Corticospinal and Spinal-Reflex Excitability during Unipedal Stance Following Acute Lateral Ankle Sprain

Area of Science:

• Neuroscience
• Sports Medicine
• Orthopedics

Background:

• Acute lateral ankle sprains (ALAS) can alter neural excitability, potentially leading to sensorimotor dysfunction.
• Understanding both spinal and supraspinal mechanisms is crucial for assessing ALAS-related deficits.

Purpose of the Study:

• To investigate the impact of ALAS on neural excitability during unipedal stance.
• To correlate these neural adaptations with clinical outcomes.

Main Methods:

• Assessed spinal-reflex excitability via Hoffmann reflex (H-reflex) and corticospinal excitability using motor evoked potentials (MEPs).
• Measured unipedal center-of-pressure (CoP) for postural control and evaluated acute symptoms and ankle disability.

Main Results:

• No significant differences in spinal-reflex excitability between ALAS and control groups.
• Significantly higher corticospinal excitability observed in the ALAS group across all stimulus intensities.
• ALAS group showed impaired postural control (increased CoP area and velocity) and a correlation between higher corticospinal excitability and greater ankle disability.

Conclusions:

• ALAS primarily affects neural excitability at the corticospinal level during unipedal stance.
• Corticospinal alterations may contribute to the sensorimotor deficits and disability experienced after ALAS.