A 3D Motion Phantom for Assessing the Accuracy and Precision of Dynamic Magnetic Resonance Measurement of In Vivo Knee Kinematics

2013 ◽  
Author(s):  
Jarred Kaiser ◽  
Rajeev Chaudhary ◽  
Oliver Wieben ◽  
Richard Kijowski ◽  
Darryl Thelen
Keyword(s):  
Magnetic Resonance ◽  
Knee Kinematics ◽  
Dynamic Mri ◽  
Accuracy And Precision ◽  
Volumetric Models ◽  
Motion Phantom ◽  
Skeletal Kinematics ◽  
Tibiofemoral Kinematics ◽  
In Vivo Knee Kinematics

Measurement of in vivo knee kinematics can provide useful insight into disease, injury, and clinical treatment. Cartilage loading patterns are of particular interest while studying the progression of osteoarthritis [1]. However, inferring cartilage contact from skeletal kinematics requires high resolution volumetric models of cartilage surfaces and accurate skeletal positions and orientations. This is a challenging requirement at the knee, which exhibits substantial translation and non-sagittal rotation during normal activities such as gait [2]. We have recently introduced a novel 3D cine magnetic resonance (MR) imaging technique to measure in vivo tibiofemoral kinematics [3]. The purpose of this study was to develop a MR-compatible motion phantom that can generate repeatable 3D skeletal motion suitable for quantifying the accuracy and precision of kinematics derived from dynamic MRI.

scholarly journals Subject-Specific Finite Element Modeling of the Tibiofemoral Joint Based on CT, Magnetic Resonance Imaging and Dynamic Stereo-Radiography Data in Vivo

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Robert E. Carey ◽  
Liying Zheng ◽  
Ameet K. Aiyangar ◽  
Christopher D. Harner ◽  
Xudong Zhang
Keyword(s):  
Magnetic Resonance Imaging ◽  
Finite Element ◽  
Magnetic Resonance ◽  
Contact Area ◽  
Resonance Imaging ◽  
Model Predictions ◽  
Subject Specific ◽  
Skeletal Kinematics ◽  
Tibiofemoral Kinematics

In this paper, we present a new methodology for subject-specific finite element modeling of the tibiofemoral joint based on in vivo computed tomography (CT), magnetic resonance imaging (MRI), and dynamic stereo-radiography (DSX) data. We implemented and compared two techniques to incorporate in vivo skeletal kinematics as boundary conditions: one used MRI-measured tibiofemoral kinematics in a nonweight-bearing supine position and allowed five degrees of freedom (excluding flexion-extension) at the joint in response to an axially applied force; the other used DSX-measured tibiofemoral kinematics in a weight-bearing standing position and permitted only axial translation in response to the same force. Verification and comparison of the model predictions employed data from a meniscus transplantation study subject with a meniscectomized and an intact knee. The model-predicted cartilage-cartilage contact areas were examined against “benchmarks” from a novel in situ contact area analysis (ISCAA) in which the intersection volume between nondeformed femoral and tibial cartilage was characterized to determine the contact. The results showed that the DSX-based model predicted contact areas in close alignment with the benchmarks, and outperformed the MRI-based model: the contact centroid predicted by the former was on average 85% closer to the benchmark location. The DSX-based FE model predictions also indicated that the (lateral) meniscectomy increased the contact area in the lateral compartment and increased the maximum contact pressure and maximum compressive stress in both compartments. We discuss the importance of accurate, task-specific skeletal kinematics in subject-specific FE modeling, along with the effects of simplifying assumptions and limitations.

Does the Modified Arrhenius Model Reliably Predict Area of Tissue Ablation After Magnetic Resonance-Guided Laser Interstitial Thermal Therapy for Pediatric Lesional Epilepsy?

2021 ◽  
Author(s):  
Kelsey D Cobourn ◽  
Imazul Qadir ◽  
Islam Fayed ◽  
Hepzibha Alexander ◽  
Chima O Oluigbo
Keyword(s):  
Magnetic Resonance ◽  
Linear Regression ◽  
Magnetic Resonance Images ◽  
Thermal Therapy ◽  
Invasive Technique ◽  
Hypothalamic Hamartoma ◽  
Arrhenius Model ◽  
Laser Interstitial Thermal Therapy ◽  
Accuracy And Precision

Abstract BACKGROUND Commercial magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) systems utilize a generalized Arrhenius model to estimate the area of tissue damage based on the power and time of ablation. However, the reliability of these estimates in Vivo remains unclear. OBJECTIVE To determine the accuracy and precision of the thermal damage estimate (TDE) calculated by commercially available MRgLITT systems using the generalized Arrhenius model. METHODS A single-center retrospective review of pediatric patients undergoing MRgLITT for lesional epilepsy was performed. The area of each lesion was measured on both TDE and intraoperative postablation, postcontrast T1 magnetic resonance images using ImageJ. Lesions requiring multiple ablations were excluded. The strength of the correlation between TDE and postlesioning measurements was assessed via linear regression. RESULTS A total of 32 lesions were identified in 19 patients. After exclusion, 13 pairs were available for analysis. Linear regression demonstrated a strong correlation between estimated and actual ablation areas (R2 = .97, P < .00001). The TDE underestimated the area of ablation by an average of 3.92% overall (standard error (SE) = 4.57%), but this varied depending on the type of pathologic tissue involved. TDE accuracy and precision were highest in tubers (n = 3), with average underestimation of 2.33% (SE = 0.33%). TDE underestimated the lesioning of the single hypothalamic hamartoma in our series by 52%. In periventricular nodular heterotopias, TDE overestimated ablation areas by an average of 13% (n = 2). CONCLUSION TDE reliability is variably consistent across tissue types, particularly in smaller or periventricular lesions. Further investigation is needed to understand the accuracy of this emerging minimally invasive technique.

scholarly journals In vivo knee kinematics during high flexion after a posterior-substituting total knee arthroplasty

2009 ◽  
Vol 34 (4) ◽  
pp. 497-503 ◽  
Author(s):  
Angela L. Moynihan ◽  
Kartik M. Varadarajan ◽  
George R. Hanson ◽  
Sang-Eun Park ◽  
Kyung Wook Nha ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Knee Kinematics ◽  
High Flexion ◽  
Total Knee ◽  
In Vivo Knee Kinematics

scholarly journals Which one restores in vivo knee kinematics effectively-medial or lateral pivot?

2020 ◽  
Author(s):  
Sahil Batra ◽  
Pon Aravindhan A. Sugumar ◽  
Vijay Kumar ◽  
Rajesh Malhotra
Keyword(s):  
Knee Kinematics ◽  
In Vivo Knee Kinematics

The Effect of Joint Line Elevation on In Vivo Knee Kinematics in Bicruciate Retaining Total Knee Arthroplasty

2021 ◽  
Author(s):  
Christian Klemt ◽  
Anand Padmanabha ◽  
Venkatsaiakhil Tirumala ◽  
Evan J. Smith ◽  
Young-Min Kwon
Keyword(s):  
Negative Correlation ◽  
Knee Kinematics ◽  
Significant Negative Correlation ◽  
Significant Loss ◽  
Maximum Flexion ◽  
Sit To Stand ◽  
Total Knee ◽  
In Vivo Knee Kinematics ◽  
Bcr Tka

AbstractPrior studies have reported a negative effect on both clinical outcomes and patient-reported outcome measures (PROMS) following joint line elevation (JLE) in cruciate-retaining (CR) total knee arthroplasty (TKA) and posterior stabilized (PS) TKA designs. This experimental study was aimed to quantify the effect of JLE on in vivo knee kinematics in patients with bicruciate retaining (BCR) TKA during strenuous activities. Thirty unilateral BCR TKA patients were evaluated during single-leg deep lunge and sit-to-stand using a validated combined computer tomography and dual fluoroscopic imaging system. Correlation analysis was performed to quantify any correlations between JLE and in vivo kinematics, as well as PROMS. There was a significant negative correlation between JLE and maximum flexion angle during single-leg deep lunge (ρ = −0.34, p = 0.02), maximum varus joint angles during single-leg deep lunge (ρ = −0.37, p = 0.04), and sit-to-stand (ρ = −0.29, p = 0.05). There was a significant negative correlation between JLE and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (ρ = −0.39, p = 0.01) and knee disability and osteoarthritis outcome score physical function (KOOS-PS; ρ = −0.33, p = 0.03). The JLE that yields a significant loss in PROMS and maximum flexion angles were 2.6 and 2.3 mm, respectively. There was a linear negative correlation of JLE with both in vivo knee kinematics and PROMS, with changes in JLE of greater than 2.6 and 2.3 mm, leading to a clinically significant loss in PROMS and maximum flexion angles, respectively, suggesting an increased need to improve surgical precision to optimize patient outcomes following BCR TKA.

Sign in / Sign up

Export Citation Format

Share Document