Musculoskeletal System Commons^™

Osteoblast-Derived Fgf9 Regulates Skeletal Homeostasis, Liping Wang, Theresa M. Roth, Marcia J. Abbott, Linh Ho, Lalita Wattanachanya, Robert A. Nissenson

Health Sciences and Kinesiology Faculty Articles

FGF9 has complex and important roles in skeletal development and repair. We have previously observed that Fgf9 expression in osteoblasts (OBs) is regulated by G protein signaling and therefore the present study was done to determine whether OB-derived FGF9 was important in skeletal homeostasis. To directly test this idea, we deleted functional expression of Fgf9 gene in OBs using a 2.3 kb collagen type I promoter-driven Cre transgenic mouse line (Fgf9^{OB −/−}). Both Fgf9 knockout (Fgf9^{OB −/−}) and the Fgf9 floxed littermates (Fgf9^fl/fl) mice were fully backcrossed and maintained in an FBV/N background. Three …

Dual-Task Does Not Increase Slip And Fall Risk In Healthy Young And Older Adults During Walking, Rahul Soangra, Thurmon Lockhart

Physical Therapy Faculty Articles and Research

Dual-task tests can identify gait characteristics peculiar to fallers and nonfallers. Understanding the relationship between gait performance and dual-task related cognitive-motor interference is important for fall prevention. Dual-task adapted changes in gait instability/variability can adversely affect fall risks. Although implicated, it is unclear if healthy participants’ fall risks aremodified by dual-task walking conditions. Seven healthy young and seven healthy older adults were randomly assigned to normal walking and dual-task walking sessions with a slip perturbation. In the dual-task session, the participants walked and simultaneously counted backwards from a randomly provided number. The results indicate that the gait changes in dual-task …

Il-15 Activates The Jak3/Stat3 Signaling Pathway To Mediate Glucose Uptake In Skeletal Muscle Cells, James E. Krolopp, Shantaé M. Thornton, Marcia J. Abbott

Health Sciences and Kinesiology Faculty Articles

Myokines are specialized cytokines that are secreted from skeletal muscle (SKM) in response to metabolic stimuli, such as exercise. Interleukin-15 (IL-15) is a myokine with potential to reduce obesity and increase lean mass through induction of metabolic processes. It has been previously shown that IL-15 acts to increase glucose uptake in SKM cells. However, the downstream signals orchestrating the link between IL-15 signaling and glucose uptake have not been fully explored. Here we employed the mouse SKM C2C12 cell line to examine potential downstream targets of IL-15-induced alterations in glucose uptake. Following differentiation, C2C12 cells were treated overnight with 100 …

Adaptations Of Lumbar Biomechanics After Four Weeks Of Running Training With Minimalist Footwear And Technique Guidance: Implications For Running-Related Lower Back Pain, Szu-Ping Lee, Joshua P. Bailey, Jo Armour Smith, Stephanie Barton, David Brown, Talia Joyce

Physical Therapy Faculty Articles and Research

Objectives

To investigate the changes in lumbar kinematic and paraspinal muscle activation before, during, and after a 4-week minimalist running training.

Design

Prospective cohort study.

Setting

University research laboratory.

Participants

Seventeen habitually shod recreational runners who run 10–50 km per week.

Main outcome measures

During stance phases of running, sagittal lumbar kinematics was recorded using an electrogoniometer, and activities of the lumbar paraspinal muscles were assessed by electromyography. Runners were asked to run at a prescribed speed (3.1 m/s) and a self-selected speed.

Results

For the 3.1 m/s running speed, significant differences were found in the calculated mean lumbar posture …

Reduction Of Friction By Recombinant Human Proteoglycan 4 In Il-1Α Stimulated Bovine Cartilage Explants, Katherine M. Larson, Ling Zhang, Khaled A. Elsaid, Tannin A. Schmidt, Braden C. Fleming, Gary J. Badger, Gregory D. Jay

Pharmacy Faculty Articles and Research

A boundary lubricant attaches and protects sliding bearing surfaces by preventing interlocking asperity-asperity contact. Proteoglycan-4 (PRG4) is a boundary lubricant found in the synovial fluid that provides chondroprotection to articular surfaces. Inflammation of the diarthrodial joint modulates local PRG4 concentration. Thus, we measured the effects of inflammation, with Interkeukin-1α (IL-1α) incubation, upon boundary lubrication and PRG4 expression in bovine cartilage explants. We further aimed to determine whether the addition of exogenous human recombinant PRG4 (rhPRG4) could mitigate the effects of inflammation on boundary lubrication and PRG4 expression in vitro.

Cartilage explants, following a 7-day incubation with IL-1α, were tested …

Can Gait Signatures Provide Quantitative Measures For Aiding Clinical Decision-Making? A Systematic Meta-Analysis Of Gait Variability Behavior In Patients With Parkinson’S Disease, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

A disturbed, inconsistent walking pattern is a common feature of patients with Parkinson's disease (PwPD). Such extreme variability in both temporal and spatial parameters of gait has been associated with unstable walking and an elevated prevalence of falls. However, despite their ability to discretise healthy from pathological function, normative variability values for key gait parameters are still missing. Furthermore, an understanding of each parameter's response to pathology, as well as the inter-parameter relationships, has received little attention. The aim of this systematic literature review and meta-analysis was therefore to define threshold levels for pathological gait variability as well as to …

How Should We Teach Lumbar Manipulation? A Consensus Study, Michael O'Donnell, Jo Armour Smith, Alex Abzug, Kornelia Kulig

Physical Therapy Faculty Articles and Research

Background Spinal manipulation is an effective intervention for low back pain, yet there is little consistency in how this skill is taught.

Objectives The purpose of this study was to identify what educators and clinicians believe are important characteristics of the patient and operator position prior to side-lying lumbar manipulation and the patient position and operator motion during the manipulative thrust.

Design A multi-disciplinary correspondence-based Delphi method

Methods Three rounds of questionnaires were sent to physical therapists, osteopaths and chiropractors. Consensus was established in Round 3 if at least 75 % of respondents identified a characteristic as very important/extremely important …

Revealing The Quality Of Movement: A Meta-Analysis Review To Quantify The Thresholds To Pathological Variability During Standing And Walking, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

Neuromotor processes are inherently noisy, which results in variability during movement and fluctu-ations in motor control. Although controversial, low levels of variability are traditionally considered healthy, while increased levels are thought to be pathological. This systematic review and meta-analysisof the literature investigates the thresholds between healthy and pathological task variability.

After examining 13,195 publications, 109 studies were included. Results from over 3000 healthy sub-jects and 2775 patients revealed an overall positive effect size of pathology on variability of 0.59 forwalking and 0.80 for sway. For the coefficient of variation of stride time (ST) and sway area (SA), upperthresholds of 2.6% …

Trunk-Pelvis Coordination During Turning: A Cross Sectional Study Of Young Adults With And Without A History Of Low Back Pain, Jo Armour Smith, Kornelia Kulig

Physical Therapy Faculty Articles and Research

Background

During steady-state locomotion, symptomatic individuals with low back pain demonstrate reduced ability to modulate coordination between the trunk and the pelvis in the axial plane. It is unclear if this is also true during functional locomotor perturbations such as changing direction, or if this change in coordination adaptability persists between symptomatic episodes. The purpose of this study was to compare trunk-pelvis coordination during walking turns in healthy individuals and asymptomatic individuals with a history of low back pain.

Methods

Participants performed multiple ipsilateral turns. Axial plane inter-segmental coordination and stride-to-stride coordination variability were quantified using the vector coding technique. …

Altered Multifidus Recruitment During Walking In Young Asymptomatic Individuals With A History Of Low Back Pain, Jo Armour Smith, Kornelia Kulig

Physical Therapy Faculty Articles and Research

Study Design

Cross sectional, laboratory study.

Background

Individuals with low back pain have impaired activation of multifidus during postural adjustments and increased activity of the erector spinae musculature during walking. However, it is unclear if these alterations in muscle activity are evident during locomotion in individuals with a history of low back pain when they are between symptomatic episodes.

Objectives

To compare paraspinal muscle activity in young healthy individuals and young individuals with a history of low back pain during walking turns.

Methods

14 asymptomatic individuals with a history of low back pain and 14 controls performed 90° walking turns …

Il-15 Mediates Mitochondrial Activity Through A Ppar𝛿-Dependent-Ppar𝛼-Independent Mechanism In Skeletal Muscle Cells, Shantaé M. Thornton, James E. Krolopp, Marcia J. Abbott

Health Sciences and Kinesiology Faculty Articles

Molecular mediators of metabolic processes, to increase energy expenditure, have become a focus for therapies of obesity. The discovery of cytokines secreted from the skeletal muscle (SKM), termed “myokines,” has garnered attention due to their positive effects on metabolic processes. Interleukin-15 (IL-15) is a myokine that has numerous positive metabolic effects and is linked to the PPAR family of mitochondrial regulators. Here, we aimed to determine the importance of PPAR𝛼 and/or PPAR𝛿 as targets of IL-15 signaling. C2C12 SKM cells were differentiated for 6 days and treated every other day with IL-15 (100 ng/mL), a PPAR𝛼 inhibitor (GW-6471), a PPAR𝛿 …

Effects Of Pelvis Impact Angle And Hip Muscle Forces On Hip Fracture Risk During A Fall Using An Advanced Hip Impact Simulator, Woochol J. Choi, Stephen N. Robinovitch

Physical Therapy Faculty Articles and Research

"Over 90% of hip fractures in older adults are caused by falls [1]. Whether a given fall will cause hip fracture depends on bone strength, and on the impact force and stress applied to the bone during impact [2]. Improved understanding is required on how peak bone stresses during a fall depend on the mechanics of a fall, and on the state of contraction at the moment of impact of the muscles spanning the hip. Recently, Choi et al showed that, for lateral impact to the hip, peak stresses decrease with increases in hip abductor muscle force [3]. In the …

Influence Of Pelvis Impact Angle During A Fall: On The Protective Benefit Of Hip Protectors, Woochol J. Choi, Stephen N. Robinovitch

Physical Therapy Faculty Articles and Research

"Over 90% of hip fractures are due to falls [1]. Laboratory measures have shown that wearable hip protectors reduce impact forces to the proximal femur during a simulated sideways fall on the hip [2, 3]. However, clinical evidence suggests that hip fractures still occur when hip protectors are worn [4]. Furthermore, while falls in real life result in a variety of impact configurations, biomechanical tests to date have focused only on lateral impact to the pelvis. In the current study, we examined how the force reduction provided by wearable hip protectors is affected by pelvis impact configuration during simulated sideways …

Negative Skeletal Effects Of Locally Produced Adiponectin, Marcia J. Abbott, Theresa M. Roth, Linh Ho, Liping Wang, Dylan O'Carroll, Robert A. Nissenson

Health Sciences and Kinesiology Faculty Articles

Epidemiological studies show that high circulating levels of adiponectin are associated with low bone mineral density. The effect of adiponectin on skeletal homeostasis, on osteoblasts in particular, remains controversial. We investigated this issue using mice with adipocyte-specific over-expression of adiponectin (AdTg). MicroCT and histomorphometric analysis revealed decreases (15%) in fractional bone volume in AdTg mice at the proximal tibia with no changes at the distal femur. Cortical bone thickness at mid-shafts of the tibia and at the tibiofibular junction was reduced (3–4%) in AdTg mice. Dynamic histomorphometry at the proximal tibia in AdTg mice revealed inhibition of bone formation. AdTg …

Does Insertion Of Intramuscular Electromyographic Electrodes Alter Motor Behavior During Locomotion?, Jo Armour Smith, Kornelia Kulig

Physical Therapy Faculty Articles and Research

Intramuscular electromyography (EMG) is commonly used to quantify activity in the trunk musculature. However, it is unclear if the discomfort or fear of pain associated with insertion of intramuscular EMG electrodes results in altered motor behavior. This study examined whether intramuscular EMG affects locomotor speed and trunk motion, and examined the anticipated and actual pain associated with electrode insertion in healthy individuals and individuals with a history of low back pain (LBP). Before and after insertion of intramuscular electrodes into the lumbar and thoracic paraspinals, participants performed multiple repetitions of a walking turn at self-selected and controlled average speed. Low …

The Effects Of A Caloric Restrictive Diet On Bone Mineral Density And Bone Strength In Male And Female Rats, Haley Folta

Student Scholar Symposium Abstracts and Posters

The purpose of this study was to determine the existence of sex differences following a 40% caloric restrictive diet and its impact on tibial bone mineral density (BMD) and bone strength between male and female rats. Thirty-two, six-week old Sprague Dawley rats (16 males and 16 females) were randomly divided into an ad libitum fed control group (MC, n=8 and FC, n=8) and a pair fed diet group placed on the 40% caloric restriction (MD, n=8 and FD, n=8) for a 6 week period. The caloric restrictive diet was equivalent to the normal fed diet in vitamin and mineral content …

The Impact Of A 20% Vs. A 40% Caloric Restrictive Diet On Bone Mineral Density During The Growth Period In Male Rats, Kassandra Lee

Student Scholar Symposium Abstracts and Posters

Purpose: The purpose of this study was to determine the impact of a 20% and a 40% caloric restrictive diet on bone mineral density (BMD) and bone strength in male rats during the growth period. Methods: 32 male rats were randomly divided into: control groups (C20, n=8 and C40, n=8), a group fed the 20% caloric restrictive diet (D20, n=8), and a group fed the 40% caloric restrictive diet (D40, n=8). An animal in the caloric restrictive diet group was matched and pair fed with an animal in the control group for 6 weeks. Each caloric restrictive diet contained additional …

Hydatid Cyst Of Thoracic Spine: A Rare Cause Of Paraplegia, Rahul Soangra, Mool Chand Soangra

Physical Therapy Faculty Articles and Research

Primary spinal hydatid cysts are uncommon and extradural involvement is rare. We report an unusual case of Paraplegia due to hydatid disease of primary site of infection extra spinal muscles in thoracic region from T5 to T8 level extending into a daughter cyst at T9 level, is main cause of acute Paraplegia. Magnetic resonance imaging (MRI) showed an extradural round cystic lesion in the spinal canal filling the posterior and left postero-lateral expect at T9 level, markedly compressing the cord. The cyst was removed after laminectomy and opening of the dural sac, with excision of extraspinal mass in left paravertebral …

Innovative Evaluation Of Dexterity In Pediatrics, Susan V. Duff, Dorit H. Aaron, Gloria R. Gogola, Francisco J. Valero-Cuevas

Physical Therapy Faculty Articles and Research

Introduction

Hand dexterity is multifaceted and essential to the performance of daily tasks. Timed performance and precision demands are the most common features of quantitative dexterity testing. Measurement concepts such as rate of completion, in-hand manipulation and dynamic force control of instabilities are being integrated into assessment tools for the pediatric population.

Purpose

To review measurement concepts inherent in pediatric dexterity testing and introduce concepts that are infrequently measured or novel as exemplified with two assessment tools.

Methods

Measurement concepts included in common assessment tools are introduced first. We then describe seldom measured and novel concepts embedded in two instruments; …

Clinical Assessment Of The Infant And Child Following Perinatal Brachial Plexus Injury, Susan V. Duff, Carol Dematteo

Physical Therapy Faculty Articles and Research

Introduction

After perinatal brachial plexus injury (PBPI), clinicians play an important role in injury classification as well as the assessment of recovery and secondary conditions. Early assessment guides the initial plan of care and influences follow-up and long-term outcome.

Purpose

To review methods used to assess, classify and monitor the extent and influence of PBPI with an emphasis on guidelines for clinicians.

Methods

We use The International Classification of Functioning, Disability, and Health (ICF) model to provide a guide to assessment after PBPI for rehabilitation clinicians.

Discussion

With information gained from targeted assessments, clinicians can design interventions to increase the …

The Effect Of Chronic Sleep Deprivation On Tumor Necrosis Factor Alpha And Bone Health In Peri-Menopausal Rats, Megan Robertson, Derek Booth, Erin Wainwright, Cody Arbuckle, Frank Frisch

Student Scholar Symposium Abstracts and Posters

Post-menopausal osteoporosis is a common syndrome in the United States. The cessation of estrogen signaling coupled with the production of pro-inflammatory cytokines from sleep deprivation leads to an even greater risk of post-menopausal osteoporosis by creating an imbalance between osteoblasts and osteoclasts. With estrogen no longer present to regulate the concentration of osteoclasts and pro-inflammatory cytokines increasing production of osteoclasts, bone is degraded at a faster rate than it is formed. One of the most common treatments for osteoporosis is Zolendronate (a nitrogenous bisphosphonate), which decreases the number of osteoclasts in bone. This preliminary study looked at the effects on …

Identification Of Functional Parameters For The Classification Of Older Female Fallers And Prediction Of ‘First-Time’ Fallers, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

Falls remain a challenge for ageing societies. Strong evidence indicates that a previous fall is the strongest single screening indicator for a subsequent fall and the need for assessing fall risk without accounting for fall history is therefore imperative. Testing in three functional domains (using a total 92 measures) were completed in 84 older women (60–85 years of age), including muscular control, standing balance, and mean and variability of gait. Participants were retrospectively classified as fallers (n = 38) or non-fallers (n = 42) and additionally in a prospective manner to identify first-time fallers (FTFs) (n = 6) within a …

Fall Risk Prediction Using Wearable Wireless Sensors, Thurmon Lockhart, Chris Frame, Rahul Soangra, John Lach

Physical Therapy Faculty Articles and Research

Wearable wireless sensors and nonlinear dynamics identify postural characteristics relevant to balance control and dynamic stability, revealing predictive risk of falls among older adults.

Classifying Lower Extremity Muscle Fatigue During Walking Using Machine Learning And Inertial Sensors, Jian Zhang, Thurmon Lockhart, Rahul Soangra

Physical Therapy Faculty Articles and Research

Fatigue in lower extremity musculature is associated with decline in postural stability, motor performance and alters normal walking patterns in human subjects. Automated recognition of lower extremity muscle fatigue condition may be advantageous in early detection of fall and injury risks. Supervised machine learning methods such as Support Vector Machines (SVM) have been previously used for classifying healthy and pathological gait patterns and also for separating old and young gait patterns. In this study we explore the classification potential of SVM in recognition of gait patterns utilizing an inertial measurement unit associated with lower extremity muscular fatigue. Both kinematic and …

Potential For Using Smartphone Accelerometers In Non-Laboratory Environments, Rahul Soangra, Thurmon Lockhart, Christopher W. Frames, Jian Zhang, Seong Hyun Moon, Jongsoon Park

Physical Therapy Faculty Articles and Research

In recent years, there has been rising interest in using accelerometers as an alternative instrument to measure the center of pressure. Accelerometers are inexpensive, small, sensitive, and can be readily used in non-laboratory environments. In addition to this, smartphones with built-in accelerometers add to their capability with real-time processing of data from sensors. Clinicians and researchers are currently in disagreement from whether these measurements provide the same physiological information about the participant’s balance. In this study, twelve participants were asked to wear smartphone on their right ASIS using a belt clip and stand still on the forceplate. The data was …

Trunk Coordination In Dancers And Non-Dancers, Danielle N. Jarvis, Jo Armour Smith, Kornelia Kulig

Physical Therapy Faculty Articles and Research

Variability, or how a task changes across trials, may reveal differences between athletes of differing skill levels. The purpose of this study was to examine trunk and lower extremity (LE) single joint kinematic variability and inter-segmental coordination variability in dancers and non-dancers during bipedal vertical dance jumps (sautés). Twenty healthy females, ten with no formal dance training and ten professional dancers, performed 20 consecutive sautés. Single joint kinematic variability was assessed using mean standard deviation of angular displacement, and inter-segmental coordination variability was assessed using angular deviation of the coupling angle between segments. Within the context of the standard error …

The Influence Of Hip Strength On Lower-Limb, Pelvis, And Trunk Kinematics And Coordination Patterns During Walking And Hopping In Healthy Women, Jo Armour Smith, John M. Popovich, Kornelia Kulig

Physical Therapy Faculty Articles and Research

Study Design

Cross-sectional laboratory study.

Objectives

To compare peak lower-limb, pelvis, and trunk kinematics and interjoint and intersegmental coordination in women with strong and weak hip muscle performance.

Background

Persons with lower extremity musculoskeletal disorders often demonstrate a combination of weak hip musculature and altered kinematics during weight-bearing dynamic tasks. However, the association between hip strength and kinematics independent of pathology or pain is unclear.

Methods

Peak hip extensor and abductor torques were measured in 150 healthy young women. Of these, 10 fit the criteria for the strong group and 9 for the weak group, representing those with the strongest …

Agreement In Gait Speed From Smartphone And Stopwatch For Five Meter Walk In Laboratory And Clinical Environments, Rahul Soangra, Thurmon E. Lockhart

Physical Therapy Faculty Articles and Research

Gait speed is suggested as an independent predictor of post-operative morbidity and mortality in elderly cardiovascular disease (CVD) patients. Society of thoracic surgeons has recently classified gait speed as the only important indicator of health for CVD patients. It has been seen that patients with slow gait speed above 70 years of age, taking more than 6 seconds to walk 5 meters are particularly at high risk for adverse outcomes. Twelve young participants walked in their self-selected, slow and fast speed with five reflective markers at sternum and heels and toes of both feet in laboratory environment. A smartphone was …

Age-Related Modifications To The Magnitude And Periodicity Of Neuromuscular Noise, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

Background: Evaluation of task related outcomes within geriatric and fall-prone populations is essential not only for identification of neuromuscular deficits, but also for effective implementation of fall prevention strategies. As most tasks and activities of daily living are performed at submaximal force levels, restoration of muscle strength often does not produce the expected benefit in functional capacity. However, it is known that muscular control plays a key role in the performance of functional tasks, but it remains unclear to what degree muscular control and the associated neuromuscular noise (NmN) is age-related, particularly in the lower-extremities.

Objectives: The aim of this …

Applying Principles Of Motor Learning And Control To Upper Extremity Rehabilitation, Lisa M. Muratori, Eric M. Lamberg, Lori Quinn, Susan V. Duff

Physical Therapy Faculty Articles and Research

The purpose of this article is to provide a brief review of the principles of motor control and learning. Different models of motor control from historical to contemporary are presented with emphasis on the Systems model. Concepts of motor learning including skill acquisition, measurement of learning, and methods to promote skill acquisition by examining the many facets of practice scheduling and use of feedback are provided. A fictional client case is introduced and threaded throughout the article to facilitate understanding of these concepts and how they can be applied to clinical practice.