Changes in upper extremity biomechanics across different mouse positions in a computer workstation

Area of Science:

• Ergonomics
• Biomechanics
• Occupational Health

Background:

• Computer workstations present ergonomic challenges.
• Mouse placement significantly impacts upper extremity biomechanics.
• Identifying optimal mouse positions is crucial for preventing musculoskeletal disorders.

Purpose of the Study:

• To compare biomechanical risk factors across various computer mouse positions.
• To evaluate the effects of different mouse placements on upper extremity posture and muscle activity.
• To determine the most ergonomically favorable mouse position for intensive computer use.

Main Methods:

• A repeated measures laboratory study involving 30 adults.
• Measurement of wrist and upper arm postures using electrogoniometers and inclinometers.
• Assessment of muscle activity in forearm and shoulder muscles via surface electromyography.

Main Results:

• The central mouse (CM) position yielded the most neutral upper extremity posture.
• The high mouse (HM) position resulted in the least neutral posture and highest muscle activity.
• The no-number-keypad (NM) mouse position slightly reduced wrist extension and improved shoulder posture compared to the standard mouse (SM) position.

Conclusions:

• The central mouse (CM) position is recommended for reducing awkward postures during mouse-intensive tasks.
• The high mouse (HM) position should be avoided due to increased biomechanical risks.
• Alternative keyboard designs (NM) may offer minor ergonomic benefits.