Sex and gender assessment in upper-limb prosthetic design research

Baldock, Michael; Pickard, Nicolaas; Chadwell, Alix; Kenney, Laurence; Curtin, Sam; Harthikote Nagaraja, Vikranth

Abstract

Background: Though often neglected, sex and gender considerations are critical to product design as they generate product innovation, influence study design, and improve sex and gender equality. In upper-limb prosthetics, research has highlighted multiple design priorities based on the issues faced by users. Two key priorities are the weight and size of prosthetic devices, which cause fatigue, particularly for women. This can lead to prosthesis abandonment, where levels of around 24.5% have been reported5.

Aim: To conduct a scoping review of recently published upper-limb prosthesis designs to investigate whether they are becoming more inclusive towards women.

Method: A systematic search based on PRISMA-ScR guidelines was conducted across six databases (30/08/2024) using search terms and synonyms for prostheses, design, and participants with all upper-limb amputation levels. The studies published since 2016 were then screened by title and abstract to find articles which focused on the design and development of an upper-limb prosthesis and included participants with amputation(s). The final articles were (i) analysed using the SAGER guidelines6; (ii) assessed against the Technology Readiness Levels scale; and (iii) grouped into levels of amputation, device type, design priority aim, and components to assess for sub-group trends.

Results: After de-duplication, 565 articles were screened, leading to 43 articles being taken forward. These included 18 case studies, three case studies with additional able-bodied participants, and 22 multiple participant studies. In the studies with multiple participants, the median number of participants was five, and the total female participant percentage was 15.8%, which is close to the predicted population sex distribution7; however, the median female participant percentage was only 10.3%, suggesting more effort is needed to ensure the population is represented in every study. Notably, across all studies, no results were disaggregated by sex or gender. The detail in reporting of prosthesis size and weight is lacking, with 45% of studies (N=9/20) reporting the component/prosthesis size and only 35% (N=7) providing context or justification. Similarly, 65% (N=13/20) reported the component/prosthesis mass, with 40% (N=8) providing context or justification for the mass.

Discussion: The results were limited to studies with participants who had amputations, which targets studies at the later stages of product development and, therefore, does not provide a full picture of all development stages. The product size justification varied throughout the articles; two referred to the equivalent percentiles of anthropomorphic measurements, with others referencing medium male, average adult, human hand, or one alternate industry device. Weight justification mainly used industry device comparisons, ranging from one to four devices. Two papers disaggregated results by participant. In both cases, different results were seen by the male and female participants; however, the sex variable was never discussed in each article despite the need expressed in the past8.

Conclusion: Despite the median percentage of female participants being close to the predicted population distribution, sex-disaggregated results are uncommon in upper-limb prosthetic research. Even though participant numbers are low in prosthetics, if more articles discussed sex/gender as a variable in their studies, additional findings could inform more inclusive prosthetic designs.

• Presentation Conference Type: Presentation / Talk
• Conference Name: TIPS 2025
• Start Date: Mar 19, 2025
• End Date: Mar 21, 2025
• Acceptance Date: Feb 5, 2025
• Deposit Date: Apr 7, 2025
• Peer Reviewed: Peer Reviewed