Innovating the wheeled Zimmer, one of the most prescribed indoor walking frames.

BACKGROUND

Counter-intuitively, a systematic review identified general walking aid use to be a risk factor for falling; some research even linked falls directly to use of walking aids. Hence walking aids’ effectiveness remains suboptimal. Yet a lack of innovation, especially with regard to indoor walking frames, persists: the front-wheeled Zimmer frame has not changed in design for decades. It was the aim of this work to completely re-think and innovate indoor walking frame design for enhanced user stability and mobility. New features include: 1) swivel wheels at the front to help turning, but which self-align straight during straight line walking, 2) glider feet at the rear to go over thresholds, 3) brakes inside the glider feet to prevent the frame from “running away”.

METHODS

Four proof-of-concept studies investigated the standard versus the new frame design:

Study 1. A gait lab-based study quantified stability (9 healthy older adults, walking repeated trials).

Study 2. A care-home based study investigated unstable usage patterns and body weight transfer (9 older frame users).

Study 3. An interview study investigated perceptions of 7 frame users regarding usability and safety.

Study 4. A clinical trial assessed safety and efficacy of use (10 clinicians, 10 inpatients, 8 outpatients, use of a questionnaire).

RESULTS

The novel frame increased stability during performance of complex everyday tasks (p<0.05). It also facilitated safer usage patterns whilst providing greater and more continuous body weight support. Users found the new design enjoyable; “That’s better than what I am using at the moment” and “I enjoyed using this one {new frame} compared to the other.” and clinicians perceived it to be safe and effective and hence more usable.

CONCLUSIONS

The four studies combined let us conclude that the new frame design is an improvement on the status quo.