The goal of this clinical trial is to evaluate the feasibility and user satisfaction of a non-immersive VR rehabilitation system, i.e. Rehametrics, for gait and balance training in children with CP in children between 4 to 10 years old. Secondary objectives include assessing the system's impact on functional mobility, gross motor function, balance, active participation, and user experience.

Primary hypothesis: rehabilitation intervention with Rehametrics is feasible and well accepted in a clinical setting for children with CP aged 4 to 10 years.

Participants will train exercises related to balance and gait using Rehametrics platform

Background Cerebral palsy (CP) is the most common motor disability in childhood, affecting movement, muscle tone, and posture as a result of a non-progressive lesion in the developing brain. Children with CP frequently present with alterations in gait and postural control that significantly impact their daily functioning and quality of life. Although conventional physical therapy remains the cornerstone of rehabilitation, adherence and motivation are persistent challenges, particularly in pediatric populations. Non-immersive virtual reality (VR) systems, such as Rehametrics, which use standard screens and motion-capture sensors rather than head-mounted displays, offer an interactive, game-based rehabilitation environment that may enhance motivation, promote repetitive motor practice, and provide objective performance metrics to clinicians.

Objective The primary aim of this study is to evaluate the feasibility and user satisfaction of a non-immersive VR rehabilitation system, i.e. Rehametrics, for gait and balance training in children with CP. Secondary objectives include assessing the system's impact on functional mobility, gross motor function, balance, active participation, and user experience.

Methods This is a pre-post single group pilot exploratory study. Ten children aged 4 to 10 years with a diagnosis of CP, confirmed by a pediatric neurologist, will be recruited from Centro Médico Pedro P. Diaz, Arequipa, Peru. Each participant will serve as their own control. The intervention consists of 9 sessions with Rehametrics, a non-immersive VR rehabilitation system designed to train gait and balance through interactive virtual scenarios. Outcome measures include: number of sessions completed, the User Satisfaction Evaluation Questionnaire (USEQ), the Timed Up and Go test (TUG), the Gross Motor Function Measure (GMFM-88), the Pediatric Balance Scale (PBS), the Pittsburgh Rehabilitation Participation Scale (PRPS), and the User Experience Questionnaire (UEQ). Pre- and post-intervention assessments will be conducted by a trained physical therapist blinded to session performance data. Statistical analysis will use paired Student's t-test for normally distributed continuous variables and non-parametric tests (Wilcoxon signed-rank) for ordinal data.

Results Recruitment has not yet commenced. Results from this pilot study are expected to provide preliminary estimates of effect size and feasibility parameters to inform the design of a larger controlled trial.

Conclusions This protocol describes a novel application of Rehametrics, as a rehabilitation tool for children with CP. Findings will contribute evidence on the feasibility, satisfaction and preliminary clinical outcomes of game-based VR training targeting gait and balance in a pediatric rehabilitation setting in a middle income country context.

Inclusion Criteria:

• Age between 4 and 10 years (inclusive) at the time of enrollment.
• Confirmed clinical diagnosis of cerebral palsy documented in the medical record by a pediatric neurologist.
• Gross Motor Function Classification System (GMFCS) level I, II, or III
• Ability to stand independently or with minimal assistance for at least 30 seconds.
• Capacity to interact with a screen-based virtual environment (sufficient visual and cognitive ability to follow game instructions with therapist support).
• Written informed consent provided by parent or legal guardian.
• Availability to attend all scheduled sessions at the clinical site.

Exclusion Criteria:

• Severe or uncontrolled epilepsy that contraindicates interaction with visual stimuli (photosensitive epilepsy).
• Severe cognitive or behavioral impairment precluding participation in game-based VR interaction.
• Presence of acute musculoskeletal injuries or recent surgical interventions (within the preceding 3 months) affecting lower limb function.
• Participation in another rehabilitation research study during the study period.
• Visual impairment not correctable with glasses or lenses.

Participant data will be stored using pseudonymized codes rather than names, preventing identification by persons outside the research team. No information that permits the identification of individual participants will be disclosed in any publication or presentation. All documents containing participant information will be stored in a locked cabinet in a restricted-access area. Digital data will be stored on password-protected systems accessible only to authorized study personnel. Personal identifiers and study codes will be stored in separate, locked locations.