M.Tech. (Chiropractic) / Aim: The aim of this study was to determine the effects of chiropractic adjustment therapy (CAT) to the cervical spine on the reflex motorneuron excitability of C5 and C6 nerves on the biceps brachii muscle bilaterally. This study was also aimed at measuring the subsequent increase in strength of the biceps brachii muscle. Method: A selection of 30 participants, male or female and between the ages of 18 and 40 were recruited. Participants had to meet all the inclusion criteria and present with no contra-indications. Only one group was used as each participant served as their own control. Participants were seen seven times over a period of three weeks. The measurements were taken during the 1st, 4th and 7th consultations. On the 2nd, 3rd, 5th and 6th consultations only treatment was applied. On the 7th consultation only data was collected and no treatment was done. Results: Statistically significant improvement of dynamometry and electromyographic measurements were noted over the consultation periods on both sides. No conclusion could be made regarding the comparison of dynamometer and sEMG measurements of the biceps brachii between each consultation and between each side (left and right) over the study period. Conclusion: Based on the results obtained in this research it may be deduced that CAT may have an effect on the neurological system and further more an effect by increasing motorneuron excitability at sites distant to the spine itself. These results are important to the Chiropractic profession as it shows that CAT does not only produce a segmental response, but that there are wide spread effects on structures distant to the spinal column. The extent of the effects CAT can elicit on the nervous system requires further investigation.

<p> The force-velocity and force-length relationships of skeletal muscle have been thoroughly investigated in the literature. Unfortunately many of the relationships that have been applied to models of the human anatomy have been based upon investigations that have been performed under in-vitro conditions. It was the intention of this study to investigate whether the relationships determined by in-vitro investigation and assumed to be correct could accurately and properly be applied to actual human examples. Previous investigation by Leedham and Dowling (1991) displayed that when investigating human elbow flexors and in particular the biceps brachii that the force-length relationship did not concur with in-vitro results. The purpose of this study was to investigate the relationships between length, velocity, EMG and force of the biceps muscle. </p> <p> Eight young adult males (22-26) were fastened into an isoveloci ty device ( CYBEX) which allowed only flexion and extension of the right elbow. The forearm was then rotated eccentrically or concentrically through a range of motion from 50 to 170 degrees of extension (or vice-versa). The biceps muscle was either maximally contracted voluntarily or was excited using electrical stimulation at 40 Hz. Using the constant angle torque (CAT) method and three dimensional surfaces the force-velocity, force-length and EMG-velocity relationships were investigated. <p> <p> The main conclusions of the study were that the neural drive provided by electrical stimulation over the motor point provided CMAPS of consistent amplitude regardless of the joint angle or angular velocity. The concentric force-velocity relationship of the biceps was in agreement with most accounts in the literature however the eccentric contraction condition displayed a peak force production at 30° Is then showed a slight decline to plateau across faster eccentric velocities. Increased eccentric force production was thought to be more mechanical than neurological in nature. </p> / Thesis / Master of Science (MSc)

Although rare, distal biceps tears are common in middle-aged men in their 4th and 5th decades of life. The evidence surrounding prognosis, complications and rehabilitation interventions for distal biceps ruptures are of poor quality and therefore, many questions remain to be answered. This thesis includes four manuscripts describing studies that aim to improve our understanding of the rehabilitation of surgical and non-surgical management of distal biceps tendon rupture, prognostic factors associated with surgical repair and the outcomes for non-surgical management. The first manuscript is a scoping review of rehabilitation procedures described in the literature for the management of distal biceps ruptures. Overall, rehabilitation descriptions for distal biceps ruptures are poor for both post-surgical and non-surgical management. The findings suggest heterogeneity, both on the reporting and the content of rehabilitation delivered as a stand-alone intervention or post-operatively. The second manuscript is a cross-sectional study evaluating potential factors associated with reduced function post double incision surgical repair. The findings suggest that having a smoking history and weaker biceps flexion strength are associated with a poor prognosis and accounted for 50.4% of the variability in functional scores. These findings support existing studies that indicate a smoking history is associated with less favourable pain, function and disability outcomes follow distal biceps repair. The third manuscript is a prospective study evaluating prognostic factors associated with reduced function for those undergoing double incision surgical repair. These findings suggest that the majority of persons undergoing a distal biceps repair using a two-incision approach have minimal complications and good functional outcomes. In addition, having surgery on the non-dominant hand and having a weaker grip strength at baseline accounted for 43.4% of the variability of functional scores. The fourth manuscript describes two cases of non-surgical management of a complete distal biceps rupture. Despite the common belief that surgical repair for biceps rupture results in superior elbow flexion and supination strength, these cases demonstrated that full recover of strength and function is possible through rehabilitation alone. This study contributes to the evidence-base by questioning the need for surgical repair for all cases of distal biceps ruptures. / Dissertation / Doctor of Philosophy (PhD) / The biceps tendon is prone to rupture where it inserts into the elbow. While not a common injury, it does occur more often in middle aged men following a forceful movement. Most of the research regarding the prognosis and management of distal biceps ruptures is of poor quality and imprecise due to small sample sizes. This thesis examined management in a set of studies. A scoping review indicated that rehabilitation descriptions for distal bicep ruptures were of very poor quality for both surgical and non-surgical management for this condition. A cross-sectional analysis of 60 patients revealed that having a smoking history and weaker flexion strength was associated with poor outcomes after distal biceps repairs. A prospective cohort study of 34 patients found that having surgery on the non-dominant arm and weaker grip strength was associated with poor outcomes 6-12 months after surgical repair. Given the excellent outcomes after surgery and presumption of the need for surgery as standard practice, there has been little attention to the role of conservative management. We evaluated two cases where patients refused surgery and were able to recover full strength and functional abilities using a comprehensive rehabilitation program. This thesis confirms that excellent outcomes occur after this injury and raises the need for future trials comparing surgery and rehabilitation as treatment options. The fact that this injury often occurs in healthy men may partially explain the excellent outcomes with surgery or rehabilitation.

Schultererkrankungen nehmen in sozioökonomischer Hinsicht einen Spitzenplatz unter den Erkrankungen des Bewegungsapparates ein.58 Die häufigen „klassischen Schultererkrankungen“ wie Schulterinstabilitäten, Rotatorenmanschettenrupturen und Omarthrosen sind schon sehr lange bekannt und durch viele Studien gut untersucht. Demgegenüber stellen Läsionen des Aufhängeapparates der langen Bizepssehne (LBS) eine sehr junge Schulterpathologie dar, über die es noch wenige Daten gibt. Im Jahre 1994 formten Walch et al.62 für diese komplexe intraartikuläre Halteschlinge der LBS den Begriff des „stabilizing pulley“, oder Bizepspulley. Im Folgenden sollen Anatomie, Funktion und Pathologie des Bizepspulleys mit allen wichtigen anatomischen Strukturen kurz erläutert werden. / This study retrospectively analyzed 1007 diagnostic shoulder arthroscopies. The study included 72 patients with an arthroscopically verified pulley lesion as the main pathologic finding. Epidemiologic data and arthroscopic findings were evaluated in all patients, and 53 were clinically examined with the Constant score after a minimum follow-up of 2 years. We observed an incidence of 7.1% for pulley lesions. An isolated rupture of the superior glenohumeral ligament (SGHL) was seen in 53 patients (73.6%) and a combined partial articular-side tear of the rotator cuff adjacent to rotator interval in 19 (26.4%). Thirty-one patients (43%) had a history of trauma, whereas 41 (57%) had none. Overall, the mean postoperative Constant score adjusted for age and gender was 80.1% (range, 47%-135%). Patients with a SGHL lesion only (85.7%) exhibited a significant (P = .047) higher age- and gender-adjusted Constant score compared with patients with a combined partial surface tendon tear (73.1%). Our epidemiologic data accentuate the need for careful evaluation of the superolateral aspect of rotator interval to avoid underdiagnosis of pulley lesions at shoulder arthroscopy. Our findings provide evidence that the clinical outcome of isolated SGHL lesions is better compared with combined partial articular-side rotator cuff tear. With respect to the progressive pathologic process of pulley lesions, we recommend an early surgical treatment.

Early strength increase with training is normally attributed to neural adaptations but recent evidence suggests that muscle hypertrophy occurs earlier than previously thought. The purpose of this study was to examine the time course of adaptation through 20 days of training and 5 days of detraining. Twenty-two untrained subjects trained one arm every 2nd day for 20 days. Subjects performed isokinetic eccentric biceps training at 90°/s (6 sets of 8 reps). Muscle thickness (reported in cm) via ultrasound, strength (reported in Nm) and muscle activation (electromyography) were measured before, during and after training (9 time points). Muscle thickness increased after 8 days of training (3.66±0.11 to 3.90±0.12; p<0.05) and remained above baseline until the end of training (3.97±0.12). After 5 days of detraining muscle thickness decreased (3.97±0.12 vs. 3.85±0.11; p<0.05), but remained higher than baseline (p<0.05). Muscle thickness did not change significantly in the untrained arm at any time point. Strength in the trained arm decreased after 8 days of training (65.6±4.1 to 57.5±3.5; p<0.05) and remained suppressed throughout the study. Muscle activation amplitude increased after 14 days of training (p<0.05) and remained elevated throughout the study. In conclusion, biceps muscle thickness increases very rapidly with frequent intense eccentric training although this type of training appears to impair strength. These findings provide additional evidence that muscle hypertrophy may occur much faster than has been generally accepted.

Early strength increase with training is normally attributed to neural adaptations but recent evidence suggests that muscle hypertrophy occurs earlier than previously thought. The purpose of this study was to examine the time course of adaptation through 20 days of training and 5 days of detraining. Twenty-two untrained subjects trained one arm every 2nd day for 20 days. Subjects performed isokinetic eccentric biceps training at 90°/s (6 sets of 8 reps). Muscle thickness (reported in cm) via ultrasound, strength (reported in Nm) and muscle activation (electromyography) were measured before, during and after training (9 time points). Muscle thickness increased after 8 days of training (3.66±0.11 to 3.90±0.12; p<0.05) and remained above baseline until the end of training (3.97±0.12). After 5 days of detraining muscle thickness decreased (3.97±0.12 vs. 3.85±0.11; p<0.05), but remained higher than baseline (p<0.05). Muscle thickness did not change significantly in the untrained arm at any time point. Strength in the trained arm decreased after 8 days of training (65.6±4.1 to 57.5±3.5; p<0.05) and remained suppressed throughout the study. Muscle activation amplitude increased after 14 days of training (p<0.05) and remained elevated throughout the study. In conclusion, biceps muscle thickness increases very rapidly with frequent intense eccentric training although this type of training appears to impair strength. These findings provide additional evidence that muscle hypertrophy may occur much faster than has been generally accepted.

Noninvasive viscoelasticity imaging, or “dynamic elastography”, methods have recently been developed to objectively quantify the local viscoelastic properties of soft tissues by measuring the local propagation velocity of mechanical shear vibrations (e.g. faster velocity indicates stiffer material). But, the existing elastography technologies require a potentially uncomfortable external mechanical stimulation (e.g. vibrations probe) to induce muscle vibrations; and sophisticated and expensive imaging equipments (such as MRI and ultrafast ultrasound elastography), involving complex signal processing, to record and analyze these muscle vibrations. The work in this dissertation lays the foundation for the development of a low cost, passive, non-invasive elastography by analyzing and processing Surface Mechanomyograms (S-MMGs) measured with one dimensional accelerometers from the biceps brachii muscle. Aim 1 of this dissertation focused on the 3-dimensional aspect of vibrations measured by accelerometers on the skin surface above the biceps brachii. While Aim 2 focused on using one-dimensional accelerometers to determine the propagation direction of the propagating S-MMG waves. Using this newly developed knowledge on S-MMG Aim 3 was accomplished, a method to analyze the propagating wave and develop a metric that can track the changes in the muscle was developed, namely, the coherence length. The coherence length was found to significantly increase with increased contraction levels for all seven of the subjects. Overall the results of this study show that the propagation features of S-MMG vibrations reflect the architecture and contraction level of the biceps brachii muscle. Hence S-MMG could potentially be used for monitoring physiological changes of skeletal muscles.

Orientador: Mathias Vitti / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-27T15:26:22Z (GMT). No. of bitstreams: 1 Verri_EdsonDonizetti_M.pdf: 2091762 bytes, checksum: 8d7b8fd3fff4ba87b179b020ea70d390 (MD5) Previous issue date: 2001 / Resumo: O objetivo deste trabalho foi estudar a influência dos músculos bíceps do braço (cabeças curta e longa), braquiorradial e tríceps do braço (cabeças lateral, longa e medial), na atividade flexora do antebraço em diferentes posições articulares do ombro. Foram testadas contrações isométricas de flexão do antebraço semipronado a 90° com flexão de ombro a 90°, ombro neutro e ombro a 90° de abdução. Foram estudados dez voluntários jovens, do sexo feminino, com idades de 20 a 30 anos, e destros. Todos os voluntários eram não treinados e sem história de doença neuromuscular ou articular. Os registros foram obtidos, utilizando-se um eletromiógrafo computadorizado modelo MCS - V2 da LynxElectronicsLtda. Com módulo condicionador de sinais de 16 canais, e placa A/D modelo CAD 12/36 da Lynx Electronics Ltda. de 12 bites de resolução de faixa dinâmica, filtro do tipo Butterworth, de passa-baixa de 509 Hz, de passa-alta de 10,6 Hz, ganho 10 vezes e freqüências de amostragem de 1.000 Hz; software Aqdados versão 4,16 da Lynx Electronics Ltda. para apresentação dos sinais de diferentes canais simultaneamente e tratamento do sinal (valor de RMS, média, mínimo, máximo, e desvio padrão). Os sinais eletromiográficos foram captados por eletrodos de superflcie ativos diferenciais de superfície (Lynx Electronics Ltda). Os valores de RMS obtidos foram submetidos à análise estatística no programa GraphPad InStat, versão 3,01, Free Demo. Os dados foram testados quando a normalidade de distribuição pelo teste de Kolmogorov-Smirnov, e as comparações entre as médias de RMS foram feitas pelos testes ANOVA e Kruskal-Wallis. A correlação de Pearson foi usada para estabelecer uma relação entre a força de contração registrada e o sinal eletromiográfico de cada um dos músculos estudados. Através destes testes, os resultados mostraram que nos músculos estudados, não houve diferenças estatísticas para a atividade eletromiográfica e força de contração isométrica causada pela variação do posicionamento articular do ombro. Os valores de correlação de Pearson mostraram, para os flexores do antebraço, maior correlação no posicionamento neutro do ombro, enquanto o valor médio de RMS do músculo tríceps foi mais correlacionado com a força registrada com a articulação do ombro posicionada em 90° de abdução. O músculo tríceps do braço age em cocontração para proteger e estabilizar as articulações do cotovelo e do ombro durante os registros da contração isométrica de flexão do antebraço em esforço máximo. A variação dos comprimentos dos músculos biarticulares não foi suficiente para alterar os níveis de força e do sinal eletromiográfico, nas contrações isométricas de flexão do antebraço, combinadas com a semipronação e as variações dos posicionamentos articulares do ombro, sugerindo uma maior contribuição destinada à estabilização das articulações do cotovelo e do ombro / Abstract: The purpose of this study was to analyze the influence of biceps raquialis, braquiorradial, and triceps braquialis on the flexon activity at different positions of the shoulder joint. It was observed the isometric semipronate elbow flexion contractions with anatomical position of the shoulder, 90° shoulder flexion and 90s houder abduction. Ten healthy female young volunteers, right-handed and no-trained were evaluate. The registers of electromyographic and force output were acquired by a 12 bit A/D converter board with a sample frequency of 1000 Hz, Butterworth filter with low-pass of 509 Hz and high-pass of 10,6 HZ (model CAD 12/36 of Lynx Electronics Ltda.), and gain of 1000 times. The Aqdados software 4.16 version (Lynx Electronics Ltda) was used to present and analyze the different signals simultaneously (RMS, mean, standard deviation, maximum, minimum values). The electromyographic signals were detected with a differential bipolar surface electrode (Lynx Electronics Ltda.) over the musc1ebelly placed between a motor point and the tendon insertion. The force output was measured with a load cell.In all trials, the load celI was positioned with it alignrnent perpendicular to the limb. The RMS and force mean values were statisticalIy evaluated by the GraphPad InStar, 3,01 Free Demo version. The data were tested with Kolmogorov-Smimov normal distribution test, and the mean RMS and force comparison were performed by ANOVA and Kruskal-Wallis tests. The Pearson correlation was used to establish a relationship between RMS and force values for each of the studied musc1es. The results showed that no statistical differences were found to electromyographic activity and force output in the isometric elbow flexion contractions caused by the variation of the shoulder position. The Pearson correlation values showed that greater correlation for the flexor musc1esoccurred at 90° of the shoulder abduction, while the greater correlation for the triceps braquialis occurred at anatomical shoulder position. The triceps braquialis musc1e act in cocontraction to protect and stabilize the shoulder and elbow joints during the isometric elbow flexion contractions in maximum effort. The length variation of the biarticular musc1e by the shoulder variation in the isometric elbow flexion contractions combined with semipronation was not enough to alter the force levels of the force output and electromyographic signals. This suggest that the greater contribution of the contraction of the studied musc1eswas destined to stabilization of the shoulder and elbow joints / Mestrado / Mestre em Biologia e Patologia Buco-Dental

M. Tech. / OBJECTIVE: The aim of the study was to explore whether dry needle therapy delivered to latent myofascial trigger points of the biceps brachii muscle had an immediate effect on muscle activity and strength . DESIGN: One hundred participants with latent myofascial trigger points of the biceps brachii muscle and who were suitable for the study were drawn from the community. They were al located in to either a controlor treatment group so that each group contained fifty participants . The control and treatment group were divided in such a way to ensure that the two groups were comparable with one another un terms of age and gender. The International Physical Activity Questionnaire was completed by each participant to ensure that the two groups were also comparable with one another in terms of the total amount of physical activity performed per week. The results of this study were statistically analysed by STATKON at the University of Johannesburg.

The purpose of this study was to examine changes in muscle ultrastructure and strength performance following a single bout of elbow flexor resistance exercise. Eight untrained males performed 8 sets of 8 repetitions at 80% concentric 1 RM. One arm performed only the concentric (CON) phase of the movement while the other performed only the eccentric (ECC) phase. Maximum isometric (MVC), low (LV} and high velocity (HV} concentric peak torque, and evoked contractile property measurements of the elbow flexors were made before and after the bout, and at 24, 48, 72 and 96 h. Needle biopsies were obtained from the biceps brachii prior to the exercise, immediately post-exercise from each arm (POSTCON, POST-ECC}, and 48 h post-exercise from each arm (48H-CON, 48H-ECC). Electron microscopy was used to quantify the extent of fiber disruption in each sample. The severity of disruption was classified as focal (FOC}, moderate (MOD}, or extreme (EXT}. All strength measurements decreased (P s; o. 05} below pre-exercise values immediately post-ex in both arms, but dramatic differences were observed between arms during the subsequent recovery period. MVC, LV, HV and peak twitch torque (PTT) recovered to pre-ex values by 24 h in the CON arm. In the ECC arm, HV did not recover for at least 72 h, and MVC, LV and PTT remained depressed at 96 h. ANOVA revealed a greater (P s; 0.05) number fibers were disrupted in the POST-CON, POST-ECC, 48H-CON and 48H-ECC samples compared to BASE. Significantly more fibers appeared disrupted in the POST-ECC (82%) and 48H-ECC (80%) samples compared to the POSTCON (33%) and 48H-CON (37%) samples, respectively. In addition, the POST-ECC (41%) and 48H-ECC (50%) samples contained a greater number of fibers with EXT disruption compared to the POST-CON (13%) and 48H-CON (17%) samples. Decreases in MVC at 48 h correlated (P ~ 0.05) with the extent of EXT disruption in the 48H-CON and 48H-ECC samples. These data indicate that both the CON and ECC phase of weightlifting produce myofibrillar disruption, with the greatest disruption occurring during the ECC phase. This study was supported by the Natural Sciences and Engineering Research Council of Canada. / Thesis / Master of Science (MSc)