TY - JOUR
T1 - Short applications of very low-magnitude vibrations attenuate expansion of the intervertebral disc during extended bed rest
AU - Holguin, Nilsson
AU - Muir, Jesse
AU - Rubin, Clinton
AU - Judex, Stefan
N1 - Funding Information:
We would like to thank Dr Janice Meck, Sherlene Dryer, Robert Pietrzyk, and the entire NASA JSC and UTMB bed rest team for their invaluable contributions. Technical assistance with the MRI and CT measurements by Dr. Mark Wagshul, Dr. Harlan Evans, and Dennis Dornfest was greatly appreciated. We are also grateful for the financial support from NSBRI (BL00802) and NASA (NNJ04HI06G), and the NASA Flight Analogs/Bed Rest Research Project.
PY - 2009/6
Y1 - 2009/6
N2 - Background context: Loss of functional weightbearing during spaceflight or extended bed rest (BR) causes swelling of the lumbar intervertebral discs (IVDs), elongates the spine, and increases the incidence of low back pain (LBP). Effective interventions for the negative effects of unloading are critical but not yet available. Purpose: To test the hypothesis that high-frequency, low-magnitude mechanical signals (LMMS) can attenuate the detrimental morphologic changes in the lumbar IVDs. Study design/setting: Volunteers were subjected to 90d of BR and 7d of reambulation. While retaining this supine position, 18 random subjects received LMMS (30 Hz) for 10 min/d, at peak-to-peak acceleration magnitudes of either 0.3 g (n=12) or 0.5 g (n=6). The remaining subjects served as controls (CTRs). Patient sample: Eighteen males and 11 female (33±7 y) healthy subjects of astronaut age (35±7 y, 18 males, 11 females) and without a history of back pain participated in this study. Outcome measures: A combination of magnetic resonance imaging and computed tomography scans of the lumbar spine of all subjects were taken at baseline, 60d, 90d, and 7d post-BR. Back pain was self-reported. Methods: IVD morphology, spine length, and back pain were compared between CTR and LMMS subjects. Results: Compared with untreated CTRs, LMMS attenuated mean IVD swelling by 41% (p<.05) at 60d and 30% (p<.05) at 90d. After 7 days of reambulation, disc volume of the CTR group was still 8% (p<.01) greater than at baseline, whereas that for the LMMS group returned the disc volume to baseline levels. In contrast to BR alone, LMMS also retained disc convexity at all time points and reduced the incidence of LBP by 46% (p<.05). Conclusions: These data indicate that short daily bouts of LMMS can mitigate the detrimental changes in disc morphology, which arise during nonweightbearing, and provides preliminary support for a novel means of addressing spinal deterioration both on earth and in space.
AB - Background context: Loss of functional weightbearing during spaceflight or extended bed rest (BR) causes swelling of the lumbar intervertebral discs (IVDs), elongates the spine, and increases the incidence of low back pain (LBP). Effective interventions for the negative effects of unloading are critical but not yet available. Purpose: To test the hypothesis that high-frequency, low-magnitude mechanical signals (LMMS) can attenuate the detrimental morphologic changes in the lumbar IVDs. Study design/setting: Volunteers were subjected to 90d of BR and 7d of reambulation. While retaining this supine position, 18 random subjects received LMMS (30 Hz) for 10 min/d, at peak-to-peak acceleration magnitudes of either 0.3 g (n=12) or 0.5 g (n=6). The remaining subjects served as controls (CTRs). Patient sample: Eighteen males and 11 female (33±7 y) healthy subjects of astronaut age (35±7 y, 18 males, 11 females) and without a history of back pain participated in this study. Outcome measures: A combination of magnetic resonance imaging and computed tomography scans of the lumbar spine of all subjects were taken at baseline, 60d, 90d, and 7d post-BR. Back pain was self-reported. Methods: IVD morphology, spine length, and back pain were compared between CTR and LMMS subjects. Results: Compared with untreated CTRs, LMMS attenuated mean IVD swelling by 41% (p<.05) at 60d and 30% (p<.05) at 90d. After 7 days of reambulation, disc volume of the CTR group was still 8% (p<.01) greater than at baseline, whereas that for the LMMS group returned the disc volume to baseline levels. In contrast to BR alone, LMMS also retained disc convexity at all time points and reduced the incidence of LBP by 46% (p<.05). Conclusions: These data indicate that short daily bouts of LMMS can mitigate the detrimental changes in disc morphology, which arise during nonweightbearing, and provides preliminary support for a novel means of addressing spinal deterioration both on earth and in space.
KW - Bed rest
KW - Biomechanical countermeasure
KW - High-frequency mechanical stimuli
KW - Intervertebral disc
KW - Swelling
KW - Vibrations
UR - http://www.scopus.com/inward/record.url?scp=67349160417&partnerID=8YFLogxK
U2 - 10.1016/j.spinee.2009.02.009
DO - 10.1016/j.spinee.2009.02.009
M3 - Article
C2 - 19356986
AN - SCOPUS:67349160417
SN - 1529-9430
VL - 9
SP - 470
EP - 477
JO - Spine Journal
JF - Spine Journal
IS - 6
ER -