Diagnostic accuracy of dynamic posturography testing after short-duration spaceflight

Area of Science:

• Aerospace Medicine
• Neuroscience
• Human Physiology

Background:

• Astronauts experience sensorimotor function disruptions post-spaceflight.
• Computerized dynamic posturography (CDP) is used to assess recovery.
• The diagnostic accuracy of CDP for return-to-duty decisions remains unestablished.

Purpose of the Study:

• To evaluate the diagnostic accuracy of CDP for post-spaceflight sensorimotor deficits.
• To identify the most effective CDP test components for assessing astronaut recovery.
• To inform return-to-duty decision-making for astronauts.

Main Methods:

• 11 astronauts and 11 controls underwent CDP before and after spaceflight.
• CDP testing involved eyes closed, standing on a force plate with perturbed somatosensory and vestibular input.
• Equilibrium (EQ) scores were analyzed using receiver operator characteristic (ROC) curves.

Main Results:

• The most accurate test involved dynamic head movements on an unstable force plate (94.9% sensitivity, 96.6% specificity, ROC AUC = 0.991).
• The standard clinical Romberg test showed significantly lower diagnostic accuracy (ROC AUC = 0.718).

Conclusions:

• The dynamic head movement CDP test demonstrates high diagnostic accuracy for post-spaceflight sensorimotor deficits.
• This CDP test paradigm should be considered for astronaut return-to-duty decisions.
• Objective CDP measures can enhance the safety and efficacy of astronaut return-to-duty protocols.