Lina Lander, MSc¹, Ron House, MD FRCPC², Wendy Lou, PhD², Jim Purdham, PhD³, and Michael Wills, MD FRCPC². (1) Department of Environmental Health, Harvard School of Public Health, 665 Huntington Ave, Mailbox 392, Boston, MA 02115, 617-566-0803, ilander@hsph.harvard.edu, (2) Graduate Department of Public Health Sciences/Gage Occupational and Environmental Healt Unit, University of Toronto, 223 College Street, Toronto, ON M5T 1R4, Canada, (3) Gage Occupational and Environmental Health Unit, Dept Public Health Sciences, University of Toronto, 223 College Street, Toronto, ON M5T 1R4, Canada

Background: Hand-Arm Vibrations Syndrome (HAVS) is associated with occupational exposure to hand-held vibrating tools and includes vascular, neurological, and musculoskeletal components. The Stockholm Neurological Scale (SNS) is used to classify the neurological impairment severity and includes a range of subjective impairment levels based on symptom reporting. While objective impairment tests are preferred, they have not been well evaluated for their association with physical examination and subjective symptoms reports, such as those measured with the SNS. Objectives: The SNS ratings were evaluated to determine their association with the results of current perception threshold tests, nerve conduction studies, and other clinical, occupational, and demographic data abstracted from chart review in subjects clinically assessed for HAVS. Methods: Detailed physical examinations and special tests including nerve conduction and current perception threshold studies were done on 162 subjects attending an occupational medicine clinic in an urban hospital in Toronto, Ontario. SNS classification was blinded to the results of these objective tests. Results: Analysis indicated that vibration exposure in total hours (p =0.002 – right hand; p =0.028 – left hand) and current perception threshold results (p =0.369 – right hand; p = 0.002 – left hand) were significant predictors of the SNS ratings for at least one hand. Stockholm Vascular and Neurological Scales were significantly associated for each hand (p<0.0001 – right hand; p<0.0001 – left hand). Conclusions: Current perception threshold tests alone are insufficient to provide impairment ratings. These tests, however, may be used to aid in the Stockholm Neurological Scale impairment classification of patients with Hand-Arm Vibration Syndrome.

Learning Objectives:

• Describe HAVS, its manifestation, and SNS used to classify the impairment
• Explain objective tests used to aid in the diagnosis
• Describe the association between the SNS, special tests, and other clinical, occupational, and demographic data.

Keywords: Occupational Disease, Workplace Safety

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.