Hand dominance effect on median and ulnar sensory evoked amplitude and latency in asymptomatic workers.
Arch Phys Med Rehabil 1996 May; 77(5):473-476
The influence of hand dominance on grip strength, and median and ulnar sensory evoked responses was investigated among asymptomatic workers. A total of 224 workers of the automobile parts manufacture, furniture manufacture, paper container manufacture, and clerical industries were tested. Of the workers examined, 87% were right hand dominant. The left handed group was slightly younger than the right handed group. For the right handed workers, the median sensory amplitudes were 38.6 microvolts (microV) on the left and 34.6microV on the right, whereas the ulnar sensory amplitudes were 34.4microV on the left and 33.0microV on the right. The left hand of right handed workers exhibited a significantly elevated median sensory amplitude. The sensory latencies did not differ between the right and left sides. For the left handed workers, neither the median nor the ulnar sensory amplitudes differed according to side. However, the median and ulnar sensory latencies of the left hand were significantly faster than those of the right. The median and ulnar amplitudes of the right and left hands were correlated, with coefficients of 0.83 and 0.85, respectively. The median and ulnar peak latencies of the left and right hands were correlated, both with a coefficient of 0.83. Correlation coefficients of 0.96 and 0.93 described the relationships between right and left grip strength and right and left pinch strength, respectively. Among right hand dominant workers, the grip and pinch strengths of the right hand were significantly higher than those of the left. In left hand dominant workers, both hands exerted similar strengths. The authors attribute the differences in the sensory evoked amplitudes of the right and left hands in right handed workers to differential exposures to repetitive trauma. Left handed workers are more likely to utilize both hands than are right handed workers.
NIOSH-Publication; NIOSH-Grant; Grants-other; Cumulative-trauma-disorders; Nerve-function; Humans; Peripheral-nervous-system; Neurophysiological-effects; Office-workers; Industrial-factory-workers
Robert A. Werner, MD, Physical Medicine and Rehabilitation Service, VA Medical Center, 2215 Fuller Road (117), Ann Arbor, M148105
Archives of Physical Medicine and Rehabilitation
University of Michigan at Ann Arbor, Ann Arbor, Michigan