Generating accurate simulations of the forces in the Glenohumeral joint is essential for investigation of normal and pathologic Shoulder function. It forms the basis for evaluating fracture treatment, joint replacement design and fixation. However, due to its complex anatomy and large range-of-motion, measuring the dynamic in-vivo forces and kinematics of the Glenohumeral joint remains a challenging problem in the field of biomechanics. This study shows the development and validation of a new testing medium for the Glenohumeral joint. The study uses a combined approach of in-vitro and in-silico testing and validates against previous data. This is achieved using a mechanical testing rig and finite element model which both closely represent the in-vivo Glenohumeral physiological characteristic including; geometry, muscular loading patterns, joint range-of-motion and external loadings. The mechanical model uses two instrumented implants based on current gold standard in-vivo testing. The two head types used are a Stem implant and a resurfacing head type implant. Comparison is made between the two head types as testing mediums for in-vitro testing. It is shown the resurfacing head more closely maintains the natural properties of the bone. Testing displays the significant advantages of in-vitro and in-silico testing over in-vivo testing. Validation is achieved by comparing simulated functional movements and activities of daily living to previous published data. When compared with previous data, recorded results from the mechanical testing rig shows high conformity. Comparison shows -3.95% and 4.14% error during 45° abduction with the resurfacing and stem implants respectively. Activities of daily living display similar loading patterns but lower maximum recorded force agreement. This has highlighted problems with unpredictable and complex muscular combinations when assessing complex movements. FE results show similar loading patterns and stress areas to previous data but record lower maximum forces than previous in-vivo data. Force and stress results from the FE model highlight the significant force increase external loads apply to the joint complex. Cross-validation between the mechanical testing rig and FE model shows high conformity and similar loading patterns. The developed medium is shown to be successfully validated against “gold standard” in-vivo data and other previous studies. Research experiments are used to illustrate the variety of testing possible with the developed medium and to further develop and validate the design. Research into trauma, injury and fixation is discussed and joint forces measured. This data lays a foundation for future testing using the developed test medium. The testing medium provides repeatable and reproducible results for forces within the Glenohumeral joint. This can now be used to further understand joint kinematics, injuries, fracture prorogation and fixation. It will also provide a valuable training aid for a complex joint. Better understanding, testing and training of new techniques, tools and traumas is now possible. This will aid in reducing injury prevalence, severity, healing time and ultimately improving patient quality of life.

Title: Effect of rehabilitation intervention on soft tissue of shoulder joint in handball players Objectives: The aim of the thesis is to explore the benefits of 10-session conservative therapy in handball players diagnosed with throwing shoulder. The chosen therapy should eliminate the players' difficulties as much as possible and allow them to once again fully engage in the activity. Methods: Experiment-based qualitative research with randomized control study was conducted. The objective was to assess the findings of four probands - players of a major-league team - diagnosed with shoulder joint soft tissue injury caused by playing handball. Two women and two men between the ages of 19 and 30 took part in the research. The subjects were divided into two groups. The first group, a man and a woman, took part in 10 therapeutic sessions, whereas the other did not receive any kind of treatment and served as a reference group. Both initial and final kinesiologic examinations were carried out at the beginning and the end of the therapy, consisting of anamnesis, physical inspection, palpation, anthropometric and goniometric measuring, examination of muscle, muscle shortening, joint movement and movement stereotype. Measured data was analysed and evaluated. Results: After ten successive therapeutic...

A high degree of variability is commonly encountered in biomechanical investigations of the shoulder. Researchers have hypothesized that the variation between individuals explains why only certain workers are injured when performing the same tasks as other individuals. One source for the variability is inter-individual differences in shoulder musculoskeletal geometry. The purpose of this thesis was to use computational modeling to assess the functional roles of the scapulohumeral muscles, compare model-predicted data to the reviewed literature, and quantify the sensitivity of these functional roles to changes in muscle geometry. Muscle moment arms, lines of action, stability ratios, and forces were quantified throughout arm elevation in the scapular plane using a widely investigated upper extremity model. Monte Carlo simulations were performed to iteratively adjust muscle attachment locations in order to reflect potential inter-individual differences in muscle geometry. Model-predicted muscle moment arms agreed well qualitatively with the reviewed literature; however, several muscle lines of action were inconsistent between the model and previous data collected in cadavers available in the literature. Sensitivity of muscle functional roles to attachment changes was muscle-specific, and depended upon the elevation angle as well as outcome measure. Regressions were developed to identify which attachment locations at the clavicle, scapula, and humerus caused the greatest change in muscle functional roles. In general, muscle moment arms were most sensitive to changes of the muscle attachment closest to the joint centre (humeral attachment for rotator cuff muscles; scapular attachment for deltoids). Lines of action were most affected by perturbations in scapular attachment location. Overall, these findings indicate that inter-individual musculoskeletal geometry differences can substantially alter muscle functional roles, which are expected to require altered muscle activity and kinematic coordination patterns between people. These variations in musculoskeletal geometry may differentially affect risk of work-related shoulder musculoskeletal disorders among individuals. / Thesis / Master of Science (MSc)

Reverse shoulder arthroplasty (RSA) is performed to decrease pain and improve function and range of motion (ROM) primarily for patients with rotator cuff arthropathy, an arthritis of the shoulder secondary to rotator cuff insufficiency. However, RSA has suffered from high early to mid-term rates of complication, with instability being one of the most common. The shoulder biomechanics post-RSA depend on multiple factors such as implant geometry, positioning, and cuff integrity. This study built upon prior finite element (FE) analysis of RSA to investigate the effects of glenoid lateralization and retentive liner design on shoulder stability. A previously validated FE model was extended to model shoulder external rotation (ER) after implantation of the Zimmer Trabecular Metal RSA system. The FE model included the scapula bone with an implanted glenosphere implant, the humerus bone with implanted humeral sections of the RSA implant, and muscle tendons representing the subscapularis, infraspinatus, and deltoid. Six different models matched glenospheres in three cases of lateralization (2mm, 4mm, and 10mm) with two humeral poly liner designs (normal: 150° neck shaft angle or retentive: 155° neck shaft angle). Using Abaqus/Explicit FE software, the proximal ends of the soft tissues were pulled to their anatomical positions, and then fixed in space while the humerus was externally rotated 80° about the humeral long axis from a neutral position with the shoulder abducted 25°. The displacements, deltoid and subscapularis forces, impingement-free ROMs, and subluxation gap distances were recorded. Although greater glenosphere lateralization was associated with higher impingement-free ROM, larger deltoid and subscapularis forces developed. Deltoid tension contributes to shoulder stability and control, but elevated amounts of deltoid tension may contribute to scapular fractures and greater stress at impingement sites post-RSA. Further analysis such as inclusion of more anatomical features and additional motions may offer greater insight to orthopedic surgeons when planning for RSA insertion.

Introduction The length of a muscle has been described as one of the factors contributing to the ideal movement at a joint. A decrease in the length of a muscle results in a decrease in the range of motion at the joint in direct relation to the function of that specific muscle. M Latissimus Dorsi is a muscle which undergoes length changes (loss of extensibility) and this muscle has a functional role in many aspects of sport and rehabilitation. The loss of extensibility may result in a decreased range of motion at the glenohumeral joint leading to dysfunction. Evidence-based practise requires the use of objective, valid and reliable tests for measuring the length of a muscle. No scientific evidence of reliability for any documented technique testing the length of m Latissimus Dorsi (LD) was found. Aim The aim of this study was to assess the inter-rater and intra-rater reliability of a technique adapted by Commerford and Mottram (2012) for assessing the length of LD. Study design The design of the study is a within-participant test-retest non-experimental quantitative study for reliability purposes Method Fifty-six volunteering students recruited from the Physiotherapy Department of the University of Pretoria were the participants in this study. Four qualified physiotherapists with varying numbers of years of clinical experience independently performed the test for assessing the length of LD. The test was performed twice by each physiotherapist on every participant and two measurement sessions were done. A pilot study was also done. Data Analysis and conclusion A sample of 56 participants provided an intraclass correlation coefficient (ICC) of less than 0.9 and this is regarded as poor reliability. The agreement between each rater and the differences in the two levels of experience of raters were also assessed. The ICC was used to determine the inter-rater and intra-rater reliability of the LD length test. A 0.05 level of significance was employed. The ICC between the experienced raters was found to be 0.48 with a novice rater ICC of 0.48 as well. The ICC between all the raters was 0.33. This constitutes poor reliability. The poor reliability of the technique testing the length of LD was identified and addressed in order for adequate usage thereof, in research and in practice. Recommendations of a new technique to test the length of LD was provided by the researcher. A suggestion was made regarding a manner of testing its reliability. / Dissertation (MPhysT)--University of Pretoria, 2014. / Physiotherapy / MPhysT / Unrestricted

No description available.

The glenohumeral joint is the most dislocated joint in the body due to the lack of bony constraints and dependence on soft tissue, primarily muscles and ligaments, to stabilize the joint. The goal of this study was to develop a computational model of the glenohumeral joint whereby joint behavior was dictated by articular contact, ligamentous constraints, muscle loading, and external perturbations. Validation of this computational model was achieved by comparing predicted results from the model to the results of a cadaveric experiment in which the relative contribution of muscles and ligaments to anterior joint stability was examined. The results showed the subscapularis to be critical to stabilization in both neutral and external rotations, the biceps stabilized the joint in neutral but not external rotation, and the inferior glenohumeral ligament resisted anterior displacement only in external rotation. Knowledge gained from this model could assist in pre-operative planning or the design of orthopedic implants. Use of this model as a companion to cadaveric testing could save valuable time and resources.

Title: Evaluation of the physiotherapy effectiveness in women handball players with an anterior instability of the glenohumeral joint. Objectives: The aim of this diploma thesis is to summarize the anterior instability of the glenohumeral joint knowledge in women handball players. Subsequently to perform and evaluate the effect of the three months long physiotherapy intervention based on proprioceptive neuromuscular facilitation by which we wanted to eliminite the anterior instability of the glenohumeral joint. In the last part of the research are compared the results which were reached by the group which did the three months intervention program and the control group without any physiotherapeutical intervention. Methods: The experiment was performed in handball team HC Slavia Praha by women players range in age from 15 -19 years. It was carried out using 3 tests evaluating the instability of the anterior glenohumeral joint, which were evaluated by 2 different physiotherapists and 3 motor tests evaluating the explosive force of the upper limb. Testing was performed twice, before and after the three months long physiotherapeutical intervention. Results: After the three months intervention, there was a significant improvement of the results in the group which underwent the physiotherapy intervention....

Introdução: O déficit de rotação interna glenoumeral, freqüentemente observado em praticantes de esportes que envolvem movimentos repetidos do membro superior sobre a cabeça, tem sido associado ao surgimento de lesões secundárias no ombro. Objetivos: Medir e comparar a amplitude de rotação interna glenoumeral em praticantes assintomáticos de tênis e natação, esportes com características diferentes, mas que envolvem esse tipo de movimento. Métodos: 54 voluntários assintomáticos do sexo masculino (108 ombros) divididos em 3 grupos (tenistas, nadadores, grupo-controle) foram submetidos à medida da amplitude de rotação interna glenoumeral através do método de exame clínico com estabilização da escápula (delineamento de pesquisa: estudo transversal). Foram comparadas as medidas dos ombros dominante e não dominante dentro de cada grupo e entre os grupos. Resultados: Em todos os grupos, o ombro dominante apresentou déficit de rotação interna se comparado com o não dominante. No grupo de tenistas o déficit médio foi de 23,9° ± 8,4° (P< 0,001), no de nadadores foi de 12° ± 6,8° (P< 0,001), e no grupocontrole de 4,9° ± 7,4° (P= 0,035). Comparados os membros dominantes entre os grupos, houve diferença entre todos, sendo o déficit apresentado pelos tenistas em relação ao grupo-controle (27,6°;P< 0,001) maior do que o dos nadadores (17,9°; P<0,001); entre tenistas e nadadores, foi de 9,7°;P=0,002). Conclusões: O membro dominante apresentou menor amplitude de rotação interna glenoumeral do que o não dominante em todos os grupos, sendo o déficit dos tenistas cerca de duas vezes maior do que o dos nadadores. A diferença média entre os membros no grupo controle foi menor do que 5°, o que está dentro do parâmetro de normalidade de acordo com a maioria dos estudos. Todos os grupos apresentaram diferenças se comparados os membros dominantes entre si. Os tenistas apresentaram a menor amplitude de rotação interna seguidos pelos nadadores. / Background: Glenohumeral internal rotation deficit, often diagnosed in players of overhead sports, has been associated with the development of secondary shoulder pathologies. Aim: To measure and compare the range of glenohumeral internal rotation motion in asymptomatic tennis players and in swimmers, different sports that share this overhead movements. Methods: Fifty-four asymptomatic male volunteers (108 shoulders) divided in 3 groups (tennis players, swimmers, control group) underwent measurements of glenohumeral internal rotation using clinical examination with scapular stabilization (study design: cross-sectional study). Measurements of dominant and nondominant shoulders were compared within and between groups. Results: In tennis players, mean déficit was 23.9° ± 8.4° (P< 0.001); in swimmers, 12° ± 6.8° (P< 0.001); and in the control group, 4.9° ± 7.4° (P= 0.035). Dominant shoulders showed significant difference between all groups, and the déficit of the group of tennis players in comparison with the control group (27.6°;P< 0.001) was greater than the deficit found in the group of swimmers (17.9°; P<0.001); between tennis players and swimmers, the deficit was 9.7°;P=0.002). Conclusions: Dominant limbs showed less glenohumeral internal rotation than the nondominant limbs in all groups, being the deficit in the group of tennis players about twice the deficit found for swimmers. Mean difference between limbs in the control group was less than 5°, which is within normal parameters according to most studies. There were statistically significant differences between all groups when dominant shoulders were compared to each other. Tennis players had the least range of motion, followed by swimmers.

Introdução: O déficit de rotação interna glenoumeral, freqüentemente observado em praticantes de esportes que envolvem movimentos repetidos do membro superior sobre a cabeça, tem sido associado ao surgimento de lesões secundárias no ombro. Objetivos: Medir e comparar a amplitude de rotação interna glenoumeral em praticantes assintomáticos de tênis e natação, esportes com características diferentes, mas que envolvem esse tipo de movimento. Métodos: 54 voluntários assintomáticos do sexo masculino (108 ombros) divididos em 3 grupos (tenistas, nadadores, grupo-controle) foram submetidos à medida da amplitude de rotação interna glenoumeral através do método de exame clínico com estabilização da escápula (delineamento de pesquisa: estudo transversal). Foram comparadas as medidas dos ombros dominante e não dominante dentro de cada grupo e entre os grupos. Resultados: Em todos os grupos, o ombro dominante apresentou déficit de rotação interna se comparado com o não dominante. No grupo de tenistas o déficit médio foi de 23,9° ± 8,4° (P< 0,001), no de nadadores foi de 12° ± 6,8° (P< 0,001), e no grupocontrole de 4,9° ± 7,4° (P= 0,035). Comparados os membros dominantes entre os grupos, houve diferença entre todos, sendo o déficit apresentado pelos tenistas em relação ao grupo-controle (27,6°;P< 0,001) maior do que o dos nadadores (17,9°; P<0,001); entre tenistas e nadadores, foi de 9,7°;P=0,002). Conclusões: O membro dominante apresentou menor amplitude de rotação interna glenoumeral do que o não dominante em todos os grupos, sendo o déficit dos tenistas cerca de duas vezes maior do que o dos nadadores. A diferença média entre os membros no grupo controle foi menor do que 5°, o que está dentro do parâmetro de normalidade de acordo com a maioria dos estudos. Todos os grupos apresentaram diferenças se comparados os membros dominantes entre si. Os tenistas apresentaram a menor amplitude de rotação interna seguidos pelos nadadores. / Background: Glenohumeral internal rotation deficit, often diagnosed in players of overhead sports, has been associated with the development of secondary shoulder pathologies. Aim: To measure and compare the range of glenohumeral internal rotation motion in asymptomatic tennis players and in swimmers, different sports that share this overhead movements. Methods: Fifty-four asymptomatic male volunteers (108 shoulders) divided in 3 groups (tennis players, swimmers, control group) underwent measurements of glenohumeral internal rotation using clinical examination with scapular stabilization (study design: cross-sectional study). Measurements of dominant and nondominant shoulders were compared within and between groups. Results: In tennis players, mean déficit was 23.9° ± 8.4° (P< 0.001); in swimmers, 12° ± 6.8° (P< 0.001); and in the control group, 4.9° ± 7.4° (P= 0.035). Dominant shoulders showed significant difference between all groups, and the déficit of the group of tennis players in comparison with the control group (27.6°;P< 0.001) was greater than the deficit found in the group of swimmers (17.9°; P<0.001); between tennis players and swimmers, the deficit was 9.7°;P=0.002). Conclusions: Dominant limbs showed less glenohumeral internal rotation than the nondominant limbs in all groups, being the deficit in the group of tennis players about twice the deficit found for swimmers. Mean difference between limbs in the control group was less than 5°, which is within normal parameters according to most studies. There were statistically significant differences between all groups when dominant shoulders were compared to each other. Tennis players had the least range of motion, followed by swimmers.