Ergonomic comparison between a 'right angle' handle style and standard style paint brush: An electromyographic analysis

- A right angle handle paint brush has no added ergonomic advantage over a standard type handled brush in modifying muscle activity.
- A right angle handle paint brush handle has no added benefit in reducing muscle fatigue.
- Individuals have a preferred painting technique (ie. grip) that they when painting and changing the shape of the brush handle does not affect it despite handle design; explicit instruction may be required to reap benefits of ergonomic design.

BackgroundEpidemiologic studies have consistently demonstrated a strong positive association between repetition and “occupational overuse syndromes” (OOS). The repetitive nature of painting then can predispose many people to these disorders.ObjectiveThe purpose of this study was to conduct an electromyographic analysis (EMG) comparing a right angle handle paint applicator with a commonly used, equal quality standard handle paint brush.MethodA randomized cross over repeated measures design was implemented where 30 volunteers were randomly given a paint brush handle type while muscle activity (EMG) was recorded from eight upper limb muscles groups. Subjects were their own controls returning within one week to perform the same painting activity with the other paint brush handle type. ANOVA with repeated measures was used to analyze the EMG data among muscles between the two painting trials.ResultsEMG analysis revealed that there was no difference in EMG activity or median frequency between the two types of paint brush handles in the eight muscles studied (p > 0.05).ConclusionA right angle handle has no added ergonomic advantage in modifying muscle activity or decreasing muscle fatigue over a commonly used standard handle paint brush in people without injury. It was suggested that the right angle style brush may not prevent OOSs from occurring, although there still could be a decrease risk of injury based on the posture used when gripping the brush handle. It must be emphasized, however, that this study's results cannot be extrapolated to people who already have an OOS and need a device to prevent further injury and pain. Further study is needed.