Computational Biomechanics Research Projects

A NOVEL MEDICAL DEVICE DESIGN FOR LUMBAR SPINAL STENOSIS (LSS) 

Lumbar spinal stenosis (LSS) is a medical condition in which the spinal canal narrows and compresses the spinal cord and nerves at the level of the lumbar vertebra. Minimally-invasive methods including XSTOP are still questionable on the fatigue life of these devices and the limitation about protecting nerve. The design includes a nitinol coil to be delivered minimally-invasively that uses body heat to initiate a transformation from a straight shape to the coiled design around the nerve root. The central hypothesis of this research is that development of a much smaller device utilizing the shape memory effects of nitinol alloys and implanted in a minimally-invasive manner could prove to be a novel alternative to current standards of treatment. The object of this study is to design a device which could prove to be a novel alternative to current standards of treatment via using computational prediction and experiments validation. The experiments data can provide nerve root pressure difference between intact and damaged spine in order to allow our device protect patients from low back pain. A validated and geometrical accurate FE model is created to predict the response of lumber spine (with the device for treatment of LSS) and optimize device design.

HUMAN KNEE JOINT MODELING AND ACL INJURY MECHANISM STUDY

As the largest joint in the human body, the knee is considered the most complicated and vulnerable one because it has complex structure anatomically and it bears enormous weight and pressure loads while providing flexible movement. Finite element (FE) modeling and simulations of the knee joint are useful for analyzing knee joint kinematics. They can provide valuable insights into the mechanisms of sported-related knee injury including anterior cruciate ligament (ACL) injury and meniscus tear. Our on-going project mainly focuses on the ACL injuries in high demand sports like soccer, football, and basketball. The geometry of knee components are reconstructed from MRI and CT. The materials properties of the tissues, ligaments and cartilages that make up the knee will be obtained from experimental tests. We expect our model enables us to understand the injury mechanism quantitatively and more profoundly.

PRESSURE MEASUREMENT FOR APPLICATIONS IN SPORTS MEDICINE

Non-contact lower extremity injuries are prevalent in high level athletics. Pedar is a dynamic in-shoe pressure measuring system for monitoring local loads between the foot and the shoe.  The large scope of this research agenda is to determine if the Pedar pressure measurement system can be utilized during selected functional tasks and during real-time athletic activities to predict risk of injury.  Functional Movement Screen (FMS) is a screening tool used to identify limitations and asymmetries in specific fundamental movements. One part of the study is to collect baseline Pedar data on college athletes of both genders doing three different FMS movements to test the reliability and validity of Pedar Functional Screening tests. We are also comparing Functional Movement Screening scoring of overhead squat with pressure loading data using Pedar. In addition, we are using the Pedar system to evaluate the effects of fatigue on performance of overhead squat, single leg squat, and forward step down measures.