Acceptability of Paediatric Wrist Orthoses Through Co-design

Background Pediatric upper limb orthoses are essential rehabilitative and assistive devices for children with musculoskeletal and neurological conditions, particularly those with neuromotor disorders resulting from acquired or congenital brain injury such as cerebral palsy. Despite technological advances in orthotic design, a fundamental challenge persists: most pediatric orthoses are adaptations of devices originally conceived for adults, often overlooking the specific physical characteristics and aesthetic needs of children. This approach can compromise device acceptability and, consequently, therapeutic efficacy.

Growing evidence highlights the critical role of aesthetic and psychosocial factors in assistive technology adoption. Children may refuse to use orthoses perceived as bulky, unattractive, or stigmatizing among peers. Social context and peer judgment significantly influence a child's perception and use of the device, potentially affecting self-image and psychosocial wellbeing.

Simultaneously, the literature emphasizes the benefits of co-design approaches and User-Centred Design (UCD) philosophy in assistive technology development. Active involvement of end users in the design process allows integration of their experiences, preferences, and emotions, leading to more accepted devices. This approach recognizes disability as an individual experience and aims to create a positive affective bond between the product and the user. Despite these recognized benefits, significant gaps remain in the literature specifically regarding pediatric upper limb orthoses: while co-design has been successfully applied in prosthetics for adults, analogous studies focused on the pediatric population are lacking.

Study Design This is a single-center, prospective, no-profit, pre-post interventional pilot study conducted at the IRCCS Eugenio Medea - "La Nostra Famiglia" Association, Bosisio Parini (LC), Italy.

All activities directly involving patients and caregivers are conducted at the Bosisio Parini site.

Intervention Details Phase 1 - Baseline Assessment (First Appointment)

Patients and their caregiver/tutor are separately administered two validated questionnaires assessing acceptability and satisfaction of the conventional orthosis currently in use:

* The TAM-3 (Technological Acceptance Measure), adapted to the pediatric context
* The QUEST 2.1 (Quebec User Evaluation of Satisfaction Adapted to Children) assesses user satisfaction with the orthosis Motor abilities are assessed by a therapist using standardized clinical scales: MACS (Manual Ability Classification System), MAS (Modified Ashworth Scale), and VAS (Visual Analog Scale) for pain.

A quantitative functional assessment of the upper limb is performed using a certified optoelectronic motion analysis system (BTS Bioengineering Smart DX). Participants perform standardized functional movements - including Hand-to-Mouth and Hit-to-Target (reach) - while wearing the conventional orthosis. A multivariate kinematic protocol developed and validated at IRCCS E. Medea is used to measure joint movements at the wrist, elbow, shoulder, and trunk.

At the end of the first appointment, participants receive a take-home activity kit to complete before the second appointment. This consists of two illustrated boards - one representing a school day, one a holiday - where children reconstruct their daily routine using stickers depicting both activities and emotions related to orthosis use, supplemented by brief written comments. Families photograph and send the completed boards to the researcher prior to the second appointment for preliminary analysis.

Phase 2 - Co-Design Sessions (Second and Third Appointments) Two structured co-design workshops are held on separate days at the Bosisio Parini site, each lasting approximately 1.5 hours, conducted in small groups of up to 7 children with their respective caregivers. A researcher acts as facilitator. Caregivers are present for communicative support only; clear rules ensure that parental involvement does not interfere with children's free expression.

First Workshop - Exploration of Latent Needs and Deep Meanings: Participants engage in play-based expressive activities using creative and non-verbal tools (LEGO blocks, persona cards, crafting materials, colored paper, collage, pencils) to surface lived experiences, aesthetic perceptions, and symbolic values related to their orthosis. Activities may include naming three things they love and three they dislike about their orthosis, or representing abstract concepts related to identity, comfort, visibility, or stigma. Insights gathered inform the design of the second workshop.

Second Workshop - Creative Personalization of the Orthosis: Participants design their "dream orthosis" using drawings, collage, decorative materials, colors, accessories, and 3D-printed orthosis prototypes. They may apply materials, add textures, symbolic elements, or representative accessories to give concrete form to their personalization wishes. The goal is to collect personalized visual inputs to guide the subsequent design and prototyping phase.

At the end of the second workshop, upper limb anatomy acquisition is performed using anthropometric measurements, 3D scanning, and if necessary, plaster casting. All methods aim to produce a digital model of the limb for the subsequent design phase. This step may be supported by technicians from Barbieri S.p.A. - Progettiamo Autonomia.

Orthosis Production The co-designed orthosis is produced at the Bosisio Parini site by the researcher. Following this, Barbieri S.p.A. orthopedic technicians finalize the device and issue the manufacturer's declaration of conformity pursuant to MDR 745/2017.

No costs are borne by the patient or the National Health Service; all costs related to orthosis production are covered by the Promoter.

Phase 3 - Post-Intervention Assessment (Fourth Appointment) The co-designed orthosis is delivered to the patient, who is asked to wear it for at least two hours at the Bosisio Parini site. A therapist then performs a functional assessment identical to that conducted at the first appointment, including VAS pain evaluation. The same TAM-3 and QUEST 2.1 questionnaires are re-administered to both patient and caregiver in separate settings to assess acceptability and satisfaction with the co-designed orthosis.

Additionally, a semi-structured interview with open-ended questions is conducted individually with both the child and the caregiver to explore four domains: (1) experience of the co-design process (enjoyment and engagement); (2) perception of the outcome (aesthetic, functional, and emotional satisfaction); (3) emotional experience during the process and orthosis use; (4) suggestions for future improvements. The interview follows a pre-established guide while allowing for free exploration, and is administered separately to child and caregiver to ensure independent expression.

Statistical Analysis Statistical analyses are conducted using IBM SPSS Statistics. Descriptive statistics are used throughout. Normality of continuous variables is assessed via the Shapiro-Wilk test; normally distributed variables are reported as mean ± standard deviation, non-normal variables as median and interquartile range. Categorical variables are described using absolute frequencies and percentages. TAM-3 and QUEST 2.1 scores for the conventional and co-designed orthoses are compared using descriptive effect estimates with 95% confidence intervals. Correlations between variables are explored descriptively or via Spearman non-parametric coefficients. No subgroup analyses are planned given the limited sample size.

• Orthosis acceptability (Device): Participants will receive a personalized wrist-hand orthosis developed through a co-design process. During two structured workshops, children and caregivers express aesthetic preferences and personalization needs using creative tools (drawings, collage, 3D-printed prototypes). Upper limb anatomy is acquired via 3D scanning and/or anthropometric measurements. The orthosis is then digitally designed, 3D-printed with biocompatible materials using a multicolor FDM printer, finished manually, and certified as a custom medical device per MDR 745/2017. Participants evaluate the co-designed orthosis in terms of acceptability (TAM-3), satisfaction (QUEST 2.1), and upper limb functional performance (optoelectronic motion analysis), comparing outcomes with their conventional orthosis assessed at baseline.

Primary outcomes

• Change in wrist-hand orthosis acceptability as measured by the Technological Acceptance Measure (TAM-3) score between first and last study visit [Baseline and up to 12 months]: Orthosis acceptability is measured using the TAM-3, adapted for the pediatric population, evaluating 9 constructs across 27 items: perceived usefulness, perceived ease of use, self-efficacy, perception of external control, playfulness, anxiety, enjoyment, output quality, and behavioural intention. Each construct is scored as the mean of its items on a 5-point Likert scale (1 = strongly disagree to 5 = strongly agree); higher scores indicate greater acceptability, except for the anxiety subscale where lower scores indicate better outcome. The questionnaire is administered separately to the child and caregiver at baseline (conventional orthosis) and at the final visit (co-designed orthosis). Change from baseline is calculated as the difference between final and baseline scores for each subscale.

Secondary outcomes

• Change in upper limb functional performance as measured by optoelectronic motion analysis between first and last study visit [Baseline and up to 12 months]: Upper limb kinematics are assessed using a certified optoelectronic motion analysis system (BTS Bioengineering Smart DX). Participants perform standardized functional movements (Hand-to-Mouth and Hit-to-Target). Active Range of Motion (ROM) is measured at wrist, elbow, shoulder, and trunk. Qualitative observations of motor performance during functional tasks are also recorded. Assessment is performed with both the conventional and the co-designed orthosis.
• Patient and caregiver experience of the co-design process as assessed by semi-structured interview at final visit [Up to 12 months]: A semi-structured interview with open-ended questions is conducted individually with the child and caregiver at the final visit. It explores four domains: (1) enjoyment and engagement in co-design activities; (2) aesthetic, functional, and emotional satisfaction with the final orthosis; (3) positive or negative emotions associated with the process and orthosis use; (4) suggestions for future improvements. Responses are qualitatively coded and analyzed descriptively.

Sex: All, ages: 6 Years to 14 Years

Inclusion Criteria:

* Age between 6 and 14 years
* Current user of a wrist-hand orthosis for rehabilitative and/or assistive purposes
* Diagnosis of neuromotor disorder following acquired or congenital brain injury (e.g., cerebral palsy)
* Adequate verbal and communicative abilities to participate in interviews and co-design activities
* Currently followed at IRCCS Eugenio Medea, Bosisio Parini (LC)
* Written informed consent provided by parent or legal guardian

Exclusion Criteria:

* Age below 6 years or above 14 years
* Absence of adequate verbal and communicative abilities to participate in interviews and co-design activities (e.g., non-functional or severely limited language)
* Skin allergies
* Behavioural or psychiatric disorders (e.g., emotional problems, anxiety, panic attacks)

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