A movimentação escapular é de grande importância para o funcionamento adequado do ombro. Indivíduos com disfunção no ombro apresentam uma diminuição da rotação superior e da inclinação posterior e um aumento da rotação interna da escápula durante a elevação do braço. Vários fatores estão envolvidos na alteração da cinemática escapular. Um deles é o encurtamento do músculo peitoral menor, sendo que indivíduos com comprimento de repouso reduzido desse músculo apresentaram diminuição da inclinação posterior e aumento da rotação interna da escápula durante o movimento do braço. Tal alteração cinemática é similar à apresentada por sujeitos com disfunção do ombro e pode ser um fator de risco para o desenvolvimento de sintomas. Portanto, o objetivo desse estudo foi avaliar a influência de um programa de alongamento da musculatura do aspecto anterior do ombro na cinemática escapular. O sistema eletromagnético de aquisição de dados foi utilizado para avaliar a cinemática escapular pré e pós um programa de alongamento da musculatura do aspecto anterior do ombro. Esse programa foi composto por três repetições de três exercícios de 30 segundos e teve duração de quatro semanas. O modelo linear de efeitos mistos foi utilizado para análise estatística das comparações entre as avaliações pré e pós-programa de alongamento. Não houve diferença estatisticamente significativa entre as avaliações antes e após a intervenção do estudo. Tal resultado sugere que o alongamento sozinho não é capaz de alterar a movimentação escapular, mas pode ser que contribua para o aumento da inclinação posterior se associado com outras intervenções. / The adequate scapular motion is very important to the shoulders function. Subjects with shoulder dysfunction present decreased scapular upward rotation and posterior tilt and increased scapular internal rotation during arm elevation. Many mechanisms are involved in scapular kinematics alteration. One of them is the pectoralis minor muscle shortening. Healthy subjects with relative short pectoralis minor resting length presented decreased upward rotation and increased internal rotation when compared with individuals with relative long resting length of this muscle. Hence, the purpose of this study was to evaluate the influence of the anterior shoulder aspect musculature stretching on scapular kinematics. The electromagnetic tracking device was utilized for kinematics analysis before and after a stretching program of the anterior shoulder aspect musculature. This program was composed by three repetition of three 30 seconds exercises and lasted for four weeks. The linear mixed effects model was used for statistical analysis of the comparison between pre and post stretching program evaluations. There was not a statistically significant difference between the pre and post intervention evaluations, Such outcome suggest that stretching alone cannot alter the scapular motion, but may contribute to the increase in posterior tilt if associates with others interventions.

Though the literature contains many computational models studying RSA, very few utilize finite element analysis to study stresses in the implant and the surrounding bone. The introductions section shows that many parameters (center of rotation lateralization, center of rotation superior or inferior position, tilt of the cut glenoid surface, glenosphere shape design, glenosphere size, humeral design, notch severity, etc.) have been studied independently utilizing many different methods (finite element modeling and non-FE computational modeling). However, the introduction section also detailed the current limitations in modern modeling as well as many examples of the heights to which finite element modeling can be taken to study RSA. Using these limitations as guidelines, the goal of this project is to create a robust FE model of RSA to study the effect of lateralization on scapular notching and shoulder function. In the following chapters, the development of the model is detailed. In addition, results produced by the incrementally advanced models are shown. In Chapter 2, the initial finite element model encompassing scapular and RSA hardware geometry is described. Chapter 3 contains description of incremental changes to the model including humeral geometry and muscle element incorporation. An anatomically realistic configuration of the finite element model with increased functionality is detailed in Chapter 4. Finally, Chapter 5 discusses the assets and limitations of the current model as a platform for future research. In addition, a proposed validation protocol is presented.

Despite a paucity of experimental evidence, clinical opinion remains that though LTrPs allow pain-free movement, they are primarily associated with deleterious motor effects and occur commonly in 'healthy' muscles. The primary aim of this study was to investigate the effects of LTrPs on the muscle activation patterns (MAPs) of key shoulder girdle muscles during scapular plane elevation of the arm in the unloaded, loaded and fatigued states. In connection with the main aim, a preliminary study was carried out to examine the frequency with which LTrPs occur in the scapular positioning muscles in a group of normal subjects. After establishing intra-examiner reliability for the clinical examination process, 154 healthy subjects volunteered to be screened for normal shoulder girdle function, then undergo a physical examination for LTrPs in the trapezius, rhomboids, levator scapulae, serratus anterior and the pectoralis minor muscles bilaterally. Of these 'healthy' subjects, 89.8% had at least one LTrP in the scapular positioning muscles (mean=10.65 ± 6.8, range=1-27), with serratus anterior and upper trapezius harbouring the most LTrPs on average (2.46 ± 1.8 and 2.36 ± 1.3 respectively). Consistent with clinical opinion, this study found that LTrPs occur commonly in the scapular positioning muscles. To investigate the motor effects of LTrPs, surface electromyography (sEMG) was used to measure the timing of muscle activation of the upper and lower trapezius and serratus anterior (upward scapular rotators), the infraspinatus (rotator cuff) and middle deltoid (arm abductor). These studies found that LTrPs housed in the scapular upward rotator muscles affected the timing of activation and increased the variability of the activation times of this muscle group and were also associated with altered timing of activation in the functionally related but LTrP-free infraspinatus and middle deltoid. Compared with the control group (all muscles LTrP-free), the MAPs of the LTrP group appeared to be sub-optimal, particularly in relation to preserving the subacromial space and the loading of the rotator cuff muscles. After the initial sEMG evaluations, the LTrP subjects were randomly assigned to one of two interventions: superficial dry needling (SDN) followed by post-isometric relaxation (PIR) stretching to remove LTrP s or sham ultrasound, to act as a placebo treatment where LTrPs remained. Where LTrPs were removed, a subsequent sEMG evaluation found MAPs to be similar to the control group in most of the experimental conditions investigated. Of particular note, when LTrPs had been treated and the subjects repeated the fatiguing protocol, the resultant MAP showed no significant difference with that of the control group in the rested state, suggesting treating LTrPs was associated with an improved response to fatigue induced by repetitive overhead movements. In conclusion, the findings indicate that LTrPs commonly occur in scapular positioning muscles and have deleterious effects on MAPs employed to perform scapular plane elevation and thus affect motor control mechanisms. Treating LTrPs with SDN and PIR stretching increases pressure-pain thresholds, removes associated taut bands and at least transiently optimises the MAP during scapular plane elevation. Discussion includes possible neuromuscular pathophysiology that might explain these results.

El propósito de nuestro estudio es optimizar la artrografía de hombro por vía anterior.78 pacientes fueron divididos de forma aleatorizada en grupos de 26 dependiendo del punto de inyección. Se registró el tiempo de radiólogo, la exposición a la radiación y la intensidad de dolor mediante la escala visual analógica (VAS) entre otras variables. Los grupos se compararon usando el análisis de varianza y el método de la mínima diferencia significativa.La exposición a la radiación, el tiempo de radiólogo y el dolor registrado en la escala VAS fue inferior cuando la inyección se realizó en el tercio superomedial, con diferencias estadísticamente significativas entre este punto y los otros dos (p<0,005).El punto óptimo para la inyección en la artrografía de hombro por vía anterior es el tercio superomedial, siendo un procedimiento sencillo, rápido y bien tolerado por los pacientes, así como con menor dosis de radiación. / The purpose of our study was to optimize anterior MR shoulder arthrography by comparing three injection sites.Seventy-eight patients were divided into three groups of 26 each, according to the injection site selected. Radiologist time and exposure time were recorded, and the intensity of the patient's pain was measured using a Visual Analogue Scale (VAS). Groups were compared using variance analysis and the least significant difference method.Shoulder arthrography was considered satisfactory for all three injection sites. Exposure and radiologist times and mean pain intensity registered by the VAS were lower when the injection was in the upper third; differences between the upper third and the other two areas were statistically significant (p < 0.005).The optimal injection site for anterior MR arthrography of the shoulder is the upper third of the humeral head, a simple, rapid procedure that is well tolerated by patients and reduces the radiation dose administered.

Despite a large prevalence of rotator cuff impingements or tears in the elderly population, little research has focused on understanding how this population adapts to perform tasks of daily living. Past research has focused on the analysis of upper limb kinematics of young healthy individuals while performing these essential tasks (Magermans, 2004, Murray and Johnson., 2004). The purpose of this thesis was to identify kinematic and shoulder loading differences between elderly mobile individuals and elderly individuals with rotator cuff impingements during specific activities of daily living. Motion capture techniques were used in combination with the Shoulder Loading Analysis Modules (Dickerson, 2005, Dickerson et al., 2007) to estimate thoracohumeral kinematics and calculate external joint moments. Two-tailed t-tests with injury status as the factor determined that differences in active range of motion in flexion/extension and humeral rotations existed between the two populations. Results of the ADL analysis showed that the impinged population tended to have decreased plane of elevation and humeral rotations during ADLs. Task was also a main factor for most variables examined. Perineal care, hair-combing and reaching tasks were the most demanding in terms of range of motion necessary to complete the task. The reaching tasks resulted in the highest shoulder moment. K-means clustering techniques proved to be unsuccessful in identifying different motion strategies between the two study groups. This investigation showed that developing adaptations for perineal care, hair-combing and reaching tasks should be considered a priority when working with patients with rotator cuff impingements, as these tasks demanded the largest ranges of motion as well as high shoulder moments.

Despite a large prevalence of rotator cuff impingements or tears in the elderly population, little research has focused on understanding how this population adapts to perform tasks of daily living. Past research has focused on the analysis of upper limb kinematics of young healthy individuals while performing these essential tasks (Magermans, 2004, Murray and Johnson., 2004). The purpose of this thesis was to identify kinematic and shoulder loading differences between elderly mobile individuals and elderly individuals with rotator cuff impingements during specific activities of daily living. Motion capture techniques were used in combination with the Shoulder Loading Analysis Modules (Dickerson, 2005, Dickerson et al., 2007) to estimate thoracohumeral kinematics and calculate external joint moments. Two-tailed t-tests with injury status as the factor determined that differences in active range of motion in flexion/extension and humeral rotations existed between the two populations. Results of the ADL analysis showed that the impinged population tended to have decreased plane of elevation and humeral rotations during ADLs. Task was also a main factor for most variables examined. Perineal care, hair-combing and reaching tasks were the most demanding in terms of range of motion necessary to complete the task. The reaching tasks resulted in the highest shoulder moment. K-means clustering techniques proved to be unsuccessful in identifying different motion strategies between the two study groups. This investigation showed that developing adaptations for perineal care, hair-combing and reaching tasks should be considered a priority when working with patients with rotator cuff impingements, as these tasks demanded the largest ranges of motion as well as high shoulder moments.

When designing work tasks, one goal should be to enable postures that maximize the force capabilities of the workers while minimizing the overall muscular demands; however, little is known regarding specific shoulder tissue loads during pushing and pulling. This study quantitatively evaluated the effects of direction (anterior-posterior pushing and pulling), handle height (100 cm and 150 cm), handle orientation (vertical and horizontal), included elbow angle (extended and flexed) as well as personal factors (gender, mass and stature) on hand force magnitudes, shoulder and L5/S1 joint moments, normalized mean muscle activation and electromyography (EMG)/force ratios during two-handed maximal push and pull exertions. Twelve female and twelve male volunteers performed maximal voluntary isometric contractions under 10 push and pull experimental conditions that emulated industrial tasks. Hand force magnitudes, kinematic data and bilateral EMG of seven superficial shoulder and trunk muscles were collected. Results showed that direction had the greatest influence on dependent measures. Push exertions produced the greatest forces while also reducing L5/S1 extensor moments, shoulder moments with the 150 cm height and overall muscular demands (p < 0.0001). The 100 cm handle height generated the greatest forces (p < 0.0001) and reduced muscular demands (p < 0.05), but were associated with greater sagittal plane moments (p < 0.05). Females generated, on average, 67% of male forces in addition to incurring greater muscular demands (p < 0.05). The flexed elbows condition in conjunction with pushing produced greater forces with reduced overall muscular demands (p < 0.0001). Furthermore, horizontal handle orientation caused greater resultant moments at all joints (p <. 0.05) The results have important ergonomics implications for evaluating, designing or modifying workstations, tasks or equipment towards improved task performance and the prevention of musculoskeletal injuries and associated health care costs.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 65-68).

Reverse shoulder arthroplasty (RSA) is a joint replacement procedure used mainly to treat patients with severe shoulder osteoarthritis combined with massive rotator cuff tears. It involves reversing the `ball and socket' orientation of the glenohumeral joint in the shoulder. While RSA has been largely successful in treating pain and improving function in these patients, complication rates remain high. Many of these complications, including joint instability and scapular notching (excessive bone wear), are caused or exacerbated by impingement of the humerus or the humeral component against the scapula. Adduction deficit refers to a patient's inability to fully adduct the arm due to impingement. Minimizing adduction deficit may improve RSA patients' functional outcomes. An existing mechanical shoulder simulator was further developed to model glenohumeral range of motion in RSA. The three heads of the deltoid were modelled using polyethylene cable and electric linear actuators with inline load cells. RSA components were implanted in Sawbones scapula and humerus bone models. The scapula was fixed in the frame of the simulator. Triads of optical tracking markers were attached to the humerus and simulator frame and used to track segment motion. A data analysis technique was developed to determine when joint impingement occurred. The convex and concave surfaces of the glenoid and humeral components were digitized, and a least-squares sphere fit was used to find their centres. The distance between these centres was then calculated during passive abduction and adduction of the humerus, and labeled d_GH. Impingement onset was defined as the point where d_GH was five standard deviations above its baseline value, indicating that the components were no longer concentric. This technique was used to determine the effects of humeral neck-shaft angle, socket depth, glenosphere diameter and eccentricity on range of motion and adduction deficit. A retentive humeral cup depth increased adduction deficit by 14 degrees and reduced range of motion by 26 degrees. A decreased neck-shaft angle reduced adduction deficit by 10 degrees but had little effect on overall range of motion. Diameter and eccentricity had no effect on either measure. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2014-04-03 13:34:07.404

In this work we defined the implications of the handgrip strength and the alternation of the shoulder joint during the 30-day period of rehabilitation. Thus, with the help of the regression method, as well as the modified exponential function, we aimed to create alternation models during the application period of kynezitherapy implements. This work concentrates on the alternation of the injured hand muscles’ strength and the mobility of the shoulder joint measurements, as well as the models of these measurements during the rehabilitation period. Our aims were: 1) to evaluate the probability of applying the modified exponential function, devising the models of alternation, concerning impetus to different age and sex groups, during the period of physiotherapy rehabilitation; 2) to identify the probability of applying the modified exponential function, devising the models of alternation, concerning joint mobility to different age groups, during the period of physiotherapy rehabilitation. 29 patients, divided into three age groups (21-35, 36-55, 56-70 year-olds), participated in a survey of hand tightening. These patients were also subdivided into groups, according to their sex. In the survey of the shoulder joint mobility, there were 18 participants, divided into the same age groups. According to the results of the survey, we came upon these conclusions: 1. Modified exponential function can be applied modeling the results of alternation, concerning the handgrip strength... [to full text]