Characterization of compensatory trunk movements during prosthetic upper limb reaching tasks

Area of Science:

• Biomechanics
• Rehabilitation Science
• Prosthetics

Background:

• Upper limb amputation presents functional challenges.
• Prosthesis users often adopt altered movement strategies.
• Understanding compensatory movements is crucial for effective rehabilitation.

Purpose of the Study:

• To quantify trunk compensatory movements in upper limb prosthesis users during functional reaching.
• To compare trunk kinematics between prosthesis users and unimpaired individuals.

Main Methods:

• Three-dimensional motion analysis was employed.
• Participants included transhumeral and transradial prosthesis users (n=10) and controls (n=10).
• Tasks simulated daily activities like donning a cap and sorting clothes.

Main Results:

• Prosthesis users demonstrated significantly increased trunk range of motion in all directions and tasks (P≤.03).
• Shoulder and elbow path distances were also greater in prosthesis users (P<.01).
• Compensatory movements were observed even in transradial users with an intact elbow.

Conclusions:

• Altered arm structure necessitates different motor control strategies.
• Trunk displacement compensates for the loss of distal arm/hand function.
• These compensatory movements may impact prosthesis acceptance and can be addressed through rehabilitation.