Wearable Motion Capture System Evaluation for Biomechanical Studies for Hip Joints

2020 ◽  
Author(s):  
Senay Mihcin ◽  
Samet Ciklacandir ◽  
Mertcan Kocak ◽  
Aliye Tosun
Keyword(s):  
Motion Capture ◽  
Hip Joint ◽  
External Rotation ◽  
Human Motion ◽  
Simulation Software ◽  
Wearable System ◽  
Single Plane ◽  
Flexion Extension

Abstract Human motion capture (MOCAP) systems are vital, while determining the loads occurring at the joints. Most of the clinical MOCAP systems are very costly, requiring investment and infrastructure. Therefore, alternative technologies are in demand. In this study, a novel marker-less wearable MOCAP system, was assessed for its compatibility with a biomechanical modelling software. To collect evidence, experiments were designed in two stages for quantifying the range of motion of the hip joint; in vitro and in vivo. Three constrained-single-plane motions; abduction/adduction, flexion/extension, and internal/external rotation movements of the active leg were analysed. The data were collected from 14 healthy volunteers, using the wearable system and a medical grade optoelectronic MOCAP system simultaneously and compared against. For the in vitro study, the Root Mean Square Error (RMSE) for the abduction/adduction motion of the hip joint was calculated as 0.11°/0.30° and 0.11°/0.09° respectively for the wearable and the opto-electronic system. The in vivo Bland-Altman plots showed that the two system data are comparable. The simulation software is found compatible to run the simulations in offline mode. The wearable system could be utilized in the field of biomechanics software for running the kinetic simulations. The results demonstrated that the wearable system could be an alternative in the field of biomechanics based on the evidence collected.

A physiologically based biopharmaceutical analysis of zolpidem

2021 ◽  
Author(s):  
◽  
Rafael Leal Monteiro Paraiso
Keyword(s):  
Drug Development ◽  
Drug Absorption ◽  
Oral Absorption ◽  
Food Effect ◽  
Simulation Software ◽  
Oral Drug ◽  
Oral Drug Absorption ◽  
Physiologically Based

Computational oral absorption models, in particular PBBM models, provide a powerful tool for researchers and pharmaceutical scientists in drug discovery and formulation development, as they mimic and can describe the physiologically processes relevant to the oral absorption. PBBM models provide in vivo context to in vitro data experiments and allow for a dynamic understanding of in vivo drug disposition that is not typically provided by data from standard in vitro assays. Investigations using these models permit informed decision-making, especially regarding to formulation strategies in drug development. PBBM models, but can also be used to investigate and provide insight into mechanisms responsible for complex phenomena such as food effect in drug absorption. Although there are obviously still some gaps regarding the in silico construction of the gastrointestinal environment, ongoing research in the area of oral drug absorption (e.g. the UNGAP, AGE-POP and InPharma projects) will increase knowledge and enable improvement of these models. PBBM can nowadays provide an alternative approach to the development of in vitro–in vivo correlations. The case studies presented in this thesis demonstrate how PBBM can address a mechanistic understanding of the negative food effect and be used to set clinically relevant dissolution specification for zolpidem immediate release tablets. In both cases, we demonstrated the importance of integrating drug properties with physiological variables to mechanistically understand and observe the impact of these parameters on oral drug absorption. Various complex physiological processes are initiated upon food consumption, which can enhance or reduce a drug’s dissolution, solubility, and permeability and thus lead to changes in drug absorption. With improvements in modeling and simulation software and design of in vitro studies, PBBM modeling of food effects may eventually serve as a surrogate for clinical food effect studies for new doses and formulations or drugs. Furthermore, the application of these models may be even more critical in case of compounds where execution of clinical studies in healthy volunteers would be difficult (e.g., oncology drugs). In the fourth chapter we have demonstrated the establishment of the link between biopredictive in vitro dissolution testing (QC or biorelevant method) PBBM coupled with PD modeling opens the opportunity to set truly clinically relevant specifications for drug release. This approach can be extended to other drugs regardless of its classification according to the BCS. With the increased adoption of PBBM, we expect that best practices in development and verification of these models will be established that can eventually inform a regulatory guidance. Therefore, the application of Physiologically Based Biopharmaceutical Modelling is an area with great potential to streamline late-stage drug development and impact on regulatory approval procedures. Freie Schlagwörter / Tags

scholarly journals Can the Open Stance Forehand Increase the Risk of Hip Injuries in Tennis Players?

2020 ◽  
Vol 8 (12) ◽  
pp. 232596712096629
Author(s):  
Caroline Martin ◽  
Anthony Sorel ◽  
Pierre Touzard ◽  
Benoit Bideau ◽  
Ronan Gaborit ◽  
...  
Keyword(s):  
Hip Joint ◽  
Inverse Dynamics ◽  
External Rotation ◽  
Tennis Players ◽  
Flexion Extension ◽  
Hip Injuries ◽  
Hip Motion ◽  
Hip Kinematics ◽  
The Right ◽  
Hip Flexion

Background: The open stance forehand has been hypothesized by tennis experts (coaches, scientists, and clinicians) to be more traumatic than the neutral stance forehand as regards hip injuries in tennis. However, the influence of the forehand stance (open or neutral) on hip kinematics and loading has not been assessed. Purpose: To compare the kinematics and kinetics at the hip joint during 3 common forehand stances (attacking neutral stance [ANS], attacking open stance [AOS], defensive open stance [DOS]) in advanced tennis players to determine whether the open stance forehand induces higher hip loading. Study Design: Descriptive laboratory study. Methods: The ANS, AOS, and DOS forehand strokes of 8 advanced right-handed tennis players were recorded with an optoelectronic motion capture system. The flexion-extension, abduction-adduction, and external-internal rotation angles as well as intersegmental forces and torques of the right hip were calculated using inverse dynamics. Results: The DOS demonstrated significantly higher values than both the ANS and AOS for anterior ( P < .001), medial ( P < .001), and distractive ( P < .001) forces as well as extension ( P = .004), abduction ( P < .001), and external rotation ( P < .001) torques. The AOS showed higher distractive forces than the ANS ( P = .048). The DOS showed more extreme angles of hip flexion ( P < .001), abduction ( P < .001), and external rotation ( P = .010). Conclusion: The findings of this study imply that the DOS increased hip joint angles and loading, thus potentially increasing the risk of hip overuse injuries. The DOS-induced hip motion could put players at a higher risk of posterior-superior hip impingement compared with the ANS and AOS. Clinical Relevance: Coaches and clinicians with players who have experienced hip pain or sustained injuries should encourage them to use a more neutral stance and develop a more aggressive playing style to avoid the DOS, during which hip motion and loading are more extreme.

Evaluation of the relationship of tibiofemoral kinematics before and after total knee replacement in an in vitro model of cranial cruciate deficiency in the dog

2016 ◽  
Vol 29 (06) ◽  
pp. 484-490 ◽  
Author(s):  
Rebecca Howie ◽  
Timothy Foutz ◽  
Curtis Cathcart ◽  
Jeff Burmeister ◽  
Steve Budsberg
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
External Rotation ◽  
Cruciate Ligament ◽  
Flexion Extension ◽  
Before And After ◽  
Total Knee ◽  
Tibiofemoral Kinematics ◽  
The Relationship

SummaryObjective: To investigate the relationship between tibiofemoral kinematics before and after total knee replacement (TKR) in vitro.Animals: Eight canine hemipelves.Methods: A modified Oxford Knee Rig was used to place cadaveric limbs through a range of passive motion allowing the kinematics of the stifle to be evaluated. Four measurements were performed: a control stage, followed by a cranial cruciate transection stage, then following TKR with the musculature intact stage, and finally TKR with removal of limb musculature stage. Joint angles and translations of the femur relative to the tibia, including flexion-extension versus adduction-abduction, flexion-extension versus internal-external rotation, as well as flexion-extension versus each translation (cranial-caudal and lateral-medial) were calculated.Results: Significant differences were identified in kinematic data from limbs following TKR implantation as compared to the unaltered stifle. The TKR resulted in significant decreases in external rotation of the stifle during flexion-extension compared to the limb prior to any intervention, as well as increasing the abduction. The TKR significantly increased the caudal translation of the femur relative to the tibia compared to the unaltered limb. When compared with the cranial cruciate ligament-transection stage, TKR significantly decreased the ratio of the external rotation to flexion.Discussion: All three test periods showed significant differences from the unaltered stifle. The TKR did not completely restore the normal kinematics of the stifle.

The clinical relevance of hip joint simulator testing: In vitro and in vivo comparisons

Wear ◽  
2005 ◽  
Vol 259 (7-12) ◽  
pp. 882-886 ◽  
Author(s):  
Aaron Essner ◽  
Gregg Schmidig ◽  
Aiguo Wang
Keyword(s):  
Hip Joint ◽  
Clinical Relevance ◽  
Hip Joint Simulator

Measuring Dynamic In-Vivo Elbow Kinematics: Description of Technique and Estimation of Accuracy

2012 ◽  
Vol 134 (12) ◽  
Author(s):  
Colin P. McDonald ◽  
Vasilios Moutzouros ◽  
Michael J. Bey
Keyword(s):  
Full Extension ◽  
X Ray ◽  
Tracking Technique ◽  
Model Based ◽  
Flexion Extension ◽  
Full Flexion ◽  
Position And Orientation ◽  
Elbow Motion

Background: The objectives of this study were to characterize the translational and rotational accuracy of a model-based tracking technique for quantifying elbow kinematics and to demonstrate its in vivo application. Method of Approach: The accuracy of a model-based tracking technique for quantifying elbow kinematics was determined in an in vitro experiment. Biplane X-ray images of a cadaveric elbow were acquired as it was manually moved through flexion-extension. The 3D position and orientation of each bone was determined using model-based tracking. For comparison, the position and orientation of each bone was also determined by tracking the position of implanted beads with dynamic radiostereometric analysis. Translations and rotations were calculated for both the ulnohumeral and radiohumeral joints, and compared between measurement techniques. To demonstrate the in vivo application of this technique, biplane X-ray images were acquired as a human subject extended their elbow from full flexion to full extension. Results: The in vitro validation demonstrated that the model-based tracking technique is capable of accurately measuring elbow motion, with reported errors averaging less than ±1.0 mm and ±1.0 deg. For the in vivo application, the carrying angle changed from an 8.3 ± 0.5 deg varus position in full flexion to an 8.4 ± 0.5 deg valgus position in full extension. Conclusions: Model-based tracking is an accurate technique for measuring in vivo, 3D, dynamic elbow motion. It is anticipated that this experimental approach will enhance our understanding of elbow motion under normal and pathologic conditions.

scholarly journals Patient-specific resurfacing implant knee surgery in subjects with early osteoarthritis results in medial pivot and lateral femoral rollback during flexion: a retrospective pilot study

2021 ◽  
Author(s):  
Philippe Moewis ◽  
René Kaiser ◽  
Adam Trepczynski ◽  
Christoph von Tycowicz ◽  
Leonie Krahl ◽  
...  
Keyword(s):  
Knee Arthroplasty ◽  
External Rotation ◽  
Knee Kinematics ◽  
Axial Rotation ◽  
Patient Specific ◽  
Post Surgery ◽  
Flexion Extension ◽  
Medial Pivot ◽  
Femoral Rollback

Abstract Purpose Metallic resurfacing implants have been developed for the treatment of early, small, condylar and trochlear osteoarthritis (OA) lesions. They represent an option for patients who do not fulfill the criteria for unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA) or are too old for biological treatment. Although clinical evidence has been collected for different resurfacing types, the in vivo post-operative knee kinematics remain unknown. The present study aims to analyze the knee kinematics in subjects with patient-specific episealer implants. This study hypothesized that patient-specific resurfacing implants would lead to knee kinematics close to healthy knees, resulting in medial pivot and a high degree of femoral rollback during flexion. Methods Retrospective study design. Fluoroscopic analysis during unloaded flexion–extension and loaded lunge was conducted at > 12 months post-surgery in ten episealer knees, and compared to ten healthy knees. Pre- and post-operative clinical data of the episealer knees were collected using a visual analog scale (VAS), the EQ 5d Health, and the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaires. Results A consistent medial pivot was observed in both episealer and healthy knees. Non-significant differences were found in the unloaded (p = 0.15) and loaded (p = 0.51) activities. Although lateral rollback was observed in both groups, it was significantly higher for the episealer knees in both the unloaded (p = 0.02) and loaded (p = 0.01) activities. Coupled axial rotation was significantly higher in the unloaded (p = 0.001) but not in the loaded (p = 0.06) activity in the episealer knees. Improved scores were observed at 1-year post-surgery in the episealer subjects for the VAS (p = 0.001), KOOS (p = 0.001) and EQ Health (p = 0.004). Conclusion At 12 month follow-up, a clear physiological knee kinematics pattern of medial pivot, lateral femoral rollback and coupled axial external femoral rotation during flexion was observed in patients treated with an episealer resurfacing procedure. However, higher femoral rollback and axial external rotation in comparison to healthy knees was observed, suggesting possible post-operative muscle weakness and consequent insufficient stabilization at high flexion.

scholarly journals Evaluation of in vitro dissolution similarity of bisoprolol film-coated tablets based on Weibull modelling using MATLABTM simulation software

2021 ◽  
Vol 10 (1) ◽  
pp. 056-073
Author(s):  
Ivana Mitrevska ◽  
Hristijan Mickoski ◽  
Katerina Brezovska ◽  
Aneta Dimitrovska
Keyword(s):  
Immediate Release ◽  
Simulation Software ◽  
In Vitro Dissolution ◽  
Accurate Estimation ◽  
Mathematical Function ◽  
Medicinal Products ◽  
Non Linear ◽  
Linear Effects

The aim of this study was to compare the in vitro dissolution behaviour of reference (R) and generic-test (T) medicinal products with non-linear effects model. Mathematical function Weibull, was employed as basis for the non-linear effects model, coupled with MATLABTM simulation software to describe the release profile of the active substance. Medicinal products selected for the presented study include immediate-release tablets Concor 10 mg and Bisoprolol 10 mg, which belongs to BCS class 1 of biopharmaceutics classification system. The result from the study indicated that Weibull distribution function coupled with computer-based program is more useful for comparison of the dissolution profiles. This combined approach provides robust and informative results, with accurate estimation on the in vitro performance for the medicinal products and it’s the most suitable tool for prediction of in vivo behaviour of the medicinal product. In summary, we have employed Simulink graphical programming to design our system in a simulation environment.

scholarly journals Evaluation of RSA set-up from a clinical biplane fluoroscopy system for 3D joint kinematic analysis

Joints ◽  
2016 ◽  
Vol 04 (02) ◽  
pp. 121-125 ◽  
Author(s):  
Tommaso Bonanzinga ◽  
Cecilia Signorelli ◽  
Marco Bontempi ◽  
Alessandro Russo ◽  
Stefano Zaffagnini ◽  
...  
Keyword(s):  
Rigid Body ◽  
Kinematic Analysis ◽  
In Vitro Test ◽  
Flexion Extension ◽  
Vitro Test ◽  
Set Up ◽  
Static Conditions ◽  
Biplane Fluoroscopy

Purpose: dinamic roentgen stereophotogrammetric analysis (RSA), a technique currently based only on customized radiographic equipment, has been shown to be a very accurate method for detecting threedimensional (3D) joint motion. The aim of the present work was to evaluate the applicability of an innovative RSA set-up for in vivo knee kinematic analysis, using a biplane fluoroscopic image system. To this end, the Authors describe the set-up as well as a possible protocol for clinical knee joint evaluation. The accuracy of the kinematic measurements is assessed. Methods: the Authors evaluated the accuracy of 3D kinematic analysis of the knee in a new RSA set-up, based on a commercial biplane fluoroscopy system integrated into the clinical environment. The study was organized in three main phases: an in vitro test under static conditions, an in vitro test under dynamic conditions reproducing a flexion-extension range of motion (ROM), and an in vivo analysis of the flexionextension ROM. For each test, the following were calculated, as an indication of the tracking accuracy: mean, minimum, maximum values and standard deviation of the error of rigid body fitting. Results: in terms of rigid body fitting, in vivo test errors were found to be 0.10±0.05 mm. Phantom tests in static and kinematic conditions showed precision levels, for translations and rotations, of below 0.1 mm/0.2º and below 0.5 mm/0.3º respectively for all directions. Conclusions: the results of this study suggest that kinematic RSA can be successfully performed using a standard clinical biplane fluoroscopy system for the acquisition of slow movements of the lower limb. Clinical relevance: a kinematic RSA set-up using a clinical biplane fluoroscopy system is potentially applicable and provides a useful method for obtaining better characterization of joint biomechanics.

scholarly journals Experimental evaluation of precision and accuracy of RSA in the lumbar spine

2020 ◽  
Author(s):  
Marie Christina Keller ◽  
Christof Hurschler ◽  
Michael Schwarze
Keyword(s):  
Lumbar Spine ◽  
Focal Spot ◽  
Lateral Bending ◽  
Flexion Extension ◽  
Hip And Knee Arthroplasty ◽  
Spinal Region ◽  
Precision And Accuracy ◽  
Bone Structures

Abstract Purpose Roentgen stereophotogrammetric analysis is a technique to make accurate assessments of the relative position and orientation of bone structures and implants in vivo. While the precision and accuracy of stereophotogrammetry for hip and knee arthroplasty is well documented, there is insufficient knowledge of the technique’s precision and, especially accuracy when applied to rotational movements in the spinal region. Methods The motion of one cadaver lumbar spine segment (L3/L4) was analyzed in flexion–extension, lateral bending and internal rotation. The specific aim of this study was to examine the precision and accuracy of stereophotogrammetry in a controlled in vitro setting, taking the surrounding soft tissue into account. The second objective of this study was to investigate the effect of different focal spot values of X-ray tubes. Results Overall, the precision of flexion–extension measurements was found to be better when using a 0.6 mm focal spot value rather than 1.2 mm (± 0.056° and ± 0.153°; respectively), and accuracy was also slightly better for the 0.6 mm focal spot value compared to 1.2 mm (− 0.137° and − 0.170°; respectively). The best values for precision and accuracy were obtained in lateral bending for both 0.6 mm and 1.2 mm focal spot values (precision: ± 0.019° and ± 0.015°, respectively; accuracy: − 0.041° and − 0.035°). Conclusion In summary, the results suggest stereophotogrammetry to be a highly precise method to analyze motion of the lumbar spine. Since precision and accuracy are better than 0.2° for both focal spot values, the choice between these is of minor clinical relevance.

The influence of shape and sliding distance of femoral head movement loci on the wear of acetabular cups in total hip arthroplasty

2002 ◽  
Vol 216 (6) ◽  
pp. 393-402 ◽  
Author(s):  
D Bennett ◽  
J F Orr ◽  
D E Beverland ◽  
R Baker
Keyword(s):  
Femoral Head ◽  
Aspect Ratio ◽  
Hip Joint ◽  
Wear Rates ◽  
Total Hip ◽  
Aspect Ratios ◽  
Average Aspect Ratio ◽  
Sliding Distance

Wear of the polyethylene acetabular component is the most serious threat to the long-term success of total hip replacements (THRs). Greatly reduced wear rates have been reported for unidirectional, compared to multidirectional, articulation in vitro. This study considers the multidirectional motions experienced at the hip joint as described by movement loci of points on the femoral head for individual THR patients. A three-dimensional computer program determined the movement loci of selected points on the femoral head for THR patients and normal subjects using kinematic data obtained from gait analysis. The sizes and shapes of these loci were quantified by their sliding distances and aspect ratios with substantial differences exhibited between individual THR patients. The average sliding distances ranged from 10.0 to 18.1 mm and the average aspect ratios of the loci ranged from 2.5 to 9.2 for the THR patients. Positive correlations were found between wear rate and average sliding distance, the inverse of the average aspect ratio of the loci and the product of the average sliding distance and the inverse of the average aspect ratio of the loci. Patients with a normal hip joint range of motion produce multidirectional motion loci and tend to experience more wear than patients with more unidirectional motion loci. Differing patterns of multidirectional motion at the hip joint for individual THR patients may explain widely differing wear rates in vivo.

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