Musculoskeletal System Commons^™

Multifunctional Hydroxyapatite And Poly(D,L-Lactide-Co-Glycolide) Nanoparticles For The Local Delivery Of Cholecalciferol, Nenad Ignjatović, Vuk Uskoković, Zorica Ajduković, Dragan Uskoković

Pharmacy Faculty Articles and Research

Cholecalciferol, vitamin D3, plays an important role in bone metabolism by regulating extracellular levels of calcium. Presented here is a study on the effects of the local delivery of cholecalciferol (D3) using nanoparticulate carriers composed of hydroxyapatite (HAp) and poly(D,L-lactide-co-glycolide) (PLGA). Multifunctional nanoparticulate HAp-based powders were prepared for the purpose of: (a) either fast or sustained, local delivery of cholecalciferol, and (b) the secondary, osteoconductive and defect-filling effect of the carrier itself. Two types of HAp-based powders with particles of narrowly dispersed sizes in the nano range were prepared and tested in this study: HAp nanoparticles as direct cholecalciferol delivery …

Assessment Of Postural Stability Using Inertial Measurement Unit On Inclined Surfaces In Healthy Adults, Chris Frames, Rahul Soangra, Thurmon Lockhart

Physical Therapy Faculty Articles and Research

Fatal and nonfatal falls in the construction domain remain a significant issue in today’s workforce. The roofing industry in particular, annually ranks amongst the highest in all industries. Exposure to an inclined surface, such as an inclined roof surface, has been reported to have adverse effects on postural stability. The purpose of this preliminary study was to investigate the intra-individual differences in stability parameters on both inclined and level surfaces. Postural Stability (PS) and Limit of Stability (LOS) were assessed in seven healthy subjects (aged 25-35 years) on inclined and level surfaces using embedded force plates and an Inertial Measurement …

Comparison Of Intra Individual Physiological Sway Complexity From Force Plate And Inertial Measurement Unit, Rahul Soangra, Thurmon E. Lockhart

Physical Therapy Faculty Articles and Research

Center of Pressure (COP) is a clinical measure to investigate the effect of sensory input disturbances on postural stability in healthy, old population as well in people suffering from neuromuscular disease. Increased center of pressure velocity and sway area are interpreted as decreased stability or poor balance and are associated with fall risk. Body mounted inertial sensors have shown great promise as an easily implemented clinical measure of balance. The aim of the present study is to investigate if force plate and accelerometer measurements provide similar physiological information when approximate entropy (ApEn) are valuated from the time series. Seven Young …

Nanoparticles Of Cobalt-Substituted Hydroxyapatite In Regeneration Of Mandibular Osteoporotic Bones, Nenad Ignjatović, Zorica Ajduković, Vojin Savić, Stevo Najman, Dragan Mihailović, Perica Vasilijević, Zoran Stojanović, Vuk Uskoković, Dragab Uskoković

Pharmacy Faculty Articles and Research

Indications exist that paramagnetic calcium phosphates may be able to promote regeneration of bone faster than their regular, diamagnetic counterparts. In this study, analyzed was the influence of paramagnetic cobalt-substituted hydroxyapatite nanoparticles on osteoporotic alveolar bone regeneration in rats. Simultaneously, biocompatibility of the material was tested in vitro, on osteoblastic MC3T3-E1 and epithelial Caco-2 cells in culture. The material was shown to be biocompatible and nontoxic when added to epithelial monolayers in vitro, while it caused a substantial decrease in the cell viability as well as deformation of the cytoskeleton and cell morphology when incubated with the osteoblastic …

Wavelet Based Automated Postural Event Detection And Activity Classification With Single Imu (Tempo), Thurmon E. Lockhart, Rahul Soangra, Jian Zhang, Xuefang Wu

Physical Therapy Faculty Articles and Research

Mobility characteristics associated with activity of daily living such as sitting down, lying down, rising up, and walking are considered to be important in maintaining functional independence and healthy life style especially for the growing elderly population. Characteristics of postural transitions such as sit-to-stand are widely used by clinicians as a physical indicator of health, and walking is used as an important mobility assessment tool. Many tools have been developed to assist in the assessment of functional levels and to detect a person’s activities during daily life. These include questionnaires, observation, diaries, kinetic and kinematic systems, and validated functional tests. …

Extreme Levels Of Noise Constitute A Key Neuromuscular Deficit In The Elderly, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

Fluctuations during isometric force production tasks occur due to the inability of musculature to generate purely constant submaximal forces and are considered to be an estimation of neuromuscular noise. The human sensori-motor system regulates complex interactions between multiple afferent and efferent systems, which results in variability during functional task performance. Since muscles are the only active component of the motor system, it therefore seems reasonable that neuromuscular noise plays a key role in governing variability during both standing and walking. Seventy elderly women (including 34 fallers) performed multiple repetitions of isometric force production, quiet standing and walking tasks. No relationship …

Determination Of Stabilogram Diffusion Analysis Coefficients And Invariant Density Analysis Parameters To Understand Postural Stability Associated With Standing On Anti-Fatigue Mats, Rahul Soangra, Thurmon E. Lockhart

Physical Therapy Faculty Articles and Research

Prolonged standing has been associated with loss of balance, onset of low back pain symptoms and development of fatigue in lower extremity muscles in working populations. Although so far, it is unknown how individuals’ postural stability is affected by standing on rigid versus cushioned platform but many industries are opting for anti-fatigue mats at workstations to reduce fall and injury related socio-economic cost. The goal of this study is to test SATECH's anti-fatigue mat for its effects on postural stability. A pilot test with seven healthy subjects (25–35 years old) has been conducted with a force plate to obtain kinetics …

Non-Invasive Fall Risk Assessment In Community Dwelling Elderly With Wireless Inertial Measurement Units, Thurmon E. Lockhart, Han T. Yeoh, Rahul Soangra, Manutchanok Jongprasithporn, Jian Zhang, Xuefang Wu, Arka Ghosh

Physical Therapy Faculty Articles and Research

Falls are among the most serious accidents among the elderly leading to increased injuries, reduced functioning and mortality. In 2009, about 2.2 million nonfatal fall injuries were reported among the elderly population (CDC, 2010). In this study, eleven community dwelling elderly (aged 65-84 years) participated in fall risk assessment camp at sterling senior center organized by Northern Virginia Fall Prevention Coalition (NVFPC). Three custom made wireless inertial measurement units (IMUs) were attached on trunk and both shanks. All participants performed postural and locomotor tasks such as sit-to-stand (STS) and timed up and go (TUG). Temporal and kinematic parameters were obtained. …

Investigation Into The Functional Mobility Difference Between Obese And Non-Obese Elderly, Xuefang Wu, Han T. Yeoh, Rahul Soangra, Thurmon Lockhart

Physical Therapy Faculty Articles and Research

Obese aging population is increasing in the United States, and obese elderly experience fall twice as frequent as their lean counterparts. However, the mechanisms of older obese adults fall are still not clear. It is not known whether the obese elderly has more functional mobility impairments than their lean counterparts, and consequently have increased risks of falls. It was hypothesized that obese elderly have more functional mobility impairments compared with their healthy weight counterparts. Six lean and six obese community-dwelling elderly participated in the study. “Timed up & go” test was used to quantify the functional mobility for both lean …

A Comparative Study For Performance Evaluation Of Sit-To-Stand Task With Body Worn Sensor And Existing Laboratory Methods, Rahul Soangra, Thurmon E. Lockhart

Physical Therapy Faculty Articles and Research

Human movement such as sit-to-stand (STS) is one of the most fundamental and essential movement among daily living activities. Elderly who are unable to stand are severely limited in daily activities and rely on others for their care. In the coming next two decades about 20% of US population will be above the age of 65 years, and considering ever-increasing elderly population and health care expenses, the rehabilitation of functionally limited elderly is becoming a topic of greater concern. Clinically STS movement is looked upon with great interest, such as its analysis is meaningful in order to evaluate motor control …

Pressure Distribution Over The Palm Region During Forward Falls On The Outstretched Hands, Woochol J. Choi, Stephen N. Robinovitch

Physical Therapy Faculty Articles and Research

Falls on the outstretched hands are the cause of over 90% of wrist fractures, yet little is known about bone loading during this event. We tested how the magnitude and distribution of pressure over the palm region during a forward fall is affected by foam padding (simulating a glove) and arm configuration, and by the faller’s body mass index (BMI) and thickness of soft tissues over the palm region.

Thirteen young women with high (n=7) or low (n=6) BMI participated in a “torso release experiment” that simulated falling on both outstretched hands with the arm inclined either at 20° or …

An Approach For Identifying Gait Events Using Wavelet Denoising Technique And Single Wireless Imu, Rahul Soangra, Thurmon Lockhart, Nathalie Van De Berge

Physical Therapy Faculty Articles and Research

A new approach is proposed to identify gait events in non-laboratory environments with a single inertial measurement unit (IMU) embedded inside shoe. The aim of our work is to develop a useful clinical tool for monitoring individuals walking disability and detect specific pathological gait patterns. Temporal parameters of gait are determined by classification of accelerations and angular velocities. Wavelets denoising of IMU signals allows for an important amount of information that is exploited in different manners for event identification. It was found that wavelet denoising enhanced specific turning points which could effectively identify gait events. The method is verified by …

Nanosized Hydroxyapatite And Other Calcium Phosphates: Chemistry Of Formation And Application As Drug And Gene Delivery Agents, Vuk Uskoković, Dragan Uskoković

Pharmacy Faculty Articles and Research

The first part of this review looks at the fundamental properties of hydroxyapatite (HAP), the basic mineral constituent of mammalian hard tissues, including the physicochemical features that govern its formation by precipitation. A special emphasis is placed on the analysis of qualities of different methods of synthesis and of the phase transformations intrinsic to the formation of HAP following precipitation from aqueous solutions. This serves as an introduction to the second part and the main subject of this review, which relates to the discourse regarding the prospects of fabrication of ultrafine, nanosized particles based on calcium phosphate carriers with various …

Pressure Distribution Over The Palm During Falls On The Outstretched Hands, Woochol J. Choi, Stephen N. Robinovitch

Physical Therapy Faculty Articles and Research

"Over 90% of wrist fractures are caused by falls on the outstretched hands (Palvanen et al., Osteoporos Int, 2000). Along with bone strength, fracture risk depends on the magnitude and distribution of force to soft and hard tissues during impact. In the current study, we examined how pressure distribution over the palm during a fall is affected by impact configuration, body mass index (BMI), palmer soft tissue thickness, and a 5 mm thick foam pad (simulating a protective glove)."

Different Training Volumes Yield Equivalent Increases In Bmd, R. A. Pierce, L. C. Lee, C. P. Ahles, S. M. Shdo, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The purpose of this study was to determine if an exercise threshold existed in stimulating an elevation in bone mineral density (BMD), via resistance training, during the growth period in male rats. 27 male rats were randomly divided into Control (Con, n = 9), 3 ladder climb resistance trained group (3LC, n = 9), and 6 ladder climb resistance trained group (6LC, n = 9). The 3LC and 6LC groups were conditioned to climb a vertical ladder with weights appended to their tail 3 days/wk for a total of 6 wks, but the 6LC group performed significantly more work than …

Equal Bmd After Daily Or Triweekly Exercise In Growing Rats, B. D. Kayser, J. K. Godfrey, R. M. Cunningham, R. A. Pierce, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The purpose of this study was to examine the efficacy of continuous resistance training (3 days/wk) compared to interrupted resistance training where 20-24 h separated an exercise bout (i.e. 6 days/wk) for enhancing bone mineral density (BMD) in growing male rats. The total volume of work performed per week between the two resistance training programs was equivalent by design. Young male rats were randomly divided into Control (Con, n = 9), 3 days/wk resistance trained group (RT3, n = 9), and 6 days/wk resistance trained group (RT6, n = 9). The RT3 and RT6 groups were conditioned to climb a …

Portable, Non-Invasive Fall Risk Assessment In End Stage Renal Disease Patients On Hemodialysis, Thurmon Lockhart, Adam T. Barth, Xiaoyue Zhang, Rahul Soangra, Emaad Abdel-Rahman, John Lach

Physical Therapy Faculty Articles and Research

Patients with end stage renal diseases (ESRD) on hemodialysis (HD) have high morbidity and mortality due to multiple causes, one of which is dramatically higher fall rates than the general population. The mobility mechanisms that contribute to falls in this population must be understood if adequate interventions for fall prevention are to be achieved. This study utilizes emerging noninvasive, portable gait, posture, strength, and stability assessment technologies to extract various mobility parameters that research has shown to be predictive of fall risk in the general population. As part of an ongoing human subjects study, mobility measures such as postural and …

The Impact Of Left Hemisphere Stroke On Force Control With Familiar And Novel Objects: Neuroanatomic Substrates And Relationship To Apraxia, Amanda M. Dawson, Laura J. Buxbaum, Susan V. Duff

Physical Therapy Faculty Articles and Research

Fingertip force scaling for lifting objects frequently occurs in anticipation of finger contact. An ongoing question concerns the types of memories that are used to inform predictive control. Object-specific information such as weight may be stored and retrieved when previously encountered objects are lifted again. Alternatively, visual size and shape cues may provide estimates of object density each time objects are encountered. We reasoned that differences in performance with familiar versus novel objects would provide support for the former possibility. Anticipatory force production with both familiar and novel objects was assessed in six left hemisphere stroke patients, two of whom …

Performance Of A Hip Protector Depends On Its Position During A Fall, Woochol J. Choi, Joaquin A. Hoffer, Stephen N. Robinovitch

Physical Therapy Faculty Articles and Research

"Hip protectors are designed to attenuate and redistribute the force applied to the hip region during a fall, and thereby reduce risk for hip fracture [1]. However, little information exists on the effectiveness of hip protectors in achieving these goals, and how this is altered by displacement of the hip protector relative to the greater trochanter (GT). In the current study, we tested these issues."

Gastrocnemius-Soleus Muscle Tendon Unit Changes Over The First 12 Weeks Of Adjusted Age In Infants Born Preterm, Marybeth Grant-Beuttler, Robert J. Palisano, Debra P. Miller, Barbara Reddien Wagner, Carolyn B. Heriza, Patricia A. Shewokis

Physical Therapy Faculty Articles and Research

Background and Purpose: Differences in the gastrocnemius-soleus muscle and tendon have been documented shortly after birth in infants born preterm compared with infants born at term. Knowledge of muscle tendon unit lengths at term age to 12 weeks of age in infants born preterm may be useful in understanding motor development.

Participants and Method: Gastrocnemius-soleus muscle tendon unit lengths were compared at term age, at 6 weeks of age, and at 12 weeks of age (preterm adjusted age) in 20 infants born full term and 22 infants born preterm.

Results: Significant differences were found between the 2 groups on taut …

Author Response To Invited Commentary By Heathcock [Commentary For: Gastrocnemius/Soleus Muscle Tendon Unit Changes Over The First 12 Weeks Of Adjusted Age In Infants Born Preterm], Marybeth Grant-Beuttler, Robert J. Palisano, Debra P. Miller, Barbara Reddien Wagner, Carolyn B. Heriza, Patricia A. Shewokis

Physical Therapy Faculty Articles and Research

"We thank Heathcock for taking the time to write her commentaryregarding our study. Her comments are interesting, and our subsequent investigation into these ideas has led us to uncover some enlightening evidence in relation to the topics raised in the commentary. We will attempt to review each of the topics raised and the evidence associated with these topics."

Interrupted Resistance Training And Bmd In Growing Rats, J. K. Godfrey, B. D. Kayser, G. V. Gomez, Jason Bennett, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A resistance training program, where the exercise was uninterrupted (UT, i.e. continuous repetitions) was compared against another resistance training program where the exercise was interrupted (IT, i.e. 2 exercise sessions during a training day) for enhancing bone modeling and bone mineral density (BMD) in maturating animals. The total volume of work performed between the two resistance training programs was equivalent by design. Young male rats (similar to 8 weeks old) were randomly divided into Control (Con, n = 8), UT (n = 8) and IT (n = 7) resistance trained groups. The UT and IT groups were conditioned to climb …

Resistance Training And Bone Mineral Density During Growth, M. Z. Smith, B. M. Goettsch, R. D. Van Ramshorst, J. A. O'Brien, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This study examined the efficacy of two different resistance training programs in enhancing bone modeling and bone mineral density (BMD) in maturating rats. One exercise mode involved lifting a lighter weight with more repetitions (LI), while the other regimen involved lifting a heavier weight with fewer repetitions (HI) where the total volume of work between exercise programs was equivalent by design. Twenty-three male rats were randomly divided into control (Con, n = 8), LI (n = 7), and HI (n = 8) groups. The LI and HI groups were conditioned to climb a vertical ladder with weights appended to their …

Interrupted Vs. Uninterrupted Training On Bmd During Growth, B. M. Goettsch, M. Z. Smith, J. A. O'Brien, G. V. Gomez, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This study compared a resistance training program where the exercise was uninterrupted (UT, i.e., continuous repetitions) against a resistance training program where the exercise was interrupted (IT, i.e., 3 exercise sessions during a training day) for enhancing bone modeling and bone mineral density (BMD) in maturating animals. The total volume of work performed between the two resistance training programs was equivalent by design. 24 young male rats were randomly divided into Control (Con, n = 8), UT (n = 8) and IT (n=8) resistance trained groups. The UT and IT groups were conditioned to climb a vertical ladder with weights …

Making Some Bones About It, Roxanne Greitz Miller, Frank Frisch

Education Faculty Articles and Research

The article discusses the importance of bone tissue to human beings and the ways to help students to understand its functions. The bone tissue forms the human skeleton to produce varied motions such as walking and talking. In addition, it protects the vital organs of a person and contributes the development of blood. The bone is composed of bone matrix, a dense material occupied by calcium and potassium salts. The matrix comprises several cell types including osteoblasts, osteocytes and osteoclasts. According to the author, a continuous influx of new calcium is necessary because of the constant remodeling of bone tissue. …

Influence Of A Functional Knee Brace And Exercise On Lower Extremity Kinematics During Jogging, Brian M. Campbell, Daniel Cipriani, James A. Yaggie

Physical Therapy Faculty Articles and Research

ABSTRACT Context: Functional knee braces (FKB) are used prophylactically and in rehabilitation to aide in the functional stability of the knee joint. Objective: To determine if alterations in sagittal plane lower extremity kinematics remain evident throughout a one hour period in healthy individuals. Design: 2X5 repeated measures design. Setting: Biomechanics Laboratory. Subjects: Twenty subjects (14 male and 6 female, mean age 26.5±7 yrs; height 172.4±13 cm; weight 78.6±9 kg), separated into braced (B) and no brace (NB) groups. Intervention: A one-hour exercise program divided into three 20 minute increments. Main Outcome Measures: Synchronized three-dimensional …

The Role Of Lower Leg Muscle Activity In Blood Pressure Maintenance Of Older Adults, Michelle M. Masterson, Amy L. Morgan, Christine E. Multer, Daniel Cipriani

Physical Therapy Faculty Articles and Research

Purpose. Age-associated muscle weakness, postural instability, and orthostatic hypotension have been identified as contributing factors to falls , but the relationships among them are not clear. Therefore, the purpose of this study, a two-way factorial design, was to investigate the differences in lower extremity (LE) muscle activity, blood pressure (BP), and heart rate (HR) between young and older individuals in an upright position. Methods. Ten young males (20-24 yrs.) and 10 older males (65-82 yrs.) stood for 15 minutes while BP, HR, and LE electromyography (EMG) were recorded at one minute intervals . A two-way ANOVA was used …

Human Cytomegalovirus Chemokine Receptor Us28-Induced Smooth Muscle Cell Migration Is Mediated By Focal Adhesion Kinase And Src, Daniel N. Streblow, Jennifer Totonchy, Patsy Smith, Ryan Melnychuk, Laurel Hall, Dora Pancheva, Martine Smit, Paola Casarosa, David D. Schlaepfer, Jay A. Nelson

Pharmacy Faculty Articles and Research

The human cytomegalovirus-encoded chemokine receptor US28 induces arterial smooth muscle cell (SMC) migration; however, the underlying mechanisms involved in this process are unclear. We have previously shown that US28-mediated SMC migration occurs by a ligand-dependent process that is sensitive to proteintyrosine kinase inhibitors. We demonstrate here that US28 signals through the non-receptor protein-tyrosine kinases Src and focal adhesion kinase (FAK) and that this activity is necessary for US28-mediated SMC migration. In the presence of RANTES (regulated on activation normal T cell expressed and secreted), US28 stimulates the production of a FAK Src kinase complex. Interestingly, Src co-immunoprecipitates with US28 in …

Synthesis And Characterization Of Hydroxyapatite-Collagen Biocomposite Materials, Vuk Uskoković, Nenad Ignjatović, Nadejda Petranović

Pharmacy Faculty Articles and Research

Hydroxyapatite-collagen composite is a prosperous biomaterial in reconstructive surgery for the reparation of defects within human hard tissue. Within this research, three-dimensional blocks of HAp/collagen composite biomaterial were synthesized by homogenizing the HAp/collagen mixture by cold and hot (T=60oC) pressing (P=49 MPa). The changes in the system were followed by using thermal analysis (DSC & TGA), FT-IR spectroscopy and scanning electron microscopy (SEM). The identification and kinetic analysis of appearing phase transition were done. FT-IR spectrum of the biocomposite shows that neither cold nor hot pressing had significant influence on the individual components of the composite. SEM of the fracture …

Safe At The Shoulder, Daniel Cipriani

Physical Therapy Faculty Articles and Research

The key to preventing shoulder injuries is understanding the anatomy of the shoulder complex and how the body's other muscles affect the throwing motion