1
|
Rivas DJ, Aitken HD, Dibbern KN, Willey MC, Westermann RW, Goetz JE. Incorporating patient-specific hip orientation from weightbearing computed tomography affects discrete element analysis-computed regional joint contact mechanics in individuals treated with periacetabular osteotomy for hip dysplasia. Proc Inst Mech Eng H 2024; 238:237-249. [PMID: 38229467 PMCID: PMC10985972 DOI: 10.1177/09544119231221023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Computational models of the hip often omit patient-specific functional orientation when placing imaging-derived bony geometry into anatomic landmark-based coordinate systems for application of joint loading schemes. The purpose of this study was to determine if this omission meaningfully alters computed contact mechanics. Discrete element analysis models were created from non-weightbearing (NWB) clinical CT scans of 10 hip dysplasia patients (11 hips) and oriented in the International Society of Biomechanics (ISB) coordinate system (NWB-ISB). Three additional models were generated for each hip by adding patient-specific stance information obtained via weightbearing CT (WBCT) to each ISB-oriented model: (1) patient-specific sagittal tilt added (WBCT-sagittal), (2) coronal and axial rotation from optical motion capture added to (1; WBCT-combo), and (3) WBCT-derived axial, sagittal, and coronal rotation added to (1; WBCT-original). Identical gait cycle loading was applied to all models for a given hip, and computed contact stress and contact area were compared between model initialization techniques. Addition of sagittal tilt did not significantly change whole-joint peak (p = 0.922) or mean (p = 0.871) contact stress or contact area (p = 0.638). Inclusion of motion-captured coronal and axial rotation (WBCT-combo) decreased peak contact stress (p = 0.014) and slightly increased average contact area (p = 0.071) from WBCT-sagittal models. Including all WBCT-derived rotations (WBCT-original) further reduced computed peak contact stress (p = 0.001) and significantly increased contact area (p = 0.001). Variably significant differences (p = 0.001-1.0) in patient-specific acetabular subregion mechanics indicate the importance of functional orientation incorporation for modeling applications in which local contact mechanics are of interest.
Collapse
Affiliation(s)
- Dominic J.L. Rivas
- Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, 52242, USA
- Department of Biomedical Engineering, University of Iowa, Iowa City, IA, 52242, USA
| | - Holly D. Aitken
- Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, 52242, USA
| | - Kevin N. Dibbern
- Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, 52242, USA
| | - Michael C. Willey
- Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, 52242, USA
| | - Robert W. Westermann
- Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, 52242, USA
| | - Jessica E. Goetz
- Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, 52242, USA
- Department of Biomedical Engineering, University of Iowa, Iowa City, IA, 52242, USA
| |
Collapse
|