Sahika Vatan Korkmaz

A Comparison of Computer Workstation Adjustments Made by Users Following Web-Based Instructions and Those of an Ergonomics Professional

Computer use and posture has been linked to musculoskeletal disorders. Web-based tools offer a way for users in large organizations to perform an initial assessment and routine adjustment of their workstations, allowing the ergonomist to focus on more detailed cases. Twelve male and eight female subjects used a web-based tool to adjust two standard workstations. The tool presented information using text, animation and color coding to accommodate as many learning styles as possible. Afterwards, an ergonomist, blinded to the adjustments made previously, adjusted each workstation for the subject. Subject adjustments agreed with the ergonomists for chair height, seat pan depth, armrest height, monitor depth and keyboard tray height with moderate correlation values and mean errors of less than 1.35 cm. The results indicate computer users are able to adjust their own workstations following this type of web-based instruction.

Comparison of Spinal Loads in Kneeling and Standing Postures during Manual Materials Handling

Kneeling in a restricted posture during manual materials handling has been associated with increased risk of low back pain. Little is known about the effect of kneeling posture on spinal loads. The purpose of this study was to compare differences in spinal loading between kneeling and standing postures for lifting tasks. Twelve subjects asymmetrically lifted luggage of three weights to three heights from floor while kneeling. Three subjects also performed the same tasks from waist height while standing. An adapted free-dynamic EMG-assisted biomechanical model was used to calculate spinal loads. Statistical analysis showed that there was no difference in compression between kneeling and standing (p=0.9605), but kneeling resulted in increased anterior-posterior and lateral shear forces on the lumbar spine (p =0.0002 and p<0.0001, respectively). Spinal loading changes while kneeling in a restricted posture may increase the risk of low back injury and must be considered in ergonomic job design.

Teaching Healthy Computing Skills to High School Students via Participatory Ergonomics

When todays students graduate from college and start their first job, many have close to twenty years of computer use exposure and some of them also have discomfort associated with this exposure. This discomfort may be due, in part, to a lack of training, from schools or other sources, in healthy computing habits (such as taking breaks, reducing awkward postures and postural fixity, etc.). A long-term goal of this line of research is to improve the health of students. In this study students were introduced to the concept and principles of healthy computing. The specific aim of this study was to recruit a small group of students to learn, in a participatory fashion, about healthy computing and then to assist them to develop means for effectively conveying their knowledge to other students. The objective of this paper is to explain the methodology that was utilized in the study and to provide evidence of its effectiveness.

Developing a Non-Human Primate Experimental Model for Studying Carpal Tunnel Syndrome

This study investigated changes in median nerve conduction velocity (NCV) over several weeks of exposure to a voluntary, moderately forceful, repetitive pinching task performed for food rewards by a small sample of young adult female monkeys (Macaca fascicularis). Sensory NCV, derived from peak latency, decreased significantly in the working hands of three of the four subjects. The overall decline in NCV was 25–31% from baseline. There was no decrease in NCV in the non-working hands. The results demonstrate a temporally unambiguous relationship between exposure to a moderately forceful, repetitive manual task and development of median mononeuropathy. This study contributes to the pattern of evidence of a causal relationship between manual work and significant median nerve impairment (carpal tunnel syndrome in humans). In the future, such a model could be used to assess dose-response relationships between physical risk factors and carpal tunnel syndrome.