The purpose of this clinical trial is to find out whether a rehabilitation program based on different dimensions of balance can improve balance, mobility, walking ability, and quality of life in people with acquired brain injury.

The main questions this study aims to answer are:

• Does this rehabilitation program improve balance?
• Does it improve mobility and walking ability?
• Does it reduce the risk of falls?
• Does it improve quality of life?

Researchers will compare a specific balance rehabilitation program with conventional physiotherapy to determine whether the balance program provides additional benefits.

Participants with acquired brain injury who meet the eligibility criteria will be randomly assigned to one of two groups. Both groups will receive treatment for 12 weeks.

Participants will:

• Complete balance and mobility assessments before starting treatment.
• Receive either the balance rehabilitation program or conventional physiotherapy five times per week.
• Complete assessments immediately after treatment and again 6 and 12 weeks later.

The information obtained from this study may help improve rehabilitation programs and daily functioning for people with acquired brain injury.

Acquired brain injury (ABI) is a major cause of disability in adults. It can affect balance, walking, mobility, independence in daily activities, and quality of life. Balance problems are common after ABI and may increase the risk of falls.

This study will evaluate a rehabilitation program based on different dimensions of balance in people with ABI. The program is designed to work on proprioception, biomechanical constraints, limits of stability, anticipatory postural adjustments, reactive postural responses, sensory orientation, and dynamic gait stability.

This is a prospective, longitudinal, randomized controlled trial with assessor blinding. The study will include 68 adults with ABI who are receiving active rehabilitation at the State Reference Centre for Brain Injury Care (CEADAC) in Madrid, Spain. Participants will be randomly assigned to one of two groups.

The experimental group will receive a structured multimodal balance rehabilitation program. The control group will receive conventional physiotherapy according to the usual clinical protocols at CEADAC. Both groups will receive treatment for 12 weeks, with five 60-minute sessions per week.

The main outcome will be balance performance, assessed with the Balance Evaluation Systems Test adapted for Acquired Brain Injury (BESTest_DCA). Secondary outcomes will include mobility, walking speed, fall risk, and quality of life, assessed with the Timed Up and Go Test, the 10-Meter Walk Test, and the CAVIDACE questionnaire (Spanish Quality of Life Questionnaire for People with Acquired Brain Injury).

Assessments will be performed at baseline, after 6 weeks of treatment, after 12 weeks of treatment, and at 6 and 12 weeks after the end of the intervention. Data will be analyzed to compare changes between the experimental and control groups over time.

This study may help determine whether a balance-specific rehabilitation program provides additional benefits compared with conventional physiotherapy in people with acquired brain injury.

Inclusion Criteria:

• Adults aged 18 to 65 years.
• Diagnosis of acquired brain injury (stroke, traumatic brain injury, anoxic brain injury, brain tumor, or encephalitis).
• At least 2 months since the brain injury.
• Mini-Mental State Examination (MMSE) score greater than 24.
• Modified Rankin Scale (mRS) score of 3 or lower.
• Ability to walk independently or with an assistive device.
• Clinical stability and ability to participate in a rehabilitation program.
• Written informed consent signed by the participant.

Exclusion Criteria:

• Severe cognitive impairment (MMSE score of 24 or lower).
• Severe functional dependence (mRS score greater than 3).
• Unstable medical conditions that may interfere with participation.
• Severe musculoskeletal, cardiovascular, or other conditions that prevent safe participation in the intervention.
• Severe communication disorders that prevent understanding of study procedures.
• Participation in another clinical trial that may interfere with the study results.

De-identified individual participant data underlying the results reported in publications will be shared. This includes demographic variables, baseline characteristics, intervention allocation, balance assessment scores (BESTest and secondary outcome measures), and follow-up data collected during the study. All direct identifiers will be removed before data sharing to protect participant confidentiality.

Data and supporting information will become available 12 months after publication of the primary study results and will remain available for 5 years.

De-identified data will be available upon reasonable request from qualified researchers for scientific purposes. Requests must include a research proposal and will be reviewed by the principal investigator. Access will be granted only after approval and in accordance with the study ethical approval, Spanish legislation, and the European General Data Protection Regulation (GDPR).

Outcome assessors will be blinded to group allocation. Due to the nature of the intervention, participants and physiotherapists delivering the treatments cannot be blinded. Outcome assessments will be performed by an independent evaluator who will not have access to treatment allocation information. Statistical analyses will be conducted using anonymized data coded by group.