Detecting altered postural control after cerebral concussion in athletes with normal postural stability

Area of Science:

• Sports Medicine
• Neurology
• Biophysics

Background:

• Concussion can impact postural control, a critical function for athletes.
• Traditional assessments may not detect subtle changes in athletes with outwardly normal stability post-concussion.

Purpose of the Study:

• To evaluate if approximate entropy (ApEn), a non-linear dynamics measure, can identify alterations in postural control during quiet standing in athletes after a cerebral concussion.
• To assess ApEn's utility in detecting changes despite normal postural stability post-injury.

Main Methods:

• Retrospective analysis of centre of pressure (COP) data from NCAA Division I athletes before and within 48 hours after concussion.
• Calculation of ApEn values for anterior-posterior (AP) and medial-lateral (ML) COP time series during the Sensory Organization Test (SOT).
• Comparison of ApEn values between concussed athletes and healthy non-athletes.

Main Results:

• Athletes showed more regular COP oscillations (lower ApEn) after concussion compared to healthy controls, despite normal postural stability.
• Significant declines in ApEn for AP time series were observed in early SOT conditions.
• ApEn values decreased in ML time series across all sensory conditions post-concussion.

Conclusions:

• Subtle changes in postural control exist in athletes with normal postural stability after concussion.
• ApEn analysis of COP data may reveal clinically significant findings not detected by standard tests.
• ApEn offers a potential supplementary tool for concussion assessment in athletes.