Spinal bone mineral after 5 weeks of bed rest
- 71 Downloads
Patients put at bedrest for medical reasons lose 1–2% of spinal bone mineral per week. Losses of this magnitude during even shortterm space flights of a few months would pose a serious limitation and require countermeasures. The spinal bone mineral (L2–L4) was determined in 6 healthy males (precision=2%) before and after 5 weeks of complete bed rest. Only one individual had a significant loss (3%) and the −0.9% mean change for the 6, was not significant (P=0.06). The average negative clacium balance during the 5 weeks was 4 g or 0.36% of total body calcium, similar to that reported in other bed-rest studies. Spinal bone loss, however, in healthy bed-rested males is significantly less than reported for bed-rested patients, suggesting that a large loss of spinal bone mineral does not occur during space flight missions lasting 5 weeks or less.
Key wordsBone mineral Spine Bed rest Calcium balance
Unable to display preview. Download preview PDF.
- 2.Stupakov GP, Kaseykin VS, Kolovskiy AP, Korolev VV (1984) Evaluation of changes in human axial skeletal bone structure during long-term spaceflights. Moscow Kosmicheskaya Biologiya I Aviakosmicheskaya Meditsina 18:33–37Google Scholar
- 5.Smith MC, Rambaut PC, Vogel JM, Whittle MW (1977) Bone mineral measurement—experiment M078. IN: Johnston RS, Dietlein LF (eds) Biomedical results from Skylab. US Government Printing Office, Washington, DC, NASA SP-377, pp. 183–190Google Scholar
- 9.Schneider VS (1981) Modification of negative calcium balance and bone mineral loss during prolonged bed rest. In: NASA Terminal Report, No. T-660-1981, Vol 1–3Google Scholar