Biomechanics Commons^™

The Effects Of Anterior Cruciate Ligament Reconstruction On Tibial Rotation During Pivoting After Descending Stairs, Stavros Ristanis, Giannis Giakas, Christos D. Papageorgiou, Constantina O. Moraiti, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

Recent in vitro research suggests that ACL reconstruction does not restore tibial rotation. This study investigated rotational knee joint stability in vivo during a combined descending and pivoting movement that applies a high rotational load to the knee joint. We studied 20 ACL reconstructed patients (bone–patellar tendon–bone graft) and 15 matched controls with a six-camera optoelectronic system performing the examined movement. In the control group the results showed no significant differences in the amount of tibial rotation between the two sides. No significant differences were also found between the contralateral intact leg of the ACL group and the healthy control. …

Subtalar And Knee Joint Interaction During Running At Various Stride Lengths, Nikolaos Stergiou, Barry T. Bates, Max J. Kurz

Journal Articles

Background: It has been suggested that during running proper coordination between subtalar pronation/supination and knee flexion/extension via tibial rotation is important to attenuate ground reaction impact forces (GRIF). Lack of coordination over time may produce a wide range of injuries. It was hypothesized that increasing stride length would result in higher GRIF. It was also hypothesized that alterations in stride length would result in changes of the subtalar/knee coordination.

Methods: Six subjects ran under three different stride lengths (normal stride, understride and overstride) at their self-selected pace. Sagittal, rear view kinematic data and GRIF kinetic data were collected. The subtalar/knee …

The Aging Human Neuromuscular System Expresses Less Certainty For Selecting Joint Kinematics During Gait, Max J. Kurz, Nikolaos Stergiou

Journal Articles

This investigation quantitatively characterized the certainty of the aging neuromuscular system in selecting a joint range of motion during gait based on the statistical concept of entropy. Elderly and young control groups walked on a treadmill at a self-selected pace. Joint angles were calculated for the ankle, knee and hip. We hypothesized that the aging group would exhibit less certainty in selecting a joint range of motion during gait. Our results supported this hypothesis, and indicated that aged individuals demonstrated statistically less certainty for the knee (16.8%) and hip (24.6%). We suggest that neurophysiological changes associated with aging may result …

The Effect Of Active Exercise On Rectus Femoris Cooling Time, Blaine C. Long

All-Inclusive List of Electronic Theses and Dissertations

Context: The ability for cryotherapy to influence subcutaneous temperature has mainly been considered during resting skeletal muscle. However, most injuries occur when subcutaneous temperatures have been physically active. Objective: The purpose of this study was to evaluate the effect of ice on exercised rectus femoris musculature and the effect of exercise on cooling rectus femoris musculature to 1 0°C below resting temperature. Design and Setting: Two 2 x 2 repeated measures designs were used. The study was conducted in the Sports Injury Research Laboratory at Indiana State University. Subjects: Six (age= 26.0 ± 3.2 yrs, ht = 181.6 ± 2.4cm, …

Compensatory Mechanisms In Anterior Cruciate Ligament Deficiency, Anastasios Papadonikolakis, Lance Cooper, Nikolaos Stergiou, Anastasios D. Georgoulis, Panayotis N. Coucacos

Journal Articles

The literature cites numerous studies involving the analysis of movement patterns in anterior cruciate ligament deficient (ACLD) patients. Although several in vivo biomechanical studies have shown that ACLD patients develop protective mechanisms against degenerative diseases, it seems that these adaptations fail to protect the knee from future pathology. Some authors state that ACLD patients adapt to the injury by avoiding quadriceps contraction during gait when the knee is near full extension. However, others have found increased hamstrings and decreased gastrocnemius activity, which normally contribute to the stability of the knee. It seems that further in vivo biomechanical investigation is required …

Nonlinear Dynamics Indicates Aging Affects Variability During Gait, Ugo H. Buzzi, Nikolaos Stergiou, Max J. Kurz, Patricia A. Hageman, Jack Heidel

Journal Articles

Objective. To investigate the nature of variability present in time series generated from gait parameters of two different age groups via a nonlinear analysis.

Design. Measures of nonlinear dynamics were used to compare kinematic parameters between elderly and young females.

Background. Aging may lead to changes in motor variability during walking, which may explain the large incidence of falls in the elderly.

Methods. Twenty females, 10 younger (20–37 yr) and 10 older (71–79 yr) walked on a treadmill for 30 consecutive gait cycles. Time series from selected kinematic parameters of the right lower extremity were analyzed using nonlinear dynamics. The …

Self Defense Instruction And Its Impact On Physical Self-Efficacy Of Female Cadets At The United States Military Academy, Jason Matthew Winkle

All-Inclusive List of Electronic Theses and Dissertations

The purpose of this study was to determine the impact of self defense instruction of female cadets at the United States Military Academy on their physical self-efficacy. All95 female cadets enrolled in PE115 during the fall of2002 were surveyed on the first and last day of class to determine their levels of perceived physical ability (PPA) and physical self-presentation confidence (PSPC). Both the PP A and the PSPC are subscales ofthe Physical Self-Efficacy Scale (PSE). Completed data were collected from 80 (84 percent) ofthe subjects. Statistical data analysis included descriptive statistics and a 2x2 multivariate analysis of variance (MANOV A). …

Technique Differences In Women's 100m Hurdles Between The Current Hurdle Height Of 84.0 Cm And A Proposed Hurdle Height Of 91.4 Cm, Jason M. Francis

All-Inclusive List of Electronic Theses and Dissertations

This study examined women's 100 rn hurdle technique modifications over the proposed hurdle height of 91.4 ern compared to the current hurdle height of 84.0 ern. The technique modifications were determined by the kinematic variables composed of linear displacements and angular displacements, and the performance variables composed of velocity measures and timing information. Three women collegiate 1 OOrn hurdlers at Indiana State University and one post collegiate hurdler training at Indiana State University volunteered for the study. The athletes finished a six-week conditioning program prior to the start of hurdle training. The athletes were given two weeks or four hurdle …

Nonlinear Analysis Of The Development Of Sitting Postural Control, Regina T. Harbourne, Nikolaos Stergiou

Journal Articles

The development of sitting postural control in five normal infants was examined longitudinally at three stages of sitting: Stage 1, when infants could hold up their head and upper trunk, but could not sit independently; Stage 2, when infants began to sit independently briefly; and Stage 3, when infants could sit independently. Methods from nonlinear dynamics were used to analyze center of pressure (COP) data during sitting in terms of stability of the neuromuscular system (Lyapunov Exponent), movement dimensionality (Correlation Dimension), and complexity/regularity (Approximate Entropy). Results indicated significant changes in the nonlinear measures over time, with increased stability and increased …

The Spanning Set Indicates That Variability During The Stance Period Of Running Is Affected By Footwear, Max J. Kurz, Nikolaos Stergiou

Journal Articles

Sensory information the foot receives appears to be related to kinematic variability. Since footwear material densities affect sensory information, footwear may be an important factor that dictates variability. This study hypothesized that modifications in footwear would result in changes in kinematic variability during the running stance period. Subjects ran on a treadmill for three conditions: hard shoe, soft shoe and barefoot. The spanning sets of the mean ensemble curves of the knee and ankle changes for each condition were used to define variability. Variability was significantly larger in the barefoot condition in comparison with the two footwear conditions for both …

The Short-Term Effects Of Grade 1 And 2 Joint Mobilizations On Subject Pain Range Of Motion And Muscle Activity In The Pathological Lumbar Spine, Sean Hanrahan

Human Movement Studies & Special Education Theses & Dissertations

The purpose of this study was to examine the short-term effects of Grades 1 and 2 posteroanterior joint mobilizations (JM) at the pathological lumbar spine on subject pain, range of motion (ROM), and muscle force. All subjects were determined to have sustained mechanical dysfunction of the lumbar spine of less than 48 hours as assessed through a standardized evaluation. Subjects were randomly assigned to a group; the control group received ice and stretching while the experimental group received JM in addition to ice and stretching. The JM's were performed at 3 consecutive lumbar segments surrounding the area of greatest discomfort. …

Three-Dimensional Tibiofemoral Kinematics Of The Anterior Cruciate Ligament-Deficient And Reconstructed Knee During Walking, Anastasios D. Georgoulis, Anastasios Papadonikolakis, Christos D. Papageorgiou, Argyris Mitsou, Nikolaos Stergiou

Journal Articles

Background: It is possible that gait abnormalities may play a role in the pathogenesis of meniscal or chondral injury as well as osteoarthritis of the knee in patients with anterior cruciate ligament deficiency.

Hypothesis: The three-dimensional kinematics of anterior cruciate ligament-deficient knees are changed even during low-stress activities, such as walking, but can be restored by reconstruction.

Study Design: Case control study.

Methods: Using a three-dimensional optoelectronic gait analysis system, we examined 13 patients with anterior cruciate ligament-deficient knees, 21 patients with anterior cruciate ligament-reconstructed knees, and 10 control subjects with uninjured knees during walking.

Results: Normal patterns of knee …

Hper Biomechanics Laboratory 2002 Annual Report, Issue 1, Nebraska Biomechanics Core Facility

Biomechanics Annual Report

This issue features Development of a gait-o-gram for the assessment of gait, Promising insights on the development of posture in children, A new understanding of Parkinson’s Disease, Assessing the stability of elderly gait, Gait analysis provides the Omaha community with relief from running injuries, Custom Palm pilot software offers scientists and teachers new technology, Helping high school students appreciate science and math, Past students achieve success, Collaborative work with the Orthopedic Center of Sports Medicine at Ioannina-Greece, and 2002 Publications and Presentations

Hydrodynamic Stability Of Swimming In Ostraciid Fishes: Role Of The Carapace In The Smooth Trunkfish Lactophrys Triqueter (Teleostei : Ostraciidae), Ian K. Bartol, Morteza Gharib, Daniel Weihs, Paul W. Webb, Jay R. Hove, Malcolm S. Gordon

Biological Sciences Faculty Publications

The hydrodynamic bases for the stability of locomotory motions in fishes are poorly understood, even for those fishes, such as the rigid-bodied smooth trunkfish Lactophrys triqueter, that exhibit unusually small amplitude recoil movements during rectilinear swimming. We have studied the role played by the bony carapace of the smooth trunkfish in generating trimming forces that self-correct for instabilities. The flow patterns, forces and moments on and around anatomically exact, smooth trunkfish models positioned at both pitching and yawing angles of attack were investigated using three methods: digital particle image velocimetry (DPIV), pressure distribution measurements, and force balance measurements. Models …

Spanning Set Defines Variability In Locomotive Patterns, Max J. Kurz, Nikolaos Stergiou, Daniel Blanke

Journal Articles

The purpose of the investigation was to use the spanning set methodology to quantify variability in locomotive patterns and to compare this method with traditional measures of variability. Subjects ran on a treadmill while sagittal plane kinematic data were collected with a high-speed (180 Hz) camera. Changes in variability were evaluated as the subject ran barefoot and in shoes. Mean ensemble curves for the knee angle during the stance period were created for each condition. From these curves, traditional measures of variability were calculated using the coefficients of variation (CVs), and the mean deviation (MD). Spanning set vectors were defined …