Journal article
Finite Element Analysis of Patella Alta: A Patellofemoral Instability Model
The Iowa orthopaedic journal, Vol.37, pp.101-108
2017
PMCID: PMC5508303
PMID: 28852343
Appears in Diamond Open Access
Abstract
This study aims to provide biomechanical data on the effect of patella height in the setting of medial patellofemoral ligament (MPFL) reconstruction using finite element analysis. The study will also examine patellofemoral joint biomechanics using variable femoral insertion sites for MPFL reconstruction.
A previously validated finite element knee model was modified to study patella alta and baja by translating the patella a given distance to achieve each patella height ratio. Additionally, the models were modified to study various femoral insertion sites of the MPFL (anatomic, anterior, proximal, and distal) for each patella height model, resulting in 32 unique scenarios available for investigation.
In the setting of patella alta, the patellofemoral contact area decreased, resulting in a subsequent increase in maximum patellofemoral contact pressures as compared to the scenarios with normal patellar height. Additionally, patella alta resulted in decreased lateral restraining forces in the native knee scenario as well as following MPFL reconstruction. Changing femoral insertion sites had a variable effect on patellofemoral contact pressures; however, distal and anterior femoral tunnel malpositioning in the setting of patella alta resulted in grossly elevated maximum patellofemoral contact pressures as compared to other scenarios.
Patella alta after MPFL reconstruction results in decreased lateral restraining forces and patellofemoral contact area and increased maximum patellofemoral contact pressures. When the femoral MPFL tunnel is malpositioned anteriorly or distally on the femur, the maximum patellofemoral contact pressures increase with severity of patella alta.
When evaluating patients with patellofemoral instability, it is important to recognize patella alta as a potential aggravating factor. Failure to address patella alta in the setting of MPFL femoral tunnel malposition may result in even further increases in patellofemoral contact pressures, making it essential to optimize intraoperative techniques to confirm anatomic MPFL femoral tunnel positioning.
Details
- Title: Subtitle
- Finite Element Analysis of Patella Alta: A Patellofemoral Instability Model
- Creators
- Nicole A Watson - Center for Computer Aided Design,University of Iowa,Iowa City, IA 52242Kyle R Duchman - Department of Orthopaedics and Rehabilitation,University of Iowa,Iowa City, IA 52242Nicole M Grosland - Center for Computer Aided Design,University of Iowa,Iowa City, IA 52242Matthew J Bollier - Department of Orthopaedics and Rehabilitation,University of Iowa,Iowa City, IA 52242
- Resource Type
- Journal article
- Publication Details
- The Iowa orthopaedic journal, Vol.37, pp.101-108
- PMID
- 28852343
- PMCID
- PMC5508303
- NLM abbreviation
- Iowa Orthop J
- ISSN
- 1541-5457
- eISSN
- 1555-1377
- Publisher
- Dept. of Orthopaedics, The University of Iowa; United States
- Language
- English
- Date published
- 2017
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Iowa Technology Institute; Orthopedics and Rehabilitation; Injury Prevention Research Center
- Record Identifier
- 9984040365202771
Metrics
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