scholarly journals Alterations in Three-dimensional Knee Kinematics and Kinetics during Neutral, Squeeze and Outward Squat

2013 ◽  
Vol 39 (1) ◽  
pp. 59-66 ◽  
Author(s):  
Shuyang Han ◽  
Shirong Ge ◽  
Hongtao Liu ◽  
Rong Liu
Keyword(s):  
Three Dimensional ◽  
Knee Kinematics ◽  
Neutral Position ◽  
Joint Forces ◽  
Peak Knee ◽  
Significant Difference ◽  
Squat Exercise ◽  
Reaction Forces ◽  
Different Populations ◽  
Compare And Contrast

Abstract The squat exercise was usually performed with varying feet and hip angles by different populations. The objective of this study was to compare and contrast the three-dimensional knee angles, moments, and forces during dynamic squat exercises with varying feet and hip angles. Lower extremity motions and ground reaction forces for fifteen healthy subjects (9 females and 6 males) were recorded while performing the squat with feet pointing straight ahead (neutral squat), 30º feet adduction (squeeze squat) and 30º feet abduction (outward squat). Nonparametric procedures were used to detect differences in the interested measures between the conditions. No significant difference in three-dimensional peak knee angles was observed for three squat exercises (p>0.05), however, the overall tendency of knee rotations was affected by varying feet and hip positions. During the whole cycle, the outward squat mainly displayed adduction moments, while the neutral and squeeze squat demonstrated abduction moments. Peak abduction moments were significantly affected by feet positions (p<0.05). Moreover, the tibiofemoral and patellofemoral joint forces progressively increased as knee flexed and decreased as knee extended, yet peak forces were not affected by varying feet positions (p>0.05). In conclusion, a neutral position is recommended to perform the squat exercise, while the squeeze squat and outward squat might contribute to the occurrence of joint pathologies.

Age-Dependent Three-Dimensional Evaluation of the Spheno-Occipital Synchondrosis Using Computed Tomography

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Arezoo Jahanbin ◽  
Shirin Dokht Shirazi ◽  
Elaheh Kamyabnezhad ◽  
Neda Eslami ◽  
Seyed Hosein Hoseini Zarch
Keyword(s):  
Developmental Stage ◽  
Three Dimensional ◽  
Cross Sectional ◽  
Old Patients ◽  
Significant Difference ◽  
Growth Center ◽  
Different Populations ◽  
Males And Females ◽  
Ossification Process ◽  
Age And Sex

Background: The spheno‐occipital synchondrosis (SOS) is an important growth center which plays an important role in cranial base development and can define the final relation of SOS with the upper and lower jaws. The morphology and fusion degree of SOS varies in different ages among different populations. Objectives: Thus, the aim of this study was to evaluate the age and sex dependence of ossification of the spheno-occipital synchondrosis in the Iranian population using CBCT. Methods: This cross-sectional retrospective study was performed on 517 CBCT images of 6- to 18-year-old patients in Mashhad, Iran. Patients with obvious pathology or fractures were excluded from the study. The SOS ossification was classified into four stages from 0 to 3. Two independent observers scored the images. The ossification stage of the SOS was classified according to the age and sex of the patients. Kruskal-Wallis and Kendall’s tau-b used for statistical analysis. Results: In this study, 517 samples of 260 females (50.3%) and 257 males (49.7%) with a mean age of 12.03 ± 3.74 years were examined. A significant difference did not exist between males and females regarding their stage of SOS ossification, although males were younger at the SOS transitional stages of 0 to 1, and 1 to 2 compared to females. Also, the SOS starts the ossification process at the age of 11 in females and 10.8 in males. Conclusions: The present study showed in the mean age of 16.81 ± 1.12 years, most subjects were in developmental stage 3. Due to the fact that in developmental stage 3 SOS closes, there were no passive maxillary growth after this time. In none of the SOS stages, females and males differed significantly in mean age (P > 0.05). The age of the onset of SOS closure in females was 11 years and in males it was about 10.8 years.

Influence of Modern Studded and Bladed Soccer Boots and Sidestep Cutting on Knee Loading during Match Play Conditions

2007 ◽  
Vol 35 (9) ◽  
pp. 1528-1536 ◽  
Author(s):  
Rajiv Kaila
Keyword(s):  
Inverse Dynamics ◽  
Cruciate Ligament ◽  
Three Dimensional ◽  
Match Play ◽  
Joint Forces ◽  
Significant Difference ◽  
Knee Loading ◽  
Anterior Cruciate ◽  
Inverse Dynamics Analysis ◽  
Straight Ahead

Background The influence of modern studded and bladed soccer boots and sidestep cutting on noncontact knee loading during match play conditions is not fully understood. Hypothesis Modern soccer boot type and sidestep cutting compared with straight-ahead running do not significantly influence knee internal tibia axial and valgus moments, anterior joint forces, and flexion angles. Study Design Controlled laboratory study. Methods Fifteen professional male outfield soccer players undertook trials of straight-ahead running and sidestep cutting at 30° and 60° with a controlled approach velocity on a Fédération Internationale de Football Association (FIFA) approved soccer surface. Two bladed and 2 studded soccer boots from 2 manufacturers were investigated. Three-dimensional inverse dynamics analysis determined externally applied internal/external tibia axial and valgus/varus moments, anterior forces, and flexion angles throughout stance. Results The soccer boot type imparted no significant difference on knee loading for each maneuver. Internal tibia and valgus moments were significantly greater for sidestep cutting at 30° and 60° compared with straight-ahead running. Sidestep cutting at 60° compared with straight-ahead running significantly increased anterior joint forces. Conclusion Varying soccer boot type had no effect on knee loading for each maneuver, but sidestep cutting significantly increased internal tibia and valgus moments and anterior joint forces. Clinical Relevance Sidestep cutting, irrespective of the modern soccer boot type worn, may be implicated in the high incidence of noncontact soccer anterior cruciate ligament injuries by significantly altering knee loading.

Hip Taping Positively Alters Running Kinematics in Asymptomatic Females

2018 ◽  
Vol 39 (14) ◽  
pp. 1068-1074
Author(s):  
Ashleigh Masters ◽  
Kevin Netto ◽  
Susi Brooker ◽  
Diana Hopper ◽  
Bernard Liew
Keyword(s):  
Internal Rotation ◽  
Stance Phase ◽  
Three Dimensional ◽  
Statistical Parametric Mapping ◽  
Knee Kinematics ◽  
Knee Valgus ◽  
Peak Knee ◽  
Running Injuries ◽  
Hip Motion ◽  
Post Hoc

AbstractGreater functional knee valgus (FKV) is thought to contribute to a greater risk of sustaining overuse running injuries. The hip is commonly implicated in greater functional knee valgus, but no studies have investigated the effects of hip taping on running kinematics. The present study investigated whether or not hip taping altered hip and knee kinematics compared to sham and no taping in female runners demonstrating excessive functional knee valgus. Lower limb stance-phase kinematics were collected from 23 female runners using three-dimensional motion capture. Participants performed over ground running at 3.5 m/s and 5.0 m/s. Three taping conditions (no tape; sham tape; hip tape) were tested. Statistical inference was performed using Statistical Parametric Mapping Hotelling’s paired t-tests, with post-hoc paired t-tests. Hip taping significantly decreased hip adduction and internal rotation angles throughout stance phase by up to 7°, compared to sham and no taping. Hip taping significantly increased knee adduction, internal rotation, flexion, and reduced peak knee flexion angles, compared to no tape. Hip taping reduced excessive hip motion by clinically meaningful magnitudes, and also benefited knee frontal and transverse plane kinematics at the slower running speed. Hip taping may provide an immediate solution in correcting FKV in running.

scholarly journals Variability of TKR Knee Kinematics and Relationship with Gait Kinetics: Implications for Total Knee Wear

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Valentina Ngai ◽  
Markus A. Wimmer
Keyword(s):  
Force Plate ◽  
Compressive Load ◽  
Knee Kinematics ◽  
Motion Group ◽  
Cluster Technique ◽  
Significant Difference ◽  
Flexion Moment ◽  
Pcl Retaining ◽  
Reaction Forces ◽  
Motion Groups

Several factors, including compressive load and knee kinematics, have been shown to influence wear. External knee moments (a surrogate for load) have recently been correlated with the medial and lateral wear scar areas of an unconstrained, PCL retaining knee design. Therefore, the purpose of this study was to determine whether differences in kinetics during level walking are accompanied by specific differences in relative knee kinematics. Thirty TKR patients were gait tested using the point cluster technique to obtain 3D motions of the knee. External knee moments were calculated from ground reaction forces recorded with a multicomponent force plate. The subjects were separated into two distinct anteroposterior (AP) motion categories: a low motion group and a high motion group. Similarly, the low and high motion groups for internal-external (IE) rotation were also identified. For the IE motion, there was no significant difference between the transverse internal rotation moments between the two IE motion groups. However for the AP motion groups, a higher external peak flexion moment was found for the group displaying less AP motion. These observations suggest that subjects with higher joint moments execute smaller ranges of AP motion and thus are likely to incur less wear.

Relationship Between Knee Walking Kinematics and Muscle Flexibility in Runners

2013 ◽  
Vol 22 (4) ◽  
pp. 279-287 ◽  
Author(s):  
Nathaly Gaudreault ◽  
Alex Fuentes ◽  
Neila Mezghani ◽  
Virginie O. Gauthier ◽  
Katia Turcot
Keyword(s):  
Outcome Measures ◽  
Rotation Angle ◽  
External Rotation ◽  
Three Dimensional ◽  
Knee Kinematics ◽  
Knee Extension ◽  
Iliotibial Band ◽  
Initial Contact ◽  
Knee Angle ◽  
Peak Knee

Context:Decreased flexibility in muscles and joints of lower extremities is commonly observed in runners. Understanding the effect of decreased flexibility on knee walking kinematics in runners is important because, over time, altered gait patterns can make runners vulnerable to overuse injuries or degenerative pathologies.Objectives:To compare hamstring and iliotibial-band (ITB) flexibility and knee kinematics in runners and nonrunners.Design:A descriptive, comparative laboratory study.Setting:Hamstring and ITB flexibility were measured with the active knee-extension test and the modified Ober test, respectively, in both groups of participants. Three-dimensional (3D) walking kinematic data were then recorded at the knee using a motiontracking system.Participants:18 runners and 16 nonrunners.Main Outcome Measures:Knee-extension angle (hamstring flexibility) and hip-adduction angle (ITB flexibility). Knee kinematic parameters of interest included knee angle at initial contact, peak knee angles, and knee-angle range in all planes of movement.Results:The runners had a significantly less flexible ITB than the nonrunners (hip adduction [−] and adduction [+] angles, 3.1° ± 5.6° vs −6.4° ± 4.5°; P < .001). The runners demonstrated a greater mean tibial external-rotation angle at initial contact (7.3° ± 5.8° vs 2.0° ± 4.0°; P = .01) and a smaller mean peak tibial internal-rotation angle (−1.6° ± 3.0° vs −4.2° ± 3.2°; P = .04) than the nonrunners.Conclusion:This study provides new insight into the relationship between muscle flexibility and 3D knee kinematics in runners. This supports the premise that there is an association between muscle flexibility and transverse-plane knee kinematics in this population.

Development of Mucoadhesive Buccal Drug Delivery System of Propranolol Hydrochloride Using Aster ericoides Mucilage

2020 ◽  
Vol 10 (2) ◽  
pp. 133-148
Author(s):  
Ankaj Kaundal ◽  
Pravin Kumar ◽  
Rajendra Awasthi ◽  
Giriraj T. Kulkarni
Keyword(s):  
Buccal Cavity ◽  
Three Dimensional ◽  
Hot Water ◽  
Fickian Diffusion ◽  
Aster Ericoides ◽  
Dimensional Network ◽  
Buccal Tablet ◽  
Significant Difference ◽  
Volunteer Group

Aim: The study was aimed to develop mucoadhesive buccal tablets using Aster ericoides leaves mucilage. Background : Mucilages are naturally occurring high-molecular-weight polyuronides, which have been extensively studied for their application in different pharmaceutical dosage forms. Objective: The objective of the present research was to establish the mucilage isolated from the leaves of Aster ericoides as an excipient for the formulation of the mucoadhesive buccal tablet. Method: The mucilage was isolated from the leaves of Aster ericoides by maceration, precipitated with acetone and characterized. Tablets were prepared using wet granulation technique and evaluated for various official tests. Results: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Conclusion: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Other: However, to prove the potency of the polymer, in vivo bioavailability studies in human volunteers are needed along with chronic toxicity studies in suitable animal models.

scholarly journals Efficacy evaluation of three-dimensional printing assisted osteotomy guide plate in accurate osteotomy of adolescent cubitus varus deformity

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Yuan-Wei Zhang ◽  
Xin Xiao ◽  
Wen-Cheng Gao ◽  
Yan Xiao ◽  
Su-Li Zhang ◽  
...  
Keyword(s):  
3D Printing ◽  
Blood Loss ◽  
Three Dimensional ◽  
Operation Time ◽  
Varus Deformity ◽  
Conventional Group ◽  
Intraoperative Blood Loss ◽  
Cubitus Varus ◽  
Guide Plate ◽  
Significant Difference

Abstract Background This present study is aimed to retrospectively assess the efficacy of three-dimensional (3D) printing assisted osteotomy guide plate in accurate osteotomy of adolescent cubitus varus deformity. Material and methods Twenty-five patients (15 males and 10 females) with the cubitus varus deformity from June 2014 to December 2017 were included in this study and were enrolled into the conventional group (n = 11) and 3D printing group (n = 14) according to the different surgical approaches. The operation time, intraoperative blood loss, osteotomy degrees, osteotomy end union time, and postoperative complications between the two groups were observed and recorded. Results Compared with the conventional group, the 3D printing group has the advantages of shorter operation time, less intraoperative blood loss, higher rate of excellent correction, and higher rate of the parents’ excellent satisfaction with appearance after deformity correction (P < 0.001, P < 0.001, P = 0.019, P = 0.023). Nevertheless, no significant difference was presented in postoperative carrying angle of the deformed side and total complication rate between the two groups (P = 0.626, P = 0.371). Conclusions The operation assisted by 3D printing osteotomy guide plate to correct the adolescent cubitus varus deformity is feasible and effective, which might be an optional approach to promote the accurate osteotomy and optimize the efficacy.

scholarly journals The Effect of Perioral Scan and Artificial Skin Markers on the Accuracy of Virtual Dentofacial Integration: Stereophotogrammetry Versus Smartphone Three-Dimensional Face-Scanning

2020 ◽  
Vol 18 (1) ◽  
pp. 229
Author(s):  
Hang-Nga Mai ◽  
Du-Hyeong Lee
Keyword(s):  
Three Dimensional ◽  
Laser Scanner ◽  
Statistical Analyses ◽  
Integrated Models ◽  
Image Integration ◽  
Positional Accuracy ◽  
Significant Difference ◽  
Face Scanning ◽  
Scanning Systems ◽  
Dimensional Face

This study evaluated the effects of different matching methods on the accuracy of dentofacial integration in stereophotogrammetry and smartphone face-scanning systems. The integration was done (N = 30) with different matching areas (n = 10), including teeth image only (TO), perioral area without markers (PN) and with markers (PM). The positional accuracy of the integrated models was assessed by measuring the midline linear deviations and incisal line canting between the experimental groups and laser scanner-based reference standards. Kruskal–Wallis and Mann–Whitney U tests were used for statistical analyses (α = 0.05). The PM method exhibited the smallest linear deviations in both systems; while the highest deviations were found in the TO in stereophotogrammetry; and in PN in smartphone. For the incisal line canting; the canting degree was the lowest in the PM method; followed by that in the TO and the PN in both systems. Although stereophotogrammetry generally exhibited higher accuracy than the smartphone; the two systems demonstrated no significant difference when the perioral areas were used for matching. The use of perioral scans with markers enables accurate dentofacial image integration; however; cautions should be given on the accuracy of the perioral image obtained without the use of markers.

scholarly journals Prediction accuracy of standard and total keratometry by swept-source optical biometer for multifocal intraocular lens power calculation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hun Lee ◽  
Jae Lim Chung ◽  
Young Jun Kim ◽  
Jae Yong Kim ◽  
Hungwon Tchah
Keyword(s):  
Cataract Surgery ◽  
Case Series ◽  
Intraocular Lenses ◽  
Power Calculation ◽  
Neutral Position ◽  
Swept Source ◽  
Refractive Outcomes ◽  
Case Series Study ◽  
Significant Difference ◽  
Optical Biometer

AbstractWe aimed to compare the refractive outcomes of cataract surgery with diffractive multifocal intraocular lenses (IOLs) using standard keratometry (K) and total keratometry (TK). In this retrospective observational case series study, a total of 302 patients who underwent cataract surgery with multifocal IOL implantation were included. Predicted refractive outcomes were calculated based on the current standard formulas and a new formula developed for TK using K and TK, which were obtained from a swept-source optical biometer. At 2-month postoperatively, median absolute prediction errors (MedAEs) and proportion of eyes within ± 0.50 diopters (D) of predicted postoperative spherical equivalent (SE) refraction were analyzed. There was no significant difference between MedAEs or proportion of eyes within ± 0.50D of predicted refraction from K and TK in each formula. In TFNT00 and 839MP IOL cases, there was no difference between MedAEs from K and TK using any formula. In 829MP IOL cases, MedAE from TK was significantly larger than that from K in Barrett Universal II/Barrett TK Universal II (P = 0.033). In 677MY IOL cases, MedAE from TK was significantly larger than that from K in Haigis (P = 0.020) and Holladay 2 (P = 0.006) formulas. In the subgroup analysis for IOL, there was no difference between the proportion of eyes within ± 0.50 D of predicted refraction from K and TK using any formula. TFNT00 and 839MP IOLs were favorable with TK, with 677MY IOL with K and 829MP IOL being in a neutral position, which necessitates the study that investigates the accuracy of the new TK technology.

“Going Backward”: Effects of age and fatigue on posterior-directed falls in Parkinson disease

2021 ◽  
pp. 1-9
Author(s):  
Evan V. Papa ◽  
Rita M. Patterson ◽  
Nicoleta Bugnariu
Keyword(s):  
Postural Control ◽  
Parkinson Disease ◽  
Repeated Measures ◽  
Center Of Pressure ◽  
Angular Displacement ◽  
Reaction Times ◽  
Older Individuals ◽  
Peak Knee ◽  
Significant Difference ◽  
Fatiguing Exercise

BACKGROUND: Nearly half of persons with Parkinson disease (PD) report fatigue as a factor in their fall history. However, it is unknown whether these self-reported falls are caused by a sensation of fatigue or performance fatigue. OBJECTIVE: We sought to investigate the influences of performance fatigue and age on postural control in persons with PD. METHODS: Individuals with PD (n = 14) underwent postural control assessments before (T0) and immediately after (T1) fatiguing exercise. Biomechanical data were gathered on participants completing a treadmill-induced, posterior-directed fall. Performance fatigue was produced using lower extremity resistance exercise on an isokinetic ergometer. Repeated measures ANCOVAs were used with age as a covariate to determine the effects of performance fatigue on biomechanical variables. RESULTS: After adjustment for age, there was a statistically significant difference in peak center of pressure (COP) latency during the support phase of recovery. Pairwise comparisons demonstrated a decrease in peak ankle displacement from T0 to T1. Age was also found to be significantly related to reaction time and peak knee displacement while participants were fatigued. CONCLUSIONS: The decreased peak COP latency, along with decreased ankle angular displacement, suggest that persons with PD adopt a stiffening strategy in response to backward directed falls. Postural stiffening is not uncommon in persons with PD and could be a risk factor for falls. Older individuals with PD demonstrate slower mobility scores and decreased reaction times in the setting of fatigue, suggesting a combined effect of the aging and fatigue processes.

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