Virtual Reality Therapy for Wrist and Hand Injury Recovery

Traumatic injuries of the wrist and hand are common causes of disability of the upper limb in adults. They frequently require a period of immobilization in a cast or splint to allow bone and soft tissues to heal. However, prolonged immobilization is associated with muscle atrophy, reduced strength, joint stiffness, proprioceptive deficits and, importantly, rapid neuroplastic changes in the motor cortex and related brain networks. These changes contribute to a maladaptive pattern of "disuse plasticity" that may persist after immobilization and is linked to chronic pain, fear of movement, and incomplete functional recovery.

Recent research shows that brain plasticity can be positively modulated through interventions based on motor representation, such as motor imagery and action observation therapy (AOT). In AOT, patients watch goal-directed movements that are similar to the actions they need to relearn. This activates the mirror neuron system and motor cortical areas even when the limb is not actively moving. Immersive virtual reality (VR) can enhance these effects by providing a first-person, three-dimensional environment that increases attention, motivation, sense of presence, and perceived control.

This study proposes an early neuro-functional intervention that combines AOT with immersive VR (AOT+VR) during and after the immobilization period in patients with traumatic wrist and hand injuries. The trial is designed as a randomized, controlled, parallel-group clinical study. Eligible participants (18-70 years, traumatic wrist/hand injury requiring 2-8 weeks of immobilization) will be randomly assigned to:

a control group, receiving only conventional rehabilitation according to standard clinical practice after immobilization, or an experimental group, receiving the same conventional rehabilitation plus the structured AOT+VR program.

The experimental protocol consists of approximately 12 sessions (±2), 45 minutes each, delivered twice per week over 6 weeks. In each session, participants use a VR headset (Meta Quest 3S) to observe videos of functional, uni- and bimanual upper-limb tasks from a first-person perspective (for example, reaching, grasping objects, using cutlery, writing, or daily-life activities). After each observation period, the headset is removed and the participant executes the observed movements with the affected limb as tolerated, repeating this observation-execution cycle several times per session. Exercises progress gradually from simple movements without gravity to complex functional tasks, allowing individual adaptation. Sessions are stopped immediately if adverse effects such as dizziness, nausea, or disorientation appear.

Outcome assessments are performed at three time points: baseline (within the first 5 days after starting immobilization), post-immobilization (24-48 hours after cast or splint removal), and follow-up (6 weeks after post-immobilization).

The primary outcome is sensorimotor cortical activity associated with action observation and execution, assessed using electroencephalography (EEG). Neurophysiological markers include event-related potentials (ERPs) time-locked to action observation and execution tasks, and event-related desyinchronization/synchronization (ERD/ERS) within the mu (8-13 hz) and beta (13-30 hz) frecuency bands over sensorimotor cortical regions. Secondary outcomes include pain and perceived disability (PRWE, QuickDASH, MHQ, SPADI), psychological factors (Tampa Scale of Kinesiophobia-11, Pain Catastrophizing Scale), physical measures of wrist range of motion, grip strength, proprioception, and feasibility and safety indicators (recruitment and adherence rates, adverse events related to VR or TMS, completeness of data and participant satisfaction).

The central hypothesis is that early AOT+VR will attenuate the reduction in sensorimotor cortical activity associated with immobilization, support more adaptive brain reorganization, and lead to better clinical outcomes than conventional care alone. By integrating neurophysiological, functional, and psychological measures, the study aims to clarify the mechanisms of action of AOT+VR and to determine whether this low-risk, technology-supported intervention is feasible and acceptable in real clinical settings for early rehabilitation after traumatic wrist and hand injuries.

Inclusion criteria

• Age 18-70 years old.
• Diagnosis of traumatic wrist and/or hand injury within 5 days of injury onset.
• Traumatic injury types include: distal radius fractures, scaphoid fractures, metacarpal fractures, phalangeal fractures, other carpal bone fractures, tendinous injuries, or ligamentous injuries.
• Require immobilization with cast or splint for 2-8 weeks.
• Ability to provide written informed consent.
• Ability to understand and follow study instructions.
• Sufficient mobility and residual manual capacity to participate in virtual reality sessions and physical assessments.

Exclusion criteria

• History of neurological disease affecting motor control (stroke, Parkinson's disease, multiple sclerosis).
• Severe psychiatric disorders (psychosis, severe depression requiring hospitalization).
• Current involvement in other rehabilitation protocols or clinical trials.
• Contraindications for using virtual reality.