The use of computer-aided design and manufacture for foot orthoses: a cross-sectional study of orthotic services in the UK

Abstract

Objective: This study aimed to identify how computer aided design and manufacture (CAD/CAM) technologies are currently being used for insole production by UK Orthotic services in the National Health Service (NHS), including any variation in the specific processes and identify barriers to implementation.

Design: A cross-sectional study was undertaken using freedom of information requests sent to all 214 NHS Trusts and Health Boards (HB) across the UK. The request comprised 22 questions relating to CAD/CAM for insole production by UK NHS Orthotic services during the 2021/22 financial year.
Outcome measures: Analysis was undertaken and presented in terms of response rate to individual questions. Where free text responses were provided, thematic analysis was conducted.

Results: Responses were received from 186 (86.9%) Trusts/HBs, those who did not have an orthotic service were excluded, and 131 responses were included in the final analysis. 70.5% (91/129) of Trusts/HBs used CAD/CAM to manufacture bespoke insoles. The most common workflow associated with CAD/CAM insole production was foot-shape capture with a foam-box impression cast (86.8% (79/91)); casts transported to another site (90.8% (79/87)); foam-boxes scanned into a CAD/CAM system (81.6% (71/87)); insoles designed by a technician (73.6% (67/91)) and insole produced with reduction milling (59.1% (SD 37.92)). The greatest barriers to the use of CAD/CAM were those of equipment costs and staff experience and training.

Conclusions: UK orthotic services have widely adopted CAD/CAM insole production, but fully-digital workflow is uncommon. Hybrid-digital workflow involves physical casts and their transportation, generating waste and impacting sustainability. Further research is required to understand how hybrid-digital and fully-digital workflow affect patient treatment outcomes, costs and sustainability. Barriers to CAD/CAM including costs and staff training which should be considered alongside the growing body of research around CAD/CAM technologies.