Segmental nerve conduction velocity in vibration-exposed shipyard workers

Abstract

Reduced SNCV in the digits may be a consequence of industrial exposure to vibration. Each sensory nerve segment appeared to have a different characteristic velocity and different pattern of association with skin temperature. There are differences between median and ulnar nerve segments, with potentially important consequences when standard distances are used to assess wrist-digit velocity.

The effect of different warming methods on sensory nerve conduction velocity in shipyard workers occupationally exposed to hand–arm vibration

“…Several investigators have also described a distal pattern of delayed sensory nerve conduction velocity (SNCV), localized to the digits (Sakakibara et al 1994(Sakakibara et al , 1998Hirata et al 2002). The methodology and our results from a baseline study of segmental SNCV in vibration-exposed shipyard workers were the Wrst phase of an international exposure-response study on HAV, and were previously reported in this journal (Cherniack et al 2004a) and seemed to conWrm the earlier reports. SigniWcant digital SNCV reduction was observed.…”

“…In 2001, the IUG and the larger exposed group (EG) were demographically similar in age and years of employment (Cherniack et al 2004a). However, as Table 2 demonstrates, the nine subjects from the IUG who were tested in 2001, but had dropped out in 2004 (column 2), were signiWcantly older by 7.36 years than those who were tested in 2001 and retested in 2004 (column 3).…”

“…In our earlier paper, we addressed pertinent issues around segmental nerve conduction studies (Cherniack et al 2004a). Perhaps the most problematic is obtaining reliable SNCV measurements over short segments.…”

“…The comparative over-representation of disease may invite spurious assignment of causation due to confounding factors that contribute to morbidity. When the prevalent abnormality nears 50%, as occurred in this working group in 2001, external referent comparisons are likely to be to obscure particular to sub-groups within exposed cohorts (Cherniack et al 2004a). Accordingly, in 2001 a small internal nonexposed comparison group (n = 28) was selected from the larger cohort.…”

“…The conversion to velocity provides a translatable value for segments that lack normal values for latency. A more detailed description of the technique can be found in Cherniack et al (2004a).…”