Quantification of tibiofemoral shear and compressive loads using a MRI-based EMG-driven knee model.
The purpose of this study is to describe an MRI-based EMG-driven knee model to quantify tibiofemoral compressive and shear forces. Twelve healthy females participated. Subjects underwent 2 phases of data collection: (1) MRI assessment of the lower extremity to quantify muscle volumes and patella tendon orientation and (2) biomechanical evaluation of a drop-jump task. A subject-specific EMG-driven knee model that incorporated lower extremity kinematics, EMG, and muscle volumes and patella tendon orientation estimated from MRI was developed to quantify tibiofemoral shear and compressive forces. A resultant anterior tibial shear force generated from the ground reaction force (GRF) and muscle forces was observed during the first 30% of the stance phase of the drop-jump task. All of the muscle forces and GRF resulted in tibiofemoral compression, with the quadriceps force being the primary contributor. Acquiring subject-specific muscle volumes and patella tendon orientation for use in an EMG-driven knee model may be useful to quantify tibiofemoral forces in persons with altered patella position or muscle atrophy following knee injury or pathology.
Division of Biokinesiology and Physical Therapy, University of Southern California., Los Angeles, CA, USA.
Liang-Ching
LC
Tsai
Irving S
IS
Scher
Christopher M
CM
Powers
D000328:Adult; D001696:Biomechanical Phenomena; D019245:Compressive Strength; D004576:Electromyography; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D035002:Lower Extremity / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D017847:Patellar Ligament / Q000502:physiology*; D011312:Pressure; D033081:Shear Strength