A presente dissertação de mestrado teve como foco a avaliação dos aspectos biomecânicos, da coluna cervical e de exercícios do pescoço, associados à diminuição da ação dos flexores profundos e aumento da ação dos flexores superficiais. Estas mudanças nas ações musculares estão associadas a indivíduos com cervicalgia crônica e a investigação deste trabalho pode levar a uma melhor compreensão desta lesão e consequente melhor tratamento. Na busca desta meta foram desenvolvidos quatro estudos apresentados ao longo desta dissertação. Estudo 1: Uma revisão sistemática com metanálise comparando a capacidade de produção de força entre indivíduos com cervicalgia e indivíduos saudáveis. Para este estudo foram incluídos 20 artigos que compararam capacidade de produção de força entre os grupos, onde foi identificado que indivíduos com cervicalgia crônica apresentam menor capacidade de produção de força para flexão, extensão e flexão lateral direita e esquerda. Estudo 2: A partir do estudo 1 surgiu o estudo observacional desta dissertação o qual comparou a força dos flexores profundos e superficiais da coluna cervical e a força articular cervical durante exercícios de fortalecimento do pescoço através de um modelo biomecânico. Para este estudo 20 participantes foram avaliados durante exercícios dinâmicos e isométricos de flexão, extensão e flexão lateral direita. A carga do exercício foi definida em 15-25% da capacidade de produção de força pescoço e foram feitas 5 repetições para o exercício dinâmico e mantida por 10 segundos para o exercício isométrico. As forças musculares e articulares foram estimadas pelo modelo biomecânico Biomechanics of Bodies e as variáveis cinéticas e cinemáticas foram coletadas com o BTS Smart-DX. O exercício de flexão dinâmica apresentou os maiores valores de força para os flexores profundos ao mesmo tempo que os flexores superficiais não apresentaram diferenças entre a flexão isométrica e dinâmica. Estudo 3: Este estudo foi realizado visando dar maior segurança e robustez às respostas do modelo biomecânico do Estudo 2, correlacionando as respostas de força muscular, estimada com o modelo biomecânico, e a atividade muscular com eletromiógrafo, dos músculos esternocleidomastóides direito e esquerdo. As correlações se apresentaram em média excelentes tanto para o esternocleidomastoide direito (r=0.69±0.20) e esquerdo (r=0.71±0.22), estimulando a confiança nos resultados obtidos pelo modelo biomecânico para os músculos flexores profundos da cervical. Estudo 4: Este estudo avaliou diferentes métodos de contração voluntária isométrica máxima para normalizar o sinal eletromiográfico do esternocleidomastoide e escaleno anterior. Com base nos resultados deste estudo, o método proposto em flexão lateral com a cabeça rotada foi o que apresentou a maior ativação para o esternocleidomastoide e o método convencional a que apresentou a maior ativação para o escaleno anterior. Portanto é sugerido uma adaptação ao método apresentado na literatura para contração voluntária isométrica máxima do esternocleidomastoide. Com base nestes quatro estudos, podemos afirmar que indivíduos com cervicalgia apresentam menor capacidade de produção de força, mostrando a necessidade de exercícios de fortalecimento, além da função de hipoalgesia normal do exercício. Levando em conta a diminuição da força dos flexores profundos cervical e aumento da ativação dos flexores superficiais em indivíduos com cervicalgia crônica, o exercício de flexão cervical dinâmica parece ser o mais indicapado para o fortalecimento dos flexores profundos, ao mesmo tempo que reduz a ativação dos flexores superficiais. / The present dissertation focused on the evaluation of the biomechanical aspects of the cervical spine and neck exercises, associated to the decrease of the action of the deep flexors and increase of the action of the superficial flexors. These changes in muscular actions are associated with individuals with chronic neck pain and the investigation of this work can lead to a better understanding of this lesion and consequent better treatment. In the pursuit of this aim, four studies were developed through this dissertation. Study 1: A systematic review with metanalysis comparing neck strength between individuals with neck pain and healthy controls. For this study, 20 articles comparing neck strength between groups and it was found that individuals with chronic neck pain have lower neck strength in flexion, extension, right and left lateral flexion. Study 2: From the development of study 1 came the observational study which compared the superficial, deep neck flexor muscle force and joint force during neck strengthening exercises using a biomechanical model. For this study, 20 participants were evaluated during dynamic and isometric exercises of flexion, extension and right lateral flexion. The exercise load was defined as 15-25% of the neck strength and 5 repetitions were made for the dynamic exercise and maintained for 10 seconds for the isometric exercise. Muscle and joint forces were estimated with the biomechanical model the Biomechanics of Bodies, and the kinetic and kinematic variables were collected using BTS Smart-DX. The dynamic neck flexion exercise showed the highest deep neck flexors muscle force values at the same time that the superficial neck flexors did not present differences between the isometric and dynamic flexion. Study 3: This study was carried out aiming at giving greater safety and robustness to the responses of the biomechanical model of Study 2, correlating the muscular force responses, estimated with the biomechanical model, and the muscular activity with electromyograph, of the right and left sternocleidomastoid muscles. Correlations were on average high for both right sternocleidomastoid (r = 0.69 ± 0.20) and left (r = 0.71 ± 0.22), ensuring the results obtained by the biomechanical model for the deep neck flexor muscles. Study 4: This study evaluated different methods of maximal isometric voluntary contraction to normalize the electromyographic signal of the sternocleidomastoid and anterior scalene. Based on the results of this study, the method proposed performing a lateral flexion with a rotated head was the one that presented the highest activation for the sternocleidomastoid however the conventional method was the one that presented the highest activation for the anterior scalene. Therefore, we suggest an adaptation to the method presented in the literature for the maximum voluntary isometric contraction of the sternocleidomastoid. Based on these four studies, we can affirm that individuals with neck pain have a lower neck strength, showing the need for strengthening exercises, in addition to the normal hypoalgesia function of the exercise. Regarding the decreased deep neck flexors force and increased superficial neck flexors force in individuals with chronic neck pain, the dynamic neck flexion exercise it seems to be the most suitable for the strengthening of deep flexors, while reducing the activation of the superficial flexors.

A presente dissertação de mestrado teve como foco a avaliação dos aspectos biomecânicos, da coluna cervical e de exercícios do pescoço, associados à diminuição da ação dos flexores profundos e aumento da ação dos flexores superficiais. Estas mudanças nas ações musculares estão associadas a indivíduos com cervicalgia crônica e a investigação deste trabalho pode levar a uma melhor compreensão desta lesão e consequente melhor tratamento. Na busca desta meta foram desenvolvidos quatro estudos apresentados ao longo desta dissertação. Estudo 1: Uma revisão sistemática com metanálise comparando a capacidade de produção de força entre indivíduos com cervicalgia e indivíduos saudáveis. Para este estudo foram incluídos 20 artigos que compararam capacidade de produção de força entre os grupos, onde foi identificado que indivíduos com cervicalgia crônica apresentam menor capacidade de produção de força para flexão, extensão e flexão lateral direita e esquerda. Estudo 2: A partir do estudo 1 surgiu o estudo observacional desta dissertação o qual comparou a força dos flexores profundos e superficiais da coluna cervical e a força articular cervical durante exercícios de fortalecimento do pescoço através de um modelo biomecânico. Para este estudo 20 participantes foram avaliados durante exercícios dinâmicos e isométricos de flexão, extensão e flexão lateral direita. A carga do exercício foi definida em 15-25% da capacidade de produção de força pescoço e foram feitas 5 repetições para o exercício dinâmico e mantida por 10 segundos para o exercício isométrico. As forças musculares e articulares foram estimadas pelo modelo biomecânico Biomechanics of Bodies e as variáveis cinéticas e cinemáticas foram coletadas com o BTS Smart-DX. O exercício de flexão dinâmica apresentou os maiores valores de força para os flexores profundos ao mesmo tempo que os flexores superficiais não apresentaram diferenças entre a flexão isométrica e dinâmica. Estudo 3: Este estudo foi realizado visando dar maior segurança e robustez às respostas do modelo biomecânico do Estudo 2, correlacionando as respostas de força muscular, estimada com o modelo biomecânico, e a atividade muscular com eletromiógrafo, dos músculos esternocleidomastóides direito e esquerdo. As correlações se apresentaram em média excelentes tanto para o esternocleidomastoide direito (r=0.69±0.20) e esquerdo (r=0.71±0.22), estimulando a confiança nos resultados obtidos pelo modelo biomecânico para os músculos flexores profundos da cervical. Estudo 4: Este estudo avaliou diferentes métodos de contração voluntária isométrica máxima para normalizar o sinal eletromiográfico do esternocleidomastoide e escaleno anterior. Com base nos resultados deste estudo, o método proposto em flexão lateral com a cabeça rotada foi o que apresentou a maior ativação para o esternocleidomastoide e o método convencional a que apresentou a maior ativação para o escaleno anterior. Portanto é sugerido uma adaptação ao método apresentado na literatura para contração voluntária isométrica máxima do esternocleidomastoide. Com base nestes quatro estudos, podemos afirmar que indivíduos com cervicalgia apresentam menor capacidade de produção de força, mostrando a necessidade de exercícios de fortalecimento, além da função de hipoalgesia normal do exercício. Levando em conta a diminuição da força dos flexores profundos cervical e aumento da ativação dos flexores superficiais em indivíduos com cervicalgia crônica, o exercício de flexão cervical dinâmica parece ser o mais indicapado para o fortalecimento dos flexores profundos, ao mesmo tempo que reduz a ativação dos flexores superficiais. / The present dissertation focused on the evaluation of the biomechanical aspects of the cervical spine and neck exercises, associated to the decrease of the action of the deep flexors and increase of the action of the superficial flexors. These changes in muscular actions are associated with individuals with chronic neck pain and the investigation of this work can lead to a better understanding of this lesion and consequent better treatment. In the pursuit of this aim, four studies were developed through this dissertation. Study 1: A systematic review with metanalysis comparing neck strength between individuals with neck pain and healthy controls. For this study, 20 articles comparing neck strength between groups and it was found that individuals with chronic neck pain have lower neck strength in flexion, extension, right and left lateral flexion. Study 2: From the development of study 1 came the observational study which compared the superficial, deep neck flexor muscle force and joint force during neck strengthening exercises using a biomechanical model. For this study, 20 participants were evaluated during dynamic and isometric exercises of flexion, extension and right lateral flexion. The exercise load was defined as 15-25% of the neck strength and 5 repetitions were made for the dynamic exercise and maintained for 10 seconds for the isometric exercise. Muscle and joint forces were estimated with the biomechanical model the Biomechanics of Bodies, and the kinetic and kinematic variables were collected using BTS Smart-DX. The dynamic neck flexion exercise showed the highest deep neck flexors muscle force values at the same time that the superficial neck flexors did not present differences between the isometric and dynamic flexion. Study 3: This study was carried out aiming at giving greater safety and robustness to the responses of the biomechanical model of Study 2, correlating the muscular force responses, estimated with the biomechanical model, and the muscular activity with electromyograph, of the right and left sternocleidomastoid muscles. Correlations were on average high for both right sternocleidomastoid (r = 0.69 ± 0.20) and left (r = 0.71 ± 0.22), ensuring the results obtained by the biomechanical model for the deep neck flexor muscles. Study 4: This study evaluated different methods of maximal isometric voluntary contraction to normalize the electromyographic signal of the sternocleidomastoid and anterior scalene. Based on the results of this study, the method proposed performing a lateral flexion with a rotated head was the one that presented the highest activation for the sternocleidomastoid however the conventional method was the one that presented the highest activation for the anterior scalene. Therefore, we suggest an adaptation to the method presented in the literature for the maximum voluntary isometric contraction of the sternocleidomastoid. Based on these four studies, we can affirm that individuals with neck pain have a lower neck strength, showing the need for strengthening exercises, in addition to the normal hypoalgesia function of the exercise. Regarding the decreased deep neck flexors force and increased superficial neck flexors force in individuals with chronic neck pain, the dynamic neck flexion exercise it seems to be the most suitable for the strengthening of deep flexors, while reducing the activation of the superficial flexors.

Introduction: Musculoskeletal pain is a common problem in the working population. In Sweden, 40% of women and 30% of men report suffering from neck and shoulder pain weekly. The underlying cause for neck pain is often not known and the treatment is commonly guided by the individual’s symptoms. However, there is a lack of knowledge on how to receive the best effect based on the individual’s symptoms and functional limitations, and therefore this has been scarcely evaluated in research. Furthermore, the impact of work exposure and stress on long-term treatment for persons with neck pain is not clear. Aims: To develop (paper 1) and to evaluate a decision model for tailored treatment in women with neck pain (paper 2). Moreover, to determine if risk factors at work and stress influence intermediate and long-term treatment results (paper 3). Further, to investigate if changes in self-reported pain and disabilities are associated with changes of physical test outcomes of the neck and shoulder region after treatment (paper 4). Methods: In an RCT, 120 working women with non-specific neck pain were randomized to three different groups – tailored treatment (TT), non-tailored treatment (NTT) or treatment-as-usual (TAU) for an 11 weeks intervention with short-term, intermediate-term and long-term follow-ups. The TT group was guided by a decision model with cut-off levels to indicate impairments. The NTT group received two established treatment components randomly from those not indicated, and TAU group did not receive any treatment within the study. The RCT primary outcomes were self-reported neck pain and neck disability. A linear mixed model was used for analysing the effects. One week after the end of intervention work exposure and stress were assessed at a work-place visit and associations to treatment results were tested for, and mixed models were used to estimate longitudinal associations. Associations between self-reported neck problems and physical outcomes were estimated with univariate and multiple regressions analysis. Results: No differences between TT and NTT were revealed for neck pain and disability. In comparison to TAU, the TT and NTT groups both showed improvements at short-term follow-up, but not at intermediate and long-term follow-up. High stress level and low self-estimated control at work were associated with more pain and disability at the intermediate and long-term follow-ups. After intervention and at the intermediate-term follow-up, reduced neck pain, disability and frequency of symptoms were associated with increased peak speed of head rotation and cervical range of motion. Conclusion: Tailored treatment according to the decision model was not superior to the non-tailored treatment in women with non-specific neck pain. One explanation for this can be the weak relationships found between neck pain and disability and physical test outcomes. Further, perceived stress and psychosocial work exposure were associated with self-reported neck problems and should be taken into account to optimize the effects in neck pain rehabilitation. / Bakgrund: Nack- och skulder-smärta är ett vanligt tillstånd som förekommer över hela världen. I Sverige skattar 30-40% besvär från nacke och skuldror mätt under en veckas tid. Generellt rapporterar kvinnor mer nack- och skulder-besvär än män. I avhandlingen är det ospecifik nacksmärta som har studerats, det inkluderar inte t.ex. Whiplash-skador, diskbråck eller andra mer specifika diagnoser. Den bakomliggande orsaken till ospecifik nacksmärta är, precis som beteckningen antyder, ofta inte känd och individens symptom och funktion är istället vägledande i undersökning och behandling samt utvärdering av behandling. Studier har visat att i jämförelse med friska har individer med ospecifika nackbesvär ofta sämre muskulär nackstyrka, minskad rörlighet i nacken och är något långsammare vid test av huvudrörelser. Behandlingen riktar sig ofta mot något av dessa fynd med bl.a. styrketräning av nackmuskler och/eller manuella tekniker för rörelseökning. Studier har dock visat att behandlingen endast ger måttliga resultat och att de positiva resultaten bara är kortvariga. I kliniken försöker man individanpassa behandlingen utifrån patientens behov men det finns väldigt lite forskning om detta utan studier utvärderar likadan behandling för hela grupper. Det saknas fortfarande kunskaper om hur man på bästa sätt individanpassar behandling så att den blir skräddarsydd utifrån individens symptom och funktion samt utvärderar detta. Syftet med avhandlingen var att undersöka om en intervention med skräddarsydd behandling (som också innehöll specifik aktiv träning) utifrån en beslutsmodell med fysiska tester och frågor om symtom är effektivt för att uppnå positiva effekter i självskattad smärta och funktion (artikel 1 och 2).  Den skräddarsydda behandlingen jämfördes mot en grupp som fick samma upplägg men inte skräddarsydd behandling. Vidare undersöktes om båda dessa behandlingsgrupper var effektivare än en grupp som inte fick någon behandling i studien. Dessutom undersöktes om påverkan från arbetsmiljön i form av fysisk och psykosocial belastning samt upplevd stress påverkade behandlingsresultaten efter interventionen (artikel 3). Slutligen undersöktes om de fysiska testerna och den självskattade smärtan, funktionen och symptomen hade koppling till varandra dels före interventionen och dels i termer av förändringar efter interventionen (artikel 4). Metod: I en randomiserad kontrollerad interventionsstudie (RCT) inkluderades 120 kvinnor i åldrarna 20-65, alla i arbete, och som hade ospecifika nackbesvär.  De lottades till tre grupper, (1) skräddarsydd behandling (Tailore treatment, TT), (2) icke-skräddarsydd behandling (Non-tailored treatment, NTT) och (3) en kontrollgrupp (Treatment-as-usual, TAU) som inte fick någon behandling i studien men var fria att söka vård på egen hand. Kvinnorna i TT-gruppen fick behandlings-komponenter utifrån testresultaten i beslutsmodellen. Det kunde läggas till någon behandlingskomponent om det visade sig behövas utifrån individens behov i vardagen. Detta undersöktes genom en strukturerad intervju-teknik som kallas Problem Elicitation Technique (PET). Kvinnorna i NTT-gruppen fick två lottade behandlings-komponenter som inte matchade deras behov utifrån testerna i beslutsmodellen. För båda behandlings-grupperna var interventionen 11 veckor med inbokade behandlingstillfällen 2-3 gånger per vecka, samtliga tillfällen vägledda av fysioterapeut. Data för alla tre grupper samlades in innan interventionen samt 3, 9 och 15 månader efter start av interventionen. Gruppskillnaderna analyserades med en ”linear mixed model”. En vecka efter intervention gjordes ett arbetsplatsbesök hos individerna i alla tre grupper. En erfaren ergonom observerade individernas fysiska arbetsbelastning med ett ergonomiskt bedömningsinstrument, Quick Exposure Check (QEC), och individerna skattade också den psykosociala arbetsmiljön i ett frågeformulär, QPS Nordic, samt upplevd stress. För att undersöka om den fysiska och psykosociala arbetsbelastningen samt stress påverkade resultaten från interventionen analyserades data med linjär regression och mixed model. För att undersöka om de fysiska testerna och den självskattade smärtan, funktionen och symptomen hade något samband användes linjär regressionsanalys. Resultat: Att skräddarsy behandlingen utifrån den testade beslutsmodellen var inte effektivare än att inte skräddarsy. I jämförelse med kontrollgruppen självskattade båda behandlingsgrupperna mindre smärta, bättre funktion och mindre symptom efter interventionen. I de länge uppföljningarna (9 och 15 månader) var dock skillnaderna mellan grupperna inte längre signifikanta förutom att båda behandlingsgrupperna, till skillnad från kontrollgruppen, upplevde sig bättre än innan behandling. Det visade sig att upplevd hög stressnivå och låg kontroll på arbetet hade samband med mer självskattad nacksmärta, sämre funktion och lägre arbetsproduktivitet. De fysiska testerna och självskattade nackbesvär hade bara svaga samband. På baslinjenivå, innan interventionen, fanns det samband mellan hög nackstyrka och låg självskattad funktion och låg frekvens på symptomen, samt mellan att vara långsam i testet av snabba huvudrörelser och hög smärta. Efter interventionen hade individernas förändring i självskattad smärta fortfarande bara samband med snabba huvudrörelser. Förbättring i självskattad funktion och symptom hade samband till ökad hastighet i snabba huvudrörelser och ökat rörelseutslag nackrotation. Sammanfattning: För kvinnor i arbete med ospecifika nackbesvär var det inte mer effektivt att skräddarsy behandling/träning utifrån en beslutsmodell jämfört med att slumpmässigt välja ut behandlingskomponenter från samma behandlingsarsenal. En förklaring kan vara att det fanns endast låga samband mellan självskattad smärta och funktion och de fysiska testerna. Upplevd stress och kontroll i arbetet visade sig ha samband med självskattad smärta, funktion och arbetsproduktivitet och bör tas i beaktande i framtida interventioner för individer med nacksmärta.

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published_or_final_version / Pathology / Master / Master of Medical Sciences

A dissertation presented in partial fulfillment of the requirements for the Master's Degree in Technology: Chiropractic, Technikon Natal, 1997. / The purpose of this study was to determine the effectiveness of the spinous push versus the transverse process contact rotary type adjustments in the treatment of sub-acute and chronic mechanical upper thoracic and neck pain. It was hypothesized that both adjustments, over a maximum of nine treatments with two treatments per week and a further four week follow-up period, would be effective in terms of improving the patients' cervical ranges of motion, vertebral pressure pain threshold levels and their perceptions of pain and disability. The study design was a randomized, un-blinded, un-controlled comparative group study with a sample population consisting of thirty consecutive patients (Ave. age 35.4 years; M:F 16: 14) suffering from joint dysfunction of the cervical or upper thoracic spine. Each group received one adjustment two times a week for a maximum of nine treatments. Soft tissue therapy was employed in each treatment as a pre-adjustment procedure. The objective data collected was goniometrically assessed cervical range of motion and algometrically assessed vertebral pressure pain thresholds. The subjective data was collected by means of the CMCC Neck Disability, the Short Form McGill Pain and the Numerical Pain Rating Scale-l0 1 Questionnaires. / M

Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Technikon Natal, 2001. / Neck pain is a common condition that has become a serious health concern. Since there is controversy regarding the most effective management of this condition, further research needs to be executed. The purpose of this investigation was to compare manipulation combined with a cervical pillow to manipulation alone in the management of mechanical neck pain. The rationale behind this, was that manipulation is one of the most common treatments for spinal conditions and has shown significant results in alleviating mechanical neck pain. Cervical pillows have been investigated by various researchers. They have concluded that cervical pillows are effective in treating mechanical neck pain. Thus, using the pillow as an adjunct to manipulation should attain superior results to manipulation alone. This study consisted of 40 patients who were randomly divided into 2 equal groups. The average age of the patients was 34 years old and the average duration of neck pain was pain of greater than 6 months. The patients received 6 treatments over a 4 week period. Group1 were manipulated and given a cervical pillow to sleep on, while group 2 received manipulation alone. / M

Mini-dissertation in partial compliance with the requirements for the Masters Degree in Technology: Chiropractic, Durban Institute of Technology, 2005. / According to the recent literature the application of non-steroidal anti-inflammatory drugs (NSAIDS) is the mainstay and first line of conventional treatment for many types of pain, including that of spinal origin (DiPalma and DiGregorio 1994; Dabbs and Lauretti 1995; Koes et al. 1997). NSAID therapy has inherent side effects (Goodman and Simon 1994), however, given the risks involved, they are still of value as an adjunct to spinal manipulation (Crawford 1988), which has been shown to have less side effects and be more effective than conventional NSAIDS (Dabbs and Lauretti 1995; Giles and Müller 1999). A homeopathic alternative to NSAIDS is Traumeel S, it fulfils all the criteria for a locally acting therapeutic medication, with promotion of the natural healing process, and minimum side effects (Zell et al. 1989). A study by Hepburn (2000) compared the relative efficacy of Traumeel S against NSAIDS in the treatment of cervical facet syndrome. Hepburn concluded that there was statistically no difference between the two therapies. It could therefore be inferred that Traumeel S may be a valid alternative to NSAID therapy in the treatment of cervical facet syndrome. This study tested this hypothesis by comparing the effectiveness of spinal manipulation with the concurrent administration of oral Traumeel S against spinal manipulation alone in order to assess the potential benefit of combining Traumeel S with manipulation. / M

The purpose of this study was to estimate the CTV-PTV margin required for prostate and head and neck cancer treatments at the radiotherapy departments of Karolinska University Hospital.    Portal image data from patients treated at the radiotherapy departments during the period of 2009-2011 was used to estimate the set-up displacements for each treatment area. By using the acquired images the magnitude of the systematic, i.e. preparatory, and random, i.e. execution, error was determined in the anterior-posterior (AP), superior-inferior (SI) and right-left (RL) direction. The calculated PTV margin is based on the systematic and random errors of the entire patient populations. A total of 40 patients were used for the analysis of prostate treatments and 47 patients for head and neck treatments. The evaluation of the PTV margin was done for three different matching protocols; no matching (skin marker alignment), five day matching and daily matching.      With no image verification in prostate treatments the calculated PTV margin taking both inter- and intrafractional errors into account was 13.6, 9.2 and 7.9 mm in AP, SI, and RL direction respectively. The corresponding PTV margin in head and neck treatments was found to be 6.7, 5.3 and 4.9 mm. Using a five day matching protocol of the bony anatomy showed no considerable reductions in margins for neither prostate nor head and neck treatments. With daily matching of the bony anatomy in prostate treatments the calculated margins was reduced to 8.1, 7.9 and 2.4 mm in the AP, SI and RL direction respectively.  Measurements of the residual deviations of individual cervical vertebrae after daily image verification and correction in head and neck cancer treatments showed that all matching protocols will require larger margins in the lower vertebrae in order to account for the set-up error in the AP direction. The corresponding margins needed using daily matching of the bony anatomy would be 3.9, 5.4 and 6.0 mm for C1, C4 and C5 respectively in the AP direction.    In the absence of daily imaging the currently used PTV margins might be inadequate for covering to movement of the targets. The deviations in the AP direction of the cervical vertebrae in head and neck cancer treatments should be investigated further in order to ensure that the motion of the target is covered and that no risk organs are subjected to harmful dose levels.

Thesis (M.Tech.:Chiropractic)-Dept. of Chiropractic, Durban Institute of Technology, 2005 xii, [137] leaves / Musculoskeletal injuries in computer users are an increasing concern. The computer has become an essential working tool that is used throughout all levels of companies and organisations. Management and professional personnel are required to use computers, often without training in typing skills, this combined with higher stress and responsibility levels and lengthy work hours. Potentially this makes them a high-risk group for work related injury. Previous research has focused mainly on data entry and secretarial workers, who are often competent in typing and keyboard skills. There is an increasing body of literature that implicates a wide variety of factors responsible for computer and office related musculoskeletal injury, however there is still much conflict as to what factors play the most influential role in development of these disorders. Conflict largely remains over the role of individual and constitutional factors versus workplace factors such as ergonomic design and patterns of computer use. The aim of this study was therefore to determine the prevalence of and related risk factors associated with work related musculoskeletal injuries of the neck and shoulder in non-secretarial computer users within the South African context.