Wheelchair Design and Measurement

Key Considerations

• User Size: Essential to consider the size of the user when designing a wheelchair.
• Anthropometry: General and special needs considerations.
  • Sit width: Should be narrow enough but not cause stress on the hips (add 2 inches to hip and thigh measurement).
  • Sit depth: Measure from popliteal to buttocks, subtract 2 inches for knee bending.
  • Back height: Measure up to scapula, subtract 1-2 inches based on user needs.
  • Chest width: Depends on backrest design.
  • Seat height: Facilitate 90-90-90 degrees at hips, knees, and ankles. Footrest should have a 2-inch clearance from the floor.
  • Armrest: Allow shoulders to relax with elbows flexed at 90 degrees.

General Sizing

• Posture Phenomena: Understanding common posture issues like posterior pelvic tilt, anterior pelvic tilt, and trunk lordosis.
  • Causes and solutions for each posture problem.
  • Posterior pelvic tilt: Low tone, tight hamstrings, sliding forward.
    • Solutions: Adjust the backrest, add support.
  • Anterior pelvic tilt and uneven pelvis: Add support or use Newton's Law for adjustment.
  • Fixed posture problems: May require high-tech solutions or surgical interventions.
  • Trunk lordosis: Emphasize the 90-90-90 rule, use lower trunk support.

Practical Tips

• Person's Needs: Consider physical, psychological, and financial aspects.
• Measurement Principles: Focus on 90-90-90 degrees rule for posture.
  • Less external support is better to encourage natural body use.

Case Examples

• Review images and scenarios to evaluate posture and wheelchair design efficacy.
  • Analyze posture and make necessary adjustments.

Summary

• Ensure correct measurements and support to provide comfort and proper posture.
• Always consider the individual needs and avoid over-reliance on external support unless essential.