Biomechanics Commons^™

Haptic Portable Robotic Device For Automated Guidewire Or Catheter Navigation In Endovascular Procedures, Vahid Mohammadi, Jason Mactaggart, Majid Jadidi, Alexey Kamenskiy

Journal Articles

Purpose

Endovascular therapy is preferred over open surgery due to its minimally invasive nature, faster recovery, and lower perioperative risk; however, fluoroscopy guided procedures are limited by radiation exposure, high equipment costs, and reliance on highly skilled operators. This study aims to develop and evaluate a lightweight, portable robotic system for autonomous guidewire navigation to improve safety, accessibility, and operator independence.

Methods

A compact 400 g robotic device was designed with millimeter scale positioning accuracy, servo current-based real-time haptic feedback, precise axial rotation, automated retraction advance control, and compatibility with standard endovascular tools. Miniature linear actuated servomotors replicate skilled manual …

Biomechanical Characterization Of Porcine Lower Limb Arteries For Preclinical Evaluation Of Peripheral Vascular Devices, Barbara Batista De Oliveira, Frazer Heinis, Anastasia Desyatova, Jason Mactaggart, Alexey Kamenskiy

Journal Articles

Purpose Peripheral artery disease (PAD) predominantly affects the lower extremities, where complex biomechanical deformations during limb flexion contribute to disease progression and treatment failure. While human and cadaver studies have characterized these deformations, preclinical device testing requires large-animal models that replicate human arterial anatomy and biomechanics. Swine are commonly used, yet their biomechanical comparability to humans remains poorly defined. Methods We performed a detailed morphometric and biomechanical analysis of the external iliac (EIA), superficial femoral (SFA), and popliteal (PA) arteries in 20 Yucatan and 16 domestic swine using computed tomography angiography. Arteries were evaluated in straight and flexed limb postures …

Chitosan Nanofibrous Dressing Increased Angiogenesis And Anti-Inflammatory Response In An Acute Wound Model In Rats: A Comparative Study, Yury Salkovskiy, Mahboubeh Ghanbari, Carlos P Jara, Sara Cartwright, Pinaki Mondal, Colman Freel, Sayed Ahmadreza Razian, Jason Mactaggart, Mark A. Carlson

Journal Articles

Purpose

Chitosan-based materials are promising for wound healing because of their antibacterial efficacy, biocompatibility, and biodegradability, though their healing mechanisms remain unclear. This study explores the cellular and molecular mechanisms of wound healing with chitosan nanofibrous dressings.

Methods

Thirty-nine Sprague Dawley rats were divided into three groups based on the type of dressings administered: (1) chitosan nanofibrous dressing + transparent film, (2) commercial scaffold + transparent film, and (3) transparent film alone (control). Full-thickness wounds (2 cm × 2 cm) were created on the dorsum, splinted, and covered with dressings. Evaluations at 7, 14, and 21 days included histological analysis, …

The Illusion Of Internal Models In Biological Movement, Madhur Mangalam

Journal Articles

The concept of internal models dominates contemporary theories of sensorimotor control, with researchers across neurosciences, specifically motor control, routinely explaining observed behaviors through computational representations that supposedly exist within the nervous system. In this perspective, I present a critical examination of internal model frameworks in sensorimotor control. I argue that representational approaches mischaracterize biological systems for several fundamental reasons: (1) Internal models require homuncular interpreters, creating infinite regress problems; (2) The purported neural implementations of internal models remain empirically elusive despite decades of research; (3) Biological movement systems exhibit multiscale, nonlinear, and non-Gaussian dynamics that fundamentally defy reduction to conventional …

The Myth Of The Bayesian Brain, Madhur Mangalam

Journal Articles

The Bayesian brain hypothesis—the idea that neural systems implement or approximate Bayesian inference—has become a dominant framework in cognitive neuroscience over the past two decades. While mathematically elegant and conceptually unifying, this paper argues that the hypothesis occupies an ambiguous territory between useful metaphor and testable, biologically plausible mechanistic explanation. We critically examine the key claims of the Bayesian brain hypothesis, highlighting issues of unfalsifiability, biological implausibility, and inconsistent empirical support. The framework’s remarkable flexibility in accommodating diverse findings raises concerns about its explanatory power, as models can often be adjusted post hoc to fit virtually any data pattern. We …

An Aquatic Treadmill Alters Lower Limb Walking Dynamics In Typically Developing Children And Children With Cerebral Palsy, Oluwaseye P. Odanye, Joseph Harrington, Aaron Likens, David Kingston, Brian Knarr

Journal Articles

This block-randomized crossover study investigated how a speed-modulated aquatic treadmill (AT) impacts the walking biomechanics of pediatric gait. Eight cerebral palsy (CP) and fifteen typically developing (TD) children walked at normal, slow, and fast treadmill speeds in AT and dry treadmill (DT) conditions. The joint angles of participants were calculated from inertial measurement units to derive sample entropy (SE) measures that quantified the regularity or complexity of motion. A hierarchical statistical model revealed that the CP group had lower SE values for the hip, knee, and ankle joints in the AT and at slower than faster treadmill speeds. Only the …

Kinematic Analysis Of Defensive Forms And Simple Riposte In Foil Fencing And Their Relationship To Target Accuracy, Hashem Adnan Alkilani Dr, Leena Adnan Husain Dr

Journal Articles

This study analyzed kinematic variables of defensive forms and simple riposte in foil fencing and their impact on target accuracy. Eight Jordanian national team fencers (four males, four females, mean age 16.87 ± 2.53 years) participated. Motion analysis was conducted using Contemplas software and Vicon Motus 10 software, with fencing touches recorded electronically. Descriptive statistics, Spearman’s correlation, and repeated measures ANOVA were applied. Results showed the fastest defensive reaction was diagonal defense (0.30s), while horizontal defense achieved the quickest successful touch (0.30s). Increased wrist velocity in the simple riposte after semi-circular defense improved accuracy. The study recommends competition-based training, sensory-cognitive …

Enhancing Walking Performance In Patients With Peripheral Arterial Disease: An Intervention With Ankle-Foot Orthosis, Farahnaz Fallahtafti, Kaeli K. Samson, Zahra Salamifar, Jason M. Johanning, Iraklis Pipinos, Sara A. Myers

Journal Articles

Lower extremity peripheral artery disease (PAD) is a cardiovascular condition manifesting from narrowed or blocked arteries supplying the legs. Gait is impaired in patients with PAD. Recent evidence suggests that walking with carbon fiber ankle foot orthoses (AFOs) can improve patient mobility and delay claudication time. This study aimed to employ advanced biomechanical gait analysis to evaluate the impact of AFO intervention on gait performance among patients with PAD. Patients with claudication had hip, knee, and ankle joint kinetics and kinematics assessed using a cross-over intervention design. Participants walked over the force platforms with and without AFOs while kinematic data …

Lower Limb Revascularization Leads To Faster Walking But With Less Efficient Mechanics In Claudicating Patients, Alex Dzewaltowski, Iraklis Pipinos, Molly Schieber, Jason Johanning, George P. Casale, Sara A. Myers, Philippe Malcolm

Journal Articles

Peripheral artery disease (PAD) is characterized by reduced blood flow to the extremities due to atherosclerosis. Studies report impaired gait mechanics in patients with lower extremity PAD. We hypothesized that revascularization surgery would improve gait mechanics when quantified by net lower limb joint work across the stance phase of walking. We performed gait analyses in 35 patients with PAD and 35 healthy, older adults. Patients with PAD performed a walking protocol prior to and six months following revascularization surgery. Healthy adults only took part in a single walking session. Lower limb joint powers were calculated using inverse dynamics and …

Nonan Gaitprint: An Imu Gait Database Of Healthy Young Adults, Tyler M. Wiles, Madhur Mangalam, Joel H. Sommerfeld, Seung Kyeom Kim, Kolby J. Brink, Anaëlle Charles, Alli Grunkemeyer, Marilena Kalaitzi Manifrenti, Spyridon Mastorakis, Nicholas Stergiou, Aaron Likens

Journal Articles

An ongoing thrust of research focused on human gait pertains to identifying individuals based on gait patterns. However, no existing gait database supports modeling efforts to assess gait patterns unique to individuals. Hence, we introduce the Nonlinear Analysis Core (NONAN) GaitPrint database containing whole body kinematics and foot placement during self-paced overground walking on a 200-meter looping indoor track. Noraxon Ultium MotionTM inertial measurement unit (IMU) sensors sampled the motion of 35 healthy young adults (19–35 years old; 18 men and 17 women; mean ± 1 s.d. age: 24.6 ± 2.7 years; height: 1.73 ± 0.78 m; body mass: …

Quantifying Non-Gaussian Intermittent Fluctuations In Physiology: Multiscale Probability Density Function Analysis Using The Savitzky-Golay Detrending, Madhur Mangalam, Damian G. Kelty-Stephen, Eiichi Watanabe, Ken Kiyono

Journal Articles

When measuring physiological data, the central limit theorem typically implies a consistent variance, resulting in data that closely follow a Gaussian distribution. However, physiological measurements often deviate from this expectation, increasing variance due to nonlinear correlations across various scales. The challenge lies in testing these tails, which comprise only rare and extreme values. We introduce multiscale probability density function (PDF) analysis, a method that estimates this non-Gaussianity parameter for physiological fluctuations in each of multiple timescales. We gain valuable insights into the observed distributions with heavier tails and nonlinear correlations by exploring the relationship between non-Gaussianity and logarithmic scale. To …

Multifractality In Stride-To-Stride Variations Reveals That Walking Involves More Movement Tuning And Adjusting Than Running, Taylor J. Wilson, Madhur Mangalam, Nicholas Stergiou, Aaron Likens

Journal Articles

Introduction: The seemingly periodic human gait exhibits stride-to-stride variations as it adapts to the changing task constraints. The optimal movement variability hypothesis (OMVH) states that healthy stride-to-stride variations exhibit “fractality”—a specific temporal structure in consecutive strides that are ordered, stable but also variable, and adaptable. Previous research has primarily focused on a single fractality measure, “monofractality.” However, this measure can vary across time; strideto-stride variations can show “multifractality.” Greater multifractality in stride-tostride variations would highlight the ability to tune and adjust movements more.

Methods: We investigated monofractality and multifractality in a cohort of eight healthy adults during self-paced walking and …

Temporal Organization Of Stride-To-Stride Variations Contradicts Predictive Models For Sensorimotor Control Of Footfalls During Walking, Madhur Mangalam, Damian G. Kelty-Stephen, Joel H. Sommerfeld, Nicholas Stergiou, Aaron Likens

Journal Articles

Walking exhibits stride-to-stride variations. Given ongoing perturbations, these variations critically support continuous adaptations between the goal-directed organism and its surroundings. Here, we report that stride-to-stride variations during self-paced overground walking show cascade-like intermittency—stride intervals become uneven because stride intervals of different sizes interact and do not simply balance each other. Moreover, even when synchronizing footfalls with visual cues with variable timing of presentation, asynchrony in the timings of the cue and footfall shows cascade-like intermittency. This evidence conflicts with theories about the sensorimotor control of walking, according to which internal predictive models correct asynchrony in the timings of the cue …

Coordination Rigidity In The Gait, Posture, And Speech Of Persons With Parkinson’S Disease, Dobromir Dotov, Valérie Cochen De Cock, Valérie Driss, Benoît Brady, Simone Dalla Bella

Journal Articles

Parkinson’s disease (PD) is associated with reduced coordination abilities. These can result either in random or rigid patterns of movement. The latter, described here as coordination rigidity (CR), have been studied less often. We explored whether CR was present in gait, quiet stance, and speech—tasks involving coordination among multiple joints and muscles. Kinematic and voice recordings were used to compute measures describing the dynamics of systems with multiple degrees of freedom and nonlinear interactions. After clinical evaluation, patients with moderate stage PD were compared against matched healthy participants. In the PD group, gait dynamics was associated with decreased dynamic divergence—lower …

Ergodic Characterization Of Nonergodic Anomalous Diffusion Processes, Madhur Mangalam, Ralf Metzler, Damian G. Kelty-Stephen

Journal Articles

Anomalous diffusion in various complex systems abounds in nature and spans multiple space and time scales. Canonical characterization techniques that rely upon mean squared displacement break down for nonergodic processes, making it challenging to characterize anomalous diffusion from an individual time-series measurement. Nonergodicity reigns when the time-averaged mean square displacement differs from the ensemble-averaged mean squared displacement even in the limit of long measurement series. In these cases, the typical theoretical results for ensemble averages cannot be used to understand and interpret data acquired from time averages. The difficulty then lies in obtaining statistical descriptors of the measured diffusion process …

Betaglycan Promoter Activity Is Differentially Regulated During Myogenesis In Zebrafish Embryo Somites, Lizbeth Ramírez-Vidal, Tonatiuh Molina-Villa, Valentín Mendoza, Carlos Alberto Peralta-Álvarez, Augusto Cesar Poot-Hernández, Dobromir Dotov, Fernado López-Casillas

Journal Articles

Background

Betaglycan, also known as the TGFβ type III receptor (Tgfbr3), is a co-receptor that modulates TGFβ family signaling. Tgfbr3 is upregulated during C2C12 myoblast differentiation and expressed in mouse embryos myocytes.

Results

To investigate tgfbr3 transcriptional regulation during zebrafish embryonic myogenesis, we cloned a 3.2 kb promoter fragment that drives reporter transcription during C2C12 myoblasts differentiation and in the Tg(tgfbr3:mCherry) transgenic zebrafish. We detect tgfbr3 protein and mCherry expression in the adaxial cells concomitantly with the onset of their radial migration to become slow-twitch muscle fibers in the Tg(tgfbr3:mCherry). Remarkably, this expression displays …

Long-Term Use Of An Ankle-Foot Orthosis Intervention In Patients With Peripheral Artery Disease Using The Integrated Promoting Action On Research Implementation In Health Services (I-Parihs) Framework, Ayisha Bashir, Danae Dinkel, Iraklis Pipinos, Paul Estabrooks, Jason Johanning, Sara A. Myers

Journal Articles

Background

Peripheral artery disease (PAD) is a cardiovascular disease that limits patients' walking ability. Persistent ankle-foot orthosis (AFO) use may increase the distance patients can walk as well as physical activity.

Purpose

The purpose of the study was to determine the implementation and patients' perspectives related to the use or disuse of the AFO intervention six months post-intervention. This study was guided by a semi-structured interview and survey based on the integrated Promoting Action on Research Implementation in Health Services (i-PARIHS) constructs.

Design

A convergent mixed methods design was used to evaluate participants' perceptions six months following a three-month AFO …

Collective Dynamics Support Group Drumming, Reduce Variability, And Stabilize Tempo Drift, Dobromir Dotov, Lana Delasanta, Daniel J. Cameron, Edward W. Large, Laurel Trainor

Journal Articles

Humans are social animals who engage in a variety of collective activities requiring coordinated action. Among these, music is a defining and ancient aspect of human sociality. Human social interaction has largely been addressed in dyadic paradigms, and it is yet to be determined whether the ensuing conclusions generalize to larger groups. Studied more extensively in non-human animal behavior, the presence of multiple agents engaged in the same task space creates different constraints and possibilities than in simpler dyadic interactions. We addressed whether collective dynamics play a role in human circle drumming. The task was to synchronize in a group …

On The Scaling Properties Of Oscillatory Modes With Balanced Energy, Dobromir Dotov

Journal Articles

Animal bodies maintain themselves with the help of networks of physiological processes operating over a wide range of timescales. Many physiological signals are characterized by 1/f scaling where the amplitude is inversely proportional to frequency, presumably reflecting the multi-scale nature of the underlying network. Although there are many general theories of such scaling, it is less clear how they are grounded on the specific constraints faced by biological systems. To help understand the nature of this phenomenon, we propose to pay attention not only to the geometry of scaling processes but also to their energy. The first key assumption …

Undetectable Very-Low Frequency Sound Increases Dancing At A Live Concert, Daniel J. Cameron, Dobromir Dotov, Erica Flaten, Dan Bosnyak, Michael J. Hove, Laurel Trainor

Journal Articles

Does low frequency sound (bass) make people dance more? Music that makes people want to move tends to have more low frequency sound, and bass instruments typically provide the musical pulse that people dance to1. Low pitches confer advantages in perception and movement timing, and elicit stronger neural responses for timing compared to high pitches2, suggesting superior sensorimotor communication. Low frequency sound is processed via vibrotactile3 and vestibular4 (in addition to auditory) pathways, and stimulation of these non-auditory modalities in the context of music can increase ratings of groove (the pleasurable urge to move to music) …

Joint Angle Variability Is Altered In Patients With Peripheral Artery Disease After Six Months Of Exercise Intervention, Farah Fallahtafti, Zahra Salamifar, Mahdi Hassan, Hafizur Rahman, Iraklis Pipinos, Sara A. Myers

Journal Articles

Supervised exercise therapy (SET) is a conservative non-operative treatment strategy for improving walking performance in patients with peripheral artery disease (PAD). Gait variability is altered in patients with PAD, but the effect of SET on gait variability is unknown. Forty-three claudicating patients with PAD underwent gait analysis before and immediately after a 6-month SET program. Nonlinear gait variability was assessed using sample entropy, and the largest Lyapunov exponent of the ankle, knee, and hip joint angle time series. Linear mean and variability of the range of motion time series for these three joint angles were also calculated. Two-factor repeated measure …

Machine Learning-Based Peripheral Artery Disease Identification Using Laboratory-Based Gait Data, Ali Al-Ramini, Mahdi Hassan, Farah Fallahtafti, Mohammad Ali Takallou, Hafizur Rahman, Basheer Qolomany, Iraklis Pipinos, Fadi Alsaleem, Sara A. Myers

Journal Articles

Peripheral artery disease (PAD) manifests from atherosclerosis, which limits blood flow to the legs and causes changes in muscle structure and function, and in gait performance. PAD is underdiagnosed, which delays treatment and worsens clinical outcomes. To overcome this challenge, the purpose of this study is to develop machine learning (ML) models that distinguish individuals with and without PAD. This is the first step to using ML to identify those with PAD risk early. We built ML models based on previously acquired overground walking biomechanics data from patients with PAD and healthy controls. Gait signatures were characterized using ankle, knee, …

Patient Compliance With Wearing Lower Limb Assistive Devices: A Scoping Review, Ayisha Bashir, Danae Dinkel, Iraklis Pipinos, Jason Johanning, Sara Myers

Journal Articles

Objective

The aim of this scoping review was to identify information on compliance with wearing orthoses and other supportive devices, to discuss the barriers to adherence, and to suggest strategies for improvement based on these findings.

Methods

Online databases of PubMed, Web of Science, and the Cochrane Library were searched for articles about patients’ compliance with regard to lower limb assistive devices. In addition, a methodological quality control process was conducted. Studies were included if in the English language and related to compliance and adherence to the lower limb assistive device. Exclusion was based on first reading the abstract …

Peripheral Artery Disease Affects The Function Of The Legs Of Claudicating Patients In A Diffuse Manner Irrespective Of The Segment Of The Arterial Tree Primarily Involved, Todd Leutzinger, Panagiotis Koutakis, Matthew A. Fuglestad, Hafizur Rahman, Holly Despiegelaere, Mahdi Hassan, Molly Schieber, Jason Johanning, Nick Stergiou, G. Matthew Longo, George P. Casale, Sara A. Myers, Iraklis Pipinos

Journal Articles

Different levels of arterial occlusive disease (aortoiliac, femoropopliteal, multi-level disease) can produce claudication symptoms in different leg muscle groups (buttocks, thighs, calves) in patients with peripheral artery disease (PAD). We tested the hypothesis that different locations of occlusive disease uniquely affect the muscles of PAD legs and produce distinctive patterns in the way claudicating patients walk. Ninety-seven PAD patients and 35 healthy controls were recruited. PAD patients were categorized to aortoiliac, femoropopliteal and multi-level disease groups using computerized tomographic angiography. Subjects performed walking trials both pain-free and during claudication pain and joint kinematics, kinetics, and spatiotemporal parameters were calculated to …

Creating A Shared Musical Interpretation: Changes In Coordination Dynamics While Learning Unfamiliar Music Together, Emily A. Wood, Andrew Chang, Dan Bosnyak, Lucas Klein, Elger Baraku, Dobromir Dotov, Laurel Trainor

Journal Articles

The ability to coordinate with others is fundamental for humans to achieve shared goals. Often, harmonious interpersonal coordination requires learning, such as ensemble musicians rehearing together to synchronize their low-level timing and high-level aesthetic musical expressions. We investigated how the coordination dynamics of a professional string quartet changed as they learned unfamiliar pieces together across eight trials. During all trials, we recorded each musician's body sway motion data, and quantified the group's body sway similarity (cross-correlation) and information flow (Granger causality) on each trial. In line with our hypothesis, group similarity increased, while group information flow decreased significantly across trials. …

Midlands Voices: We Need To Do More To Support Expecting Mothers During And After Pregnancy, Sara A. Myers

Journal Articles

No abstract provided.

Development Of A Rural Childcare Professionals Advisory Board Focused On Mental And Physical Wellbeing, Danae Dinkel, John Rech, Natalie Hanna, Denita Julius, Jennifer Bauman, Tonya Hood-Hytrek, Matthew Bice

Journal Articles

Background. Childcare providers have high rates of stress and obesity, which can have an impact on the care they provide for children. Limited research has described strategies for including childcare providers in the development of wellbeing initiatives, especially in rural areas.
Objective. To describe the creation and acceptability of a rural childcare advisory board focused on childcare providers’ wellbeing as well as the acceptability of a wellbeing summit implemented by the board.
Methods. A collaborative model guided the actions of the advisory board. Acceptability of the board and the summit were assessed via surveys.
Results. Key factors contributing to the …

Assessing Wear Time And Perceptions Of Wearing An Ankle Foot Orthosis In Patients With Peripheral Artery Disease, Danae Dinkel, Mahdi Hassan, John Rech, Holly Despiegelaere, Jason Johanning, Iraklis Pipinos, Sara A. Myers

Journal Articles

Background

Peripheral artery disease (PAD) is a cardiovascular disease that affects walking ability. An ankle foot orthosis (AFO) may improve walking distances in those with PAD. Little research has explored if those with PAD wear a prescribed AFO and their perceptions of wearing the device.

Objective

To assess wear time of an AFO and explore perceptions of wearing the device in patients with PAD.

Design

Convergent mixed methods.

Setting

The study was conducted through a tertiary care medical center, and the research participants used the device in the community.

Participants

Thirty-six patients, all older adult males, were enrolled in this …

Assessing Wear Time And Perceptions Of Wearing An Ankle Foot Orthosis In Patients With Peripheral Artery Disease, Danae Dinkel, Mahdi Hassan, Holly Despiegelaere, Jason Johanning, Iraklis Pipinos, Sara Myers

Journal Articles

Background

Peripheral artery disease (PAD) is a cardiovascular disease that affects walking ability. An ankle foot orthosis (AFO) may improve walking distances in those with PAD. Little research has explored if those with PAD wear a prescribed AFO and their perceptions of wearing the device.

Objective

To assess wear time of an AFO and explore perceptions of wearing the device in patients with PAD.

Design

Convergent mixed methods.

Setting

The study was conducted through a tertiary care medical center, and the research participants used the device in the community.

Participants

Thirty-six patients, all older adult males, were enrolled in this …

Qualitative Analysis Of Colorectal Cancer Screening In Rural Nebraska, Kendra L. Ratnapradipa, Krishtee Napit, Jordan Ranta, Lady Beverly Luma, Danae Dinkel, Tamara Robinson, Laura Schabloske, Shinobu Watanabe-Galloway

Journal Articles

Compared to urban residents, rural populations are less likely to engage in colorectal cancer (CRC) screening. As part of a statewide cancer needs assessment, we aimed to elicit rural perspectives about CRC screening and resources. We conducted three focus groups with rural Nebraska cancer survivors and caregivers (N = 20) in Spring 2021 using a collective case study design. Participant awareness of and knowledge about CRC screening methods varied across focus groups; overall, 95% of participants had heard of colonoscopy. Participants were less familiar with fecal tests and had confusion about them. Colonoscopy was associated with negative perceptions regarding …