Vertical force and wrist deviation angle when using a walker to stand up and sit down

Area of Science:

• Gerontology
• Biomechanics
• Rehabilitation Engineering

Background:

• Walkers primarily assist elderly individuals with lower limb weakness.
• The impact of walker use on upper limb biomechanics, specifically wrist function, is under-investigated.
• Daily activities like standing and sitting are crucial for elderly independence.

Purpose of the Study:

• To investigate wrist deviation and vertical forces in elderly individuals using walkers for sit-to-stand and stand-to-sit transitions.
• To identify potential design flaws in standard walker handles that may affect wrist posture.

Main Methods:

• Sixty-four elderly volunteers (mean age 80.22) participated.
• Data collected using four load cells and a twin-axis wrist goniometer.
• Analyzed wrist deviation (ulnar/radial, flexion/extension) and vertical ground reaction forces during sit-to-stand and stand-to-sit maneuvers with walker assistance.

Main Results:

• Significant wrist angle deviation was observed during walker-assisted sit-to-stand and stand-to-sit.
• Right-hand dorsiflexion was greater than left-hand dorsiflexion.
• Males generated significantly greater vertical forces.
• Experienced walker users showed greater ulnar deviation when sitting and greater dorsiflexion when standing.

Conclusions:

• Standard walker horizontal handles can induce undesirable wrist deviations in elderly users.
• Improvements in walker handle design are recommended to mitigate wrist strain and enhance user comfort and safety.
• Further research into upper limb biomechanics during assistive device use is warranted.