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

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

Ultrasound for carpal tunnel syndrome screening in manual laborers.

INTRODUCTION: Manual laborers are at increased risk for carpal tunnel syndrome (CTS), and a combination of history, physical examination, and nerve conduction studies is often used to screen for CTS in this population. Neuromuscular ultrasound may be a better screening tool, because it is painless. In this study we compare the accuracy of nerve conduction studies and ultrasound for CTS screening. METHODS: Five hundred thirteen manual laborers were screened prospectively for CTS using nerve conduction studies and neuromuscular ultrasound, and the accuracy of the 2 techniques was compared using the Katz hand diagram as the diagnostic standard. RESULTS: The ROC curves for the 2 techniques were not significantly different (P = 0.542), indicating that the approaches had similar diagnostic accuracy. CONCLUSIONS: Neuromuscular ultrasound is a painless technique that has diagnostic accuracy similar to nerve conduction studies and can be used to screen large populations at risk for CTS.

Carpal tunnel syndrome in Indian patients: use of modified questionnaires for assessment.

This study was conducted to assess the use of a modified carpal tunnel syndrome questionnaire (the Boston Carpal Tunnel Questionnaire, BCTQ) in an Indian patient population. Seventy-six Indian patients with carpal tunnel syndrome (CTS) were recruited to this prospective study. On a scale of one to five, the average score for the severity of symptoms was 2.09 (0.89). The average score for functional disability was 1.94 (0.74), which was lower than the average function score reported for Western CTS patients (Levine et al., 1993). The symptom severity and function disability scores were higher in patients with positive Tinel's sign and Phalen's test. The function disability score was moderately correlated with other clinical tests for CTS. The average modified BCTQ scores for Indian CTS patients was established through this study. This modified questionnaire might assist physicians in developing countries to assess disability from CTS, although socioeconomic and cultural differences will have to be taken into account when comparing assessments across different populations.

Clinical profile, electrodiagnosis and outcome in patients with carpal tunnel syndrome: a Singapore perspective.

INTRODUCTION: Carpal tunnel syndrome (CTS ) is the most common entrapment neuropathy seen in our neurodiagnostic laboratory referrals. We describe the clinical profile, and outcome in patients with electrophysiological diagnosis of CTS seen in our centre over a six month period. METHODS: A retrospective study was carried out and included 134 consecutive patients with CTS referred to the Neurodiagnostic Laboratory, National Neuroscience Institute, from October 2003 to March 2004, for the confirmatory testing. Severity grade was assigned following American Association of Electrodiagnostic Medicine criteria of CTS. RESULTS: The majority of patients were female (81.3 percent) with mean age of presentation being 53.6 years. Chinese women constitute the majority racial group. Paraesthesia (70.1 percent) and numbness (19.4 percent) were the presenting sensory symptoms. In the nerve conduction study, 108 patients had bilateral CTS with 35 having unilateral symptoms. Dominant hand involvement was present in 92.3 percent. Overall, 40.3 percent had mild, 46.3 percent had moderate and 13.4 percent had severe CTS, with median duration of symptoms of two, four and 12 months, respectively. Follow-up data were available for 115 patients. 27 patients with surgical treatment showed resolution or improvement in 53.3 percent with moderate CTS, and 83.3 percent with severe CTS, at three-month follow-up. 14 patients turned up for six-month follow-up and 92.9 percent showed improvement in symptoms. 88 patients were managed conservatively; symptoms were unchanged or worsened in 80.6 percent with mild CTS, 65.9 percent with moderate CTS, and 62.5 percent with severe CTS at three-month follow-up. Of the 54 patients who turned up for six-month follow-up, the clinical symptom remain unchanged or worsened in 68.5 percent. CONCLUSION: The severity of CTS is associated with longer duration of symptoms. Sensory symptoms and dominant hand involvement is more common. There is a high default rate in the clinical follow-up. Early surgical intervention results in either resolution or improvement in symptoms, whereas conservative management does not affect the natural history with symptoms that persisted or worsened with time.

Intergroup comparisons of carpal tunnel dimensions.

Although it is a common disease entity worldwide, idiopathic carpal tunnel syndrome is rarely seen in black South Africans. This study compares anatomic dimensions of the carpal canal in black and white population groups, using computed tomography. No significant anatomic differences were found between the groups tested; thus, other explanations need to be sought to explain the difference in occurrence of carpal tunnel syndrome in these groups. A parameter, the carpal canal index, was defined and may prove useful in future investigations of this region.

Prevalence and work-relatedness of self-reported carpal tunnel syndrome among U.S. workers: analysis of the Occupational Health Supplement data of 1988 National Health Interview Survey.

To estimate the prevalence and work-relatedness of self-reported carpal tunnel syndrome (CTS) among U.S. workers, data from the Occupational Health Supplement of 1988 National Health Interview Survey (NHIS) were analyzed. Among 127 million "recent" workers" who worked during the 12 months prior to the survey, 1.47% (95% CI: 1.30; 1.65), or 1.87 million self-reported CTS, and 0.53% (95% CI: 0.42; 0.65), or 675,000, stated that their prolonged hand discomfort was called CTS by a medical person. Occupations with the highest prevalence of self-reported CTS were mail service, health care, construction, and assembly and fabrication. Industries with the highest prevalence were food products, repair services, transportation, and construction. The risk factor most strongly associated with medically called CTS was exposure to repetitive bending/twisting of the hands/wrists at work (OR = 5.2), followed by race (OR = 4.2; whites higher than nonwhites), gender (OR = 2.2; females higher than males), use of vibrating hand tools (OR = 1.8), and age (OR = 1.03; risk increasing per year). This result is consistent with previous reports in that repeated bending/twisting of the hands and wrists during manual work is etiologically related to occupational carpal tunnel syndrome.

Amyloid polyneuropathy in two German-American families: a new transthyretin variant (Val 107).

We report studies on two German-American persons with systemic amyloidosis. Affected subjects presented with carpal tunnel syndrome in the sixth decade of life followed by peripheral neuropathy. DNA analysis of the transthyretin gene showed a new point mutation which is responsible for substitution of valine for isoleucine at position 107 of the transthyretin molecule.

Autosomal dominant carpal tunnel syndrome in a Karaite family.

A clinical examination and a history of 64 members belonging to four generations of a Karaite kindred revealed 11 patients with carpal tunnel syndrome (CTS). Bilateral involvement and early age of onset are salient features. The mutation may be traced in four generations. Hereditary primary CTS may be more prevalent than hitherto suspected.