Estimating patient-specific soft-tissue properties in a TKA knee

Joseph A. Ewing, Michelle K. Kaufman, Erin E. Hutter, Jeffrey F. Granger, Matthew D. Beal, Stephen J. Piazza, Robert A. Siston

Research output: Contribution to journalArticlepeer-review

25 Scopus citations


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.

Original languageEnglish (US)
Pages (from-to)435-443
Number of pages9
JournalJournal of Orthopaedic Research
Issue number3
StatePublished - Mar 1 2016

All Science Journal Classification (ASJC) codes

  • Orthopedics and Sports Medicine


Dive into the research topics of 'Estimating patient-specific soft-tissue properties in a TKA knee'. Together they form a unique fingerprint.

Cite this