How Can a Biomechanical Engineer Assist Attorneys in Medical Malpractice Cases?
Michael Hill, Ph.D., P.E. | Biomechanics | Qforensics.com
Medical malpractice cases often involve complex medical records, technical evidence, and disputed opinions about how an injury occurred. Physicians provide valuable insights into diagnosis and treatment. Biomechanical engineers offer a different perspective by analyzing the physical forces, movements, and mechanical events involved in an injury occurring during a medical procedure. Their expertise can help attorneys evaluate whether the alleged medical negligence could have led to the claimed injuries.
In this article, we'll explore how a biomechanical engineer assists attorneys in medical malpractice cases, the types of analyses they perform – including several case studies – and why their testimony can strengthen a legal strategy.
Biomechanical Engineering
Biomechanical engineers are often employed in the medical device field by device manufacturers, government regulatory agencies such as the Food and Drug Administration (FDA), universities, or hospital complexes involved in clinical trials. Biomechanical engineers typically work alongside physicians. Whereas physicians explain diagnoses, treatment decisions, and the applicable medical standard of care, biomechanical engineers explain the underlying physical mechanics of the injury.
Biomechanical engineers perform laboratory tests, dissections, and computer simulations of various human body segments to understand which movements will stretch and stress muscles, tendons, ligaments, and other tissues. The design of orthopedic implants is performed by those knowledgeable in biomechanics, as both the forces that will be applied to the implants and the strength of the implants to withstand these forces must be known during the design and development phases. In cardiovascular applications, which primarily involve the heart and blood vessels, biomechanical engineers develop artificial hearts, heart valves, stents, catheters, and devices for treating aneurysms and removing blood clots. Most biomechanical engineers have education and training in the broader field of biomedical engineering, and they also work in other medical fields, such as neurophysiology, which focuses on understanding the electrical signals in the brain, spinal cord, and nerves.
Biomechanics research is applied in identifying mechanisms of injury and the subsequent analysis of injury mitigation strategies. In trauma biomechanics, mechanical principles are used to understand how injuries occur to bones, joints, organs, and tissues.
The Role of a Biomechanical Engineer in Medical Malpractice Cases
Biomechanical engineering is the application of mechanical engineering principles to biological systems, particularly the human body. Biomechanical engineers use mathematical modeling, computer simulations, imaging studies, laboratory testing, and published scientific literature to evaluate injury mechanisms. Unlike physicians, biomechanical engineers generally do not diagnose medical conditions or determine whether a physician met the applicable standard of care. Instead, they analyze whether the physical evidence is consistent with the alleged mechanism of injury and whether the claimed injury could reasonably have resulted from a specific event.
Medical malpractice litigation often centers on proving four essential elements:
- Duty of care
- Breach of the standard of care
- Consistency
- Damages
While physicians typically testify regarding the diagnosed medical condition or the standard of care, biomechanical engineers primarily address whether the mechanics of an event are consistent with the injuries claimed. Biomechanical engineers use mathematical modeling, computer simulations, imaging studies, laboratory testing, and the published scientific literature to evaluate injury mechanisms.
Below are several case studies based on real-world incidents in which a biomechanical engineer was retained:
Case 1: Sciatic Nerve Injuries during Hip Replacement Surgery
“Foot drop” refers to the difficulty in lifting the front part of the foot, which can occur from damage to the sciatic nerve. Such nerve damage may occur during hip replacement surgery, where the sciatic nerve can be compressed by the retractor used to access the hip. This compression may directly damage the nerve, and the forces can be increased due to tension on the nerve as it is pulled away from its tether at the knee.
After undergoing hip replacement surgery, a female patient complained of foot drop. A forensic biomechanical engineer was retained to investigate the case. As part of the investigation, the engineer:
- Inspected the hip retractor
- Reviewed the medical records provided
- Examined peer-reviewed literature on the biomechanical forces involved during hip replacement surgeries.
- Determined what the forces likely were during the procedure and how they were related to the failure strength of the sciatic nerve and its proximal divisions towards the knee.
The investigation concluded that retraction forces pose a known risk for sciatic nerve injury, and the forces involved did not exceed what is reasonably expected during this procedure. Moreover, clinical studies have shown a high incidence of foot drop following successful hip replacement surgeries. Sciatic nerve damage is a known risk and consistent with the forces typically applied during hip replacement surgeries. In this case, the biomechanical engineer determined, by using the laws of physics and mechanical principles, that the orthopedic surgeon did not have to apply unreasonably high forces for the injury to occur.
Case 2: Abdominal Injury during Laparoscopic Procedure
A female patient experienced severe complications following a laparoscopic gastric bypass procedure. During the surgery, a pneumoperitoneum was created using a Veress needle, which involves injecting carbon dioxide into the abdominal cavity to separate the abdominal wall from the internal organs for better visualization. However, the pneumoperitoneum could not be maintained, leading the surgical team to resort to open abdominal surgery. Subsequently, the patient developed problems related to a perforated bowel. The plaintiff claimed that the failure of the Veress needle led to the bowel perforation.
The retained biomechanical engineer:
- Performed a joint inspection of the subject Veress needle
- Inspected the system used to insufflate the abdomen during the procedure
- Procured and tested an exemplar needle
The inspection revealed no issues with the device, and the exemplar needle functioned correctly. A review of the literature and FDA documentation, including the design history file (DHF), showed no regulatory compliance issues. The biomechanical engineer concluded that there were no problems with the medical devices involved and that the bowel damage was consistent with either the insertion of the Veress needle, which is a known risk of laparoscopic surgery, or the subsequent open abdominal surgery.
Case 3: Artery Injury during Endovascular Coiling Procedure
A patient presented to a neuroendovascular surgeon with a large cerebral (brain) aneurysm in the posterior communicating artery. The surgeon attempted a coiling procedure in which a catheter was inserted into the femoral artery and advanced to the Circle of Willis through a carotid artery. During deployment of the thin platinum coils into the aneurysm, some of the coils deployed into the catheter. When the surgeon attempted to retrieve the misplaced coil by pulling on the catheter, it resulted in damage to the walls of the carotid siphon, which is the twisted segment of the carotid artery in the neck, leading to the development of a pseudoaneurysm. A biomechanical engineer reviewed the available documentation and information related to the procedure. The engineer concluded that the mechanical failure of the device prevented it from being retrieved, resulting in the damage to the arterial wall. Therefore, the issue was attributed to the medical device itself, not the surgeon or surgical procedure, which was consistent with the damage to the carotid artery.
Summary
Biomechanical engineers play a crucial role in medical malpractice litigation by providing objective, science-based analysis of injury mechanisms and causation. Their expertise helps attorneys evaluate complex evidence, reconstruct medical events, assess the plausibility of injury claims, and their testimony can simplify highly technical concepts for judges and juries while supporting evidence-based conclusions.
By collaborating with physicians and legal professionals, biomechanical engineers contribute to a more comprehensive understanding of how injuries occurred, assisting attorneys in building stronger cases supported by engineering principles and factual evidence. Whether investigating patient falls, orthopedic injuries, surgical positioning injuries, or medical device failures, their analysis can be instrumental in achieving fair and informed legal outcomes.
About the Author
Michael Hill, Ph.D., P.E., is a Biomechanical Engineer at Quality Forensic Engineering, LLC. His background is in cardiovascular and orthopedic biomechanics, injury consistency analysis, mechanical design, instrumentation, and experimental analysis. Dr. Hill’s doctoral dissertation topic was on brain aneurysm and artery wall biomechanics, and he has worked with neuroendovascular surgeons on research projects aimed at improving medical devices and techniques. He also performed laboratory work with orthopedic surgeons that resulted in techniques to help alleviate sciatic nerve injuries during open hip surgery. Dr. Hill has lectured at universities, and his research findings have been published in 17 academic articles. He has presented at over 40 international and national scientific conferences and his work has been extensively cited by others. His primary focus is on injury consistency analysis, for both plaintiff and defense cases.
