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Biomechanical analysis of upper extremity risk in Sign Langauge Interpreting

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Abstract

Upper extremity cumulative trauma distorders (UECTD) have been identified as an occupational health problem in professional Sign Language Interpreters (SLI). A previous study of UECTD in SLI has indicated significant differences between interpreters working with pain and those working without pain. This earlier research focused on gross measures of hand/wrist movement, work/rest cycles, and deviations from an optimal work envelope. The present paper describes a detailed biomechanical analysis of wrist and forearm activity associated with SLI. This assessment included forearm (flexion and extension) and wrist (flexion/extension and radial/ulnar deviation) measures of movement frequency, counts of individual motion, joint movement velocities and accelerations as well as range of motion. The analyses revealed that the postures required for interpreting result in the signing hand frequently held in a fully pronated position, with the palm facing out. The wrist was most frequently in an ulnar deviation and/or extension while the elbow was flexed more than 90° and held in close to the body with the fingers pointing up. The frequency of motions for the forearm and wrist were observed to be 270 per minute (4.5 Hz), which is equivalent to 13,600 per 50 minute lecture hour. The mean absolute joint movement velocity and acceleration values were relatively high in contrast to industrial jobs with wrist and forearm accelerations between 34,754 degreees/sec2 and 36,046 degrees/sec2, respectively. The findings from this biomechanical analysis indicates that SLI can involve highly repetitive, awkward movements with significant accelerations of the hand and wrist. Such job characteristics may predispose interpreters to upper extremity CTD-related disorders.

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References

  1. Bureau of Labor Statistics. Occupational Injuries and Illnesses in the United States by Industry, 1989. U.S. Department of Labor, Bureau of Labor Statistics, Bulletin 2379, U.S. Government Printing Office, Washington, D.C.

    Google Scholar 

  2. Armstrong TJ. Ergonomics and cumulative trauma disorders.Hand Clin 1986; 2(3): 553–565.

    Google Scholar 

  3. Silverstein BA, Fine LJ, Armstrong TJ. Hand wrist cumulative disorders in industry.Brit J Indust Med 1986; 43: 779–784.

    Google Scholar 

  4. Silverstein BA, Fine LJ, Armstrong TJ. Occupational factors and carpal tunnel syndrome.Am J Indust Med 1987; 11: 343–358.

    Google Scholar 

  5. Meals RA, Payne W, Gaines R. Functional demands and consequences of manual communication.J Hand Surg 1988; 13(5): 686–691.

    Google Scholar 

  6. Cohn L, Lowry RM, Hart S. Overuse syndromes of the upper extremity in interpreters for the deaf.Orthopedics 1990; 13(2): 207–209.

    Google Scholar 

  7. Sanderson G. Overuse syndrome among sign language interpreters.J Interpret 1987; 4: 73–78.

    Google Scholar 

  8. Stedt JD. Carpal tunnel syndrome: The risk to educational interpreters.Am Ann Deaf 1989; 134: 223–226.

    Google Scholar 

  9. Feuerstein M, Fitzgerald TD. Biomechanical factors affecting upper extremity cumulative trauma disorders in sign language interpreters.J Occup Med 1992; 34: 1–8.

    Google Scholar 

  10. Putz-Anderson V.Cumulative trauma disorder: A manual for musculoskeletal disease of the upper limbs. New York: Taylor and Francis Publishers, 1988.

    Google Scholar 

  11. Schoenmarklin RW, Marras WS.Validation of a Hand/Wrist Electromechanical Goniometer. Proceedings of the Human Factor Society 33rd Annual Meeting, 1989, pp. 718–722.

  12. Schoenmarklin RW, Marras WS.A Dynamic Biomechanical Model of the Wrist Joint. Proceedings of the Human Factors Society 34th Annual Meeting, 1990, pp. 805–809.

  13. Schoenmarklin RW, Marras WS.Quantification of Wrist Motion and Cumulative Trauma Disorders in Industry. Proceedings of the Human Factors Society 35th Annual Meeting, 1991; pp. 838–842.

  14. Feuerstein M, Jones R.Comprehensive Multidisciplinary Approach to Evaluation, Rehabilitation and Prevention of Repetitive Motion Disorders in Sign Language Interpreters. Final report, University of Rochester School of Medicine and Dentistry, Center for Occupational Rehabilitation, Rochester, New York.

  15. Drury CG. A biomechanical evaluation of the repetitive motion injury potential of industrial jobs.Sem Occup Med 1987; 2(1): 41–49.

    Google Scholar 

  16. NASA.Anthropometry source book. NASA Reference Publication 1024, 1978.

  17. Serway RA.Physics for scientists and engineers (2nd Ed.). New York: Saunders College Publishing, 1986.

    Google Scholar 

  18. Feldman R, Goldman R, Keyserling W. Peripheral nerve entrapment syndromes and ergonomic factors.Am J Indust Med 1983; 4: 661–681.

    Google Scholar 

Download references

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Shealy, J., Feuerstein, M. & Latko, W. Biomechanical analysis of upper extremity risk in Sign Langauge Interpreting. J Occup Rehab 1, 217–225 (1991). https://doi.org/10.1007/BF01073458

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