The purpose of this study was to determine the effectiveness of a modified sitting position straight leg raise on vastus medialis oblique (VMO) strength and EMG activity as compared to a traditional straight leg raise. A total of twenty-three subjects were recruited for this study. The subjects were randomly assigned to one of the following groups: (group I) modified straight leg raise (MSLR), and (group II) straight leg raise (SLR). The exercise program was three weeks long. University procedures for the protection of human subjects were followed. The subjects began with a 5 minute warm-up on a Cybex stationary bike set at 90 revolutions / minute. The subject then had electrodes placed on the Vastus Lateralis (VL) and Vastus Medialis Oblique (VMO). A Macintosh computer was used to record the EMG data. The subject then performed a standard Cybex test for knee flexion and extension. The Cybex dynamometer was placed at the knee joint line, the chair back tilt was at 85 degrees, the hip, chest, and thigh restraints were all fastened. The subjects in group I (Modified sitting SLR) and II (SLR) then returned the next day for their first rehabilitation lesson. Each subject group then participated in their respected exercise program for a total of three weeks. After three weeks of rehabilitation, the subjects retested using the same procedures followed in the pretest. A two tailed t-test was used to determine significance of the difference between means of the two groups. No significant differences were found between the two groups. / School of Physical Education

The purpose of this study was to examine differences in drop landing ground reaction forces between athletes with and without patellar tendinitis. Subjects included 30 recreational athletes, 15 with patellar tendinitis and 15 without. Subjects with patellar tendinitis were tested twice, before (PTI) and after (PTF) rehabilitation. The non-patellar tendinitis (NPT) group was tested once. Subjects performed three trials of a drop landing from a height of 40 cm onto the force plate. Video data was collected to determine the deepest angle of knee flexion during landing. Statistical analysis using ANOVA revealed significant differences in maximum vertical force for the initial peak, post hoc analysis revealed differences between PTI and NPT groups aswell as between PTF and NPT groups. Results indicate athletes with patellar tendinitis exhibit higher initial peak 1 VGRF than athletes without patellar tendinitis. Results indicate that athletes who consistently land with elevated peak 1 ground reaction force are more likely to develop patellar tendinitis. / School of Physical Education

The purpose of this study was to determine the vastus medialis oblique muscular electromyographical (EMG) activity during two therapeutic exercises: the modified straight leg raise and the traditional straight leg raise. Two subject groups of 10 subjects each, one with anterior knee pain (PHY) and the other group with no history of patellofemoral pathology (NORM), performed the traditional straight leg raise (SLR) and a modified straight leg raise with external hip rotation (MOD). Each subject performed an isometric maximum voluntary contraction and three trials of each of the two therapeutic exercises. The EMG variables analyzed were the percent of the maximum voluntary contraction for each muscle, vastus medialis oblique, vastus lateralis, and rectus femoris: the percent of the maximum voluntary contraction of the ratio between the vastus medialis oblique and the vastus lateralis; the percent of the maximum voluntary contraction for the integrated EMG for each muscle; and the percent of the maximum voluntary contraction for the root mean square for each muscle. The statistical analysis was conducted with two-way analysis of variance procedures. The statistical analysis revealed no significant differences; however, the data appeared to illustrate a trend toward more electromyographical activity in the vastus medialis oblique in the PHY subject group during the MOD therapeutic exercise. This suggests that the MOD therapeutic exercise may be able to isolate the vastus medialis oblique muscle in persons with anterior knee pain and allow them to regain strength and normal function earlier than with the use of the SLR therapeutic exercise. / School of Physical Education

The primary purpose of this study was to determine the ratio of activation between the VMO and VL while performing three selected knee exercises (drop squat, modified lateral squat, Muncie Method). Additionally, the data was analyzed to determine if a correlation existed between the muscle's activation rate per set and whether or not the rates are affected by Q-angle or gender. Twenty Ball State University subjects (10 male, 10 female) who were asymptomatic to Patellofemoral Syndrome (PFS), provided electroymyographic (EMG) data while performing the three selected exercises. A one-way ANOVA found no statistical significance (p=0.500) on any of the tested variables except the Drop Squat VL Root Mean Square (RMS). Significant correlations were found between: VL RMS to set number during drop squat, and VMO and VL RMS to set number during Muncie Method performance. Based on the results of this study, each of these exercises could be used to selectively strengthen the VMO in treatment of PFS. / School of Physical Education

Patellofemoral pain (PFP) is believed to be associated with deficits in coordination between the different heads of the quadriceps muscle; however, considerable debate exists in the literature regarding the presence of such a deficit. Discrepancies between studies may be explained by differences in experimental tasks, such as whether the task is performed with open (OKC) or closed kinetic chain (CKC), or whether the activity is voluntary or triggered. Particular interest has been directed toward the function of the vastus medialis obliquus (VMO), which is a short muscle with limited ability to exert torque across the knee joint, but probably has a particular role in controlling patellofemoral joint position. Another short muscle that may influence knee joint position control is popliteus (POP), which is located in the back of the knee. This thesis investigates task specific activity of quadriceps in CKC versus OKC and studies the relative activity between the four heads of the quadriceps in PFP subjects compared to controls without knee pain in voluntary activity (CKC and OKC) and postural responses to balance perturbations. In addition, this thesis investigates the presumed function of POP for control of joint position in postural tasks in healthy individuals. All subjects were of normal weight and height and between 18 and 40 years. Quadriceps activity was tested for isometric with identical joint configuration in CKC and OKC, and it was performed as a reaction time task. Balance perturbations were elicited by unpredictable anterior and posterior translations of the support surface. Function of POP was investigated in unpredictable support surface translations and in self induced provocations to balance by moving the arms. Muscle activity was recorded with electromyography (EMG). Optic kinematic analysis was used to obtain specific movement responses to perturbations of balance. The quadriceps muscles were activated differently in CKC and OKC. VMO was activated earlier and to a greater degree in CKC. Rectus femoris was activated earlier and to a greater degree in OKC. PFP subjects reacted slower in both CKC and OKC, but there was no difference between groups in the relative activity between the different heads of the quadriceps. In the unpredictable support surface translation in the anterior direction, PFP subjects responded with earlier onset of VMO and with greater trunk and hip flexion in the anterior translation. POP activation in response to support surface translations in both directions occurred before all other muscles measured. In the self-initiated provocations of balance, POP was activated after the initiation of the balance provocation. This thesis concludes that quadriceps activity was task specific. The lack of difference between groups in OKC and CKC, and the difference between groups in postural responses suggest that variations in motor behaviour may occur only in tasks habitually performed. Differences in muscle activation patterns may be related to compensatory strategies to unload the quadriceps muscles and the patellofemoral joint. Furthermore, this thesis suggests that POP muscle may have a particular role in active control of the knee joint.

A síndrome da dor patelofemoral (SDPF) é o diagnóstico mais comum em populações fisicamente ativas. A SDPF está relacionada com o mau alinhamento dos membros inferiores durante tarefas de descarga de peso, causando maior estresse e dor na articulação patelofemoral. Esse mau alinhamento está relacionado com um aumento da inclinação ipsilateral do tronco, adução do quadril, abdução do joelho e maior grau de rotação interna da tíbia durante atividades dinâmicas, como agachamento unipodal, corrida, salto e subir e descer escadas. Fatores anatômicos e biomecânicos estão relacionados a alterações ao redor da articulação femoropatelar, como menor força de extensão do joelho, atraso na ativação do vasto medial em relação ao vasto lateral e atrofia do músculo quadríceps. Recentemente, alterações do quadril (fatores proximais), tornozelo e pé (fatores distais) têm sido propostas como fatores contribuintes da SDPF. No entanto, as evidências sobre ativação e alteração da morfologia muscular dos membros inferiores, principalmente nos fatores proximais e distais, são escassas. Esta tese teve como objetivo verificar as alterações neuromusculares dos membros inferiores e determinar se algum parâmetro neuromuscular explicava a cinemática durante tarefas unipodais. Após a apresentação dos motivos para realização deste estudo (Capítulo I), no Capítulo II objetivamos verificar as alterações neuromusculares (ativação muscular e morfologia muscular) relacionadas aos fatores proximais e distais na SDPF por meio de uma revisão sistemática. As buscas foram realizadas nas bases de dados Medline (via PubMed), Scielo, Scopus, PEDro, Cochrane Central, Embase e ScienceDirect databases até abril de 2018 para estudos avaliando ativação muscular ou parâmetros de morfologia muscular das articulações do tronco, quadril e tornozelo/pé. Dois revisores independentes avaliaram cada trabalho para inclusão e qualidade. Dezenove estudos foram identificados (SDPF, n = 319; GC, n = 329). Três estudos investigaram os músculos ao redor das articulações do tronco e tornozelo/pé. Quinze estudos investigaram os músculos ao redor da articulação do quadril. As evidências foram inconclusivas sobre a ativação do transverso do abdome/oblíquo interno (TrA/OI) na SDPF durante atividades de alta velocidade. Os níveis de ativação, duração e atraso na ativação de Glúteo Médio (GMed), glúteo máximo (GMax), biceps femoral (BF) and semitendinoso (ST) foram inconclusivos nos estudos incluídos. Não foram observadas diferenças na ativação de gastrocnêmio lateral (GL), gastrocnêmio medial (GM), sóleo (SOL), tibial anterior (TA) e fibular longo (FIB). Apenas um estudo incluído avaliou parâmetros da morfologia muscular, sem alterações na espessura muscular e na intensidade do eco GMed e GMax. Com base na falta de evidências sobre alterações na ativação muscular em torno das articulações do quadril, tornozelo e pé durante tarefas dinâmicas, e no fato de que um único estudo avaliou os resultados da morfologia muscular (GMed e GMax) na SDPF, propusemos um artigo original (Capítulo III) que teve como objetivo comparar os parâmetros neuromusculares dos membros inferiores e a cinemática no plano frontal durante tarefas unipodais de descarga de peso em mulheres com SDPF e determinar se algum resultado neuromuscular explicava o índice dinâmico de valgo (IVD) durante as tarefas. As buscas foram realizadas nas bases de dados Medline (via PubMed), Scielo, Scopus, PEDro, Cochrane Central, Embase e ScienceDirect databases até abril de 2018 para estudos avaliando ativação muscular ou parâmetros de morfologia muscular das articulações do tronco, quadril e tornozelo/pé. Dois revisores independentes avaliaram cada trabalho para inclusão e qualidade. Dezenove estudos foram identificados (SDPF, n = 319; GC, n = 329). Três estudos investigaram os músculos ao redor das articulações do tronco e tornozelo/pé. Quinze estudos investigaram os músculos ao redor da articulação do quadril. As evidências foram inconclusivas sobre a ativação do transverso do abdome/oblíquo interno (TrA/OI) na SDPF durante atividades de alta velocidade. Os níveis de ativação, duração e atraso na ativação de Glúteo Médio (GMed), glúteo máximo (GMax), biceps femoral (BF) and semitendinoso (ST) foram inconclusivos nos estudos incluídos. Não foram observadas diferenças na ativação de gastrocnêmio lateral (GL), gastrocnêmio medial (GM), sóleo (SOL), tibial anterior (TA) e fibular longo (FIB). Apenas um estudo incluído avaliou parâmetros da morfologia muscular, sem alterações na espessura muscular e na intensidade do eco GMed e GMax. Com base na falta de evidências sobre alterações na ativação muscular em torno das articulações do quadril, tornozelo e pé durante tarefas dinâmicas, e no fato de que um único estudo avaliou os resultados da morfologia muscular (GMed e GMax) na SDPF, propusemos um artigo original (Capítulo III) que teve como objetivo comparar os parâmetros neuromusculares dos membros inferiores e a cinemática no plano frontal durante tarefas unipodais de descarga de peso em mulheres com SDPF e determinar se algum resultado neuromuscular explicava o índice dinâmico de valgo (IVD) durante as tarefas. Quinze mulheres com SDPF e quinze mulheres saudáveis pareadas por 5 idade (grupo controle - GC) foram comparadas com os seguintes testes: (1) questionário funcional; (2) espessura muscular ao redor do quadril (GMed e tensor da fáscia lata - TFL), joelho (VL e VM) e tornozelo/pé (TA e FIB); (3) IVD e ativação muscular durante agachamento e salto vertical unipodais; (4) torque isométrico máximo para abdução do quadril, extensão do joelho e eversão/ inversão do pé; e (5) ativação muscular durante testes isométricos e funcionais. Uma regressão linear múltipla (modelo Stepwise) foi usada para verificar se alguma variável neuromuscular explicava o IVD durante as tarefas unipodais. O tamanho de efeito (ES) foi usado para determiner a magnitude da diferença entre os grupos. Comparado ao GC, o grupo SDPF apresentou: (1) menor espessura do GMed (-10.02%; ES = -0.82) e maior espessura do TFL (+18.44%; ES = +0.92) e do FIB (+14.23%; ES = +0.87); (2) menor ativação do TA durante o agachamento unipodal (-59,38%; ES = -1.29); (3) menor ativação do GMed durante o salto vertical unipodal (-28.70%; ES = -1.35) e (4) maior ativação do GMed durante o teste isométrico de abdução de quadril (+34.40%; ES = +0.77). IVD durante o agachamento unipodal foi explicado pela ativação do VL durante a tarefa somente no GC, enquanto a espessura do TA no GC e o torque de eversores do pé no SDPF explicou o IVD durante o salto vertical unipodal. Com base em nossos resultados, as mulheres com SDPF apresentaram alterações neuromusculares significativas nas articulações do quadril e tornozelo/pé. No entanto, apenas fatores distais explicaram o IVD no grupo SDPF. / Patellofemoral pain syndrome (PFPS) is the most common diagnoses in physically active populations. PFPS is related with lower limbs poor alignment during weight-bearing tasks, causing higher patellofemoral joint stress and pain. This poor alignment is related with an increase of ipsilateral trunk lean, hip adduction, knee abduction and greater tibial internal rotation during dynamic activities such as single-leg squat, running, jumping, and stepping tasks. Anatomical and biomechanical factors are related with unwanted changes around the patellofemoral joint, such as lower knee extension strength, delayed onset of vastus medialis activation relative to vastus lateralis and quadriceps muscle atrophy (knee joint muscles intrinsic changes). Recently, hip (proximal), ankle and foot (distal) changes have been proposed as PFPS contributing factors. However, the evidences about lower limb muscle activation and morphology changes, mainly in proximal and distal factors, are scarce. This thesis aimed to create clinical subgroups based in lower limb neuromuscular changes and determine if some neuromuscular outcome explained kinematics during single-leg tasks. After displaying the reasons to perform this study (Chapter I), in Chapter II we aimed to verify neuromuscular changes (muscle activation and muscle morphology) related to proximal and distal factors in PFPS through a systematic review. Medline (via PubMed), Scielo, Scopus, PEDro, Cochrane Central, Embase and ScienceDirect databases were searched until April 2018 only for retrospective studies evaluating muscle activation or muscle morphology parameters of trunk, hip and ankle/foot joints. Two independent reviewers assessed each paper for inclusion and quality. Twenty retrospective studies were identified (PFPS, n=319; CG, n=329). Three studies investigated muscles around trunk and ankle/foot joints. Fifteen studies investigated muscles around the hip joint. Evidences were inconclusive about transversus abdominis/internal oblique (TrA/IO) activation in PFPS during high-speed activities. Gluteus medius (GMed), gluteus maximus (GMax), bíceps femoris (BF) and semitendinous (ST) activation level, activation duration and activation onset were inconclusive in the included studies. No differences were observed in gastrocnemius lateralis (GL), gastrocnemius medialis (GM), soleus (SOL), tibialis anterior (TA) and fibularis (FIB) muscle activation. Only one included study evaluated muscle morphology parameters, without changes in the GMed and GMax muscle thickness and echo intensity. Based in the lack of evidences about muscle activation changes in PFPS patients’ muscles around hip, ankle and foot joints during dynamic tasks, and in the fact that a single study evaluated muscle morphology outcomes (GMed), we proposed an original article (Chapter III) that aimed to compare lower limb neuromuscular parameters and frontal plane kinematics during single-leg tasks in women with PFPS, and determine if some neuromuscular outcome explained dynamic valgus index (DVI) during tasks. Fifteen PFPS women and fifteen healthy age-matched women (control group - CG) were compared with the following tests: (1) functional questionnaire; (2) hip (GMed and tensor fasciae latae - TFL), knee (VL and VM) and ankle/foot (TA and FIB) muscle thickness; (3) DVI and muscle activation during single-leg squat and vertical jump; (4) maximal isometric torque for hip abduction, knee extension and foot eversion/inversion; and (5) muscle activation during isometric and functional tests. A multiple- 7 stepwise regression analysis was used to test if neuromuscular outcomes explained DVI during single-leg tasks. Effect sizes (ES) were used to determine the magnitude of between-groups differences. Compared to the CG, PFPS showed: (1) smaller GMed (-10.02%; ES = -0.82) and greater TFL (+18.44%; ES = +0.92) and FIB muscle thickness (+14.23%; ES = +0.87); (2) lower TA muscle activation during single-leg squat (-59,38%; ES = -1.29); (3) lower GMed muscle activation during single-leg jump (-28.70%; ES = -1.35) and (4) greater GMed muscle activation during hip abduction isometric test (+34.40%; ES = +0.77). DVI during single-leg squat was explained by VL activation during this task only in CG, whereas lower TA muscle thickness in the CG and higher foot eversion torque in PFPS explained DVI during single-leg vertical jump. Based in our results, females with PFPS showed significant neuromuscular changes at the hip and ankle/foot joints. However, only distal factors explained DVI in the PFPS group.

The Gluteus Medius and the Tensor Fascia Lata are two of the main muscles involved in the action of hip abduction. This action is important for both dynamic movements in athletic pursuits and in every day ambulation. Weakness in these muscles has been connected to multiple injuries in the lower limb, but the question of the casual relationship between gait change, hip abductor weakness, and lower limb injury is still up for debate. As presented by the current research, younger populations tend to have overuse injuries with females having a greater susceptibility for injuries connected to hip abductor weakness, and older populations tend to have injures related to atrophy and degeneration of either the hip abductor muscles or the joint surrounding the hip. Research in this field has increasingly focused on sub-sets of the populations, such as just females or just males, trying to pinpoint the role that hip abductor weakness plays in these injuries. By trying to minimize or even eliminate the confounding variables that have previously made it difficult to determine the role hip abductor weakness plays in these gait changes and injuries, these studies have been able to make more clear conclusions at the expense of making a broader generalization. Similarities and differences between how the sub-groups present with hip abductor weakness are discussed, as well as discrepancies observed within the research done on similar cohorts. Future directions for research in this field are discussed, as well as implications for clinical implementation of targeted rehabilitation programs to ensure the best possible outcomes.

A síndrome da dor patelofemoral (SDPF) é o diagnóstico mais comum em populações fisicamente ativas. A SDPF está relacionada com o mau alinhamento dos membros inferiores durante tarefas de descarga de peso, causando maior estresse e dor na articulação patelofemoral. Esse mau alinhamento está relacionado com um aumento da inclinação ipsilateral do tronco, adução do quadril, abdução do joelho e maior grau de rotação interna da tíbia durante atividades dinâmicas, como agachamento unipodal, corrida, salto e subir e descer escadas. Fatores anatômicos e biomecânicos estão relacionados a alterações ao redor da articulação femoropatelar, como menor força de extensão do joelho, atraso na ativação do vasto medial em relação ao vasto lateral e atrofia do músculo quadríceps. Recentemente, alterações do quadril (fatores proximais), tornozelo e pé (fatores distais) têm sido propostas como fatores contribuintes da SDPF. No entanto, as evidências sobre ativação e alteração da morfologia muscular dos membros inferiores, principalmente nos fatores proximais e distais, são escassas. Esta tese teve como objetivo verificar as alterações neuromusculares dos membros inferiores e determinar se algum parâmetro neuromuscular explicava a cinemática durante tarefas unipodais. Após a apresentação dos motivos para realização deste estudo (Capítulo I), no Capítulo II objetivamos verificar as alterações neuromusculares (ativação muscular e morfologia muscular) relacionadas aos fatores proximais e distais na SDPF por meio de uma revisão sistemática. As buscas foram realizadas nas bases de dados Medline (via PubMed), Scielo, Scopus, PEDro, Cochrane Central, Embase e ScienceDirect databases até abril de 2018 para estudos avaliando ativação muscular ou parâmetros de morfologia muscular das articulações do tronco, quadril e tornozelo/pé. Dois revisores independentes avaliaram cada trabalho para inclusão e qualidade. Dezenove estudos foram identificados (SDPF, n = 319; GC, n = 329). Três estudos investigaram os músculos ao redor das articulações do tronco e tornozelo/pé. Quinze estudos investigaram os músculos ao redor da articulação do quadril. As evidências foram inconclusivas sobre a ativação do transverso do abdome/oblíquo interno (TrA/OI) na SDPF durante atividades de alta velocidade. Os níveis de ativação, duração e atraso na ativação de Glúteo Médio (GMed), glúteo máximo (GMax), biceps femoral (BF) and semitendinoso (ST) foram inconclusivos nos estudos incluídos. Não foram observadas diferenças na ativação de gastrocnêmio lateral (GL), gastrocnêmio medial (GM), sóleo (SOL), tibial anterior (TA) e fibular longo (FIB). Apenas um estudo incluído avaliou parâmetros da morfologia muscular, sem alterações na espessura muscular e na intensidade do eco GMed e GMax. Com base na falta de evidências sobre alterações na ativação muscular em torno das articulações do quadril, tornozelo e pé durante tarefas dinâmicas, e no fato de que um único estudo avaliou os resultados da morfologia muscular (GMed e GMax) na SDPF, propusemos um artigo original (Capítulo III) que teve como objetivo comparar os parâmetros neuromusculares dos membros inferiores e a cinemática no plano frontal durante tarefas unipodais de descarga de peso em mulheres com SDPF e determinar se algum resultado neuromuscular explicava o índice dinâmico de valgo (IVD) durante as tarefas. As buscas foram realizadas nas bases de dados Medline (via PubMed), Scielo, Scopus, PEDro, Cochrane Central, Embase e ScienceDirect databases até abril de 2018 para estudos avaliando ativação muscular ou parâmetros de morfologia muscular das articulações do tronco, quadril e tornozelo/pé. Dois revisores independentes avaliaram cada trabalho para inclusão e qualidade. Dezenove estudos foram identificados (SDPF, n = 319; GC, n = 329). Três estudos investigaram os músculos ao redor das articulações do tronco e tornozelo/pé. Quinze estudos investigaram os músculos ao redor da articulação do quadril. As evidências foram inconclusivas sobre a ativação do transverso do abdome/oblíquo interno (TrA/OI) na SDPF durante atividades de alta velocidade. Os níveis de ativação, duração e atraso na ativação de Glúteo Médio (GMed), glúteo máximo (GMax), biceps femoral (BF) and semitendinoso (ST) foram inconclusivos nos estudos incluídos. Não foram observadas diferenças na ativação de gastrocnêmio lateral (GL), gastrocnêmio medial (GM), sóleo (SOL), tibial anterior (TA) e fibular longo (FIB). Apenas um estudo incluído avaliou parâmetros da morfologia muscular, sem alterações na espessura muscular e na intensidade do eco GMed e GMax. Com base na falta de evidências sobre alterações na ativação muscular em torno das articulações do quadril, tornozelo e pé durante tarefas dinâmicas, e no fato de que um único estudo avaliou os resultados da morfologia muscular (GMed e GMax) na SDPF, propusemos um artigo original (Capítulo III) que teve como objetivo comparar os parâmetros neuromusculares dos membros inferiores e a cinemática no plano frontal durante tarefas unipodais de descarga de peso em mulheres com SDPF e determinar se algum resultado neuromuscular explicava o índice dinâmico de valgo (IVD) durante as tarefas. Quinze mulheres com SDPF e quinze mulheres saudáveis pareadas por 5 idade (grupo controle - GC) foram comparadas com os seguintes testes: (1) questionário funcional; (2) espessura muscular ao redor do quadril (GMed e tensor da fáscia lata - TFL), joelho (VL e VM) e tornozelo/pé (TA e FIB); (3) IVD e ativação muscular durante agachamento e salto vertical unipodais; (4) torque isométrico máximo para abdução do quadril, extensão do joelho e eversão/ inversão do pé; e (5) ativação muscular durante testes isométricos e funcionais. Uma regressão linear múltipla (modelo Stepwise) foi usada para verificar se alguma variável neuromuscular explicava o IVD durante as tarefas unipodais. O tamanho de efeito (ES) foi usado para determiner a magnitude da diferença entre os grupos. Comparado ao GC, o grupo SDPF apresentou: (1) menor espessura do GMed (-10.02%; ES = -0.82) e maior espessura do TFL (+18.44%; ES = +0.92) e do FIB (+14.23%; ES = +0.87); (2) menor ativação do TA durante o agachamento unipodal (-59,38%; ES = -1.29); (3) menor ativação do GMed durante o salto vertical unipodal (-28.70%; ES = -1.35) e (4) maior ativação do GMed durante o teste isométrico de abdução de quadril (+34.40%; ES = +0.77). IVD durante o agachamento unipodal foi explicado pela ativação do VL durante a tarefa somente no GC, enquanto a espessura do TA no GC e o torque de eversores do pé no SDPF explicou o IVD durante o salto vertical unipodal. Com base em nossos resultados, as mulheres com SDPF apresentaram alterações neuromusculares significativas nas articulações do quadril e tornozelo/pé. No entanto, apenas fatores distais explicaram o IVD no grupo SDPF. / Patellofemoral pain syndrome (PFPS) is the most common diagnoses in physically active populations. PFPS is related with lower limbs poor alignment during weight-bearing tasks, causing higher patellofemoral joint stress and pain. This poor alignment is related with an increase of ipsilateral trunk lean, hip adduction, knee abduction and greater tibial internal rotation during dynamic activities such as single-leg squat, running, jumping, and stepping tasks. Anatomical and biomechanical factors are related with unwanted changes around the patellofemoral joint, such as lower knee extension strength, delayed onset of vastus medialis activation relative to vastus lateralis and quadriceps muscle atrophy (knee joint muscles intrinsic changes). Recently, hip (proximal), ankle and foot (distal) changes have been proposed as PFPS contributing factors. However, the evidences about lower limb muscle activation and morphology changes, mainly in proximal and distal factors, are scarce. This thesis aimed to create clinical subgroups based in lower limb neuromuscular changes and determine if some neuromuscular outcome explained kinematics during single-leg tasks. After displaying the reasons to perform this study (Chapter I), in Chapter II we aimed to verify neuromuscular changes (muscle activation and muscle morphology) related to proximal and distal factors in PFPS through a systematic review. Medline (via PubMed), Scielo, Scopus, PEDro, Cochrane Central, Embase and ScienceDirect databases were searched until April 2018 only for retrospective studies evaluating muscle activation or muscle morphology parameters of trunk, hip and ankle/foot joints. Two independent reviewers assessed each paper for inclusion and quality. Twenty retrospective studies were identified (PFPS, n=319; CG, n=329). Three studies investigated muscles around trunk and ankle/foot joints. Fifteen studies investigated muscles around the hip joint. Evidences were inconclusive about transversus abdominis/internal oblique (TrA/IO) activation in PFPS during high-speed activities. Gluteus medius (GMed), gluteus maximus (GMax), bíceps femoris (BF) and semitendinous (ST) activation level, activation duration and activation onset were inconclusive in the included studies. No differences were observed in gastrocnemius lateralis (GL), gastrocnemius medialis (GM), soleus (SOL), tibialis anterior (TA) and fibularis (FIB) muscle activation. Only one included study evaluated muscle morphology parameters, without changes in the GMed and GMax muscle thickness and echo intensity. Based in the lack of evidences about muscle activation changes in PFPS patients’ muscles around hip, ankle and foot joints during dynamic tasks, and in the fact that a single study evaluated muscle morphology outcomes (GMed), we proposed an original article (Chapter III) that aimed to compare lower limb neuromuscular parameters and frontal plane kinematics during single-leg tasks in women with PFPS, and determine if some neuromuscular outcome explained dynamic valgus index (DVI) during tasks. Fifteen PFPS women and fifteen healthy age-matched women (control group - CG) were compared with the following tests: (1) functional questionnaire; (2) hip (GMed and tensor fasciae latae - TFL), knee (VL and VM) and ankle/foot (TA and FIB) muscle thickness; (3) DVI and muscle activation during single-leg squat and vertical jump; (4) maximal isometric torque for hip abduction, knee extension and foot eversion/inversion; and (5) muscle activation during isometric and functional tests. A multiple- 7 stepwise regression analysis was used to test if neuromuscular outcomes explained DVI during single-leg tasks. Effect sizes (ES) were used to determine the magnitude of between-groups differences. Compared to the CG, PFPS showed: (1) smaller GMed (-10.02%; ES = -0.82) and greater TFL (+18.44%; ES = +0.92) and FIB muscle thickness (+14.23%; ES = +0.87); (2) lower TA muscle activation during single-leg squat (-59,38%; ES = -1.29); (3) lower GMed muscle activation during single-leg jump (-28.70%; ES = -1.35) and (4) greater GMed muscle activation during hip abduction isometric test (+34.40%; ES = +0.77). DVI during single-leg squat was explained by VL activation during this task only in CG, whereas lower TA muscle thickness in the CG and higher foot eversion torque in PFPS explained DVI during single-leg vertical jump. Based in our results, females with PFPS showed significant neuromuscular changes at the hip and ankle/foot joints. However, only distal factors explained DVI in the PFPS group.

Submitted by Livia Mello (liviacmello@yahoo.com.br) on 2016-09-13T18:31:05Z No. of bitstreams: 1 DissDAS.pdf: 724792 bytes, checksum: 6e6dc2ee847f8b606d1db59ff59b6679 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-15T13:30:09Z (GMT) No. of bitstreams: 1 DissDAS.pdf: 724792 bytes, checksum: 6e6dc2ee847f8b606d1db59ff59b6679 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-15T13:30:19Z (GMT) No. of bitstreams: 1 DissDAS.pdf: 724792 bytes, checksum: 6e6dc2ee847f8b606d1db59ff59b6679 (MD5) / Made available in DSpace on 2016-09-15T13:30:26Z (GMT). No. of bitstreams: 1 DissDAS.pdf: 724792 bytes, checksum: 6e6dc2ee847f8b606d1db59ff59b6679 (MD5) Previous issue date: 2016-02-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / The reduction in dorsiflexion has been related to the presence of movement patterns in the knee and hip potentially injurious the patellofemoral joint in various tasks. However, no studies have evaluated the association during running. The aim of this study was to investigate the association between the range of ankle dorsiflexion and the kinematics of the hip, knee and ankle during the stance phase of the running. Were recruited 39 healthy runners of both genders and aged between 18 and 35 years. The evaluation of ankle dorsiflexion amplitude was performed by lunge test. The kinematics of the running on a treadmill was performed using the Qualisys motion capture system. Pearson correlation was performed to evaluate the association between the range of ankle dorsiflexion and kinematic variables. Three kinematic variables were significantly associated with the range of ankle dorsiflexion: peak knee flexion (r = .510, p = .001), peak lateral rotation of the knee (r = -.527, p = .001) and peak ankle dorsiflexion (r= .377, p = .022). Whereas the decreased knee flexion and ankle dorsiflexion, and the increase in lateral rotation of the knee, increase the burden on the patellofemoral joint, limitation of ankle dorsiflexion range may be related to the origin of patellofemoral pain in runners. / A redução da dorsiflexão tem sido relacionada à presença de padrões de movimento no joelho e quadril potencialmente lesivos à articulação patelofemoral em diversas tarefas. Entretanto, nenhum estudo avaliou esta associação durante a corrida. O objetivo do presente estudo foi verificar a associação entre a amplitude de dorsiflexão do tornozelo e a cinemática do quadril, joelho e tornozelo durante a fase de apoio da corrida. Foram recrutados 39 corredores saudáveis de ambos os gêneros e com idades entre 18 e 35 anos. A avaliação da amplitude de dorsiflexão do tornozelo foi realizada por meio do lunge test. A avaliação cinemática da corrida em esteira ergométrica foi realizada utilizando o sistema de captura de movimento Qualisys. Correlação de Pearson foi realizada para avaliar a associação entre a amplitude de dorsiflexão do tornozelo e as variáveis cinemáticas. Três variáveis cinemáticas foram significativamente associadas com a amplitude de dorsiflexão do tornozelo: pico de flexão do joelho (r = .510; p = .001), pico de rotação lateral do joelho (r = -.527; p = .001) e o pico de dorsiflexão do tornozelo (r = .377; p = .022). Considerando que a diminuição da flexão do joelho e da dorsiflexão do tornozelo, bem como o aumento na rotação lateral do joelho, aumentam o a sobrecarga na articulação patelofemoral, a limitação da amplitude de dorsiflexão do tornozelo pode estar relacionada à origem da dor patelofemoral em corredores.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introduction: Patellofemoral pain syndrome (PFPS) is a condition that affects young women and it can contribute to lower limb functionality reduction. However, while some studies demonstrate functional alterations related to this syndrome, others do not find this difference between individuals with and without this condition. Objectives: To evaluate and compare the level of pain and functionality, muscular recruitment, joint position sense and dynamic postural control between young women with and without PFPS. Metodologia: 12 women with PFPS (21.67 ± 2.49 of age) and 12 controls (21.25 ± 2.01) participated in this study. Self-perceived knee functionality was assessed by Lysholm Knee Scoring Scale and the level of pain by Visual Analogue Scale (VAS). Electromyography (EMG) evaluated lateral gastrocnemius, soleus (SO), tibialis anterior, vastus medialis oblique (VMO), vastus medialis longus, vastus lateralis (VL) and bíceps femoris muscles during stair ascent and descent of different heights (5 e 15cm), the results was analyzed in 3 phases. Joint position sense was assessed by electrogoniometer and dynamic postural control was assessed by the Star Excursion Balance Test (SEBT).. Statistic analyzes compared the two groups by student t for independent samples and Mann-Whitney tests. The results are expressed as mean ± standard deviation. Results: There was difference (p<0,001) between groups in VAS (SDFP: 5,08 ± 1,98, GC: 0 ± 0,0;) and Lysholm Scale (GC: 99,62 ± 1,38, SDFP: 68,33 ± 16,08). Just the phase 1 (p=0,041) and 3 (p=0,035) of soleus muscle showed difference during descent of 5cm step. Phase 2 of VL (p=0,020), 3 of VMO (p=0,005) and VL (p=0,016) also showed difference during ascent of 15 cm step. There was no difference (p>0,05) between groups in joint position sense and SEBT. Conclusion: Women with PFPS report higher pain and lower knee functionality than controls. However, they do not demonstrate altered joint position sense and dynamic postural control, and could need of higher quadriceps recruitment during stair ascent. / Introdução: A Síndrome da Dor Femoropatelar (SDFP) é uma condição que afeta mulheres jovens e pode contribuir para a redução da funcionalidade do membro inferior. Entretanto, enquanto alguns estudos demonstram alterações funcionais relacionadas à SDFP, outros não encontram diferenças entre portadores e não portadores. Objetivos: Avaliar e comparar o nível de dor, funcionalidade, o recrutamento muscular, o senso de posição articular e o controle postural dinâmico entre mulheres jovens portadoras e não portadoras da SDFP. Metodologia: 12 mulheres com SDFP (21,67 ± 2,49 anos de idade) e 12 controles (21,25 ± 2,01) participaram do estudo. A autopercepção da funcionalidade do joelho foi acessada pelo questionário de Lysholm e o nível de dor por meio da Escala Visual Analógica (EVA). Foi realizada a eletromiografia (EMG) dos músculos gastrocnêmico lateral, sóleo (SO), tibial anterior, vasto medial oblíquo (VMO), vasto medial longo, vasto lateral (VL) e bíceps femoral durante a subida e descida de dois degraus de alturas diferentes (5 e 15cm), os resultados foram analisados em 3 fases dinstintas. A avaliação do senso de posição articular foi realizada por meio do eletrogoniômetro e o controle postural dinâmico por meio do Star Excursion Balance Test (SEBT). A análise estatítisca comparou os dois grupos por meio dos testes t de student para amostras independentes e Mann-Whitney. Os resultados foram expressos como média ± desvio padrão. Resultados: Houve diferença (p<0,001) entre os grupos na EVA (SDFP: 5,08 ± 1,98, GC: 0 ± 0,0;) e no questionário de Lysholm (GC: 99,62 ± 1,38, SDFP: 68,33 ± 16,08). Apenas a fase 1 (p=0,041) e fase 3 (p=0,035) do músculo SO apresentou diferença na decida do degrau de 5cm, e a fase 2 do VL (p=0,020), fase 3 do VMO (p=0,005) e VL (p=0,016) na subida do degrau de 15 cm. Não houve diferença significativa (p>0,05) no senso de posição articular e SEBT. Conclusão: Mulheres com SDFP relatam maior dor e menor funcionalidade na articulação do joelho. Entretanto, as mesmas não possuem senso de posição articular e controle postural dinâmico alterado, mas podem necessitar de maior recrutamento do quadríceps durante a subida de degraus. / Mestre em Ciências da Saúde