Innovation of a Rehabilitation Chair for Elderly People with Knee Osteoarthritis

Abstract

The research on Innovation of a Rehabilitation Chair for Elderly People with Knee Osteoarthritis aimed to (1) study and design a rehabilitation chair specifically for elderly individuals with knee osteoarthritis, (2) test the usability and effectiveness of the chair, and (3) transfer knowledge and innovation to relevant organizations for practical application in elderly rehabilitation. The study focused on developing two chair models: a rehabilitation chair and a sit-to-stand assistive chair, both designed to reduce the limitations of standing up and sitting down, enhance safety, and support rehabilitation in daily life. The conceptual framework was based on ergonomics, with both engineering performance tests and user experience evaluations. This was conducted as experimental research, designing dimensions and structures appropriate to elderly body proportions.

The innovation included a manual mechanism for knee and ankle flexion–extension exercises and a spring-assisted arm support system to facilitate safe sit-to-stand movements. The sample group consisted of nine elderly patients with knee osteoarthritis from Surin Hospital, Tambon Tabo Health Promoting Hospital, and Tambon Khok Sa-at Health Promoting Hospital, selected through purposive sampling, along with three expert evaluators. Research instruments included the prototype chair, expert evaluation forms, and in-depth interviews. Data analysis employed descriptive statistics and content analysis.

The expert evaluation results indicated the chair demonstrated very high efficiency in all aspects: structural strength (Mean = 4.87, SD = 0.21), ease of use (Mean = 4.73, SD = 0.25), safety (Mean = 4.93, SD = 0.12), ergonomic suitability (Mean = 4.70, SD = 0.26), and sit-to-stand support system (Mean = 4.83, SD = 0.17). From actual users, 7 out of 9 participants reported easier sit-to-stand performance, 6 out of 9 reported reduced knee pain, and most felt safer and more confident. Comparisons revealed that the sit-to-stand chair was more suitable for daily use, while the rehabilitation chair was better suited for scheduled exercise and rehabilitation.

Recommendations include improving seat cushion softness, reducing overall chair weight, and enhancing adjustability to accommodate diverse body types. In conclusion, both chair models demonstrated high potential for application in healthcare facilities and household settings, significantly improving safety, daily functional ability, and rehabilitation outcomes for the elderly. Knowledge transfer regarding production, usage, and maintenance was also provided to local health organizations to ensure sustainable use in the community.

Keywords: elderly; knee osteoarthritis; rehabilitation chair; sit-to-stand chair; ergonomics; QFD; safety