Life Sciences Commons^™

A Biomechanical Analysis Of Back Squats: Motion Capture, Electromyography, And Musculoskeletal Modeling, Eva Maria Urdiales Maddox

Human Movement Sciences Theses & Dissertations

Previous literature evaluating maximal back squats have failed to identify key components of the study decisions and procedures that would allow for duplication. Firstly, the existence of a sticking region in maximally weighted resistance exercises is frequently discussed and has been described as a force-reduced transition phase between an acceleration phase and a strength phase of a lift. However, the etiology has yet to be agreed upon. Second, Electromyography (EMG) is frequently used to assess muscle activations. However, no best practice for EMG normalization has been proposed. Two methods are commonly implemented for normalizing EMG: a maximum voluntary isometric contraction …

Comparison Of Spine–Pelvis Kinematics Variability During Sit-To-Stand And Stand-To-Sit In People With & Without Chronic Low Back Pain: A Vector Coding And Statistical Parametric Mapping Approach, Narges Jangjoo, Elham Alijanpour, Saeid Khodabakhsh, Seyed Sadredin Shojaedin, Roozbeh Naemi

Rehabilitation Sciences Faculty Publications

There is evidence in the literature to suggest that low back pain may change spine–pelvis coordination during activities of daily living. This study aimed to compare the variability of the spine– pelvis coordination during sit-to-stand in people with and without LBP. Ten healthy individuals with a history of LBP and ten individuals without history of LBP participated in this study. Three-dimensional kinematic data of the upper trunk (UT), lower trunk (LT), lower back (LB), and pelvis segments during sit-to-stand and stand-to-sit were recorded using a multi-segmental spine and pelvis models using a motion capture system. The coordination patterns and the …

Utilization Of Finite Element Analysis Techniques For Adolescent Idiopathic Scoliosis Surgical Planning, Michael A. Polanco

Mechanical & Aerospace Engineering Theses & Dissertations

Adolescent Idiopathic Scoliosis, a three-dimensional deformity of the thoracolumbar spine, affects approximately 1-3% of patients ages 10-18. Surgical correction and treatment of the spinal column is a costly and high-risk task that is consistently complicated by factors such as patient-specific spinal deformities, curve flexibility, and surgeon experience. The following dissertation utilizes finite element analysis to develop a cost-effective, building-block approach by which surgical procedures and kinematic evaluations may be investigated. All studies conducted are based off a volumetric, thoracolumbar finite element (FE) model developed from computer-aided design (CAD) anatomy whose components are kinematically validated with in-vitro data. Spinal ligament stiffness …

Turning Performance Of Brief Squid Lolliguncula Brevis During Attacks On Shrimp And Fish, Rachel A. Jastrebsky, Ian K. Bartol, Paul S. Krueger

Biological Sciences Faculty Publications

Although squid are generally considered to be effective predators, little is currently known of how squid maneuver and position themselves during prey strikes. In this study, high-speed video and kinematic analyses were used to study attacks by the brief squid Lolliguncula brevis on both shrimp and fish. Squid attack successwas high (>80%) and three behavioral phases were identified: (1) approach, (2) strike and (3) recoil. Lolliguncula brevis demonstrated greater maneuverability (i.e. a smaller length-specific turning radius) and employed more body adjustments (i.e. mantle angle posturing) during approaches toward shrimp versus fish. Squid exhibited higher linear approach/strike velocities and accelerations …

Sagittal Plane Gait Kinematics In Individuals With Chronic Ankle Instability, Matthew C. Hoch, David R. Mullineaux, Kyoungkyu Jeon, Patrick O. Mckeon

Rehabilitation Sciences Faculty Publications

Single joint kinematic alterations have been identified during gait in those with chronic ankle instability (CAI). The purpose of this study was to compare sagittal plane hip, knee, and ankle kinematics during walking in participants with and without CAI. Twelve individuals with CAI and 12 healthy individuals walked on a treadmill at 1.5 m/s. Three-dimensional kinematics were analyzed using mean ensemble curves and independent t tests. Participants with CAI demonstrated less lower extremity flexion during the absorption phase of stance and the limb placement phase of swing, which may have implications for limb placement at initial contact.

Kinematics And Hydrodynamics Of Cephalopod Turning Performance In Routine Swimming And Predatory Attacks, Rachel A. Jastrebsky

Biological Sciences Theses & Dissertations

Steady rectilinear swimming has received considerable attention in aquatic animal locomotion studies. Unsteady swimming movements, however, represent a large portion of many aquatic animals’ locomotive repertoire and have not been examined extensively. This study incorporates kinematic analyses of routine turning performance of brief squid Lolliguncula brevis and dwarf cuttlefish Sepia bandensis (Chapter 2), 3D velocimetry techniques to examine hydrodynamic turning performance of L. brevis (Chapter 3) and kinematic analyses of turning performance of L. brevis during predatory attacks on shrimp and fish prey (Chapter 4).

Both L. brevis and S. bandensis demonstrated high maneuverability, having the lowest measures of length-specific …

The Effects Of A Semi-Rigid Ankle Brace On A Simulated Isolated Subtalar Joint Instability, Julie Choisne, Matthew C. Hoch, Sebastian Bawab, Ian Alexander, Stacie I. Ringleb

Mechanical & Aerospace Engineering Faculty Publications

Subtalar joint instability is hypothesized to occur after injuries to the calcaneofibular ligament (CFL) in isolation or in combination with the cervical and the talocalcaneal interosseous ligaments. A common treatment for hindfoot instability is the application of an ankle brace. However, the ability of an ankle brace to promote subtalar joint stability is not well established. We assessed the kinematics of the subtalar joint, ankle, and hindfoot in the presence of isolated subtalar instability, investigated the effect of bracing in a CFL deficient foot and with a total rupture of the intrinsic ligaments, and evaluated how maximum inversion range of …

Effects Of Lateral Ligament Sectioning On The Stability Of The Ankle And Subtalar Joint, Stacie I. Ringleb, Ajaya Dhakal, Claude D. Anderson, Sebastian Bawab, Rajesh Paranjape

Mechanical & Aerospace Engineering Faculty Publications

Patients with subtalar joint instability are often diagnosed with ankle instability. Only after a prolonged period of time in which a patient does not improve after treatment for ankle instability is subtalar joint instability considered. To develop a clinically relevant method to diagnose subtalar joint instability, the kinematics of the simulated unstable subtalar joint were examined. A 6 degree-of-freedom positioning and loading device was developed. Plantarflexion/dorsiflexion, inversion/eversion, and internal/external rotation were applied individually or as coupled motions along with an anterior/posterior drawer. Kinematic data were collected from sensors attached to the calcaneus, talus, and tibia by keeping all the ligaments …

Evidence Of Self-Correcting Spiral Flows In Swimming Boxfishes, I. K. Bartol, M. S. Gordon, P. Webb, D. Weihs, M. Gharib

Biological Sciences Faculty Publications

The marine boxfishes have rigid keeled exteriors (carapaces) unlike most fishes, yet exhibit high stability, high maneuverability and relatively low drag given their large cross-sectional area. These characteristics lend themselves well to bioinspired design. Based on previous stereolithographic boxfish model experiments, it was determined that vortical flows develop around the carapace keels, producing self-correcting forces that facilitate swimming in smooth trajectories. To determine if similar self-correcting flows occur in live, actively swimming boxfishes, two species of boxfishes (Ostracion meleagris and Lactophrys triqueter) were induced to swim against currents in a water tunnel, while flows around the fishes were quantified …