Preliminary effectiveness of 3D-printed orthoses in chronic hand conditions: study protocol for a non-randomised interventional feasibility study

INTRODUCTION: Hand orthoses are often provided to improve performance of activities of daily life (ADL). Yet, the manufacturing process of conventional custom-fabricated hand orthoses is a time-consuming and labour-intensive process. Even though three-dimensional (3D) printing of orthoses is a rapidly growing area that can facilitate the manufacturing process of hand orthoses, evidence on the effectiveness, costs and production time of 3D-printed orthoses in chronic hand conditions is scarce. This study aims to assess (1) the preliminary effectiveness of 3D-printed orthoses compared with conventionally custom-fabricated orthoses in persons with chronic hand conditions, (2) production time and costs of both orthoses and (3) experiences of the participants and orthotists with the manufacturing process of the 3D-printed orthosis. METHODS AND ANALYSIS: In this prospective non-randomised interventional feasibility study, 20 adults with various chronic hand conditions using a conventional thumb, wrist or wrist-thumb orthosis will be provided with a 3D-printed corresponding type of orthosis. Assessments will be done 2 weeks prior to the intervention and at baseline for the conventional orthosis, and at 1 month and 4 months follow-up for the 3D-printed orthosis. The primary outcome is change from baseline in ADL performance (custom short form Dutch-Flemish Patient-Reported Outcomes Measurement Information System-Upper Extremity; ADL domain Michigan Hand Outcomes Questionnaire Dutch language version (MHQ-DLV)) at 4 months follow-up. Secondary outcomes include general hand function (MHQ-DLV), satisfaction with the orthosis (Dutch Client Satisfaction with Device; Dutch version of the Quebec User Evaluation of Satisfaction with Assistive Technology), usability (in-house questionnaire) and quality of life (EuroQoL 5-Dimension 5-Level). Costs and production time of the conventional and 3D-printed orthoses will be prospectively recorded. Experiences regarding the manufacturing process will be obtained from participants and orthotists (in-house questionnaire). ETHICS AND DISSEMINATION: The Medical Ethics Committee of the Amsterdam UMC, Academic Medical Centre, has waived the requirement for ethical review of this study. Results will be disseminated through peer-reviewed journals, scientific conferences, and media aimed at a broad audience including patients. TRIAL REGISTRATION NUMBER: NCT05320211.