 33,196) wrist arthroscopies excluding those for carpal tunnel release were performed. Overall, carpal tunnel release had the highest utilization rate (37.3 per 10,000 persons in persons of age 45–64 years; 38.7 per 10,000 persons in 65–74 year olds, and; 44.2 per 10,000 persons in the age-group 75 years and older). Among those undergoing rotator cuff repairs, those in the age-group 65–74 had the highest utilization (28.3 per 10,000 persons). The most common indications for non-cuff repair related shoulder arthroscopy were impingement syndrome, periarthritis, bursitis, and instability/SLAP tears. Non-carpal tunnel release related wrist arthroscopy was most commonly performed for ligament sprains and diagnostic arthroscopies for pain and articular cartilage disorders.

Conclusions

Our data shows substantial age and demographic differences in the utilization of these commonly performed upper extremity ambulatory procedures. While over one million upper extremity procedures of interest were performed, evidence-based clinical indications for these procedures remain poorly defined.

Incidence of carpal tunnel release: trends and implications within the United States ambulatory care setting

PURPOSE

To investigate the changes, trends, and implications of carpal tunnel release (CTR) surgery within an ambulatory setting over the past decade in the United States.

METHODS

We undertook an analysis of ambulatory surgery center CTR cases using data from the National Survey of Ambulatory Surgery. The Centers for Disease Control and Prevention carried out this survey in 1996, and again in 2006. We searched the cases with the procedure codes indicative of CTR.

RESULTS

The number of CTR procedures increased by 38% (from 360,000 to 577,000) between 1996 and 2006. In 1996, 16% of all ambulatory CTRs were performed in freestanding ambulatory surgery centers (hospital-based centers were 84%), and the proportion increased to 49% in 2006. By 2006, greater than 99% of CTRs were performed in an ambulatory setting. There was a significant increase in women aged 50 to 59 years of age undergoing CTR.

CONCLUSIONS

The minimal invasiveness of CTR combined with the advent of ambulatory care facilities has made CTR a predominantly outpatient procedure. In contrast to other reports, our study demonstrated a higher incidence of CTR within the United States in 2006 compared with 1996. Elderly women, in particular, with CTS were 3 times more likely to be treated surgically than other age groups. Further study is needed to better define factors influencing CTR indications.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.