Influence of body mass index and work activity on the prevalence of median mononeuropathy at the wrist.

Abstract

OBJECTIVE: To determine which proposed risk factor, work activity (industrial v clerical), body mass index (BMI), or other demographic factors had the most influence on the prevalence of median mononeuropathy at the wrist, and if there was an interaction between the risk factors. METHODS: This was a cross sectional study of active workers at five different worksites; four were industrial sites and one was clerical. 527 workers were recruited--164 clerical and 363 industrial. The presence of a median mononeuropathy in either hand was measured by electrodiagnostic techniques comparing median and ulnar sensory latencies. RESULTS: 30% of workers had an abnormality of the median sensory nerve at the wrist (34% of the industrial v 21% of the clerical workers). The adjusted risk for industrial workers was twice that of clerical workers. Obese workers (BMI > 29) were four times more likely to present with a median mononeuropathy than workers who were normal or slender (BMI < 25). There was no significant interaction between BMI and worksite in relation to median mononeuropathy. Increasing age was also related to an increased risk of median mononeuropathy. CONCLUSIONS: Obesity, industrial work, and age are independent risk factors that influence the prevalence of median mononeuropathies among active workers.

Prolonged median sensory latency as a predictor of future carpal tunnel syndrome

“…We found the same relationship in our earlier studies, 11,16 and the National Institute of Occupational Safety and Health reached the same conclusion in its review of the literature. 4 Workers with a baseline prolongation of the median sensory response had a higher BMI, which is consistent with the reported literature, 15 but this factor did not significantly influence the development of future CTS symptoms.…”

Cross-sectional study of the relationship between repetitive work and the prevalence of upper limb musculoskeletal disorders

“…Finally, Werner et al [1997] compared a subset of the industrial workers who participated in this study to clerical workers. The same screening protocol and job analysis method were used to study the clerical workers.…”

Sensitive median-ulnar motor comparative techniques in carpal tunnel syndrome

“…He became symptomatic two months later. In a recent cross-sectional study of active workers, the occurrence of an asymptomatic median neuropathy at the wrist was often noted, 27 but it is unclear whether this situation represents a presymptomatic carpal tunnel syndrome or a normal variant. The 34 remaining controls were included for analysis, although palmwrist studies were performed in only 33 controls.…”