(January 2022) - Across the United States, an increasing number of low impact collisions are ending up in litigation, with plaintiffs frequently alleging in excess of $50,000 in past medical expenses and often with surgical recommendations. Claims that used to have an emergency room visit and a little chiropractic treatment now have multiple epidural steroid injections, MRIs, and spinal fusion surgery recommendations. To defend this new crop of low impact/high medical claims, the proper use of a good biomechanical expert is an effective way to show the jury the severity of the impact.

Impact severity is typically measured using the "Delta-V," which is the change in velocity. There have been cases involving a Delta-V as low 1.1 mph with claims of future medical expenses in the hundreds of thousands of dollars. Several studies over the years have measured the physical responses in adults using different changes in velocity in frontal impacts, as illustrated in the graph below.


Frontal impacts using volunteers1

The Delta-V of a particular collision can be compared to these studies to determine the likelihood of a person sustaining a spinal injury at that change in velocity.

In some jurisdictions, photos of vehicle damage in low impact cases are not admissible unless you have a biomechanical expert who relies on the photos for their opinions. For those jurisdictions, a biomechanical expert is required to have the low impact photos seen by the jury.

With ever increasing medicals in all claims, biomechanical experts have become an essential tool to combat inflated medical treatment and expenses. In Texas, Lewis Brisbois' Transportation attorneys have received objective biomechanical information from Biodynamic Research Corporation (brconline.com).


1 FN1: Deng B, Melvin J, Rouhana S. Head neck kinematics in dynamic forward flexion. In: Vol 983156. Society for Automotive Engineering; 1998; Mertz H, Patrick L. Strength and Response of the Human Neck.; 1971; Bailey MN, Wong BC, Lawrence JM. Data and Methods for Estimating the Severity of Minor Impacts. In: ; 1995. doi:10.4271/950352; Beeman SM, Kemper AR, Madigan ML, Duma SM. Effects of Bracing on Human Kinematics in Low-Speed Frontal Sled Tests. Ann Biomed Eng. 2011; Fugger TF, Randles BC, Welcher JB, Szabo TJ. Vehicle and Occupant Kinematics in Low-Speed Override/Underride Collisions. SAE Technical Paper; 2003; Goodwin V, Martin D, Sackett R. Vehicle and occupant response in low-speed car to barrier override impacts. Accid Reconstr Technol Animat. 1999;(SP-1407); Siegmund G, Williamson P. Speed change of amusement park bumper cars. In: 1993:299-308.

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