Estimating patient-specific soft-tissue properties in a TKA knee.
Surgical technique is one factor that has been identified as critical to success of total knee arthroplasty. Researchers have shown that computer simulations can aid in determining how decisions in the operating room generally affect post-operative outcomes. However, to use simulations to make clinically relevant predictions about knee forces and motions for a specific total knee patient, patient-specific models are needed. This study introduces a methodology for estimating knee soft-tissue properties of an individual total knee patient. A custom surgical navigation system and stability device were used to measure the force-displacement relationship of the knee. Soft-tissue properties were estimated using a parameter optimization that matched simulated tibiofemoral kinematics with experimental tibiofemoral kinematics. Simulations using optimized ligament properties had an average root mean square error of 3.5° across all tests while simulations using generic ligament properties taken from literature had an average root mean square error of 8.4°. Specimens showed large variability among ligament properties regardless of similarities in prosthetic component alignment and measured knee laxity. These results demonstrate the importance of soft-tissue properties in determining knee stability, and suggest that to make clinically relevant predictions of post-operative knee motions and forces using computer simulations, patient-specific soft-tissue properties are needed.
Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio.
Joseph A
JA
Ewing
Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio.
Michelle K
MK
Kaufman
Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio.
Erin E
EE
Hutter
Department of Orthopaedics, The Ohio State University, Columbus, Ohio.
Jeffrey F
JF
Granger
Department of Orthopedic Surgery, Northwestern University, Evanston, Illinois.
Matthew D
MD
Beal
Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania.
Stephen J
SJ
Piazza
Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio.|Department of Orthopaedics, The Ohio State University, Columbus, Ohio.
Robert A
RA
Siston
D000328:Adult; D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D003198:Computer Simulation; D005260:Female; D006801:Humans; D007717:Knee / Q000502:physiology*; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D057285:Precision Medicine
ligament properties; optimization; patient-specific; simulation; total knee arthroplasty