A Comparison of Examination Equipment Used During Common Clinical Ophthalmologic Tasks

OCCUPATIONAL APPLICATIONS Ophthalmologists and other eye-care physicians frequently use clinical examination equipment that restricts access to patients and requires the adoption of sustained, non-neutral working postures of the neck and shoulders. The use of ergonomic principles in the design of examination equipment could help reduce these physical demands, which may be partly responsible for the high prevalence of neck and shoulder pain among ophthalmologists. This study compared the effects of a set of this alternative “ergonomic” equipment to a set of conventional equipment on measures of neck and shoulder muscle activity and upper arm posture during simulations of common clinical ophthalmologic tasks. Results suggested that some aspects of the alternative equipment may help reduce exposures to sustained, non-neutral working postures of the neck and shoulder among ophthalmologists. Ophthalmologists and other eye-care physicians may consider implementing similar alternative equipment interventions into their practices. TECHNICAL ABSTRACT Background: Ophthalmologists report a high prevalence of work-related musculoskeletal symptoms, particularly of the neck and shoulders. Improving the design of equipment used in the clinical environment may reduce exposures to physical risk factors (e.g., sustained muscular exertions and non-neutral postures) associated with neck and shoulder pain among ophthalmologists. Purpose: This study compares estimates of neck and shoulder muscle activity and upper arm posture during use of conventional and alternative examination equipment common in clinical ophthalmologic practice. Methods: Fifteen ophthalmologists performed one mock clinical examination using conventional equipment and one mock clinical examination using alternative equipment with the potential to reduce exposure to sustained muscular exertions and non-neutral upper arm postures. The alternative equipment included a slit lamp biomicroscope with inclined viewing oculars, adjustable elbow supports, and a wider tabletop with more room for supporting the arms in comparison to the conventional slit lamp biomicroscope. A wireless binocular indirect ophthalmoscope was also evaluated that had a more even weight distribution than the conventional design. Measurements of upper trapezius and anterior deltoid muscle activity, upper arm posture, and perceived usability were used to compare the conventional and alternative equipment. Results: In comparison to the conventional slit lamp biomicroscope, the alternative slit lamp biomicroscope led to (i) 12% to 13% reductions in upper trapezius muscle activity levels, (ii) a 9% reduction in left anterior deltoid muscle activity levels, and (iii) a 15% reduction in the percentage of work time spent with the left upper arm elevated in positions greater than 60º. In addition, participants rated the comfort and adjustability of both the alternative slit lamp biomicroscope and binocular indirect ophthalmoscope more favorably than the conventional equipment. Conclusions: The results suggest that the alternative slit lamp biomicroscope may help to reduce overall muscular demands and non-neutral postures of the neck and shoulder region among ophthalmologists.