Effects of Statins on Skeletal Muscle: A Perspective for Physical Therapists

Hyperlipidemia, also known as high blood cholesterol, is a cardiovascular health risk that affects more than one third of adults in the United States. Statins are commonly prescribed and successful lipid-lowering medications that reduce the risks associated with cardiovascular disease. The side effects most commonly associated with statin use involve muscle cramping, soreness, fatigue, weakness, and, in rare cases, rapid muscle breakdown that can lead to death. Often, these side effects can become apparent during or after strenuous bouts of exercise. Although the mechanisms by which statins affect muscle performance are not entirely understood, recent research has identified some common causative factors. As musculoskeletal and exercise specialists, physical therapists have a unique opportunity to identify adverse effects related to statin use. The purposes of this perspective article are: (1) to review the metabolism and mechanisms of actions of statins, (2) to discuss the effects of statins on skeletal muscle function, (3) to detail the clinical presentation of statin-induced myopathies, (4) to outline the testing used to diagnose statin-induced myopathies, and (5) to introduce a role for the physical therapist for the screening and detection of suspected statin-induced skeletal muscle myopathy.

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The myotendinous junction marker collagen XXII enables zebrafish postural control learning and optimal swimming performance through its force transmission activity

10.1101/2021.07.14.452354 ◽

2021 ◽

Author(s):

Marilyne Malbouyres ◽

Alexandre Guiraud ◽

Christel Lefrancois ◽

Melanie Salamito ◽

Pauline Nauroy ◽

...

Keyword(s):

Skeletal Muscle ◽

Swimming Performance ◽

Muscle Performance ◽

Myotendinous Junction ◽

Force Transmission ◽

Skeletal Muscle Function ◽

Gene Ablation ◽

Class 1 ◽

Control Learning ◽

Degrees Of Severity

Although the myotendinous junction (MTJ) is essential for skeletal muscle integrity, its contribution to skeletal muscle function remains largely unknown. Here, we show that CRISPR-Cas9-mediated gene ablation of the MTJ marker col22a1 in zebrafish identifies two distinctive phenotypic classes: class 1 individuals reach adulthood with no overt muscle phenotype while class 2 display severe movement impairment and eventually dye before metamorphosis. Yet mutants that are unequally affected are all found to display defective force transmission attributed to a loss of ultrastructural integrity of the MTJ and myosepta, though with distinct degrees of severity. The behavior-related consequences of the resulting muscle weakness similarly reveal variable phenotypic expressivity. Movement impairment at the critical stage of swimming postural learning eventually causes class 2 larval death by compromising food intake while intensive exercise is required to uncover a decline in muscle performance in class 1 adults. By confronting MTJ gene expression compensation and structural, functional and behavioral insights of MTJ dysfunction, our work unravels variable expressivity of col22a1 mutant phenotype. This study also underscores COL22A1 as a candidate gene for myopathies associated with dysfunctional force transmission and anticipates a phenotypically heterogeneous disease.

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Action of GH on skeletal muscle function: molecular and metabolic mechanisms

Journal of Molecular Endocrinology ◽

10.1530/jme-13-0208 ◽

2013 ◽

Vol 52 (1) ◽

pp. R107-R123 ◽

Cited By ~ 48

Author(s):

Viral Chikani ◽

Ken K Y Ho

Keyword(s):

Skeletal Muscle ◽

Muscle Function ◽

The Elderly ◽

Energy System ◽

Muscle Performance ◽

Whole Body ◽

Target Tissue ◽

Dependent Manner ◽

Skeletal Muscle Function ◽

Body Protein

Skeletal muscle is a target tissue of GH. Based on its anabolic properties, it is widely accepted that GH enhances muscle performance in sports and muscle function in the elderly. This paper critically reviews information on the effects of GH on muscle function covering structure, protein metabolism, the role of IGF1 mediation, bioenergetics and performance drawn from molecular, cellular and physiological studies on animals and humans. GH increases muscle strength by enhancing muscle mass without affecting contractile force or fibre composition type. GH stimulates whole-body protein accretion with protein synthesis occurring in muscular and extra-muscular sites. The energy required to power muscle function is derived from a continuum of anaerobic and aerobic sources. Molecular and functional studies provide evidence that GH stimulates the anaerobic and suppresses the aerobic energy system, in turn affecting power-based functional measures in a time-dependent manner. GH exerts complex multi-system effects on skeletal muscle function in part mediated by the IGF system.

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Video-Based Motion Analysis Use: A National Survey of Orthopedic Physical Therapists

Physical Therapy ◽

10.1093/ptj/pzaa125 ◽

2020 ◽

Vol 100 (10) ◽

pp. 1759-1770

Author(s):

Craig P Hensley ◽

Devyn Millican ◽

Nida Hamilton ◽

Amy Yang ◽

Jungwha Lee ◽

...

Keyword(s):

United States ◽

Clinical Practice ◽

Treatment Outcomes ◽

Motion Analysis ◽

Online Survey ◽

Physical Therapists ◽

Physical Therapist ◽

Reliability And Validity ◽

The United States ◽

Future Research

Abstract Objectives Motion analysis is performed by physical therapists to assess and improve movement. Two-dimensional video-based motion analysis (VBMA) is available for smartphones/tablets and requires little to no equipment or cost. Research on VBMA use in clinical practice is limited. The purpose of this study was to examine the current use of VBMA in orthopedic physical therapist practice. Methods Members of the Academy of Orthopaedic Physical Therapy completed an online survey. Questions examined frequency of VBMA use, reasons for use, facilitators/barriers, device/apps used, practice patterns, other certificates/degrees, and demographic information. Results Among the final analysis sample of 477 respondents, 228 (47.8%) use VBMA. Of 228 VBMA users, 91.2% reported using it for ≤25% of their caseload, and 57.9% reported using their personal device to capture movement. Reasons for using VBMA included visual feedback for patient education (91.7%), analysis of movement (91.2%), and assessment of progress (51.8%). Barriers to use included lack of device/equipment (48.8%), lack of space (48.6%), and time restraint (32.1%). Those with ≤20 years of clinical experience (odds ratio [OR] = 1.83, 95% CI = 1.21–2.76), residency training (OR = 2.49, 95% CI = 1.14–5.43), and fellowship training (OR = 2.97, 95% CI = 1.32–6.66), and those from the West region of the United States (OR = 1.66, 95% CI = 1.07–2.56) were more likely to use VBMA. Conclusions More than 50% of surveyed orthopedic physical therapists do not use VBMA in clinical practice. Future research should be directed toward assessing reliability and validity of VBMA use by smartphones, tablets, and apps and examining whether VBMA use enhances treatment outcomes. Data security, patient confidentiality, and integration into the electronic medical record should be addressed. Impact This study is the first to our knowledge to describe the use of VBMA in orthopedic physical therapist practice in the United States. It is the first step in understanding how VBMA is used and might be used to enhance clinical assessment and treatment outcomes.

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The First Year of Practice: An Investigation of the Professional Learning and Development of Promising Novice Physical Therapists

Physical Therapy ◽

10.2522/ptj.20100078 ◽

2010 ◽

Vol 90 (12) ◽

pp. 1758-1773 ◽

Cited By ~ 53

Author(s):

Lisa L. Black ◽

Gail M. Jensen ◽

Elizabeth Mostrom ◽

Jan Perkins ◽

Pamela D. Ritzline ◽

...

Keyword(s):

Identity Formation ◽

Professional Learning ◽

Clinical Education ◽

Physical Therapists ◽

Physical Therapist ◽

The United States ◽

First Year ◽

Clinical Environment ◽

Learning And Development ◽

New Graduates

Background The goal in studying expertise is not merely to describe ways in which experts excel but also to understand how experts develop in order to better facilitate the development of novices. The study of novice progression helps us to understand what successful versus unsuccessful learning looks like. This understanding is critical, as autonomous practice places increased demands for advanced clinical judgments and the ability to assume professional responsibilities. Objectives The purpose of this study was to explore the experiences, learning, and development of promising novice therapists throughout their first year of practice in the United States. Design and Methods A longitudinal, multiple-site qualitative case study method was used for within-case and across-case analysis. A purposive sample of 11 promising new graduates from 4 physical therapist education programs participated. Investigators followed the graduates throughout their first year of practice. Data sources included: (1) semistructured interviews conducted at baseline and every 3 months thereafter for 1 year, (2) reflective journals completed at regular intervals, and (3) review of academic and clinical education records and résumés. Results Four themes emerged: (1) the clinical environment influenced the novice physical therapists' performance, (2) participants learned through experience and social interaction and learning was primarily directed toward self, (3) growing confidence was directly related to developing communication skills, and (4) therapists were engaged in professional identity formation and role transitions. Conclusions The findings suggest there are common experiences and themes that emerge as novice physical therapists develop. Although research has been conducted on expertise in physical therapy, few longitudinal investigations have explored the development of therapists across transitions from graduate to novice to expert practitioner. This study explored and described the learning and development of graduates during their first year of practice.

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Time-restricted feeding promotes skeletal muscle function in diet- and genetic-induced obesity through shared and unique pathways

10.21203/rs.3.rs-828135/v1 ◽

2021 ◽

Author(s):

Christopher Livelo ◽

Yiming Guo ◽

Shweta Varshney ◽

Farah Abou Daya ◽

Hiep Le ◽

...

Keyword(s):

Skeletal Muscle ◽

Muscle Function ◽

De Novo ◽

Tca Cycle ◽

Glycogen Metabolism ◽

Fruit Fly ◽

Muscle Performance ◽

Restricted Feeding ◽

Skeletal Muscle Function ◽

Atp Levels

Abstract Obesity caused by genetic predisposition, a lifestyle of calorie-dense diets and/or circadian disruption can result in complications including metabolic syndrome, cardiovascular disease, and compromised muscle function. By employing time-restricted feeding (TRF), where daily feeding was limited to 12 hours during the day, we observed improved skeletal muscle function compared to ad libitum feeding (ALF). This was observed in both diet-induced obesity (DIO) and genetic-induced obesity (GIO) in a Drosophila melanogaster (fruit fly) model. We evaluated the mechanistic basis of TRF-mediated benefits by utilizing muscle transcriptomic data of indirect flight muscle (IFM) followed by genetic validations, cytological and biochemical evidences. Significant upregulation of glycine N methyltransferase (Gnmt), sarcosine dehydrogenase (Sardh), CG5955 and downregulation of diacylglycerol o-acyltransferase 2 (Dgat2) were commonly induced by TRF intervention under both obese conditions. Moreover, genetic inhibition of Gnmt, Sardh and CG5955 leads to skeletal muscle dysfunction, aberrant lipid accumulation and loss of TRF-mediated benefits. However, skeletal muscle-specific knockdown (KD) of Dgat2 retained muscle function during aging, a result that mimics TRF-mediated benefits. Furthermore, de novo purine biosynthesis appeared to be upregulated specifically in the DIO model under TRF which led to increased ATP levels resulting in improved muscle performance. Additionally, genes associated with AMP kinase (AMPK) signaling, glycogen metabolism, glycolysis, tricarboxylic acid (TCA) cycle and electron transport chain (ETC) signaling were specifically upregulated in GIO model under TRF. TRF mediated benefits in GIO via activation of AMPK, which led to increased ATP levels. Altogether, we identify the shared and distinct pathways in the regulation of muscle function under TRF, which may aid further research and alternative therapeutic avenues that focus on combating comorbidities linked with obesity.

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Referral for Imaging in Physical Therapist Practice: Key Recommendations for Successful Implementation

Physical Therapy ◽

10.1093/ptj/pzab013 ◽

2021 ◽

Author(s):

Aaron Paul Keil ◽

Charles Hazle ◽

Amma Maurer ◽

Connie Kittleson ◽

Daniel Watson ◽

...

Keyword(s):

Physical Therapy ◽

Diagnostic Imaging ◽

Physical Therapists ◽

Physical Therapist ◽

The United States ◽

Successful Implementation ◽

Program Accreditation ◽

Therapy Program ◽

Normative Practice ◽

American Physical

Abstract In recent years, the use of diagnostic imaging in physical therapist practice in the United States (US) has gained considerable interest. In several countries around the world and in the US military, patient direct referral for diagnostic imaging has been considered normative practice for decades. US physical therapy program accreditation standards now stipulate that diagnostic imaging content must be included in physical therapist educational curricula. The American Physical Therapy Association (APTA) has made efforts to pursue practice authority for imaging referral. A recent review of state practice acts and other statutory language concluded that many states have no prohibitions against physical therapists referring for imaging studies. Additionally, physical therapists can now pursue certification as musculoskeletal sonographers. In light of these advances, and with a growing number of PTs serving patients who have not yet seen another healthcare provider, it may be helpful for those who have been actively involved in the use of imaging in PT practice to provide their collective recommendations to serve as a guideline to those interested in incorporating this practice privilege. The purpose of this perspective article is to provide an overview of the key elements necessary for effective implementation of referral for imaging in physical therapist practice while emphasizing the cornerstone of effective communication.

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We Don’t Know our Own Strength: A Survey of Strength Training Attitudes, Behaviors and Knowledge in Physical Therapists and Physical Therapist Students

Physical Therapy ◽

10.1093/ptj/pzab204 ◽

2021 ◽

Author(s):

Reed Handlery ◽

Emma Shover ◽

Thavi Chhoun ◽

Lauren Durant ◽

Kaci Handlery ◽

...

Keyword(s):

Physical Therapy ◽

Strength Training ◽

Professional Education ◽

Physical Therapists ◽

Physical Therapist ◽

The United States ◽

Physical Therapy Students ◽

Physical Therapy Education ◽

Education Participation ◽

Therapy Education

Abstract Objective Strength training is frequently utilized by physical therapists; however, there has been discussion about whether physical therapists utilize strength training adequately. The purpose of this study was to describe and compare the strength training attitudes, behaviors, and knowledge of physical therapists and physical therapy students and to determine how participant characteristics influenced knowledge scores. Methods An anonymous survey was created in 3 rounds. For round 1, researchers used textbooks to create items assessing demographics, attitudes, behaviors, and knowledge regarding strength training. Rounds 2 and 3 consisted of feedback from 7 content experts until 80% consensus was reached; items were added, removed, or edited based on feedback. The final survey was distributed through social media, list servs, and email, targeting physical therapists and students based in the United States. Response frequencies for all items were reported. Overall knowledge scores were calculated by summing correct responses for each item, with a maximum score of 13; scores <70% were considered low. Binomial logistic regression determined which characteristics (demographics, attitudes, or behaviors) influenced whether participants adequately utilized strength training principles (scored ≥70% on knowledge items). Results There were 777 physical therapist and 648 student participants. Nearly 90% of therapists and students reported frequently prescribing strength training. Over 48% of therapists felt their professional education did not prepare them to apply strength training (compared with 24% of students), and 68% believed that strength training is inadequately applied in physical therapy (compared with 40% of students). Sixty-two percent of therapists and 55% of students scored ≥70% for knowledge items. Additional strength training education and regular participation in strength training increased the odds of scoring ≥70% on knowledge items. Conclusions Physical therapists and physical therapy students frequently prescribe strength training, despite similarly low knowledge scores. To increase knowledge, greater emphasis on strength training in professional education, continuing education, participation in strength training, or all 3 is warranted. Impact Strength training is an important intervention used in physical therapy and must be used appropriately to improve the health of patients. According to these findings, strength training education may not currently be optimal, as demonstrated by low knowledge scores by both therapists and students. Further work is needed to determine how knowledge of strength training relates to patient outcomes and also how best to implement strength training in physical therapy education and practice.

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Toward Sensitive Practice: Issues for Physical Therapists Working With Survivors of Childhood Sexual Abuse

Physical Therapy ◽

10.1093/ptj/79.3.248 ◽

1999 ◽

Vol 79 (3) ◽

pp. 248-261 ◽

Cited By ~ 31

Author(s):

Candice L Schachter ◽

Carol A Stalker ◽

Eli Teram

Keyword(s):

Sexual Abuse ◽

Physical Therapy ◽

Childhood Sexual Abuse ◽

Physical Therapists ◽

Physical Therapist ◽

Adult Survivors ◽

The United States ◽

Female Survivors ◽

Semistructured Interviews

Abstract Background and Purpose. The high rates of prevalence of childhood sexual abuse in the United States and Canada suggest that physical therapists work, often unknowingly, with adult survivors of childhood sexual abuse. The purposes of this qualitative study were to explore the reactions of adult female survivors of childhood sexual abuse to physical therapy and to listen to their ideas about how practitioners could be more sensitive to their needs. The dynamics and long-term sequelae of childhood sexual abuse, as currently understood by mental health researchers and as described by the participants, are summarized to provide a context for the findings of this study. Subjects and Methods. Twenty-seven female survivors (aged 19–62 years) participated in semistructured interviews in which they described their reactions to physical therapy. Results. Survivors' reactions to physical therapy, termed “long-term sequelae of abuse that detract from feeling safe in physical therapy,” are reported. Participant-identified suggestions that could contribute to the sense of safety are shared. Conclusions and Discussion. Although the physical therapist cannot change the survivor's history, an appreciation of issues associated with child sexual abuse theoretically can increase clinicians' understanding of survivors' reactions during treatment. We believe that attention by the physical therapist to the client's sense of safety throughout treatment can maximize the benefits of the physical therapy experience for the client who is a survivor. [Schachter CL, Stalker CA, Teram E. Toward sensitive practice: issues for physical therapists working with survivors of childhood sexual abuse.

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Chronic atorvastatin and exercise can partially reverse established skeletal muscle microvasculopathy in metabolic syndrome

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00193.2018 ◽

2018 ◽

Vol 315 (4) ◽

pp. H855-H870 ◽

Cited By ~ 4

Author(s):

Kent A. Lemaster ◽

Stephanie J. Frisbee ◽

Luc Dubois ◽

Nikolaos Tzemos ◽

Fan Wu ◽

...

Keyword(s):

Skeletal Muscle ◽

Metabolic Syndrome ◽

Vascular Function ◽

Microvascular Dysfunction ◽

Vascular Wall ◽

Muscle Performance ◽

Vascular Structure ◽

Skeletal Muscle Function ◽

Targeted Interventions ◽

Wall Stiffness

It has long been known that chronic metabolic disease is associated with a parallel increase in the risk for developing peripheral vascular disease. Although more clinically relevant, our understanding about reversing established vasculopathy is limited compared with our understanding of the mechanisms and development of impaired vascular structure/function under these conditions. Using the 13-wk-old obese Zucker rat (OZR) model of metabolic syndrome, where microvascular dysfunction is sufficiently established to contribute to impaired skeletal muscle function, we imposed a 7-wk intervention of chronic atorvastatin treatment, chronic treadmill exercise, or both. By 20 wk of age, untreated OZRs manifested a diverse vasculopathy that was a central contributor to poor muscle performance, perfusion, and impaired O2 exchange. Atorvastatin or exercise, with the combination being most effective, improved skeletal muscle vascular metabolite profiles (i.e., nitric oxide, PGI2, and thromboxane A2 bioavailability), reactivity, and perfusion distribution at both individual bifurcations and within the entire microvascular network versus responses in untreated OZRs. However, improvements to microvascular structure (i.e., wall mechanics and microvascular density) were less robust. The combination of the above improvements to vascular function with interventions resulted in an improved muscle performance and O2 transport and exchange versus untreated OZRs, especially at moderate metabolic rates (3-Hz twitch contraction). These results suggest that specific interventions can improve specific indexes of function from established vasculopathy, but either this process was incomplete after 7-wk duration or measures of vascular structure are either resistant to reversal or require better-targeted interventions. NEW & NOTEWORTHY We used atorvastatin and/or chronic exercise to reverse established microvasculopathy in skeletal muscle of rats with metabolic syndrome. With established vasculopathy, atorvastatin and exercise had moderate abilities to reverse dysfunction, and the combined application of both was more effective at restoring function. However, increased vascular wall stiffness and reduced microvessel density were more resistant to reversal. Listen to this article’s corresponding podcast at https://ajpheart.podbean.com/e/reversal-of-microvascular-dysfunction/ .

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Interrater Reliability of Muscle Ultrasonography Image Acquisition by Physical Therapists in Patients Who Have or Who Survived Critical Illness

Physical Therapy ◽

10.1093/ptj/pzaa068 ◽

2020 ◽

Vol 100 (9) ◽

pp. 1701-1711 ◽

Cited By ~ 1

Author(s):

Kirby P Mayer ◽

Sanjay Dhar ◽

Evan Cassity ◽

Aaron Denham ◽

Johnny England ◽

...

Keyword(s):

Skeletal Muscle ◽

Intensive Care Unit ◽

Intensive Care ◽

Correlation Coefficient ◽

Intraclass Correlation Coefficient ◽

Interrater Reliability ◽

Physical Therapists ◽

Physical Therapist ◽

Image Acquisition ◽

Intraclass Correlation

Abstract Objective Previous studies have demonstrated that muscle ultrasound (US) can be reliably performed at the patient bedside by novice assessors with minimal training. The primary objective of this study was to determine the interrater reliability of muscle US image acquisition by physical therapists and physical therapist students. Secondarily, this study was designed to elucidate the process for training physical therapists to perform peripheral skeletal muscle US. Methods This was a cross-sectional observational study. Four novices and 1 expert participated in the study. Novice sonographers engaged in a structured training program prior to implementation. US images were obtained on the biceps brachii, quadriceps femoris, and tibialis anterior muscles in 3 groups: patients in the intensive care unit, patients on the hospital ward, and participants in the outpatient gym who were healthy. Reliability of image acquisition was analyzed compared with the expert sonographer. Results Intraclass correlation coefficient values ranged from 0.76 to 0.97 with an average for all raters and all muscles of 0.903, indicating excellent reliability of image acquisition. In general, the experienced physical therapist had higher or similar intraclass correlation coefficient values compared with the physical therapist students in relation to the expert sonographer. Conclusions Excellent interrater reliability for US was observed regardless of the level of experience, severity of patient illness, or patient setting. These findings indicate that the use of muscle US by physical therapists can accurately capture reliable images in patients with a range of illness severity and different clinical practice settings across the continuum of care. Impact Physical therapists can utilize US to obtain images to assess muscle morphology. Lay Summary Physical therapists can use noninvasive US as an imaging tool to assess the size and quality of peripheral skeletal muscle. This study demonstrates that physical therapists can receive training to reliably obtain muscle images in patients admitted to the intensive care unit who may be at risk for muscle wasting and may benefit from early rehabilitation.

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