Changes in the posterior interosseous nerve - are they related to carpal tunnel syndrome rather than vibration?
Tim Davis, NHS
21 January 2015
I read this review article with interest but am concerned that the authors’ conclusion that use of hand-held vibrating tools causes damage to the posterior interosseous nerve is correct.
The authors cite the work of Stromberg et al. (1997) who compared posterior interosseous nerve biopsies taken from 10 men who used hand-held vibrating machinery with ones taken from 12 matched male necropsy controls with no history of vibration exposure. They observed demyelination and other changes in the biopsies from the vibration-exposed and wondered whether demyelination might be the primary lesion in neuropathy caused by vibration exposure. Others also suggest that this demyelination at the wrist level may predispose vibration exposed workers to develop carpal tunnel syndrome.
However vibration-exposure was not the only difference between the study group and the control group. This is as nine of the 10 vibration-exposed subjects also had carpal tunnel syndrome, and their posterior interosseous nerve biopsies were taken during carpal tunnel decompression surgery. Thus it is possible that the differences between the posterior interosseous nerve biopsies in the two groups were due to the presence of carpal tunnel syndrome, rather than the vibration exposure.
More recently Thomsen et al. (2009) have studied posterior interosseous nerve biopsies taken from diabetics and non-diabetics with carpal tunnel syndrome and compared them to a control group which contained many of the necropsy samples which were also used as controls in Stromberg et al.’s study. Thomsen et al. (2009) found significantly lower myelinated nerve-fibre densities in the posterior interosseous nerve biopsies from both the diabetics and non-diabetics with carpal tunnel syndrome.
Does this not suggest that the demyelination observed by Stromberg et al. (1997) was probably due to the fact that all but one of their vibration-exposed group also suffered with carpal tunnel syndrome? A study of posterior interosseous nerve biopsies taken from subjects who use hand-held vibrating tools but do not suffer with carpal tunnel syndrome is needed to demonstrate that these tools are associated with demyelination and other nerve changes at the wrist level.
Yours sincerely
Professor T R C Davis
Consultant Hand & Orthopaedic Surgeon, Queens Medical Campus, Nottingham University Hospitals
Stromberg T, Dahlin LB, Brun A, Lundborg G: Structural nerve changes at wrist level in workers exposed to vibration. Occup Environ Med 1997, 54:307-311.
Thomsen NO, Mojaddidi M, Malik RA, Dahlin LB: Reduced myelinated nerve fibre and endoneurial capillary densities in the forearm of diabetic and non-diabetic patients with carpal tunnel syndrome. Acta Neuropathol 2009, 118:785-791.
Journal of Occupational Medicine and Toxicology
Changes in the posterior interosseous nerve - are they related to carpal tunnel syndrome rather than vibration?
21 January 2015
I read this review article with interest but am concerned that the authors’ conclusion that use of hand-held vibrating tools causes damage to the posterior interosseous nerve is correct.
The authors cite the work of Stromberg et al. (1997) who compared posterior interosseous nerve biopsies taken from 10 men who used hand-held vibrating machinery with ones taken from 12 matched male necropsy controls with no history of vibration exposure. They observed demyelination and other changes in the biopsies from the vibration-exposed and wondered whether demyelination might be the primary lesion in neuropathy caused by vibration exposure. Others also suggest that this demyelination at the wrist level may predispose vibration exposed workers to develop carpal tunnel syndrome.
However vibration-exposure was not the only difference between the study group and the control group. This is as nine of the 10 vibration-exposed subjects also had carpal tunnel syndrome, and their posterior interosseous nerve biopsies were taken during carpal tunnel decompression surgery. Thus it is possible that the differences between the posterior interosseous nerve biopsies in the two groups were due to the presence of carpal tunnel syndrome, rather than the vibration exposure.
More recently Thomsen et al. (2009) have studied posterior interosseous nerve biopsies taken from diabetics and non-diabetics with carpal tunnel syndrome and compared them to a control group which contained many of the necropsy samples which were also used as controls in Stromberg et al.’s study. Thomsen et al. (2009) found significantly lower myelinated nerve-fibre densities in the posterior interosseous nerve biopsies from both the diabetics and non-diabetics with carpal tunnel syndrome.
Does this not suggest that the demyelination observed by Stromberg et al. (1997) was probably due to the fact that all but one of their vibration-exposed group also suffered with carpal tunnel syndrome? A study of posterior interosseous nerve biopsies taken from subjects who use hand-held vibrating tools but do not suffer with carpal tunnel syndrome is needed to demonstrate that these tools are associated with demyelination and other nerve changes at the wrist level.
Yours sincerely
Professor T R C Davis
Consultant Hand & Orthopaedic Surgeon, Queens Medical Campus, Nottingham University Hospitals
Stromberg T, Dahlin LB, Brun A, Lundborg G: Structural nerve changes at wrist level in workers exposed to vibration. Occup Environ Med 1997, 54:307-311.
Thomsen NO, Mojaddidi M, Malik RA, Dahlin LB: Reduced myelinated nerve fibre and endoneurial capillary densities in the forearm of diabetic and non-diabetic patients with carpal tunnel syndrome. Acta Neuropathol 2009, 118:785-791.
Competing interests
None