This thesis analyzes the nonextensive generalization of Boltzmann-Gibbs statistics and study its applications to some physical models such as isotropic rigid and non-rigid rotators. The thesis will also try to show what kind of internal energy constraint must be chosen for entropy optimization in a mathematically consistent manner.

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Submitted in partial compliance with the requirements for the Masters Degree in Technology: Chiropractic at the Durban University of Technology, 2009. / Aim: The aim of the study was to assess the effect of a single versus multiple cervical spine manipulations, over a two week period, on peak torque of the rotator cuff muscles utilizing the Cybex Orthotron II Isokinetic Rehabilitation System. This study was a pre and post experimental investigation. Method: Forty asymptomatic (in terms of neck and shoulder pain) male chiropractic students were stratified into two equal groups of twenty subjects to ensure that each group consisted of an equal number of subjects from each year of study. All subjects underwent a familiarisation session on the Cybex Orthotron II Isokinetic Rehabilitation System. Group One received a single manipulation. Rotator cuff peak torque was measured pre-manipulation, immediately post manipulation and at a two-week follow up. Group Two received four manipulations over a two week period. Rotator cuff peak torque was measured pre and immediately post the first manipulation. A third rotator cuff peak torque measurement was taken two weeks after the first manipulation. Results: There was no statistically significant effect of a single or multiple manipulations on rotator cuff peak torque (abduction, adduction, internal rotation and external rotation). Inter-group analysis revealed a trend of an effect for abduction as the single manipulation increased at the two-week follow up and the multiple manipulation group decreased; however, this was not statistically significant. Conclusion: No statistically significant results were found possibly due to small sample size and the fact that objective measurements were only taken at the beginning and the end of the research processes and not at regular intervals throughout the study.Further studies are needed to determine the effects of multiple manipulations on peripheral muscle activity, including the treatment of symptomatic patients with rotator cuff pathology. It is also recommended that EMG readings be done in conjunction with peak torque measures to determine muscle activity.

Rotator cuff tendinopathy accounts for the majority of cases of shoulder pain, however, the aetiology and pathophysiology of the condition is poorly understood and treatment interventions for the condition have been introduced on an empirical basis, guided only by unproven theories of biological and structural changes in and around the affected tissue. This thesis explores changes in the provision of surgical interventions for rotator cuff tendinopathy, showing a rapid, sustained increase over the last decade. Investigation into the use of ultrasound as a clinical and research tool led to the development of an independent learning method for surgeons using the modality for shoulder imaging and highlighted the technological limitations of contrast enhanced ultrasound in assessing the microvascularity of the supraspinatus tendon. Development of a novel biopsy method for sampling the supraspinatus tendon permitted collection of tissue samples from several cohorts of individuals with rotator cuff tendinopathy. These studies, for the first time, described tissue changes across the whole spectrum of pathology suggesting the possibility of an early inflammatory phase of the condition followed by tissue senescence and reduced viability as pathology progressed. Paired samples taken before and after treatment identified reduced tissue activity in response to glucocorticoid therapy and a potential healing response from the supraspinatus tendon following surgical repair. Significant deterioration in tissue activity and viability was shown as age increased in a large cohort of individuals, highlighting the major impact of ageing as a factor in the onset and progression of rotator cuff tendinopathy. The techniques introduced provide standardised, reproducible methods for further evaluation of rotator cuff tendinopathy and the development of novel therapeutic interventions.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Reverse total shoulder arthroplasty is used as the treatment for arthritic rotator cuff deficient shoulders. Some of the most common complications of a reverse shoulder arthroplasty are scapular notching, glenoid dissociations, glenohumeral dislocation, loosening or dissociation of the humeral component and nerve injury. Clinical outcomes are dependent on the preoperative diagnosis, the function of the deltoid and remaining rotator cuff muscles, biomechanical design of the prosthesis, and the orientation and placement of the reverse shoulder component. This study aims to optimize the patient-specific placement of a reverse shoulder component. A simulation software package was developed that can be used to determine the optimal placement of the reverse shoulder prosthesis for a specific patient. This is achieved by maximizing the humerothoracic range of motion and minimizing the adduction deficit. The motion of the simulation model is driven by shoulder complex motion equations adjusted for each patient. This data was obtained from literature with the motion of the arm fixed to the coronal, scapular and sagittal elevation planes. The influence of the various components of the Tornier Aequalis® - Reversed II system, together with changing the glenoid component inclination and humeral component retroversion, was investigated. This allowed the simulation software to be verified and validated, as well as applying the insight and knowledge gained to a case study. Further simulations evaluated a design change of the humeral component neck-shaft angle from the standard 155 ° to 145 ° or 165 °. The reverse shoulder simulation software provides accurate patient-specific Three Dimensional (3D) pre-operative planning and shoulder complex motion simulation. / AFRIKAANSE OPSOMMING: Omgekeerde volledige skouerartoplastie word as behandeling van ontsteking in gewrigsomhulsel-aangetaste skouers gebruik. Onder die algemeenste komplikasies van 'n omgekeerde skouergewrig-operasie is kepe in die skouerblad (skapulier), lostrekkings of onthegting van die gewrigskom (glenoïede), ontwrigting van die boarm/skouergewrig, die loskom of onthegting van die boarmbeen en beskadiging van senuwees. Mediese resultate is afhanklik van diagnose voor die operasie, die werking van die driehoekspier (deltoïede) en oorblywende draaispiere, die biomeganiese ontwerp van die prostese en die oriëntasie en plasing van die omgekeerde skouerkomponent. Hierdie studie is gemik op die beste pasiënt-spesifieke plasing van die omgekeerde skouerkomponent. Die simulasie-sagtewarepakket wat ontwikkel is, kan gebruik word om die optimale plasing van die omgekeerde skouerprostese in die geval van 'n spesifieke pasiënt te bepaal. Dit word gedoen deur die bewegingsvermoë van die bo-armbeen te maksimaliseer en die gebrekkige werking van die trekspiere te minimaliseer. Die werking van die simulasiemodel word gedryf deur die beweging van skouerkomponente te vergelyk, aangepas vir elke pasiënt. Hierdie data is verkry uit literatuur en die koppeling van die arm se beweging aan die belangrikste, skouerblad- en sagittale elevasievlakke. Die invloed van die onderskeie komponente van die Tornier Aequalis® - Reversed II-stelsel is saam met die verandering van die gewrigskom-komponent se helling en bo-armkomponent se terugstoting ondersoek. Sodoende kon die simulasie-sagteware nagegaan, bevestig en geldig verklaar word; en die insig en kennis wat verkry is op 'n gevallestudie toegepas word. Met verdere simulasies is 'n ontwerpwysiging ge- ëvalueer waar die skouerkomponent se beenpyphoek vanaf die standaard van 155° na 145° of 165° verander is. Die omgekeerde skouersimulasiesagteware maak akkurate pasiëntspesifieke driedimensionele (3D) beplanning voor 'n operasie en simulasie van die bewegings skouerdele moontlik.

A dissertation in partial compliance with the requirements for a Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2005. / Although studies of manipulation-induced peripheral changes in the muscles have been done, inconsistencies noted by the author’s call for further investigation into the reflex effects of manipulation. Additionally, according to the literature, no effective treatment protocol for the painful shoulder has been found. Therefore this research aimed at addressing these discrepancies by quantifying the immediate effect of cervical spine manipulation in terms of peak torque on rotator cuff musculature in asymptomatic patients with both a cervical spine dysfunction and without. And thus by investigating cervical manipulation to the C4-C7 spinal segment, as a possible added intervention for improving rotator cuff muscle peak torque, a more efficient and effective management protocol for the painful shoulder could be attained. Thus the aims for this study included: 1) To evaluate whether manipulation has an effect on rotator cuff peak torque or not, utilizing the Cybex Orthotron II Isokinetic Rehabilitation System; 2) To ascertain whether manipulation of the specific levels has an effect on the rotator cuff peak torque or not and 3) To ascertain whether the presence or absence / M

Rotator cuff injury is a debilitating condition and when injury cannot be managed through non-operative procedures, surgery is required. To determine explanations for the failure of surgery to restore joint function, human muscle biopsies of supraspinatus were studied compared to deltoid. Histology showed atrophy and a tendency toward fibrosis/fatty infiltration in injured supraspinatus. Findings from AChR-subunit western blot and Sema3A localization around satellite cells suggest supraspinatus denervation. Nucleotide incorporation to quantify satellite cell activation in culture showed a significant increase in BrdU+(active) satellite cells in supraspinatus treated with a nitric oxide-donor drug, but not deltoid muscle. The application of principal component analysis to these data extracted components that suggest variables assaying muscle atrophy, satellite cell activity, and fibrosis contribute strongly to the observed variability. The results suggest supraspinatus muscle of the injured rotator cuff is atrophic, denervated, possibly subject to fibro-fatty infiltration, and support the idea that treatment could promote growth in atrophic supraspinatus to improve functional outcomes. / October 2015

Undesirable work factors, such as awkward upper body postures and repetitive arm motion, in the workplace can lead to upper extremity pain. Research suggests that these work-related factors, and subsequent rotator cuff fatigue, may cause the subacromial space (the space between the inferior acromion surface and superior humerus) of the shoulder to decrease. Reducing this space can create impingement of the interposed tissues, which causes shoulder pain. The aim of this study was to examine superior humeral head excursion and changes in the width of the subacromial space (acromio-humeral interval) after fatiguing the rotator cuff musculature. Four anterior-posterior radiographs of the glenohumeral joint at arm abduction angles of 0˚, 45˚, 90˚ and 135˚ were taken before and after a fatiguing task. The fatiguing task was a simulated job task requiring shoulder flexion/abduction and internal/external rotation, with the intention of exhausting the entire rotator cuff. The position of the humeral head with respect to the glenoid cavity was significantly affected both by arm angle and fatigue state; the mean humeral superior excursion following fatigue was 0.63±1.76mm. In the pre-fatigued state, increasing arm angle was related to superior translation until 90˚, after which the humeral head moved inferiorly to a more central position. In the post-fatigued state, the inability of the rotator cuff to centralize the humeral head led to increasing translations with higher elevations. Although the magnitude of translation in this study was smaller than seen in patients with rotator cuff tears, continuous overhead work demonstrably created rotator cuff fatigue, which apparently inhibited the ability of the shoulder musculature to resist upward translation of the humerus. Therefore, jobs that require overhead and repetitive work arguably put the worker at greater risk for superior translation of the humerus and subsequent related tissue damage.

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.

Undesirable work factors, such as awkward upper body postures and repetitive arm motion, in the workplace can lead to upper extremity pain. Research suggests that these work-related factors, and subsequent rotator cuff fatigue, may cause the subacromial space (the space between the inferior acromion surface and superior humerus) of the shoulder to decrease. Reducing this space can create impingement of the interposed tissues, which causes shoulder pain. The aim of this study was to examine superior humeral head excursion and changes in the width of the subacromial space (acromio-humeral interval) after fatiguing the rotator cuff musculature. Four anterior-posterior radiographs of the glenohumeral joint at arm abduction angles of 0˚, 45˚, 90˚ and 135˚ were taken before and after a fatiguing task. The fatiguing task was a simulated job task requiring shoulder flexion/abduction and internal/external rotation, with the intention of exhausting the entire rotator cuff. The position of the humeral head with respect to the glenoid cavity was significantly affected both by arm angle and fatigue state; the mean humeral superior excursion following fatigue was 0.63±1.76mm. In the pre-fatigued state, increasing arm angle was related to superior translation until 90˚, after which the humeral head moved inferiorly to a more central position. In the post-fatigued state, the inability of the rotator cuff to centralize the humeral head led to increasing translations with higher elevations. Although the magnitude of translation in this study was smaller than seen in patients with rotator cuff tears, continuous overhead work demonstrably created rotator cuff fatigue, which apparently inhibited the ability of the shoulder musculature to resist upward translation of the humerus. Therefore, jobs that require overhead and repetitive work arguably put the worker at greater risk for superior translation of the humerus and subsequent related tissue damage.