To Örebro University

OBJECTIVE: To investigate the increased risk for carpal tunnel syndrome (CTS) in men and women with hand-arm vibration (HAV) exposure.

DESIGN: Case-control study of CTS where 4396 cases was obtained from National Outpatient Register between 2005 through 2016. Cases were matched to controls and exposure was estimated using a job exposure matrix.

RESULTS: Exposure to HAV increased the risk of CTS with an OR of 1.61 (95% CI 1.46-1.77). The risk was highest in men <30 years of age and among women <30 years no increased risk was observed. The risk increased with a mean year exposure above 2.5 m/s2 to OR 1.84 (95% CI 1.38-2.46).

CONCLUSIONS: HAV exposure increase the risk of CTS in both genders, with highest risk increase in younger men. This emphasize identification of HAV exposure in patients with CTS.

OBJECTIVE: This study was to investigate the acute effects of hand-arm vibrations on the nerve functions of the hands, and the impact of the grip force applied to the vibrating tool during exposure.

METHODS: Grip strength and perception of vibration, touch, and temperature were evaluated using QST before and after vibration exposure in 21 occupationally unexposed individuals. The procedure was performed twice, with a higher grip force being applied during exposure on the second occasion.

RESULTS: Vibration perception was significantly impaired after both exposures. Grip strength, perception of touch and temperature were only significantly affected after the high grip force exposure.

CONCLUSIONS: Exposure to hand-arm vibrations has acute effects on hand nerve function that are sensitive to the grip force applied during exposure.

Objective: To investigate whether low molecular organic biomarkers could be identified in blood samples from vibration exposed workers using a metabolomics.

Methods: The study population consisted of 38 metalworkers. All participants underwent a standardized medical examination. Blood samples were collected before and after work shift and analyzed with gas chromatography time-of-flight mass spectrometry. Multivariate modeling (orthogonal partial least-squares analysis with discriminant analysis [OPLS-DA]) were used to verify differences in metabolic profiles.

Results: Twenty-two study participants reported vascular symptoms judged as vibration-related. The metabolic profile from participants with vibration-induced white fingers (VWF) was distinctly separated from participants without VWF, both before and after vibration exposure.

Conclusion: Metabolites that differed between the groups were identified both before and after exposure. Some of these metabolites might be indicators of health effects from exposure to vibrations. This is the first time that a metabolomic approach has been used in workers exposed to vibrations.

Vibration white finger (VWF) is a complication from exposure to hand-arm vibrations. Poor knowledge of the pathophysiology of VWF means that making an accurate prognosis is difficult. Thus, a better understanding of VWF's pathophysiology is of importance.The purpose of this study was to investigate whether there were arterial abnormalities in the hands in patients with VWF and a positive Allen's test, using ultrasound and MRA imaging.This was a case series where arterial abnormalities in the hands were investigated in ten participants with VWF and using prolonged Allen's test (> 5 s). The participants had an average vibration exposure of 22 years and underwent Doppler ultrasound and Magnetic Resonance Angiography (MRA) to check for arterial abnormalities.The participants had VWF classified as 1-3 on the Stockholm workshop scale. Ultrasound and MRA identified vascular abnormalities in all participants, the predominant finding was missing or incomplete superficial arch. Also, stenosis was identified in four participants.This study reveals a high proportion of arterial stenosis and abnormalities in patients with VWF and a prolonged Allen's test.