Astronauts that are part of long missions in space suffer from atrophy of the muscles supporting the spine. Most of the time the back of the astronauts does not return to normal, leaving them with pain even several weeks after they are back on Earth.
The study shows evidence of a common problem among astronauts: back pain. According to Drs. Alan R. Hargens and Jeffrey C. Lotz, the results of the survey are a helpful information to take into consideration for future space trips to Mars and the manned mission planned for 2030. The research provides new insights into the elevated rates of spinal problems, including spinal disc disease associated with prolonged spaceflight, said Dr. Douglas G. Chang of University of California, San Diego, and colleagues.
The study includes the evaluation of six astronauts that went to the International Space Station, who spent between four to seven months in the space facility. All of them underwent magnetic resonance imaging (MRI) scans of the spine before leaving the planet and immediately after their return to Earth. Two months later after they were home, they underwent, one more time, MRI’s to determine any problems on their backs.
The research’s goal was to identify what causes the common back pains in astronauts as well as the spine’s response when the crew came back to Earth’s gravity. Back pain is one of the most chronic health issues suffered by most of the people that go to space for prolonged periods.
More than half of the crew members have reported back pains and are often at high risk of suffering spinal disc herniation after returning from their missions.
Being in space also increases body height, which is related to spinal “unloading” and other factors related to the lack of gravity. Some astronauts have grown about two inches after coming back from space.
To understand the factors causing lumbar spine strength and low back pains reported in long-duration flights, researchers used the image “tresh-holding” technique to evaluate lean muscle separated from non-lean muscle components.
Astronauts need to do more exercises to prevent back pain: Yoga is a great alternative
The findings showed that paraspinal muscle atrophy could be avoided with core-strengthening exercises, such as those suggested for people with back pains on Earth. Astronauts already train when they are out in space, and adding back-centered exercises could reduce the spinal effects of spaceflight.
Around 70 percent of astronauts suffer from discomfort during their first few days in space. About half experience severe spine pain and slipped discs. Sometimes the pain lasts all the mission. Dr. Chang suggested yoga in the research to treat spinal stiffness and reduced mobility.
These illnesses make it difficult for astronauts to perform at their 100 percent. If humanity plans to conquer Mars, back problems caused by extended missions into space must be solved.
“Whether new exercise countermeasures can prevent in-flight paraspinal muscle atrophy, improve spinal pain and function, shorten recovery time, and how such exercise might be performed in a microgravity environment with available exercise equipment need further study,” stated Dr. Chang and her colleagues.
The magnetic resonance images revealed how astronauts’ spine changes through a long trip to space
The MRI scans indicated severe atrophy of the paraspinal lean muscle mass during the astronauts’ four to seven months in the ISS. Paraspinal lean muscle mass is essential to spinal support and movement, and without it, the crew will suffer back pains.
The images show that the lean muscle or “functional,” cross-sectional area of the lumbar paraspinal muscles were reduced by an average of 19 percent from preflight to immediate postflight scans.
Time was not enough to heal the damage caused in space. Even after two months of being back on Earth, crew members’ MRIs indicated that only about two-thirds of the reduction had recovered.
MRIs showed that the ratio of lean muscle decreased from 86 percent —the percentage found in the preflights studies— to 72 percent immediately postflight. The tests performed on the astronauts after they had been on Earth for two months indicated that the ratio recovered to 81 percent, a positive result although it does not reach the original ratio.
Regarding changes in the height of the intervertebral spinal discs, the study indicated that there were no consistent changes. According to Dr. Chang and co-authors, the measurements taken into consideration ran counter to the previous hypothesis about the effects of microgravity on disc swelling.
More investigation is needed to determine what causes the growth of astronauts in space and clarify the effects of microgravity on disc height. The increased risk of herniated disc disease also requires more studies. The study was published Tuesday in the journal Spine.