A Longitudinal Study of Industrial and Clerical Workers: Incidence of Carpal Tunnel Syndrome and Assessment of Risk Factors

Abstract

This study followed workers over an extended period of time to identify factors which may influence the onset of Carpal Tunnel Syndrome (CTS). The purpose was to evaluate incidence of CTS and to create a predictive model of factors that play a role in the development of CTS. This prospective study followed 432 industrial and clerical workers over 5.4 years. Incident cases were defined as workers who had no prior history of CTS at baseline testing and were diagnosed with CTS during the follow-up period or at the follow-up screening. On the basis of logistic regression, significant predictors for CTS include baseline median-ulnar peak latency difference, a history of wrist/hand/finger tendonitis, a history of numbness, tingling, burning, and/or pain in the hand, and work above the action level of the peak force and hand activity level threshold limit value. This longitudinal study supports findings from previous cross-sectional studies identifying both work related ergonomic stressors and physical factors as independent risk factors for CTS.

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

“…Nathan and his colleagues found 34 incident CTS cases among 256 industrial workers during an 11-year follow-up, resulting in an estimated incidence of 12.0 per 1000 person-years (45). In the prospective study of Gell et al (35) among 432 industrial and clerical workers with an average follow-up of 5.4 years, a similar incidence of 12.4 per 1000 person-years was observed. Given this low incidence, cohort studies with a low exposure prevalence will be strongly underpowered with respect to demonstrating significant associations, even with OR values of 2.0 or higher, unless very large populations are studied.…”

“…In eight studies, no significant differences were observed, the OR values ranging from 0.91 to 1.63 (33)(34)(35)(36)(37)(38)(39)(40). Jobs with the highest increased occurrence of CTS included work in the meatand fish-processing industry (OR 76.5), forestry work with chain saws (OR 21.3), and electronic assembly work (OR 11.4).…”

Systematic evaluation of observational methods assessing biomechanical exposures at work

“…The correspondence has been moderate, even though the strain index identified more hazardous jobs than the HAL method (74,75). An association with upper-limb disorders has been seen in several cross-sectional studies (75,78,83,84) as well as in prospective longitudinal studies (85)(86)(87)(88)(89)(90). The intra-and inter-observer repeatability has been moderate to good (82,91).…”

Risk Factors for Carpal Tunnel Syndrome and Median Neuropathy in a Working Population

“…Among earlier studies of the work-relatedness of CTS, many had small sample sizes, used varying definitions of CTS, and did not consistently account for known personal risk factors such as increasing age, high body mass index (BMI), and comorbid diseases such as diabetes mellitus.8, 9 Similarly, numerous recent studies characterizing the personal factors associated with CTS have not adequately measured or analyzed occupational factors.8, [10][11][12] Other recent studies have shown that both personal and occupational factors are independently associated with CTS. [13][14][15] Evaluating the independent contributions of occupational versus nonoccupational risk factors for CTS has implications for prevention, treatment, and for medical-legal issues.…”