Visual information modulates brain network characteristics during static balance following ACL reconstruction - A...

Area of Science:

• Neuroscience
• Biomechanics
• Orthopedics

Background:

• Long-term balance impairments are common after anterior cruciate ligament (ACL) injury.
• These impairments may stem from an overreliance on visual input and associated cortical processing.
• Understanding neural adaptations in postural control post-ACL reconstruction (ACLR) is crucial.

Purpose of the Study:

• To investigate functional brain network characteristics for postural control in individuals post-ACLR compared to controls.
• To examine how these networks differ with and without visual input.
• To explore the relationship between brain network function and balance performance post-ACLR.

Main Methods:

• Single-leg balance tasks were performed by 27 individuals post-ACLR and 24 controls under eyes-open and eyes-closed conditions.
• Mobile electroencephalography (EEG) was used to derive graph-theoretical measures of functional brain network segregation (clustering coefficient, CC) and integration (path length, PL).
• Center of pressure (CoP) sway, center of mass (CoM) kinematics, and knee kinematics were analyzed.

Main Results:

• The ACLR group showed significantly greater cortical network segregation (higher CC) in the alpha-1 band (8-10 Hz) during eyes-open conditions (p=0.025).
• No significant differences in sway characteristics were observed between groups.
• The ACLR leg exhibited greater knee flexion during the balance task compared to the contralateral leg (p=0.036).

Conclusions:

• Individuals post-ACLR demonstrate more efficient functional brain connectivity during eyes-open balance tasks.
• These neural adaptations are accompanied by kinematic adjustments in the injured limb.
• Findings suggest significant neural adaptations in postural control mechanisms following ACLR, particularly when relying on visual information.