Selected Papers from the 2015 European Knee Society MeetingBiomechanical Effects of Different Varus and Valgus Alignments in Medial Unicompartmental Knee Arthroplasty
Section snippets
Native Knee Model Definition
A right leg from a 43-year-old woman was considered to represent the geometric native knee model. The anatomic structures were reconstructed from the patient's scans obtained both by magnetic resonance imaging and by computed tomography. Before reconstruction, medical records of the subject showed no case of musculoskeletal disorder nor problems of limb alignment; thus, the investigated knee was considered healthy.
The images were imported in an image processing software (Mimics 17.0;
Results
The load distribution between the medial and lateral compartments of the tibiofemoral joint was measured for the native knee first and then for all the models with a UKA in the different alignment configurations by using the average contact pressure. The average percentages of the load are shown in Figure 3.
The transferred load (in N) in the lateral and medial compartments for all of the analyzed knee models is reported in Table 2. In particular, it is possible to notice the load distribution
Discussion
This study aimed at analyzing, until now uncovered topic, about the optimal tibial alignment for UKA and potential aberrant performances due to malpositioning of the components. To investigate this question, a FE model was used to analyze and compare different configurations for several biomechanical outputs.
This numerical study comes with several assumptions, that is, only 1 patient's anatomy has been considered and only 1 UKA design has been virtually implanted. Additionally, potential
Conclusion
Neutral tibial alignment or a slight varus alignment (3°) in the coronal plane can effectively extend the life expectancy of a UKA being also compatible with soft tissue strains. Overcorrections could lead to higher stresses in the lateral compartment and to stress shielding under the implant.
Acknowledgments
This work was supported by FNRS (Fonds National de la Recherche Scientifique, CDR 19545501) and by FER ULB (Fonds d'Encouragement à la Recherche, FER 2014). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
References (43)
- et al.
Rapid recovery after Oxford unicompartmental arthroplasty through a short incision
J Arthroplasty
(2001) - et al.
Factors influencing walking and stairclimbing following unicompartmental knee arthroplasty
J Arthroplasty
(1986) - et al.
Unicompartmental knee arthroplasty surgery. 10-year minimum follow-up period
J Arthroplasty
(1996) - et al.
Biomechanical evaluation of proximal tibial behaviour following unicondylar knee arthroplasty: modified resected surface with corresponding surgical technique
Med Eng Phys
(2011) - et al.
Contact forces in several TKA designs during squatting: a numerical sensitivity analysis
J Biomech
(2011) - et al.
Tibio-femoral kinematics in different total knee arthroplasty designs during a loaded squat: a numerical sensitivity study
J Biomech
(2012) - et al.
The effects of static, dynamic and fatigue behavior on three-dimensional shape optimization of hip prosthesis by finite element method
Mater Des
(2007) - et al.
Load sharing and ligament strains in balanced, overstuffed and understuffed UKA. A validated finite element analysis
J Arthroplasty
(2014) - et al.
A three-dimensional finite element analysis of the combined behavior of ligaments and menisci in the healthy human knee joint
J Biomech
(2006) - et al.
Ultra high molecular weight polyethylene: mechanics, morphology, and clinical behavior
J Mech Behav Biomed Mater
(2009)
A three-dimensional finite element stress analysis for tunnel placement and buttons in anterior cruciate ligament reconstructions
J Biomech
Biomechanics of the human knee joint in compression: reconstruction, mesh generation and finite element analysis
Knee
The mechanics of the knee joint in relation to normal walking
J Biomech
Epiphyseal-based designs for tibial plateau components—ii. stress analysis in the sagittal plane
J Biomech
The precision and accuracy of templating the size of unicondylar knee arthroplasty
Knee
Finite element analysis of the implanted proximal tibia: a relationship between the initial cancellous bone stresses and implant migration
J Biomech
Impact of osteoarthritis on individuals and society: how much disability? Social consequences and health economic implications
Curr Opin Rheumatol
The prevalence and burden of arthritis
Rheumatology
Knee biomechanics after UKA and its relation to the ACL— a robotic investigation
J Orthop Res
Unicompartmental knee arthroplasty. Clinical experience at 6- to 10-year followup
Clin Orthop Relat Res
Unicondylar knee arthroplasty
J Bone Joint Surg Am
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One or more of the authors of this paper have disclosed potential or pertinent conflicts of interest, which may include receipt of payment, either direct or indirect, institutional support, or association with an entity in the biomedical field which may be perceived to have potential conflict of interest with this work. For full disclosure statements refer to http://dx.doi.org/10.1016/j.arth.2016.07.006.