Musculoskeletal Alterations Research Articles

Association between thoracic musculoskeletal abnormalities and lung function in preterm infants.

In view of the difficulties and risks of performing lung function tests in infants and the hypothesis that children with abnormal pulmonary test may exhibit thoracic musculoskeletal alterations. This study aimed to determine the frequency of abnormal lung function and their relationship. This was a cross-sectional study with children from 6 to 12months of corrected age, born at a gestational age of <37weeks and with a birthweight ≤1500g, who were subjected to a lung function test and photogrammetry--an objective and non-invasive procedure. To verify the association between the thoracic musculoskeletal abnormalities and measure changes in lung function, univariate linear regression was used. The level of statistical significance was setted at P<0.05. Of the 38 infants, 12 (31.6%) exhibited abnormal lung function, including 9 (23.7%) with obstructive function and 3 (7.9%) with restrictive function. A significant association was noted between forced expiratory volume at 0.5second <-2 z score and the acromion/xiphoid process/acromion angle (β=4.935); forced vital capacity <-2 z score and the angle of the manubrium/left acromion/trapezium (β=0.033) and forced expiratory volume at 0.5second and forced vital capacity ratio <-2 z score and the inframammillary point/xiphoid process/inframammillary point angle (β=0.043). Preterm infants with very low birthweight presented a high frequency of abnormal lung function, particularly obstructive type and thoracic musculoskeletal abnormalities were associated with changes in lung function.

Anomalía de Poland, a propósito de dos casos

Introducción: el síndrome de Poland, conocido también como secuencia de Poland o anomalía de Poland, fue descrito por primera vez por Alfred Poland en 1841. Corresponde a una alteración musculoesquelética congénita, caracterizada por la ausencia total o parcial del músculo pectoral mayor, asociada a anormalidades de la extremidad superior ipsilateral.&#x0D; Objetivo: se presentan dos casos de niñas que consultaron por asimetría mamaria, en el primer caso una niña de 12 años con ausencia del pectoral mayor y antecedente de postquirúrgicos sindactilia de mano derecha ipsilateral. El segundo caso, una niña de 9 años con asimetría mamaria sin alteración en la extremidad.&#x0D; Conclusión: la anomalía de Poland o secuencia de Poland es una alteración musculoesquelética de presentación infrecuente, de aparición esporádica, de mayor prevalencia en masculinos, afecta generalmente el lado derecho del cuerpo, muy pocas veces amerita tratamiento quirúrgico.

Genetic and clinical characterization of 73 Pigmentary Mosaicism patients: revealing the genetic basis of clinical manifestations

BackgroundPigmentary mosaicism constitutes a heterogeneous group of skin pigmentation alterations associated with multisystem involvement. The aim of this study was to establish a complete cytogenetic and molecular characterization of PM patients, emphasizing on searching for possible low chromosomal mosaicism and on establishing an accurate genotype-phenotype correlation.ResultsA total of 73 patients were included (3 months to 18 years of age), 52% male and 48% female. Observed in 69 (95%) patients, the most frequent pattern of pigmentation was fine and whorled BL, which was associated with disseminated skin extent in 41 (59%) patients. Central nervous system (84%) alterations were the most frequent observed in the group of patients, followed by the musculoskeletal (53%) and ophthalmologic (27%) alterations. Considering the pattern of pigmentation, no significant differences in association with skin extent or extracutaneous manifestations were detected. Following a strict cytogenetic analysis strategy, screening metaphases from three different tissues (peripheral blood, hyperpigmented and hypopigmented skin) we found that 23/73 patients had chromosomal abnormalities classified as follows: 1) Mosaic with 2 or more different cell lines with structural alterations n = 19; 2) Polyploidy (mosaic) n = 1 and 3) Alterations in all cells in three different tissues n = 3. SNP array, array CGH and FISH were useful for the complete characterization of the chromosomal aberrations, for the detection of microdeletions in patients with normal karyotype but with strong clinical suspicious of chromosomal alteration, and for a better establishment of genotype-phenotype correlation. In 2 patients we found genes associated with some of the extracutaneous manifestations (SHH, MNX1, PPP2R2C).ConclusionsThis group of 73 patients finely described is the largest series of patients with pigmentary mosaicism reported worldwide. As we showed in this study, the followed analysis strategy allowed the detection of cytogenetic and molecular abnormalities, and made possible the establishment of genotype-phenotype associations in some patients. An important limitation of our study was the analysis of fibroblasts cultures instead of melanocytes and keratinocytes. In some cases the direct molecular DNA analysis of skin biopsy could be another choice.

Índice de pie plano y zonas de mayor prevalencia de alteraciones músculo-esqueléticas en jóvenes deportistas

Introduction and objectivesFlatfoot and pescavus can affect the physical performance of athletes and increase the onset of musculoskeletal disorders. The objective of this paper was to determine the degree of flatfoot, pescavus and musculoskeletal disorders suffered in relation to age, gender and sport practiced, in young athletes between 9 and 20 years of age. MethodologyOne hundred and ninety-one young athletes participated in the study (58.6% women and 41.4% men), average mass of 57.99±12.86kg and average height of 1.61±0.11m. The sports considered were: basketball, baseball, soccer, weightlifting, handball, karate, swimming, rowing and volleyball. The soles of the feet were digitized with a PodoScan and the Chippaux-Smirak index was obtained. Next, each participant was asked a series of questions to analyse the musculoskeletal alterations suffered during the practice of sports and the areas or regions of the body with the highest prevalence were recorded. ResultsA high percentage of pes cavus was found in young athletes, mainly women. Women presented 30.2% of normal pes cavus in the right foot while men presented 19.2%. The knee was the part of the body most affected with a 31.4% prevalence followed by the ankle at 17.8%. ConclusionThis paper found that women have the highest percentage of prevalence of injuries and there are parts of the body predisposed to suffer a musculoskeletal disorder in relation to the sport practiced.

Novel imaging approaches to the quantification of musculoskeletal alterations in X-linked hypophosphatemic rickets (XLH)

Searchable abstracts of presentations at key conferences on calcified tissues ISSN 2052-1219 (online)

DIAGNOSTIC AND THERAPEUTIC CHARACTERISTICS IN THE APPROACH OF DIABETIC FOOT IN THE ELDERLY.

This article systematically evaluates the most used diagnostic measures for the management of diabetic foot in the elderly, the decision making in the surgical approach, the tertiary prevention of the disease and the microbiological behavior. The initial diagnostic study for musculoskeletal infections and alterations is conventional radiography (sensitivity 40-75%, specificity 60-90%), computed tomography is more useful in the approach to chronic infection, assessing bone abductions and deformities. Magnetic resonance (sensitivity 100%, specificity 40%) is useful to assess the formation of abscesses and bone compromises.Decision-making in the surgical approach is due to sensory, motor or mixed neuropathy; which predispose to ulcers, fractures, deformities and fissures of the skin; lesions that are overinfected and must be operated on. Infections in elderly people with diabetic foot show that Staphylococcus Aureus is the main pathogen causing osteomyelitis. Beta-hemolytic Streptococci / S. Aureus, in patients with cellulitis, without open cutaneous wound, except in repeated mono microbial cultures, immunosuppressed patients or ulcers that do not respond to treatments. The diagnosis and treatment of diabetic foot continues to be a challenge for the health system; it is important that health institutions form interdisciplinary groups aimed at improving patient conditions, who must perform timely, adequate treatment, with routine monitoring and follow-up; using diagnostic methods throughout the course of the disease in order to reduce the need for amputations of the extremities.Keywords: Therapeutic approach, Diabetic Foot, osteomyelitis.

Musculoskeletal Alterations of Hindlimb During Simulated Microgravity and Reloading in Rats: Compared by Gender

Although several researches have reported potential gender differences in adaptations during microgravity, the musculoskeletal alterations of different genders are still under debate. Besides, there were few researches which involved recovery phase after reloading. In the present study, we investigated the musculoskeletal alterations of rats hindlimb via tail-suspension in both genders, and analyzed the serum sex hormone at the same time. Thirty-two Sprague Dawley rats were equally divided by gender into four groups randomly: control of male (CONM), tail-suspension of male (TSM), control of female (CONF) and tail-suspension of female (TSF). The experiment consisted two phases, which were 21 days of tail suspension phase and 21 days’ reloading phase, and parameters of bone, muscle and serum were tested at the end point of each phase. The results indicated that during tail suspension phase, male rats showed a greater and earlier bone loss and microstructure deterioration compared with females, but they could maintain muscle strength much better. In addition, during reloading phase, male rats showed a slower bone recovery and some parameters could not recover until the end, while loss in muscle mass and strength in both genders could recover to control level.

Pelvic floor muscle training for prevention and treatment of urinary incontinence during pregnancy and after childbirth and its effect on urinary system and supportive structures assessed by objective measurement techniques.

During the second and the third trimesters of pregnancy and in the first 3months following childbirth, about one-third of women experience urinary incontinence (UI). During pregnancy and after delivery, the strength of the pelvic floor muscles may decrease following hormonal and anatomical changes, facilitating musculoskeletal alterations that could lead to UI. Pelvic floor muscle training (PFMT) consists in the repetition of one or more sets of voluntary contractions of the pelvic muscles. By building muscles volume, PFMT elevates the pelvic floor and the pelvic organs, closes the levator hiatus, reduces pubovisceral length and elevates the resting position of the bladder. Objective of this review is to evaluate the efficacy of PFMT for prevention and treatment of UI during pregnancy and after childbirth and its effect on urinary system and supportive structures assessed by objective measurement techniques. The largest medical information databases (Medline-Pubmed, EMBASE, Lilacs, Cochrane Library and Physiotherapy Evidence Database) were searched using the medical subject heading terms "pelvic floor muscle training", "prevention", "urinary incontinence", "urinary stress incontinence", "objective measurement techniques", "pregnancy, "exercise", "postpartum" and "childbirth" in different combinations. Overall, the quality of the studies was low. At the present time, there is insufficient evidence to state that PFMT is effective in preventing and treating UI during pregnancy and in the postpartum. However, based on the evidence provided by studies with large sample size, well-defined training protocols, high adherence rates and close follow-up, a PFMT program following general strength-training principles can be recommended both during pregnancy and in the postnatal period.

PROPOSAL FOR INTERVENTION THROUGH REBA FOR THE PREVENTION OF WORK-RELATED OSTEOMUSCULAR DISORDERS (WRMS)

This study presents a bibliographical review about the evaluation of the main complaints of the attendants of a real estate company located in the city of Iranduba/AM. to designate the set of injured musculoskeletal alterations, affected by the workers. To evaluate the main indicative complaints of WMSD. The research was conducted in the internal facilities of the company object of this study. Where a questionnaire was applied with the aid of the REBA tool. The sample of this research was composed by 6 collaborators who work in the company attendance in the morning and afternoon shifts. Data collection took place in June 2019. The data collected through this study indicated important indications of the body regions most susceptible to musculoskeletal disorders related to the profession of attendant.

Prediction of height and body mass index based on body segments: Use of Gauld's equations in an Argentine sample.

When height cannot be measured or does not account for actual bone growth in children, due to their condition, it may be estimated using equations based on body segments. 1. To compare observed height (OH) and predicted height (PH) based on body segments using the equations of Gauld et al. 2. To analyze its applicability in the estimation and interpretation of body mass index (BMI). A sample of children and adolescents without musculoskeletal alterations. Height, arm span, length of the ulna, the forearm, the tibia and the leg, weight, and pubertal development were registered. BMI was estimated. Differences and agreements between OH and PH were analyzed using the Bland-Altman method and an intraclass correlation coefficient. For BMI, the absolute prediction error and agreement were estimated using a Kappa coefficient. Two hundred and twenty children and adolescents aged 6.04-19.1 years were included. The intraclass correlation coefficient between PH and OH was > 0.9 in all equations. In average, PH overestimated OH by less than 2.0 cm, except when using the ulna length (2.6 cm among girls and 3.4 m among boys). The average absolute prediction error for BMI was < 5 %, except for the ulna length, and the Kappa coefficient was > 0.7. In our sample, the equations of Gauld et al. were adequate to predict height and estimate BMI. The greatest difference between observed height and predicted height was observed when using the ulna length.

Prevalência de distúrbios osteomusculares e a alteração da postura em profissionais de berçário

OBJETIVO: verificar a prevalência de distúrbios osteomusculares e alterações posturais nas profissionais de Berçários do município de Jaraguá do Sul/SC. MÉTODOS: Foi realizado um estudo transversal, participaram 92 mulheres, utilizou-se um questionário socioeconômico, seguido da aplicação do questionário Nórdico, para verificar os sintomas musculoesqueléticos. A análise postural foi realizada pelo software SAPO. RESULTADOS: constatou-se que 56,52% apresentaram dor, sendo o agachar o movimento mais citado, e a coluna lombar como a região mais afetada. Quanto ao questionário Nórdico, a coluna lombar teve a maior queixa, tanto nos últimos doze meses com uma média de 29,34%, e nos últimos sete dias, 46,73%. Todas as informações foram ao encontro com os resultados do software SAPO, que identificou uma elevada alteração postural na coluna lombar. CONCLUSÃO: A alta prevalência de distúrbios osteomusculares e alterações posturais nas profissionais de Berçários, chama a atenção principalmente em relação a sintomatologia. São necessários mais estudos deste tema, com o objetivo primordial de promoção e prevenção à saúde destas profissionais.

Arthritis in type 2 diabetes mellitus

Objectives The objective of this study was to estimate the correlation between diabetes mellitus (DM) and arthritis through some laboratory changes in patients with type 2 DM complaining of arthropathy. Patients were recruited from outpatient clinics of Internal Medicine Department at Menoufia University Hospital. Background DM has become one of the main threats to human health in recent decades. Uncontrolled diabetes is strongly correlated to causing long-term microvascular and macrovascular complications. Rheumatological diseases are now common, which have an increased prevalence in the diabetic population. Patients and methods The study included 90 patients. Patients were divided into three groups: group 1 comprised 30 patients with type 2 DM without arthropathy, group 2 comprised 30 patients with type 2 DM with arthropathy, and group 3 comprised 30 nondiabetic patients with arthropathy. Results BMI was significantly higher among patients with arthropathy (33.64 ± 2.26), random blood sugar was significantly higher among patients with arthropathy (288.10 ± 83.64), Alc was significantly higher among patients with arthropathy (8.72 ± 1.09), erythrocyte sedimentation rate was significantly higher among nondiabetic patients (58.60 ± 27.29), serum uric acid was significantly higher among nondiabetic patients (5.11 ± 1.18), C-reactive protein was higher among diabetic patients with arthropathy (60%), rheumatoid factor was significantly higher among patients with arthropathy (75.0%), and antinuclear antibody was significantly higher among patients with arthropathy (98.0%). Conclusion Musculoskeletal complications were most commonly seen in patients with a long-standing history of type 2 DM. The incidence of DM and the life expectancy of the diabetic patient have both increased, resulting in increased prevalence and clinical importance of musculoskeletal alterations in diabetic patients. The development of musculoskeletal disorders is dependent on age and the duration of DM.

Phacomatosis Pigmentovascularis

AbstractThe coexistence of a widespread vascular nevus and an extensive pigmentary nevus is defined as “phacomatosis pigmentovascularis” (PPV). More than 250 (sporadic) cases of PPV have been so far reported, mainly in Asian or Asian-related populations: mutations in genes related to angiogenic pathways (RAS, MAPK, mTOR, PI3K/AKT, and GNAQ) have been recently identified as the causes of this complex phenotype. In many cases, mutations in two different genes may coexist, representing the classical example of “twin spotting” phenomenon. PPV is usually associated with several extracutaneous anomalies including ocular manifestations (melanosis bulbi, glaucoma, iris mammillations, megalocornea, buphthalmos, strabismus, and hyperpigmentation of the conjunctiva, sclera, episclera, iris, trabecular meshwork, and choroid) and musculoskeletal alterations (limb hypertrophy, Klippel–Trenaunay type abnormalities, hemifacial hypertrophy, hemicorporal hypertrophy, macrocephaly, microcephaly, and scoliosis). Central nervous system anomalies have been reported in most of the patients and include seizure, cognitive delay, cerebral atrophy, hydrocephalus, sensorineural deafness, and intracranial hypertension, as well as migraine, pseudotumor cerebri, and intracerebral vascular malformations. More rarely, PPV has been associated with structural and/or vascular renal anomalies, hepatosplenomegaly, pyogenic granuloma, cavernous hemangioma, portal hypertension, umbilical hernia, hypoplasia of leg veins, and hypo- or hyperactivity of the immune system.

Tongue reduction in Beckwith–Wiedemann syndrome: outcome and treatment algorithm

Beckwith–Wiedemann syndrome is a rare congenital overgrowth disorder with macroglossia being one of the cardinal symptoms. In pronounced cases, macroglossia can lead to airway obstruction, musculoskeletal alterations and functional deficits. Surgical tongue reduction is performed at varying ages and with different techniques. This study evaluated perioperative complications, as well as long-term aesthetic and functional outcomes, in a large cohort. A total of 68 patients, treated either surgically or conservatively, were included. Depending on the severity of macroglossia, patients were divided into three groups to determine the treatment algorithm. Complications after surgical tongue reduction were prolonged intubation and revision due to dehiscence or haematoma. In the long term, no patient suffered from impaired sense of taste or paresthesia, although the shape of the tongue was disproportional in 85%. With the present treatment algorithm, operative tongue reduction exerts a positive influence on skeletal, dentoalveolar and functional development with sufficient long-term outcome and high grade of satisfaction of the patients. Supportive therapy in an interdisciplinary centre is of fundamental importance for both surgical and conservative treatment.

P.223 - Postural and gait patterns assessed by 3D movement analysis in a late onset Pompe disease sibship

Late onset Pompe disease (LOPD) is characterized by significant motor disabilities, which affect in particular ambulation. Only one study reports on spatial-temporal parameters of gait assessed in a clinical heterogeneous group of unrelated patients. In this study spatiotemporal and kinematic gait patterns are described in a genetically homogenous group of LOPD patients using 3d movement analysis. 7 LOPD siblings, harbouring the same GAA mutations compound, were assessed with clinical scales and with 3d movement analysis to measure spatial-temporal and kinematic parameters during gait cycle and “sit to stand test”. Relevant abnormalities were observed either in spatial-temporal and kinematic parameters. The former consisted in a trend towards a decreased velocity and cadence, a prolonged time in double limb support, shorter step and stride length, and a widening of base of support; the latter in an increased anterior pelvic-tilt and posterior trunk-tilt during the whole gait cycle, a decreased pelvic obliquity, active hip extension and ankle dorsiflexion. This study shows, in homogenous group of LOPD patients, either spatial-temporal and kinematic deviations that may improve understanding of the musculoskeletal alterations, the evolution of disease and the answer to the enzyme replacement therapy.

Predictive simulation of diabetic gait: Individual contribution of ankle stiffness and muscle weakening

Diabetic neuropathic individuals present massive muscle strength reduction at the ankle plantar- and dorsiflexors and increased joint stiffness. Our aim is to investigate the adaptation strategies to these musculoskeletal alterations during walking by means of predictive simulations. We used a seven segment planar musculoskeletal model actuated by eight Hill-type muscles in each leg. The effect of all passive tissue in muscles and other joint structures was modeled by net passive joint moment curves. The predictive simulations were generated by solving an optimal control problem that minimized a cost function, including effort and tracking terms, using direct collocation and a commercial optimal control package. We simulate four conditions to represent the weakening of the distal muscles triceps sural (TS) and tibialis anterior (TA), and five conditions to represent the effect of increasing nonlinear ankle stiffness in flexion. The weakening of the distal muscles leads to a delayed action of the TS and a progressive decrease of the gastrocnemius peak force in the push-off phase. This distal deficit is compensated by a larger hip flexion moment resulting from an increase in the iliopsoas muscle force in this phase, known as the hip strategy. The adaptation mechanisms observed in response to an increase in ankle stiffness include the hip strategy and the exploitation of the passive joint structures as springs, which store energy during midstance and release it during push-off, reducing TS force and power in this phase and leading to a consistent decrease in the overall muscle force levels.

Pengaruh Latihan Gerak Aktif Kaki dengan Teknik Open Kinetic Chain Exercise terhadap Penurunan Intensitas Nyeri pada Lansia dengan Nyeri Sendi Osteoartritis dan Rheumatoid

Tidak ada latihan khusus untuk orang tua dengan rasa sakit yang disebabkan oleh Osteoarthritis dan rheumatoid di lembaga sosial Minaula Lansia di Kendari. Penelitian ini bertujuan untuk memeriksa efek dari latihan kaki dengan metode rantai kinetik terbuka pada penurunan rasa sakit pada orang tua dengan rasa sakit yang disebabkan oleh Osteoarthritis dan rheumatoid. Metode yang digunakan dalam penelitian ini adalah quasi eksperimental menggunakan Pretest dan posttest dengan desain kelompok kontrol. Pengumpulan data dilakukan dengan pengambilan sampel acak sederhana untuk mencapai 60 peserta 930 dalam kelompok intervensi dan 30 dalam kelompok kontrol). Hasilnya menunjukkan bahwa berarti tingkat nyeri kelompok intervensi menurun sebagai 4, 83 setelah latihan kaki dengan metode rantai kinetik terbuka (berarti sebelum 5, 80, berarti setelah 0, 97). Kesimpulan dari penelitian ini ada efektivitas latihan kaki dengan metode rantai kinetik terbuka untuk menurunkan tingkat rasa sakit pada orang tua dengan rasa sakit yang disebabkan oleh Osteoarthritis dan rheumatoid di Minaula lembaga sosial Lansia di Kendari 2016 (nilai p = 0000). Penelitian ini menyiratkan bahwa latihan kaki dengan metode rantai kinetik terbuka dapat dipertimbangkan sebagai salah satu kompetensi Keperawatan dan diterapkan sebagai intervensi keperawatan untuk penurunan tingkat nyeri yang disebabkan oleh Osteoarthritis dan rheumatoid.

Resistance Training as a Tool for Preventing and Treating Musculoskeletal Disorders.

The aging process is characterized by several physiological, morphological, and psychological alterations that result in a decreased functional and health status throughout the life span. Among these alterations, the loss of muscle mass and strength (sarcopenia) is receiving increased attention because of its association with innumerous age-related disorders, including (but not limited to) osteoporosis, osteoarthritis, low back pain, risk of fall, and disability. Regular participation in resistance training programs can minimize the musculoskeletal alterations that occur during aging, and may contribute to the health and well-being of the older population. Compelling evidence suggest that regular practice of resistance exercise may prevent and control the development of several musculoskeletal chronic diseases. Moreover, resistance training may also improve physical fitness, function, and independence in older people with musculoskeletal disorders, which may result in improved quality of the years lived. In summary, regular participation in resistance training programs plays an important role in aging and may be a preventive and therapeutic tool for several musculoskeletal disorders.

Orthopaedic Aspects of Marfan Syndrome: The Experience of a Referral Center for Diagnosis of Rare Diseases

Marfan syndrome is caused by mutations in the fibrillin-1 gene (FBN1). The most important features affect the cardiovascular system, eyes, and skeleton. The aim of this study was to report the most frequent musculoskeletal alterations observed in 146 patients affected by Marfan syndrome. Fifty-four patients (37%) underwent cardiac surgery and 11 of them received emergent surgery for acute aortic dissection. Ectopia lentis was found in 68 patients (47%) whereas myopia above 3D occurred in 46 patients (32%). Musculoskeletal anomalies were observed in all patients with Marfan syndrome. In 88 patients (60.2%), the associated “wrist and thumb sign” was present; in 58 patients (39.7%), pectus carinatum deformity; in 44 patients (30.1%), pectus excavatum; in 49 patients (33.5%), severe flatfoot; in 31 patients (21.2%), hindfoot deformity; in 54 patients (36.9%), reduced US/LS ratio or increased arm span-height ratio; in 37 patients (25.3%), scoliosis or thoracolumbar kyphosis; in 22 patients (15%), reduced elbow extension (170° or less). Acetabular protrusion was ascertained on radiographs in 27 patients (18.4%). Orthopaedic aspects of the disease are very important for an early diagnosis; however, we have not observed definite correlations between the extent of orthopaedic involvement and aortic complications.

Musculoskeletal Atrophy in an Experimental Model of Knee Osteoarthritis: The Effects of Exercise Training and Low-Level Laser Therapy.

The aim of this study was to evaluate the effects of an exercise training protocol and low-level laser therapy (and the association of both treatments) on musculoskeletal atrophy using an experimental model of knee osteoarthritis (OA). Fifty male Wistar rats were randomly divided into five groups: control group, knee OA control group, OA plus exercise training group, OA plus low-level laser therapy group, and OA plus exercise training associated with low-level laser therapy group. The exercise training and the laser irradiation started 4 wks after the surgery, 3 days per week for 8 wks. The exercise was performed at a speed of 16 m/min, 3 days per week, 50 mins per day, for 8 wks. Laser irradiation was applied at two points of the left knee joint (medial and lateral), for 24 sessions. The results showed that both trained groups (irradiated or not) presented a significant increase in the muscle cross-sectional area and a decrease in muscle fiber density compared with the knee OA control group. Moreover, both trained and laser-irradiated groups demonstrated decreased muscle-specific ring-finger protein 1 and atrogin-1 immunoexpression. These results suggest that exercise training and low-level laser therapy were effective in preventing musculoskeletal alterations related to atrophy caused by the degenerative process induced by knee OA.