Biomechanics
The physics of human injury.
Did the Forces Cause the Injury?
Biomechanics applies the laws of physics to the human body to determine injury mechanisms and whether they are consistent with the event. Aperture’s biomechanical experts analyze the loading, occupant motion, and injury mechanisms in an incident and compare them against known human tolerances, explaining whether the injuries claimed make physical sense, and why or why not. Much of this work involves motor vehicle crashes, but the same analysis applies to other impact and human-motion events. We provide objective analysis and expert testimony for attorneys and insurers on either side of a claim.
Occupant Injury & Crash Biomechanics
Analysis of how occupants move and load during a crash, and whether the forces involved are consistent with the injuries claimed. Includes occupant kinematics, restraint use, and low-speed, rear-end, side, and frontal impact configurations.
Injury Causation & Human Tolerance
Comparison of the forces in an event against known human tolerances to determine whether a specific injury could occur. Includes spinal trauma, traumatic brain injury, upper- and lower-extremity injuries, and slip, trip, and fall biomechanics.
Testing & Measurement
Instrumented testing and measurement to quantify forces and human response. Includes crash testing with anthropomorphic test devices and human volunteers, motion capture, gait analysis, and force-plate measurement.
Related practices: Biomechanics works hand in hand with Accident Reconstruction on crash cases and supports Premises Liability and Human Factors.
Our Capabilities
Biomechanical experts can analyze the magnitude and direction at which force is applied to human subjects to determine injury potential for all types of human motion and impact dynamics, not just motor vehicle accidents. For example, cases may include, but are not limited to, pedestrian accidents such as slips, trips, and falls of both the subject themselves and objects onto the subject.
Rear impact dummies (RID) mimic the motion of the human spine in rear-end impacts. With hinges at each level of the vertebrae, the articulated spine of the BioRID-II directly measures the internal forces and moments on the human spine, pelvis, and femur that could not otherwise be tested on a live human at higher speeds for rear-end impacts.
To assess occupant injury potential for a traumatic brain injury (TBI), biomechanical experts analyze both the linear and rotational acceleration and angular velocity at the head, as well as the sheer forces acting at the base of the skull and top of the cervical vertebral column, in crash testing.
The Hybrid III dummy meets the National Highway Transport and Safety Administration (NHTSA) federal motor vehicle safety standards for its New Car Assessment Program (NCAP). It provides valid data to assess occupant injuries in humans when testing motor vehicle crashes and other practical applications.
Human ambulation analysis can be performed from video, motion capture, and measurement of the ground reaction force via a Kistler force plate. It can help determine whether a unique gait exists such that it can contribute to an accident and if a pedestrian favors one side during ambulation, thus increasing the amount of wear and tear on the adjacent extremity.
Using Madymo and LS-DYNA®, the best occupant simulators available on the market, motor vehicle rollover analysis accurately determines occupant injury potential. It is the safest way to test the kinetics and kinematics acting on an occupant in a rollover motor vehicle accident.
For motor vehicle accidents that occurred at higher speeds (e.g. above 10 mph), occupant kinematics, applied forces, and injury mechanisms can be used to assess the forces applied to the occupants in higher energy impacts such as airbag deployments and rollovers. The force of impact on the occupants is established at multiple levels through vehicular reconstruction to assess bodily injury.
Biomechanics and occupant injury potential can be assessed in motor vehicle accidents at low speeds (e.g. 5-10 mph). By examining occupant kinematics, applied forces, and injury mechanisms in low-speed, rear-end, lateral, sideswipe, and frontal motor vehicle accidents, biomechanical experts can determine whether the magnitude and direction at which forces were applied to the occupants make sense for the injuries claimed.
Slip, trip, and fall analysis is conducted for such premise liability cases. For slips, biomechanical experts measure the slip resistance of a surface walkway. For trips, they measure the vertical change in elevation to determine whether it is pursuant to code or against surface standards.
Spinal trauma analysis evaluates the linear forces and bending moments applied to the spine to determine whether they exceed known tolerances. If the applied forces and moments exceed the strength of the intervertebral discs, then its nucleus can herniate and cause severe pain and a lack of muscular motion.
Thoracic trauma injury analysis assesses occupant injury potential of the thorax, which is typically less prone to injury due to the rigid support of the ribcage.
Upper and lower extremity injury analysis looks at the magnitude and direction of force applied to the shoulders, elbows, wrists, knees, ankles, and feet in an accident. Occupant injury potential can be determined by testing whether the force applied to these extremities exceeds their known tolerances and compromises their structure.
Key Experts
Related Insights
The Biomechanical Effects of Neck and Back Cushion/Pillow/Support Devices in Low-Speed Rear Impacts
Estimation of Seated Driver Eye Height Based on Standing Height, Weight, Seatback Angle, and Seat Bottom Angle
Validation of Utilizing a Self-Propelled Crash Sled to Simulate Occupant Accelerations in Minor Rear-End Impacts
Frequently Asked Questions
The answer depends on the question. Accident reconstruction determines how the event occurred, including vehicle motion, impact, and sequence. A biomechanical expert evaluates how the forces acted on the human body and whether they are consistent with the claimed injury. Many cases require both disciplines. Aperture coordinates reconstruction and biomechanics when the physical event and injury causation must be analyzed together.
Biomechanical analysis can evaluate whether the magnitude, direction, and duration of the forces in an incident are consistent with a claimed injury mechanism. Aperture’s experts compare occupant motion and loading with known human tolerances and the characteristics of the event. The expert does not replace medical diagnosis. Instead, the analysis addresses whether the physics of the incident are compatible with the injury claim and explains the basis for that opinion.
Aperture’s biomechanics work includes spinal trauma, traumatic brain injury, upper- and lower-extremity injuries, occupant motion, restraint use, slips, trips, falls, rollovers, and low-speed, rear-end, side, and frontal impacts. The same principles can apply to other human-motion and impact events. The expert’s qualifications should match the specific mechanism, body region, testing method, and opinions required in the matter.
No. Some matters can be evaluated using incident data, medical records, reconstruction results, published research, and established human-tolerance information. Other cases may benefit from instrumented testing, crash testing, motion capture, gait analysis, force-plate measurement, or occupant simulation. The expert should select methods that address the disputed question and explain why the testing or analytical approach is appropriate for the available evidence.
Yes. Aperture’s biomechanical experts provide objective analysis for attorneys and insurers on either side of a claim. The opinion should follow the evidence and the applicable science rather than the retaining party’s preferred outcome. A well-supported expert analysis should identify the assumptions used, explain any limitations, and distinguish between what the data supports, what remains uncertain, and what falls outside the expert’s discipline.