Movement science task determinants of wheelchair propulsion

1. Task Determinants of Wheelchair
Propulsion
Kacie Washburn
Samantha Jensen

2. Push Phase
• Apply a grip to the pushrim
• Stabilize base of support
• Transfer a force from the upper extremity to
the pushrim

3. 1. Apply a grip force to the pushrim

4. High Impact Force on the Wrist

5. 2. Stabilize base of support

6. Postural Control

7. 3. Transfer a force from UE to pushrim

8. STYLES F O R C E R E Q U I R E D
0.56 Newtons
0.58 Newtons
0.45 Newtons

9. Contact Angle

10. Surface Effects
Hardwood Carpet Ramp
0.45 Newtons 0.54 Newtons 0.52 Newtons

11. Peak Torque occurs at 30-40
degrees into the push phase

12. Push phase Kinematics
Early Push Phase:
Late Push Phase:
ROM Muscles
Shoulder Flexion Anterior Deltoid
Elbow Extension Triceps
Wrist Radial
Deviation
Extensor Carpi
Radialis
ROM Muscles
Shoulder Flexion Anterior
Deltoid,
Pectoralis
Elbow Extension Triceps
Wrist Ulnar
Deviation
Extensor Carpi
Ulnaris

13. Recovery Phase
Propulsion
Push Phase
Recovery Phase
• Release the grip from the pushrim
• Return the upper extremity to its original
position

14. 4. Release Grip

15. 5. Return to Original Position

16. Recovery Kinematics
Early Recovery Phase:
Late Recovery Phase:
ROM Muscles
Shoulder Extension Posterior
Deltoid,
Triceps
Elbow Extension Triceps
Wrist Neutral N/A
ROM Muscles
Shoulder Extension Posterior
Deltoid,
Triceps
Elbow Flexion Biceps
Wrist Radial
Deviation
Extensor
carpi radialis

17. Efficiency: Work per Metabolic Energy
5-10%
20-25%
h =
EnergyOutput
EnergyInput
x100%

18. Wheelchair Fit
A:
angle too small
C:
angle is too large
B:
correct angle = 100-120

19. Semicircular Propulsion Style

20. Think About Swimming…