Cortical Changes After Upper Limb Immobilization Measured by Electroencephalography (EEG)

Effects of Upper Limb Immobilization on Sensorimotor Cortical Activity and Function Measured by EEG: A Prospective Observational Study

This study aims to investigate how temporary immobilization of the upper limb after injury affects brain activity and functional recovery.

Participants with fractures or soft tissue injuries of the upper limb who require immobilization will be evaluated at three time points: at the beginning of immobilization, after removal of the immobilization, and four weeks later.

Brain activity will be measured using electroencephalography (EEG), a non-invasive and painless technique that records electrical signals from the scalp. Functional outcomes such as pain, mobility, strength, and daily activity performance will also be assessed using validated questionnaires and clinical tests.

The purpose of this study is to better understand how immobilization influences the brain and physical recovery, in order to improve rehabilitation strategies for patients with upper limb injuries.

Participation is voluntary, and all participants will provide written informed consent.

Study Overview

• Status: Active, not recruiting
• Conditions: Muskuloskeletal Diseases; Wrist Injury; Hand and Upper Limb Trauma
• Intervention / Treatment: Other: Orthopedic Immobilization; Other: Standard Rehabilitation

Detailed Description

Upper limb immobilization is commonly required after fractures and soft tissue injuries to promote healing. However, prolonged immobilization can lead to muscle weakness, sensory deficits, and changes in brain activity related to motor control.

Previous research has shown that even short periods of limb disuse can induce neuroplastic changes in the sensorimotor cortex. These changes may contribute to persistent functional limitations after immobilization is removed.

This prospective observational study aims to describe and quantify changes in sensorimotor cortical activity and functional outcomes associated with clinical immobilization of the upper limb.

Adult patients requiring immobilization for upper limb fractures or soft tissue injuries will be recruited. Eligible participants will be evaluated at three time points: baseline (within five days of immobilization), post-immobilization (within 24-48 hours after removal), and follow-up (four weeks after post-immobilization).

Brain activity will be recorded using a portable wireless electroencephalography (EEG) system following the international 10-20 electrode placement system. Resting-state and task-related recordings will be obtained. Spectral power in standard frequency bands and functional connectivity measures will be analyzed.

Clinical and functional outcomes will include patient-reported questionnaires (PRWE, QuickDASH, MHQ, SPADI, TSK-11, PCS), range of motion, grip strength, and joint position sense.

Statistical analyses will focus on longitudinal changes across time points using repeated-measures analysis of variance or mixed-effects models, depending on data distribution. Effect sizes and confidence intervals will be reported.

This study has been approved by the local ethics committee, and all participants will provide written informed consent prior to participation.

The results are expected to contribute to a better understanding of brain plasticity during immobilization and support the development of more effective rehabilitation strategies.

• Study Type: Observational
• Enrollment (Estimated): 30

Contacts and Locations

Study Locations

• Spain
  • Málaga
    • Málaga, Málaga, Spain, 29071
      • UMA

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult patients requiring orthopedic immobilization of the upper limb following fracture or soft tissue injury. Participants are consecutively referred from the traumatology units of hospitals in Málaga and undergo clinical and neurophysiological evaluation under supervision of the research team. The study population represents individuals undergoing routine clinical immobilization and subsequent rehabilitation as part of standard orthopedic management.

Description

Inclusion Criteria:

• Adults aged 18 years or older.
• Radiologically confirmed upper limb fracture (distal radius, proximal humerus, metacarpals, phalanges, or carpal bones) or soft tissue injury (e.g., tendinopathy, triangular fibrocartilage complex injury).
• Requirement of orthopedic immobilization of the wrist/hand extending to the proximal two-thirds of the forearm for a minimum of 2 weeks and a maximum of 8 weeks.
• Ability to understand study procedures and follow instructions.
• Provision of written informed consent.

Exclusion Criteria:

• History of neurological disorders (e.g., stroke, epilepsy, traumatic brain injury).
• Current use of psychoactive or anticonvulsant medication.
• Bilateral upper limb injuries.
• Wrist fractures requiring elbow immobilization.
• Previous upper limb fracture or instability within the last 2 years.
• Cognitive impairment preventing adequate participation.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Upper Limb Immobilization Cohort; Adults with upper limb fracture or soft tissue injury requiring orthopedic immobilization for 2-8 weeks. Participants undergo repeated neurophysiological and clinical assessments at baseline (within 5 days from the start of immobilization), post-immobilization (within 24-48 hours after removal of the immobilization), and 4-week follow-up (4 weeks after splint or cast removal).

Other: Orthopedic Immobilization; Standard orthopedic immobilization of the upper limb (wrist/hand) as part of routine clinical management following fracture or soft tissue injury.; Other: Standard Rehabilitation; Conventional wrist and hand rehabilitation provided according to clinical practice after immobilization removal.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Sensorimotor Cortical Activity Measured by EEG	Changes in sensorimotor cortical activity measured using electroencephalography (EEG), including spectral power in mu (8-13 Hz) and beta (13-30 Hz) frequency bands over central regions (C3, C4 and adjacent electrodes), and functional connectivity between motor and somatosensory areas.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Upper Limb Pain and Disability (PRWE)	Patient-Rated Wrist Evaluation (PRWE) total score (0-100), assessing pain and functional disability of the wrist and hand. Higher scores indicate greater pain and disability.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Upper Limb Functional Status (QuickDASH)	Quick Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH), 11-item self-reported measure of upper limb disability (0-100). Higher scores indicate greater disability.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Hand Function (Michigan Hand Outcomes Questionnaire)	Michigan Hand Outcomes Questionnaire (MHQ) total score assessing hand function, activities of daily living, pain, work performance, aesthetics, and satisfaction. Scores range from 0 to 100 depending on domain.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Shoulder Pain and Disability (SPADI)	Shoulder Pain and Disability Index (SPADI), 13-item questionnaire assessing shoulder pain and disability. Scores range from 0 to 100, with higher scores indicating greater impairment.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Grip Strength	Grip strength measured in kilograms using a Jamar dynamometer under standardized positioning (shoulder adducted, elbow flexed 90°, forearm neutral). Bilateral measurements recorded.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Wrist Range of Motion	Active wrist range of motion (flexion, extension) measured in degrees using a goniometer under standardized positioning.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Joint Position Sense (Proprioception)	Joint Position Sense (JPS) error measured in degrees as the absolute difference between target and reproduced wrist position.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Pain Catastrophizing (PCS)	Pain Catastrophizing Scale (PCS), a 13-item self-reported questionnaire assessing rumination, magnification, and helplessness related to pain. Each item is scored from 0 to 4. Total scores range from 0 to 52, with higher scores indicating greater pain catastrophizing.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.
Change in Kinesiophobia (TSK-11)	Tampa Scale for Kinesiophobia (TSK-11), an 11-item self-reported questionnaire measuring fear of movement and reinjury. Each item is rated on a 4-point Likert scale. Total scores range from 11 to 44, with higher scores indicating greater fear of movement.	Baseline (within 5 days of immobilization), 24-48 hours after immobilization removal, and 4 weeks post-removal.

Collaborators and Investigators

• Sponsor: University of Malaga

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): February 1, 2027

Study Registration Dates

• First Submitted: February 16, 2026
• First Submitted That Met QC Criteria: February 16, 2026
• First Posted (Actual): February 23, 2026

Study Record Updates

• Last Update Posted (Actual): June 3, 2026
• Last Update Submitted That Met QC Criteria: June 2, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Electroencephalography; Functional recovery; Sensorimotor cortex; Limb immobilization
• Additional Relevant MeSH Terms: Wounds and Injuries; Arm Injuries; Wrist Injuries
• Other Study ID Numbers: UMA-EEG-IMM-2026-002; 231-2025-H (Registry Identifier: CEUMA)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No