Persistent reduction of conduction velocity and myelinated axon damage in vibrated rat tail nerves

• Published in: Muscle & nerve 2009-06, Vol.39 (6), p.770-775
• Main Authors: Loffredo, Michael A., Yan, Ji-Geng, Kao, Dennis, Zhang, Lin Ling, Matloub, Hani S., Riley, Danny A.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; demyelination; Disease Models, Animal; Diseases of striated muscles. Neuromuscular diseases; Electric Stimulation; Electrodiagnosis; hand-arm vibration syndrome; Hand-Arm Vibration Syndrome - physiopathology; Male; Medical sciences; nerve edema; Nerve Fibers, Myelinated - pathology; Nerve Fibers, Myelinated - physiology; Neural Conduction - physiology; Neurology; occupational Raynaud disease; peripheral nerve; Peripheral Nerves - pathology; Peripheral Nerves - physiopathology; Rats; Rats, Sprague-Dawley; Reaction Time - physiology; Tail - innervation; Tail - physiopathology; Time Factors; Vibration - adverse effects; Wallerian Degeneration - etiology; Wallerian Degeneration - pathology; Wallerian Degeneration - physiopathology
• ISSN: 0148-639X; 1097-4598
• DOI: 10.1002/mus.21235

Prolonged hand‐transmitted vibration exposure in the workplace has been recognized for almost a century to cause neurodegenerative and vasospastic disease. Persistence of the diseased state for years after cessation of tool use is of grave concern. To understand persistence of vibration injury, the present study examined recovery of nerve conduction velocity and structural damage of myelinated axons in a rat tail vibration model. Both 7 and 14 days of vibration (4 h/day) decreased conduction velocity. The decrease correlated directly with the increased percentage of disrupted myelinated axons. The total number of myelinated axons was unchanged. During 2 months of recovery, conduction velocity returned to control level after 7‐day vibration but remained decreased after 14‐day vibration. The rat tail model provides insight into understanding the persistence of neural deficits in hand–arm vibration syndrome. Muscle Nerve, 2009