Space Station Crew To Study Why Astronauts Get Taller In Space
January 2, 2013

Space Station Crew To Study Why Astronauts Get Taller In Space

Lee Rannals for — Your Universe Online

Researchers are looking into why astronauts are able to grow taller while spending time aboard the International Space Station (ISS).

Astronauts who are living aboard the orbiting laboratory have been known to grow 3 percent taller while living in microgravity. However, they return to their normal height when back on Earth. NASA has now commissioned a Spinal Ultrasound investigation to better understand this change.

"This is the very first time that spinal ultrasound will be used to evaluate the changes in the spine," Scott A. Dulchavsky, M.D., Ph.D., principal investigator for the station study, said in a statement. "Spinal ultrasound is more challenging to perform than many of the previous ultrasound examinations done in space."

The difficulty with imaging the spine is simply due to human anatomy, NASA said. Using the Ultrasound 2 machine aboard the space station gives astronauts an advanced tool to view the inner workings of their bodies.

"Today there is a new ultrasound device on the station that allows more precise musculoskeletal imaging required for assessment of the complex anatomy and the spine," Dulchavsky said. "The crew will be able to perform these complex evaluations in the next year due to a newly developed Just-In-Time training guide for spinal ultrasound, combined with refinements in crew training and remote guidance procedures."

The research could help develop exercises for better crew health and guiding improved rehabilitation techniques when astronauts return to Earth. Helping to understand how changes to the spine occur in real-time response to life in space will help crews prepare for future long-duration missions.

Dulchavsky said that another benefit of the research is that it could also reduce costs and provide a safer imaging option for patients here on Earth.

"Ultrasound also allows us to evaluate physiology in motion, such as the movement of muscles, blood in vessels, and function in other systems in the body," he said in the statement. "Physiologic parameters derived from ultrasound and Doppler give instantaneous observations about the body non-invasively without radiation."

During the investigation, six crew members will be serving as test subjects for these spinal ultrasound scans. The data sessions are scheduled to take place on orbit starting in January 2013.

Astronauts will scan the spinal area of fellow crew members at 30, 90 and 150 days into flight. Researchers will be watching in real time from the ground through streaming video downlinks. Ultrasound images will focus on the cervical and lumbar areas of the spine and surrounding tissues.

Test subjects will also undergo pre- and post-flight ultrasound and MRI scans on Earth to provide more data.

"This technique in spinal ultrasound may someday serve as a clinical data source where standard MRI imaging is not available, even if this seems ambitious," Dulchavsky said. "The vast majority of the global population has no access to an MRI. The in-flight tools such as the interactive Spinal Ultrasound guide can also be used to train other complex procedures, albeit medical or otherwise."

Researchers hope the study sheds a little more light as to why astronauts get taller in space, but also adds to more knowledge of the spine.