JMIR Publications

ABSTRACT

Background:

Personalised prosthetic socket design depends upon highly skilled prosthetists. They aim to balance functional human-prosthesis coupling with safe, comfortable load transmission from the prosthesis to the skeleton, through vulnerable skin and soft tissues. Both traditional plaster and Computer Aided Design and Manufacturing (CAD/CAM) methods are iterative, and sharing knowledge is difficult. Evidence-Generated (EG) Sockets derived from past Computer Aided Socket Design (CASD) records could provide a personalised starting point for limb fitting, potentially reducing time spent on basic design and enabling prosthetists to focus on more highly-skilled customisation.

Objective:

To assess the comfort of Evidence-Generated sockets, generated from past computer aided socket design records.

Methods:

A crossover trial compared EG sockets, derived from 163 previous transtibial devices, to conventional clinician-led CAD/CAM sockets. Non-inferiority was assessed for the Socket Comfort Score (SCS) outcome measure, and semi-structured interviews provided in-depth user analysis. The setting was three United Kingdom National Health Service clinics, with seventeen participants with nineteen transtibial amputations.

Results:

Evidence-Generated sockets had no statistically-significant difference in comfort compared to clinician-led Control sockets (median SCS 8.6 for EG sockets and 8.8 for CAD/CAM controls; p=0.38, effect size=0.08), but a lower variability in socket comfort score across the group (95% confidence intervals 8.0-9.0 and 7.5-9.5 for EG and CAD/CAM devices, respectively). Analysis of interviews revealed themes around fitting session experiences, similarities and differences between the Evidence-Generated and CAD/CAM control sockets, and residual limb factors impacting perceptions of socket comfort. These provided insights into the participants’ experience of the study and the value of expert prosthetist input in socket design.

Conclusions:

Evidence-Generated sockets demonstrated noninferiority to conventional clinical CASD practice in terms of socket comfort. Both quantitative and qualitative results indicated how clinician input remains essential and is valued by prosthesis users. Work is underway to incorporate the Evidence-Generated Sockets into computer aided design software such that they can act as a digital starting point for modification by expert clinicians at fitting, potentially reducing time spent on basic design, enabling prosthetists to focus on more highly-skilled customisation and co-design with their patients. Clinical Trial: clinicaltrials.gov NCT06597266.