PMID- 33253414
OWN - NLM
STAT- MEDLINE
DCOM- 20210809
LR  - 20220208
IS  - 1523-4681 (Electronic)
IS  - 0884-0431 (Print)
IS  - 0884-0431 (Linking)
VI  - 36
IP  - 4
DP  - 2021 Apr
TI  - Patterns of Load-to-Strength Ratios Along the Spine in a Population-Based Cohort 
      to Evaluate the Contribution of Spinal Loading to Vertebral Fractures.
PG  - 704-711
LID - 10.1002/jbmr.4222 [doi]
AB  - Vertebral fractures (VFx) are common among older adults. Epidemiological studies 
      report high occurrence of VFx at mid-thoracic and thoracolumbar regions of the 
      spine; however, reasons for this observation remain poorly understood. Prior 
      reports of high ratios of spinal loading to vertebral strength in the 
      thoracolumbar region suggest a possible biomechanical explanation. However, no 
      studies have evaluated load-to-strength ratios (LSRs) throughout the spine for a 
      large number of activities in a sizeable cohort. Thus, we performed a 
      cross-sectional study in a sample of adult men and women from a population-based 
      cohort to: 1) determine which activities cause the largest vertebral LSRs, and 2) 
      examine patterns of LSRs along the spine for these high-load activities. We used 
      subject-specific musculoskeletal models of the trunk to determine vertebral 
      compressive loads for 109 activities in 250 individuals (aged 41 to 90 years, 50% 
      women) from the Framingham Heart Study. Vertebral compressive strengths from T(4) 
      to L(4) were calculated from computed tomography-based vertebral size and bone 
      density measurements. We determined which activities caused maximum LSRs at each 
      of these spinal levels. We identified nine activities that accounted for >95% of 
      the maximum LSRs overall and at least 89.6% at each spinal level. The activity 
      with the highest LSR varied by spinal level, and three distinct spinal regions 
      could be identified by the activity producing maximum LSRs: lateral bending with 
      a weight in one hand (upper thoracic), holding weights with elbows flexed (lower 
      thoracic), and forward flexion with weight (lumbar). This study highlights the 
      need to consider a range of lifting, holding, and non-symmetric activities when 
      evaluating vertebral LSRs. Moreover, we identified key activities that produce 
      higher loading in multiple regions of the spine. These results provide the first 
      guidance on what activities to consider when evaluating vertebral 
      load-to-strength ratios in future studies, including those examining dynamic 
      motions and the biomechanics of VFx. (c) 2020 American Society for Bone and Mineral 
      Research (ASBMR).
CI  - (c) 2020 American Society for Bone and Mineral Research (ASBMR).
FAU - Mokhtarzadeh, Hossein
AU  - Mokhtarzadeh H
AUID- ORCID: 0000-0002-6519-7735
AD  - Department of Biomedical Engineering, Melbourne School of Engineering, The 
      University of Melbourne, Melbourne, Australia.
FAU - Anderson, Dennis E
AU  - Anderson DE
AUID- ORCID: 0000-0002-5171-7445
AD  - Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, 
      Boston, MA, USA.
AD  - Department of Orthopedic Surgery, Harvard Medical School, Boston, MA, USA.
FAU - Allaire, Brett T
AU  - Allaire BT
AD  - Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, 
      Boston, MA, USA.
FAU - Bouxsein, Mary L
AU  - Bouxsein ML
AUID- ORCID: 0000-0002-7027-7414
AD  - Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, 
      Boston, MA, USA.
AD  - Department of Orthopedic Surgery, Harvard Medical School, Boston, MA, USA.
AD  - Harvard-MIT Health Sciences and Technology Program, Cambridge, MA, USA.
LA  - eng
GR  - 75N92019D00031/HL/NHLBI NIH HHS/United States
GR  - R00 AG042458/AG/NIA NIH HHS/United States
GR  - R01 AR073019/AR/NIAMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
DEP - 20201213
PL  - England
TA  - J Bone Miner Res
JT  - Journal of bone and mineral research : the official journal of the American 
      Society for Bone and Mineral Research
JID - 8610640
SB  - IM
MH  - Aged
MH  - Bone Density
MH  - Compressive Strength
MH  - Cross-Sectional Studies
MH  - Female
MH  - Humans
MH  - Lumbar Vertebrae/diagnostic imaging
MH  - Male
MH  - *Spinal Fractures/diagnostic imaging/epidemiology
MH  - *Spine/diagnostic imaging
PMC - PMC8383210
MID - NIHMS1719028
OTO - NOTNLM
OT  - BIOMECHANICS
OT  - BONE QCT
OT  - FRACTURE PREVENTION
OT  - FRACTURE RISK ASSESSMENT
OT  - OSTEOPOROSIS
COIS- Disclosures All authors state that they have no conflicts of interest.
EDAT- 2020/12/01 06:00
MHDA- 2021/08/10 06:00
PMCR- 2021/08/24
CRDT- 2020/11/30 17:14
PHST- 2020/11/12 00:00 [revised]
PHST- 2020/08/12 00:00 [received]
PHST- 2020/11/19 00:00 [accepted]
PHST- 2020/12/01 06:00 [pubmed]
PHST- 2021/08/10 06:00 [medline]
PHST- 2020/11/30 17:14 [entrez]
PHST- 2021/08/24 00:00 [pmc-release]
AID - 10.1002/jbmr.4222 [doi]
PST - ppublish
SO  - J Bone Miner Res. 2021 Apr;36(4):704-711. doi: 10.1002/jbmr.4222. Epub 2020 Dec 
      13.