NASA Finds 371 Days in Microgravity Shrinks Spinal Muscles, Raises Disc Injury Risk 4.3-Fold
Updated
Updated · spacedaily.com · Jul 25
NASA Finds 371 Days in Microgravity Shrinks Spinal Muscles, Raises Disc Injury Risk 4.3-Fold
1 articles · Updated · spacedaily.com · Jul 25
Summary
MRI evidence cited by NASA shows long ISS missions leave Intervertebral discs largely unchanged; the main damage is atrophy in spinal stabilizing muscles that makes re-entry to gravity painful and risky.
Paraspinal muscle functional area fell to 72% from 86% by landing, and astronauts recovered only 68% of that loss after six weeks, leaving the spine under-supported when Earth loading resumes.
A separate NASA-linked study found the lumbar spine loses about 11% of its natural curve in microgravity, increasing stress on lower-back discs during the first weeks and months after return.
That helps explain why astronauts face herniated disc rates about 4.3 times higher than the general population after landing, with Frank Rubio's difficult recovery after 371 days illustrating the pattern.
NASA says the findings matter beyond the ISS because Mars crews could spend nearly three years cycling through microgravity, partial gravity and full Earth gravity without clear data on spinal effects.