No description available.

No / Modification of high-risk movement strategies such as dynamic knee valgus is key to the reduction of anterior cruciate ligament (ACL) and patellofemoral joint (PFJ) injuries. Augmented feedback, which includes video and verbal feedback, could offer a quick, simple and effective alternative to training programs for altering high-risk movement patterns. It is not clear whether feedback can reduce dynamic knee valgus measured using frontal plane projection angle (FPPA). Methods Vertical ground reaction force (vGRF), two-dimensional FPPA of the knee, contact time and jump height of 20 recreationally active university students were measured during a drop jump task pre- and post- an augmented feedback intervention. A control group of eight recreationally active university students were also studied at baseline and repeat test. Results There was a significant reduction in vGRF (p = 0.033), FPPA (p < 0.001) and jump height (p < 0.001) and an increase in contact time (p < 0.001) post feedback in the intervention group. No changes were evident in the control group. Conclusion Augmented feedback leads to significant decreases in vGRF, FPPA and contact time which may help to reduce ACL and PFJ injury risk. However, these changes may result in decreased performance. Clinical relevance Augmented feedback reduces dynamic knee valgus, as measured via FPPA, and forces experienced during the drop jump task and therefore could be used as a tool for helping decrease ACL and PFJ injury risk prior to, or as part of, the implementation of injury prevention training programs.

Mini-dissertation submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, 2012. / Purpose: Patellofemoral Pain Syndrome is a common condition in all age groups, with a multifactorial etiology. This study aimed to investigate the association between the Quadriceps femoris muscle group, Hamstring muscle group and Adductor muscle group, and to establish the relationship between myofascial trigger points (MFTP’s) in these muscle groups and patellofemoral pain syndrome (PFPS). Methods: A cross-sectional, observational, quantitative non-intervention clinical assessment study was conducted at the Chiropractic Day Clinic at Durban University of Technology (DUT), to determine the extent of the PFPS, the MFTPs and thus the relationship between the two. The study included eighty patients with PFPS, who were recruited by convenience sampling. The results were captured using Microsoft excel and SPSS version 15.0 was used to analyze the data. Results: Quadriceps femoris muscle group MFTPs were noted in 92.5% of the patients (most prevalent being Vastus medialis TP1 (63.8%), Vastus lateralis TP1 (33.8%) and Vastus intermedius at 27,5%). Least common was Vastus lateralis TP2 only presenting in 2,5% of the patients. Hamstring muscle group MFTPs were found overall in 86.3% of patients (most prevalent being in Biceps femoris muscle (66%), and least prevalent being in Semitendinosus muscle (11,3%)). MFTPs were present in 64% overall of the Adductor muscle group (Adductor magnus muscle being the most common). Significant associations were made between the presence of MFTPs in the Vastus lateralis TP2 (p=0.00), Vastus medialis TP1 (p=0.046; 0.005; 0.004), the NRS and the PPSS. Also significant was the relationship between the NRS, PPSS and the Semimembranosus and Adductor magnus muscles indicated that these muscles were the most likely causes of pain even though they had fewer MFTPs than other comparable muscles. Conclusion: The outcomes of this study supports previous research indicating that an extensor dysfunction of the Quadriceps femoris muscle group may be of MFTP origin and indicates that other muscles in the thigh require further research indicating their role in the development of PFPS.

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The shape of the knee’s trochlear groove is a very important factor in the overall stability of the knee. However, a quantitative description of the normal three-dimensional geometry of the trochlea is not available in the literature. This is also reflected in the poor outcomes of patellofemoral arthroplasty (PFA). In this study, a standardised method for femoral parameter measurements on three-dimensional femur models was established. Using software tools, virtual femur models were aligned with the mechanical and the posterior condylar planes and this framework was used to measure the femoral parameters in a repeatable way. An artificial neural network (ANN), incorporating the femoral parameter measurements and classifications done by experienced surgeons, was used to classify knees into normal and abnormal categories. As a result, 15 knees in the database were classified by the ANN as being normal. Furthermore, the geometry of the normal knees was analysed by fitting B-spline curves and circular arcs on their sagittal surface curves to prove and reconfirm that the groove has a circular shape on a sagittal plane. Self-organising maps (SOM), which is a type of ANN, was trained with the acquired data of the normal knees and in this way the normal trochlear geometry could be predicted. The prediction of the anterior-posterior (AP) distance and the trochlear heights showed an average agreement of 97 % between the actual and the predicted normal geometries. A case study was conducted on four types of trochlear dysplasia to determine a normal geometry for these knees, and a virtual surface reconstruction was performed on them. The study showed that the trochlea was deepened after the surface reconstruction, having an average trochlea depth of 5.5 mm compared to the original average value of 2.9 mm. In summary, this research proposed a quantitative method for describing and predicting the normal geometry of a knee by making use of ANN and the femoral parameters that are unaffected by trochlear dysplasia. / AFRIKAANSE OPSOMMING: Die vorm van die trogleêre keep is ’n belangrike faktor in patella-stabiliteit. Tog is ’n kwantitatiewe beskrywing van die normale driedimensionele geometrie van die troglea nog nie beskikbaar nie, wat duidelik blyk uit die swak uitkomste van patellofemorale artroplastie (PFA). In hierdie studie is ’n gestandaardiseerde metode vir die meting van femorale parameters op grond van driedimensionele femurmodelle ontwikkel. Die femurmodel is in lyn gebring met die meganiese en posterior kondilêre vlak, welke raamwerk gebruik is om die femorale parameters op ’n herhaalbare wyse te meet. Die normale knieë is geklassifiseer met ’n kunsmatige neurale netwerk (ANN), wat die femorale parameter-mate sowel as die chirurgiese klassifikasie ingesluit het, en 15 knieë is gevolglik as normaal aangewys. Die normaleknie-geometrie is ontleed deur B-latkrommes en sirkelboë op die sagittale oppervlak-kurwes aan te bring om te bewys en te herbevestig dat die keep uit ’n sirkelvorm op ’n sagittale vlak bestaan. Die ingesamelde data van die normale knieë is ingevoer by selfreëlende kaarte (SOM), synde ’n soort ANN, wat die navorser in staat gestel het om die normale trogleêre geometrie te voorspel. Die voorspelling van die anterior-posterior (AP) afstand en die trogleêre hoogtes toon ’n gemiddelde ooreenkoms van meer as 97 % tussen die werklike en voorspelde normale geometrie. ’n Gevallestudie is op vier soorte trogleêre displasie uitgevoer om die normale geometrie te voorspel en ’n oppervlakrekonstruksie daarop uit te voer. Hierdie studie het getoon dat die troglea ná oppervlakrekonstruksie verdiep was, met ’n gemiddelde trogleadiepte van 5.5 mm in vergelyking met die aanvanklike gemiddelde waarde van 2.9 mm. Hierdie navorsing het dus ’n metode aan die hand gedoen vir die kwantitatiewe beskrywing en voorspelling van normale geometrie met behulp van ANN sowel as met die femorale parameters wat nie deur die trogleêre displasie geraak word nie.

Introdução: A síndrome da dor patelofemoral (SDP) é uma das condições musculoesqueléticas mais comum de dor anterior no joelho. Caracteriza-se pela dor e crepitação durante atividades funcionais diárias como agachar, subir e descer escada, dentre outras. Apesar da alta incidência, os mecanismos e causas ainda são pouco compreendidos. Teoriza-se que o déficit dos músculos do quadril contribui para o desenvolvimento da SDP e alteração do controle postural. Objetivo: Comparar o controle postural estático e dinâmico em mulheres com e sem a síndrome patelofemoral. O objetivo secundário é verificar a correlação do controle postural com a força dos músculos do quadril no grupo SDP. Métodos: Foram avaliadas 50 mulheres divididas em dois grupos: Síndrome da dor patelofemoral (SDP) (n=25) e Controle (GC) (n=25). O controle postural estático e dinâmico foram avaliados na plataforma de força Balance Master Neurocom System, utilizando dois testes: a) apoio unipodal (estático) b) subir/descer um degrau (dinâmico) para a mensuração do centro de pressão. As forças isométricas dos músculos extensores, abdutores e rotadores laterais do quadril foram avaliados com o dinamômetro manual; a dor com a escala visual analógica (EVA) e a funcionalidade pela escala de atividades de vida diária (EAVD). No Grupo SDP foi avaliado o membro sintomático ou o mais sintomático para a SDP bilateral, e no controle o membro dominante. Resultados: O grupo da SDP apresentou déficit do controle postural estático em relação ao controle, com maior oscilação do COP no apoio unipodal: área [4,92 ± 1,54 vs 3,55 ± 1,07], deslocamento ântero-posterior [3,49 ± 0,60 vs 3,10 ± 0,93], deslocamento médio-lateral [2,22 ± 0,32 vs 1,9 ± 0,44], velocidade total [8,41 ± 1,43 vs 7,24 ± 1,20], velocidade ântero-posterior [7,75 ± 1,33 vs 6,53 ± 1,15] com diferença estatisticamente significante (p<0.05). No controle dinâmico apresentou maior oscilação: área [155,23 ± 23,94 vs 137,94 ± 25,82], deslocamento médio-lateral [32,3 ± 5,5 vs 21,7 ± 2,7] e velocidade médio-lateral [22,2 ± 2,05 vs 17,0 ± 1,6] e (p < 0.05). O grupo SDP apresentou força isométrica diminuída para os músculos extensores, abdutores, rotadores laterais do quadril (p < 0.05) comparado ao grupo controle. No controle postural dinâmico do grupo SDP foi encontrada correlação positiva do deslocamento e velocidade ântero-posterior com os músculos extensores do quadril [r = 0,42 e 0,54] Conclusão: Indivíduos com a síndrome da dor patelofemoral apresentam déficit do controle postural estático e dinâmico, da força dos extensores, abdutores e rotadores laterais do quadril. O déficit de força dos extensores do quadril foi associado ao aumento da oscilação do COP no controle dinâmico / Background: Patellofemoral pain syndrome (PFP) is one of the most common musculoskeletal conditions of anterior knee pain. It is characterized by pain and crepitus during daily functional activities such as squatting, going up and down stairs and others activities. Despite the high incidence, the mechanism and causes are poor understood. It is theorized that the deficit of the hip muscles contributes to the development of the PFP and changes in postural control. Objective: To compare the static and dynamic postural control in females with and without patelofemoral pain syndrome and secondary objective was to verify the correlation of postural control with hip strength muscles in PFP group. Methods: Fifty females were divided on two groups: patellofemoral pain syndrome (PFP) (n = 25) and Control (CG) (n =25). The static and dynamic postural control was assessed on the Balance Master force Neurocom System platform, using two tests: a) one single leg (static) b) step up/down (dynamic) for the measurement of pressure center. The isometric strength of the hip extensor muscles, abductors and external rotators were assessed with hand-held dynamometer; pain with a visual analogue scale (VAS); the functionality by the activities daily life scale (ADLS). In PFP was evaluated symptomatic or more symptomatic for bilateral and the dominant limb for control group. Results: The PFP group showed deficits in static postural control compared to control group, with greater COP oscillation on the leg support : area [ 4.92 ± 1.54 vs 3.55 ± 1.07 ], anterior-posterior displacement [ 3.49 ± 0.60 vs 3.10 ± 0.93 ] , medial-lateral displacement [ 2.22 ± 0.32 vs 1.9 ± 0.44 ] , total velocity [ 8.41 ± 1.43 vs 7.24 ± 1.20 ], anterior-posterior velocity [ 7.75 ± 1.33 vs 6.53 ± 1.15 ] was statistically significant (p < 0,05 ). In dynamic control showed greater COP oscillation: area [155.23 ± 23.94 vs 137.94 ± 25.82], medial-lateral displacement [32.3 ± 5.5 vs. 21.7 ± 2.7] medial-lateral velocity [22.2 ± 2.05 vs 17.0 ± 1.6] and (p < 0.05). The PFP group had decreased in hip isometric strength of the extensors abductors, lateral rotators muscles, compared to the control group (p < 0.05). The PFP group showed a positive correlation of anterior- posterior displacement and velocity with the hip extensor muscles [r = 0.42 and 0.54]. Conclusion: Females with patellofemoral pain syndrome have deficit in static and dynamic postural control; hip extensors, abductors and external rotators strength. The deficit of the hip extensor muscle was associated with increased oscillation in the dynamic control of COP

A síndrome da dor patelofemoral é uma disfunção do joelho comum entre mulheres jovens fisicamente ativas que causa limitações na atividade física e atividades de vida diária, podendo evoluir para a artrite patelofemoral. Este estudo verificou a influência da síndrome da dor patelofemoral nos movimentos e coordenação dos membros inferiores e avaliou os efeitos agudos de uma intervenção cinesioterapêutica em indivíduos com síndrome da dor patelofemoral no descer escada. O Estudo 1 comparou a intensidade da dor, os movimentos, os padrões de coordenação e a variabilidade de coordenação dos membros inferiores de indivíduos com e sem a síndrome da dor patelofemoral durante o descer escada. A cinemática 3D do joelho, tornozelo e multisegmentar do pé foi comparada entre 30 mulheres adultas jovens, 16 com síndrome da dor patelofemoral e 14 controles. Os padrões e a variabilidade da coordenação foram comparados entre os grupos utilizando uma análise do vetor codificado. A escala visual analógica de dor (EVA) foi utilizada para analisar a intensidade da dor. O Estudo 2 verificou os efeitos imediatos de uma intervenção cinesioterapêutica na intensidade da dor e nos movimentos dos membros inferiores de indivíduos com síndrome da dor patelofemoral no descer escada. O grupo com síndrome da dor patelofemoral foi dividido em grupo intervenção cinesioterapêutica (n=8) e grupo controle (n=8). A cinemática 3D e a intensidade da dor (EVA) durante o descer escada foram analisadas antes e depois da intervenção. O Estudo 1 mostrou que a síndrome da dor patelofemoral está relacionada à menor inversão do antepé nas fases iniciais do descer escada e que a intensidade da dor aumenta durante a descida de escada. Os padrões de coordenação do membro inferior mostraram estratégias de restrição da flexão do joelho, assim como restrição da mobilidade do pé em indivíduos com síndrome da dor patelofemoral. Este estudo não confirmou que a menor variabilidade da coordenação está relacionada à síndrome da dor patelofemoral. O Estudo 2 mostrou que uma sessão de intervenção cinesioterapêutica é capaz de modificar os movimentos do tornozelo e pé, consequentemente modificando o movimento do joelho no plano sagital. A intervenção cinesioterapêutica diminui a dor durante a descida de escada em indivíduos com síndrome da dor patelofemoral. Estudos são necessários para a comprovação da eficácia clínica da intervenção cinesioterapêutica em médio e longo prazos / Patellofemoral pain syndrome is one of the most common dysfunctions of the knee among physical active young women. This knee dysfunction can limit physical activity as well as daily living activities. Patellofemoral pain syndrome can also lead to patellofemoral arthritis. This study aimed to verify the influence of patellofemoral pain on the lower extremity movements and coordination as well as verify the acute effects of a kinesiotherapy intervention on the lower extremity of individuals with patellofemoral pain during stair descent. On the first study, we compared the pain intensity, the lower extremity movements, coordination patterns and coordination variability between participants with and without patellofemoral pain during stair descent. 3D kinematics of the knee, ankle and multisegmental of the foot were compared between 30 adult young women, 16 with and 14 without patellofemoral pain. The coordination patterns and variability were compared between groups using a modified vector coding technique.The pain intensity was analized using a visual analogic pain scale (VAS). The second study aimed to verify the acute effects of an intervention on the pain intensity and lower extremity movements in participants with patellofemoral pain during stair descent. The participants with patellofemoral pain (n=16) were divided into two groups, intervention group (n=8) and control group (n=8). We analized the 3D kinematics and pain intensity (VAS) before and after the intervention. The outcome measures of the first study show that patellofemoral pain is associated with less forefoot inversion during the support phase of stair descent. Besides that, the pain intensity increases during stair descent in participants with patellofemoral pain. The coordination patterns show strategies of knee flexion constrain as well as mobility constrain of the foot in individuals with patellofemoral pain. The coordination variability was not associated with patellofemoral pain in this study. The second study shows that the intervention can imediatelly modify the foot, ankle and knee movements and decrease the patellofemoral pain during stair descent. Future studies should address the intervention effectiveness in medium and long- term

Introdução: A síndrome da dor patelofemoral (SDP) é definida como queixa dolorosa na região anterior do joelho, mais comumente na face medial da patela. Teoriza-se que o déficit de força dos músculos estabilizadores do quadril e do controle dinâmico do membro inferior esteja relacionado com o desenvolvimento da SDP. Objetivos: O objetivo primário foi comparar o ângulo de projeção no plano frontal (APPF) do joelho e a força isométrica dos músculos do quadril e tronco em indivíduos com e sem SDP. O objetivo secundário foi analisar a correlação do APPF com a força dos músculos do quadril e tronco. Métodos: A amostra foi composta por 43 mulheres, divididas em dois grupos: Dor Patelofemoral (GDP, n = 22) e Controle (GC, n = 21). A força dos músculos abdutores, rotadores laterais e extensores do quadril e flexão lateral de tronco (Core lateral) foram avaliados com um dinamômetro isométrico. A avaliação da força foi bilateral para calcular o Índice de Simetria entre os Membros (ISM). O complexo póstero-lateral do quadril foi calculado pela soma dos três grupos musculares do quadril divido por três. O APPF foi avaliado com uma câmera digital durante step down em três desfechos: a) Inicial: antes de iniciar o movimento; b) Final: ao final do movimento de step down; e c) Final-Inicial: diferença entre os ângulos inicial e final. Para análise do APPF foi utilizado o Software de Avaliação Postural (SAPo). Resultados: O GDP apresentou APPF Final e Final-Inicial 5,2º maior que o GC. Em relação à força dos músculos do quadril, foi constatado um déficit no GDP em comparação ao controle para os abdutores (10,4 ± 3,3 vs 12,7 ± 2,7, P = 0,02), extensores (14,2 ± 7,1 vs 18,9 ± 5,9, P = 0,02), rotadores laterais (11,6 ± 3,1 vs 13,5 ± 2,4, P = 0,03) e complexo póstero-lateral (12,1 ± 3,8 vs 15,1 ± 2,8, P = 0,01) do quadril. O GDP apresentou maior assimetria entre os membros em relação à força dos músculos do quadril e tronco. A assimetria entre os membros variou entre 13,1 a 22,6% no GDP e 1,8 a 3,3% no GC (P < 0,05). No GDP, a força dos músculos rotadores laterais e do complexo póstero-lateral do quadril apresentou boa correlação negativa com o APPF Final-Inicial (r = -0,4). No GC, o APPF Final e Final-Inicial apresentaram boa correlação negativa com o índice de simetria dos músculos abdutores, força dos rotadores laterais e do complexo póstero-lateral do quadril (r > -0,4). Além disso, no APPF Final-Inicial foi encontrada correlação negativa com a força dos músculos abdutores (r = -0,42). Conclusão: Os dados indicam que mulheres com dor patelofemoral apresentam maior APPF do joelho, déficit de força dos abdutores, rotadores laterais, extensores e do complexo póstero-lateral do quadril e assimetria dos músculos do quadril e tronco. O déficit de força, principalmente dos rotadores laterais e do complexo póstero-lateral do quadril, está associado com o aumento do APPF do joelho / Introduction: The Patellofemoral Pain Syndrome (PFPS) is characterized by anterior knee pain, most commonly in the medial patellar facet. Reduced hip-stabilizers strength and dynamic control of lower limb might be related to the development of the PFPS. Objectives: The primary objective was to compare the Frontal Plane Projection Angle (FPPA) of the knee and hip and trunk strength in women with and without PFPS. The secondary objective was to analyze the relationship between FPPA with hip and trunk strength. Methods: The sample consisted of 43 women divided into two groups: Patellofemoral Group (PFG, n = 22) e Control Group (CG, n = 21). Muscle strength for hip-abduction, hip- extension, hip external- rotation extensors and lateral trunk-flexion (Core lateral) were measured bilaterally using a handheld dynamometer. The limb symmetry index (LSI) was calculated for all subjects. Hip posterolateral complex was calculated as the sum of the three hip muscles assessed divided by three. The FPPA was recorded by a digital camera during step down in three outcomes: a) Initial: before starting the movement; b) Final: in the end of the step down; and c) Final-Initial: difference between the final and initial angles. For FPPA analysis was used the Postural Assessment Software (PAS/SAPo). Results: FPPA Final and Final-Initial for the PFG reveal 5.2º greater than the CG (P < .05). Regarding the hip muscle strength, women with PFPS demonstrated deficit compared to the control group for hip abduction (10.4 ± 3.3 vs 12.7 ± 2.7, P = .02), hip extension (14.2 ± 7.1 vs 18.9 ± 5.9, P = .02), hip external rotation (11.6 ± 3.1 vs 13.5 ± 2.4, P = .03) and hip posterolateral complex (12.1 ± 3.8 vs 15.1 ± 2.8, P = .01). LSI values in women with PFPS were significantly worse than the control group. The hip and trunk asymmetry ranged from 13.1 to 22.6% in the PFG and 1.8 to 3.3% in the CG (P < .05). In the PFG, the hip-abduction and hip posterolateral complex strength showed moderate negative correlation with FPPA Final-Initial (r = -.4). In the CG, the LSI hip-abduction, hip-abduction and hip posterolateral complex strength showed moderate negative correlation with FPPA Final e Final-Initial (r > -.4). In addition, the hip-abduction strength deficit was associated with increased FPPA Final-Initial (r = -.42). Conclusion: The results indicate that women with patellofemoral pain demonstrate increased FPPA of the knee, weakness in hip-abduction, hip- extension, hip external- rotation, extensors and hip posterolateral complex. Women with patellofemoral showed most asymmetry of the hip and trunk muscle strength. The hip weakness, mainly hip external- rotation and posterolateral complex, is associated with increased FPPA of the knee

The ability to kneel is an important function of the knee joint, as it is required for many daily activities, including religious practices, professional occupations and recreational pursuits. The inability to kneel following total knee arthroplasty (TKA) is frequently a source of disappointment. This work investigates patients' understanding of the term 'kneeling' and what proportion of patients can kneel before and after TKA, as well as identifying the factors that can affect the ability to kneel following TKA. The underlying hypothesis tested was: 'There are no differences between kneeling ability before and after TKA'. Kneeling ability after TKA may be affected by many factors, including patient-specific factors, the extent of wear on RPC (Retro patellar Cartilage), postoperative AKP (Anterior Knee Pain) and post-operative ROM (Range of Motion). Thus a consecutive series of TKA patients were assessed to test the afore-mentioned hypothesis. In particular, the thesis has examined: • Interpretation of kneeling and perceptions of kneeling ability after TKA. • The extent of wear on Retro Patellar Cartilage (RPC) and its correlation to kneeling ability. • Sensory changes in the knee after TKA. • Preoperative and Postoperative Anterior Knee Pain (AKP) assessment. • The reality of kneeling ability before and after TKA. • Postoperative ROM of the knee and its correlation to kneeling function. The advice offered by healthcare professionals may contribute to a low postoperative rate of kneeling. The patellofemoral joint plays an essential role in knee function and a person's kneeling ability, may be greatly affected by the performance of this joint. Firstly, this study analysed the responses of two samples of participants drawn from diverse cultural backgrounds (Christian and Muslim), it examined their primary interpretation of what kneeling constitutes, along with a subjective assessment of the importance of kneeling in their everyday lives. Secondly, it explored patients' perceptions of their kneeling ability after TKA, with a comparative analysis of their responses to the kneeling questionnaire specifically constructed by the author and also the question in relation to kneeling in the Oxford Knee Score (OKS). The third component investigated retro-patellar cartilage (RPC) morphology using intraoperative examination and standardised photography. Fourthly, a cohort of patients listed for TKAs was followed prospectively, in order to assess their kneeling ability prior to and following treatment, along with identifying the factors that could affect this function, i.e. knee pain, range of motion, sensory changes and sensitivity to pain on the anterior aspect of the knee as assessed with dolorimetry. Differences were detected in the subjective interpretation of the kneeling function, as well as its importance, for the two diverse cultures involved in this study. Pain, as opposed to poor range of movement, was identified as the main reason which led to kneeling difficulties. The majority of respondents reported that it was either extremely difficult or impossible to kneel on the operated knee. The high flexed position (required for prayer in certain cultures) was the most difficult position to achieve for most of the patients. Prior to surgery, 30 patients were seen during this period, 15 (50%) out of 30 consecutive patients were unable to kneel in any position whatsoever. Of those who could kneel to some degree, the most common posture that they could achieve was the upright kneeling position. Considerable variations were found to occur in patients' understanding of the term 'kneeling'. Consequently, this has significant implications for the design and interpretation of questions in relation to kneeling for diverse cultures, which are characterised by distinct lifestyles. The current patient-based selfV administered questionnaires, such as the OKS, although useful as a simple measure of overall knee function, were found to have limitations as an effective assessment tool in the measurement of kneeling function either before or after TKA and indicate that there is a need for a culturally appropriate questionnaire to assess kneeling function. Retro-patellar cartilage lesions were very prevalent in patients undergoing TKA. However, no significant correlation existed between the total amount of retro-patellar cartilage wear and the ability to kneel. Patients were more likely to be able to kneel if the cartilage of the superior facets of the patella were disease free (P=0.02). At the six months post-surgery stage, of the 14 consecutive patients, who could kneel pre-operatively 6 were able to kneel post-operatively. Of the 13 consecutive patients who were unable to kneel pre-operatively, all were unable to kneel post-operatively. Knee pain was the main reason attributed to this difficulty. However, no link was found to occur between sensory changes and kneeling function in the patients who participated in the study, after TKA performed via an anterior midline incision.

A Síndrome da Dor Femoropatelar (SDFP) é uma das disfunções mais freqüentes do joelho, que acomete adultos jovens do sexo feminino. Embora os fatores etiológicos da SDFP ainda não estejam bem estabelecidos, autores apontam as alterações da cinemática patelar como o principal fator causal. A intervenção conservadora é freqüentemente indicada para o tratamento destes indivíduos, abrangendo exercícios em cadeia cinética aberta (CCA) e cadeia cinética fechada (CCF). O objetivo deste trabalho foi analisar a cinemática patelar durante o repouso e exercícios em indivíduos saudáveis e com SDFP. Participaram deste trabalho, 20 voluntários clinicamente saudáveis e 19 com SDFP submetidos a exames de ressonância nuclear magnética (RNM) durante o repouso, contração isométrica voluntária máxima (CIVM) em CCA e CCF com o joelho posicionado a 15º, 30º e 45º de flexão. As imagens de RNM foram avaliadas pelo programa e-film medical na obtenção dos ângulos do sulco (AS), ângulo de congruência (AC), ângulo de tilt patelar (ATP), ângulo patelar lateral (APL), deslocamento lateral patelar (DLP) e o bisect offset (BO). O coeficiente de correlação intraclasse (ICC) foi aplicado para verificar a confiabilidade intra-examinador e o modelo linear de efeitos mistos aplicado para as comparações inter e intra-grupo, sendo estabelecido nível de significância de 5%. Os resultados do ICC revelaram níveis excelentes de confiabilidade (ICC> 0,75) para todas as medidas de ambos os grupos. De acordo com os dados analisados, pode-se constatar que o grupo SDFP apresenta um maior deslocamento lateral da patela durante o repouso, CIVM em CCA e CCF com o joelho posicionado a 15º de flexão em relação ao grupo controle. Na comparação entre os posicionamentos do joelho e entre as cadeias, para ambos os grupos verificou-se um melhor equilíbrio patelar com o joelho fletido a 30º e a 45º com a CIVM em CCA e CCF. Com o joelho posicionado a 15º de flexão, a patela apresenta-se em sua posição de maior instabilidade, mesmo durante a CIVM em CCF e CCA para ambos os grupos. Desta maneira pode-se concluir que exercícios em CCA e CCF com o joelho posicionado a 30º e a 45º apresentam uma melhor estabilidade patelar em relação aos exercícios com o joelho posicionado a 15º de flexão. / Patellofemoral Pain Syndrome (PPS) is one of the most common knee dysfunctions affecting young adult women. Although PFPS etiologic factors remain uncertain, authors have reported that changes in patellar kinematics as the main cause. Conservative interventions are frequently indicated, which includes open kinetic chain (OKC) and closed kinetic chain (CKC) exercises. This study had the objective to analyze patellar kinematics on individuals with PFPS and health controls, at rest position and while performing exercises. Thirty-nine volunteers participated in this study (20 healthy individuals and 19 with PFPS) and were subjected to nuclear magnetic resonance (NMR) at the following conditions: at rest, maximal voluntary isometric contraction (MVIC) in OKC and CKC with the knee flexed at 15º, 30º, and 45º. NMR images were evaluated using e-film medical for the following angles: sulcus angle (SA), congruence angle (CA), patellar tilt angle (PTA), lateral patellar angle (LPA), lateral displacement of the patella (LDP), and bisect offset (BO). The interclass coefficient correlation (ICC) was applied to verify intra-rater reliability and the linear mixed effects model for inter- and intra-group comparisons, with level of significance at 5%. ICC results revealed excellent reliability levels (ICC> 0.75) for all measurements in both groups. The analyzed data reveal that, compared to the control group, the PFPS group presents greater lateral displacement of the patella at rest, MVIC in OKC and CKC with the knee flexed at 15º. Comparisons among knee positions and kinetic chains, in both groups, it was observed that better patellar balance was obtained with the knee flexed at 30º and 45º with MVIC in OKC and CKC. For both groups, the position with most instability of the patella is with the knee flexed at 15º, even during MVIC in CKC and OKC. Hence, it is concluded that OKC and CKC exercises with the knee flexed at 30º and 45º promote better stability of the patella with regards to exercises performed with the knee flexed at 15º

The knee joint plays an essential role in the human musculoskeletal system. It has evolved to withstand extreme loading conditions, while providing almost frictionless joint movement. However, its performance may be disrupted by disease, anatomical deformities, soft tissue imbalance or injury. Knee disorders are often puzzling, and accurate diagnosis may be challenging. Current evaluation approach is usually limited to a detailed interview with the patient, careful physical examination and radiographic imaging. The X-ray screening may reveal bone degeneration, but does not carry sufficient information of the soft tissue conditions. More advanced imaging tools such as MRI or CT are available, but expensive, time consuming and can be used only under static conditions. Moreover, due to limited resolution the radiographic techniques cannot reveal early stage arthritis. The arthroscopy is often the only reliable option, however due to its semi-invasive nature, it cannot be considered as a practical diagnostic tool. Therefore, the motivation for this work was to combine three scientific methods to provide a comprehensive, non-invasive evaluation tool bringing insight into the in vivo, dynamic conditions of the knee joint and articular cartilage degeneration. Electromyography and inverse dynamics were employed to independently determine the forces present in several muscles spanning the knee joint. Though both methods have certain limitations, the current work demonstrates how the use of these two methods concurrently enhances the biomechanical analysis of the knee joint conditions, especially the performance of the extensor mechanism. The kinetic analysis was performed for 12 TKA, 4 healthy individuals in advanced age and 4 young subjects. Several differences in the knee biomechanics were found between the three groups, identifying age-related and post-operative decrease in the extensor mechanism efficiency, explaining the increased effort of performing everyday activities experienced by the elderly and TKA subjects. The concept of using accelerometers to assess the cartilage degeneration has been proven based on a group of 23 subjects with non-symptomatic knees and 52 patients suffering from knee arthritis. Very high success (96.2%) of pattern classification obtained in this work clearly demonstrates that vibroarthrography is a promising, non-invasive and low-cost technique offering screening capabilities.