Impaired Manual Dexterity and Neuromuscular Dysfunction in Patients with Hand-Arm Vibration Syndrome

Abstract

Manual dexterity and hand functional difficulties in daily life in hand-arm vibration syndrome (HAVS) were investigated in 29 male patients with HAVS and 30 male controls without occupational exposure to hand-arm vibration. Manual dexterity was assessed by measuring the performance time of picking up and transferring 30 red beans, one by one, from one plate to another. Vibrotactile perception thresholds at 125 Hz and grip strength were also examined. Hand functional difficulties in daily life were surveyed with a questionnaire. The HAVS patients had an increased vibrotactile threshold, decreased grip strength, and low performance in transferring beans. Low performances with transfer times over 53 s (2SD from the mean in the controls) were found in 66% of the HAVS patients and 3% of the controls. Bean transfer times in the patients were correlated with an increasing vibrotactile threshold and decreasing grip strength. The transfer times of the patients were also associated with hand functional difficulties such as picking up coins, turning the pages of a newspaper, buttoning clothes, and pouring from a teapot. The patients with a prolonged transfer time over 60 s (3SD from the mean in the controls) were most likely to have hand functional difficulties. The present findings suggest that measurement of the bean transfer time will serve to assess manual dexterity among HAVS patients, and that impaired manual dexterity in patients may be associated with impaired sensory feedback and muscular dysfunction in the fingers and hands.

Assessment of coarse and fine hand motor performance in asymptomatic subjects exposed to hand-arm vibration

“…Our findings are consistent with the results reported in other studies (6,7,21,22) which found impairment to manual dexterity in groups of workers exposed to hand transmitted vibration. However, our findings could not be directly compared with these results as most of the published studies deal with developed HAVS cases (6,7,31), rarely discussing the biological processes of damage/repair that are relevant for the The decreased grip strength has also been reported (6,8,9).…”

“…Manual dexterity loss is a known consequence of vibration exposure (6,7,21,22). It results from (23,24).…”

“…It is caused by the altered vascular response in people working with vibrating power tools (4) and is diagnosed using the cold provocation (CP) test (5). Long-term use of vibrating tools may also induce neural problems, resulting in impaired dexterity and fine manipulation ability, numbness, paresthesia, reduced tactile discrimination, and tendency to drop tools (6). The impaired manual dexterity may be associated with reduced sensory feedback and muscular dysfunction in the fingers and hands (6,7).…”

“…Long-term use of vibrating tools may also induce neural problems, resulting in impaired dexterity and fine manipulation ability, numbness, paresthesia, reduced tactile discrimination, and tendency to drop tools (6). The impaired manual dexterity may be associated with reduced sensory feedback and muscular dysfunction in the fingers and hands (6,7). Hand muscle weakness, particularly affecting the long finger flexors and affecting grip strength was also found (6,8,9).…”

“…The impaired manual dexterity may be associated with reduced sensory feedback and muscular dysfunction in the fingers and hands (6,7). Hand muscle weakness, particularly affecting the long finger flexors and affecting grip strength was also found (6,8,9).…”