A study of side airbag effectiveness in reducing chest injury in car to car side impacts using a FE model

Hayashi S, Yasuki T, Yamamae Y, Takahira Y: A study of side airbag effectiveness in reducing chest injury in car to car side impacts using a FE model. International IRCOBI Research
Conference on the Biomechanics of Impact, Madrid, Spain, September 20-22, 2006, 397-400.

The effect of side airbag in reducing chest injury in car-to-car side impacts was studied using a human FE model (THUMS). A simulation was conducted assuming that a car was struck
by another car at 50 km/h impact speed. Injuries were predicted for both front and rear seat occupants, and compared between cases with and without side airbags. Rib fractures were
observed in the inferior thorax regardless of seating position without side air bags. With side air bags, on the other hand, the number of rib fractures was reduced because of smaller local deformation.

Yet another study showing that side airbags reduce injuries. In my office in Greenbelt, MD we see a fair amount of patients that have been in side impact collisions. Unfortunately, not all of the vehicles involved contain side airbags. It's certainly good to see more and more vehicles with side airbags STANDARD.

-Dr. Louis S. Crivelli II

Chiropractor

Greenbelt, MD

Ultrasound evidence of altered lumbar connective tissue structure in human subjects with chronic low back pain

The lumbar fascia is an often overlooked source of lower back pain. I agree with the author's conclusions that poor movement patterns and chronic inflammation can lead to abnormal fascial structure. As a chiropractor in Greenbelt, I pay special attention to spinal movement patterns as well as fascial tone. With nutrition, I also help each and every patient to decrease the chronic inflammation that seems to be all too common these days.

Background

Although the connective tissues forming the fascial planes of the back have been hypothesized to play a role in the pathogenesis of chronic LBP, there have been no previous studies quantitatively evaluating connective tissue structure in this condition. The goal of this study was to perform an ultrasound-based comparison of perimuscular connective tissue structure in the lumbar region in a group of human subjects with chronic or recurrent low back pain (LBP) for more than 12 months, compared with a group of subjects without LBP.

Methods

In each of 107 human subjects (60 with LBP and 47 without LBP), parasagittal ultrasound images were acquired bilaterally centered on a point 2 cm lateral to the midpoint of the L2-3 interspinous ligament. The outcome measures based on these images were subcutaneous and perimuscular connective tissue thickness and echogenicity measured by ultrasound.

Results

There were no significant differences in age, sex, body mass index (BMI) or activity levels between LBP and No-LBP groups. Perimuscular thickness and echogenicity were not correlated with age but were positively correlated with BMI. The LBP group had ~25% greater perimuscular thickness and echogenicity compared with the No-LBP group (ANCOVA adjusted for BMI, p<0.01>

Conclusion

This is the first report of abnormal connective tissue structure in the lumbar region in a group of subjects with chronic or recurrent LBP. This finding was not attributable to differences in age, sex, BMI or activity level between groups. Possible causes include genetic factors, abnormal movement patterns and chronic inflammation.

Dr. Louis S. Crivelli II

Chiropractor

Greenbelt, MD

Whiplash Injury Prevention

This is a great article regarding the distance of your headrest and whiplash injury. At Laurel Regional Chiropractic, we analyze our patient's headrests and advise them as to the correct distances to minimize injury.


Ivancic PC, Sha D, Panjabi MM. Whiplash injury prevention with active head restraint. Clin Biomech 2009 Nov;24(9):699-707.

Abstract

BACKGROUND: Previous epidemiological studies have observed that an initial head restraint backset greater than 10 cm is associated with a higher risk of neck injury and persistent symptoms. The objective of this study was to investigate the relation between the active head restraint position and peak neck motion using a new human model of the neck.
METHODS: The model consisted of an osteoligamentous neck specimen mounted to the torso of a rear impact dummy and carrying an anthropometric head stabilized with muscle force replication. Rear impacts (7.1 and 11.1g) were simulated with and without the active head restraint. Physiologic rotation was determined from intact flexibility tests. Significant reductions (P<0.05)>0.3 and P<0.001).
FINDINGS: The active head restraint significantly reduced the average peak spinal rotations, however, these peaks exceeded the physiologic range in flexion at head/C1 and in extension at C4/5 through C7/T1. Correlation was observed between the head restraint backset and the extension peaks at C4/5 and C5/6.
INTERPRETATION: Correlation between head restraint backset and spinal rotation peaks indicated that a head restraint backset in excess of 8.0 cm may cause hyperextension injuries at the middle and lower cervical spine. The active head restraint may not be fully activated at the time of peak spinal motions, thus reducing its potential protective effects.

Dr. Louis Crivelli and Dr. Paul Tetro