Tag Archives: biomechanic expert witness

Biomechanic expert witness Dr. John Lloyd has served attorneys nationwide for 25+ years in biomechanics, human factors, helmet testing and motorcycle accident expert

Truck Accident Reconstruction, Injury Biomechanics and Human Factors

Accidents involving commercial vehicles and truck accident typically involve extensive damage and more severe injuries to vehicle occupants due to the magnitude of forces involved.

Truck Accident Statistics

According to Federal Motor Carrier Safety Administration (FMCSA) data, one person is injured or killed in a truck accident every 10 minutes.
In 2014 there were 213,000 trucking accident resulting in property damage only, 52,000 injury-causing accidents, and 1885 fatal crashes.
About half of all tractor-trailer accidents involve front-end collisions. Back end and side collisions occur in 15 and 12 percent of all crashes, respectively
The top 5 states in which fatal truck accidents occur include Texas, California, Florida, Pennsylvania and Georgia.

Exposure

According to a 2016 AAA report, passenger car drivers spend about 290 hours on the road and travel an average of 10,900 miles each year, with atypical life of a passenger car of 8 years and 150,000 miles. Whereas, tractor-trailer operators may work up to 70 hours per week (55 hours driving time) and often travel 10,000 miles or more in a month. Tractors are typically kept in service for 6 years, during which time they can travel 600,000 miles or more. So, mile-for-mile, a tractor-trailer operator’s exposure is 10-fold that of a passenger car driver.

Who’s at fault?

Nearly 90 percent of all trucking accidents result from human error, rather than mechanical breakdown, equipment failure, bad weather or poor road conditions. Examples of human carelessness or recklessness responsible for causing truck crashes include:

Driving while under the influence of drugs or alcohol
Distracted driving — eating, using cell phones, applying makeup
Driver fatigue
Running red lights, speeding, failing to yield or otherwise violating traffic laws

While some accidents may involve human error on the part of the tractor-trailer operator, trucks and truck drivers are typically held to a higher standard of operation by Federal Laws and Regulations than passenger cars and drivers. Truck drivers need to successfully complete a more extensive driver training program than is required to drive a passenger car. Commercial vehicles are also inspected more thoroughly and on a more frequent basis.

In fact, more than 75% of truck driving accidents are caused by the driver of the passenger vehicle.

Truck Accident Expert

Dr. Lloyd has served as an expert for both defense and plaintiff’s counsel on a number of cases nationwide involving trucking accidents. Dr. Lloyd is uniquely qualified in that he is certified in accident reconstruction, is an internationally-recognized expert in injury biomechanics and can also address the unique human factors issues that affect tractor-trailer operators, such as visual perception and perceived reaction time.

Please call Dr. Lloyd at 813-624-8986 or email DrJohnLloyd@Tampabay.RR.com to discuss how he can be of assistance with your case.

Biomechanical Analysis Athletic Protectors

A male high-school athlete was participating in a team sport when a player from the opposing team attempted a goal. The male athlete was the only obstacle between the opposing player and a winning goal. The high speed shot, taken from less than 10 feet away, impacted the male athlete directly in the groin. He immediately fell to his knees in pain. Thankfully, he was wearing an new athletic protector (known colloquially as a “jockstrap”), which should have prevented injury even at such close quarters. Dr. John Lloyd was retained to perform a biomechanical analysis athletic protector.

The athlete sat out the remainder of the game. Later that evening he became concerned as the swelling continued. The following day tests revealed that amputation of one of his testicles was medically necessary. As a young man, with his whole life ahead of him, the physical and emotional pain of losing a testicle was almost unbearable.

The young man had conducted his research before purchasing the new athletic protector. The packaging had promised comfort and protection. Why then did he sustain this life-changing injury?

Athletic protector biomechanics expert Dr. John Lloyd, was retained to evaluate a potential product liability case.

It was quickly discovered, interestingly, that there are no American Standards on the performance requirements of athletic protectors. Therefore, Dr. Lloyd devised a test method to evaluate exemplars of the subject jockstrap with comparison to models sold by other product manufacturers.

Balls were shot at various speeds from a pitching machine aimed at the athletic protectors affixed to a male mannequin. Each impact was recorded using a high-speed video camera, while Dr. Lloyd’s associate, standing behind the mannequin, measured the speed of each impact using a radar gun. A total of 70 tests were performed.

As the following high-speed video recording shows, the subject athletic protector deforms completely upon impact, providing the wearer with little, if any, protection from injury.

Several new design models also collapsed upon impact, while others cracked and broke

Fortunately, the old style jock strap with which many of us are familiar was among the few models that held up to impact and actually provided adequate protection.

Based on biomechanical analysis I concluded, to a reasonable degree of scientific certainty, that the subject athletic protector provides inadequate protection of the male genitalia from injury associated with impact from a moderate speed ball. This conclusion is based on evidence of extreme deformation of the jock strap upon direct impact from a ball.

Had the manufacturer evaluated their product under real-life conditions, as described herein, they would have learned that this product provides inadequate protection against injury to the male genitalia. Further, comparative testing of other available athletic protectors identified products that provide better protection.

Admissibility of Biomechanics Testimony on Causation of Injury

On the admissibility of biomechanics testimony the Reference Manual on Scientific Evidence, written jointly by the National Academies of Sciences, Engineering and Medicine and the Federal Judicial Center, states: “Specifically, one cross-disciplinary domain deals with the study of injury mechanics, which spans the interface between mechanics and biology. The traditional role of the physician is the diagnosis (identification) of injuries and their treatment, not a detailed assessment of the physical forces and motions that created injuries during a specific event. The field of biomechanics (also called biomechanical engineering) involves the application of mechanical principles to biological systems, and is well suited to answering questions pertaining to injury mechanics.” In the case Garner v Baird [910 N.Y.S.2d 762, 762 (N.Y. Civ. Ct. 2010)] defined biomechanics as “the application of physics and mechanical engineering to the human body.”

In a ruling of the 1st District Court of Appeals of Florida on July 19, 2012 [98 So.3d 115, Florida First District Court of Appeals, 2012] Judge Healey concluded, “that biomechanics expert, Dr. John Lloyd is qualified to offer opinions as to causation because the mechanism of injury fell within the field of biomechanics”. Moreover, in the case of Taylor v Culver Florida First District Court of Appeals, 2015 the appeals court ruling, which directly references Council states “the proffered testimony of the Appellant’s biomechanics expert was relevant to the disputed issues concerning velocity and direction of forces involved in the accident”. In the case Maines v Fox [190 So.3d 1135, Florida First District Court of Appeals, 2016], the ruling states: “Biomechanical opinions as to the general causation of a type of injury are admissible in a personal injury case.”

Biomechanics

Biomechanics (1899) is derived from the Ancient Greek bios “life” and mēchanikē “mechanics”, to refer to the study of the mechanical principles of living organisms, particularly their movement and structure. The earliest known reference to the study of biomechanics dates back to Aristotle (384– 322 BC), who published ‘De Motu Animalium’ (On the Motion of Animals), in which he presented the mechanical concept ‘Ground Action Force’ as a starting point to deliberate where movement comes from.

The science of biomechanics has come a long way since the days of Aristotle. Contemporary biomechanics involves the application of Newtonian mechanics to determine physical capabilities and limitations of the human body. Trauma biomechanics examines whether mechanical forces acting on and within the human body may be sufficient to cause injury. The science of biomechanics is highly accepted by the courts for the purpose of explaining the mechanical causation of injuries.

Biomechanists posses advanced knowledge of human anatomy, mathematics and physics. We use this knowledge to study failure thresholds of human tissue, bone, ligaments, blood vessels, etc. When applying this knowledge to litigation, a biomechanist will perform a reconstruction to determine the forces acting on the plaintiff during the claimed injury-causing event and relate those forces to thresholds of injury. Biomechanists and Medical Doctors serve complementary roles in the medico-legal system. However a biomechanist is uniquely qualified, based on education, training and experience, to determine injury causation.

The methods that I use in my biomechanical evaluations are similar to methods that have been employed by other researchers and are generally accepted by experts in my field. Such methods have been validated and published in peer-reviewed scientific journals.

Expert in Injury Biomechanics

Dr. John Lloyd has served as a biomechanics expert for both defense and plaintiff’s counsel on hundreds of cases throughout the United States involving automobile collisions, motorcycle accidents, trucking crash as well as slips trips and falls. Dr. Lloyd is available to travel to investigate the causes of such cases. Based on his doctorate in ergonomics with a specialization in biomechanics, Dr. Lloyd can assess whether the claimed injuries meet or exceed known biomechanical thresholds of injury.

Biomechanics Laboratory

I utilize a state-of-the-science biomechanics laboratory in my evaluations, as depicted in the following figure. This biomechanics laboratory includes various certified biofidelic mannequins, dedicated test apparatus, data acquisition hardware, software, calibrated sensor instrumentation, professional photography, and high-speed and videography equipment.

Much of my research and work focusses on biomechanical evaluation of helmets, in particular motorcycle and sports helmets, including football and ski helmets.

For helmet testing, we have a standard NOCSAE (National Operating Committee for Standards in Athletic Equipment) head drop system

However, the standard NOCSAE system only measures forces associated with linear acceleration, which are attributed with focal head injuries, such as skull fractures. This system has a rigid neck and therefore cannot measure rotational or angular accelerations, which are associated with traumatic brain injuries, such as concussion and subdural hematomas. We have a modified helmet drop test system, developed in collaboration with the University of Maine, Advanced Manufacturing Center, validation of which has been published in a peer-reviewed journal.

Additionally, the biomechanics laboratory is equipped with the following resources:

Monorail head drop assembly
Twin wire guided drop system (NOCSAE)
Weighted pendulum impactor
Linear bearing table
Height-adjustable, eletromagenetically-controlled freefall drop platform
20,000N impact force plate
880lb ceiling mounted lift system
Certified biofidelic adult headforms
CRABI12 biofidelic infant mannequin
Hybrid III 3-yr old biofidelic mannequin (KSS)
National Instruments 32 channel USB-6343 X-series data acquisition system
LabView 2009 data acquisition software.
Calibrated sensors, including Kistler and PCB Piezotronics tri-axial accelerometers, MEMS triple axis digital gyroscopes, and PCB Piezotronics uni-axial and tri-axial load cells.
Selection of flooring materials, including carpeting, wood and laminates as well as concrete and wood sub-flooring surrogates
Professional still photography equipment
Normal speed and high speed (up to 1kHz) videography equipment
Photography flash and ‘hot’ lighting