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Updated: Aug 7, 2026

Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
Shoulder joint kinetics and pathology in manual wheelchair users
Jennifer L Mercer1, Michael Boninger, Alicia Koontz
1Human Engineering Research Laboratories, 151R1-H, VA Rehabilitation Research and Development Center, VA Pittsburgh Healthcare Systems, 7180 Highland Drive, PA 15206, USA.
Background:
Manual wheelchair users rely heavily on their upper limbs for independent mobility which likely leads to a high prevalence of shoulder pain and injury. The goal of this study was to examine the relationship between shoulder forces and moments experienced during wheelchair propulsion and shoulder pathology.
Methods:
Kinetic and kinematic data was recorded from 33 subjects with paraplegia as they propelled their wheelchairs at two speeds (0.9 and 1.8 m/s). Shoulder joint forces and moments were calculated using inverse dynamic methods and shoulder pathology was evaluated using a physical exam and magnetic resonance imaging scan.
Findings:
Subjects who experienced higher posterior force (Odds Ratio (OR)=1.29, P=0.03), lateral force (OR=1.35, P=0.047), or extension moment (OR=1.35, P=0.09) during propulsion were more likely to exhibit coracoacromial ligament edema. Individuals who displayed larger lateral forces (OR=4.35, P=0.045) or abduction moments (OR=1.58, P=0.06) were more likely to have coracoacromial ligament thickening. Higher superior forces (OR=1.05, P=0.09) and internal rotation moments (OR=1.61 P=0.02) at the shoulder were associated with increased signs of shoulder pathology during the physical exam.
Interpretation:
Specific joint forces and moments were related to measures of shoulder pathology. This may indicate a need to reduce the overall force required to propel a wheelchair in order to preserve upper limb integrity. Potential interventions include changes to wheelchair setup, propulsion training, or alternative means of mobility.

