Females suffer anterior cruciate ligament (ACL) injuries at a 2 to 10-fold greater rate compared to male athletes participating in similar sports. Altered movement patterns and inadequate knee stiffness are two interrelated factors that may increase ACL injury risk. Onset of these neuromuscular risk factors may coincide with the rapid adolescent growth that results in the divergence of a multitude of neuromuscular parameters between sexes. The overall purpose of this dissertation was to determine if neuromuscular ACL injury risk factors in female athletes increase following rapid growth and development compared to males. Male and female athletes were tested with three-dimensional motion analysis techniques during a drop vertical jump over two consecutive years to determine if ACL injury risk factors increased. Pubertal females showed a significant longitudinal increase in knee abduction angle compared to post-pubertal females and both male groups. The increase in knee abduction angle appeared to remain consistent, as the post pubertal female cohort had greater overall knee abduction compared to post-pubertal males. Similar results were found with a greater magnitude of knee abduction moment in post-pubertal females compared to males. Males and females increased ankle, knee and hip active stiffness from the first to second year of testing. Ankle and hip stiffness were increased significantly more in the pubertal group compared to post-pubertal. Sex and maturational group differences were found in hip and ankle joint stiffness. Post-pubertal males had significantly greater hip stiffness than the other groups (even when normalized to body mass). This indicates that post-pubertal males utilized a different neuromuscular strategy during landing. Males had a significantly greater increase from year to year in vertical jump height compared to females. Vertical jump height is often related to a measure of whole body power and indicates that males had a significant neuromuscular spurt compared to females. Early puberty appears to be a critical phase related to the divergence of increased ACL injury risk factors. Injury prevention programs that focus on neuromuscular training may be beneficial to help address the development of ACL injury risk factors that occur in female athletes during maturation.

Unicompartmental knee replacement (UKR) is the principal alternative to total knee replacement (TKR) in the treatment of end-stage knee osteoarthritis. It involves less tissue resection, resulting in lower rates of morbidity and faster recoveries compared to TKR. However, UKR has a significantly higher revision rate compared to TKR. As a result, whilst over a third of patients are eligible for UKR, only around 8% receive it. A comprehensive comparison of matched patients undergoing TKR and UKR was undertaken using a large dataset from the National Joint Registry for England and Wales (NJR). Failure rates (revision, reoperation, complications and mortality), length of stay and patient-reported outcomes (PROMs) were studied. Whilst patients undergoing TKR had lower reoperation and revision rates, they had higher rates of morbidity and mortality, longer hospital stays, and inferior PROMs compared to UKR. The main reason for revision in UKR was loosening. In view of the high revision rate in UKR, NJR data was studied to identify modifiable risk factors for failure in UKR. Important patient factors were identified including age, gender and pre-operative function. Surgeons with a higher UKR caseload had significantly lower revision rates and superior patient-reported outcomes. Increasing usage (offering UKR to a greater proportion of knee replacement patients) appears to be a viable method of increasing caseload and therefore of improving results. Surgeons with optimal usage (around 50% of patients, using appropriate implants) achieved revision/reoperation rates similar to matched patients undergoing TKR. Two clinical studies were conducted to establish whether the use of cementless fixation would improve fixation and reduce the revision rate of UKR. Cementless UKR was demonstrated to be safe and reliable, with PROMs similar or superior to those demonstrated in cemented UKR. Patients with suboptimal cementless fixation were examined and pre-disposing technical factors were identified. Finally, using NJR data, the effect of the introduction of cementless UKR on overall outcomes was examined. The number of cementless cases was small, and no significant effect on implant survival was demonstrated. However, patients undergoing cementless UKR demonstrated superior PROMs. These studies demonstrate that UKR has numerous advantages over TKR in terms of morbidity, mortality and PROMs. If surgeons perform high volumes of UKR (achievable by increasing their UKR usage), these advantages can be attained without the large difference in revision rates previously demonstrated. Cementless UKR is safe and provides superior fixation and outcomes in the hands of high-volume surgeons. Further work is needed to quantify the revision rate of cementless UKR, and to assess its results in the hands of less experienced surgeons.

The Oxford Knee Score (OKS) is a popular single summary questionnaire developed to measure the effect of knee replacement surgery from the patients' perspective. There has been a recent interest in the use of the OKS in populations of patients and in roles it has not been originally developed for. To date, no evidence has been provided about the measurement properties of the OKS when it is used outside the context or purpose for which it was originally designed. The general aim of this thesis is to investigate the measurement properties of the OKS when used in extended roles: a) within the population for which the OKS was originally intended and developed for (knee replacement) and, b) when applied on a different population, viz. patients undergoing non-operative treatment for knee osteoarthritis (OA). Four existing large-scale databases of patients undergoing knee replacement surgery and a database obtained from a prospective study on patients undergoing non-surgical management for knee OA were analyzed. The results demonstrate that: 1) it is possible to extract separate information on pain and functional disability from the OKS in a meaningful way (in the form of subscales). 2) For the first time, anchor-based Minimal Important Change (MIC) of 9 points and Minimal Important Difference (MID) of 5 points were established for joint replacement surgery. 3) The OKS demonstrated satisfactory evidence reliability, validity, responsiveness, and interpretability, when used in patients who are undergoing non-operative management for their knee OA. 4) Further evidence of validity was demonstrated by fitting the OKS to the Rasch model. 5) Lastly, it was demonstrated that thresholds can be applied on the OKS to distinguish between patients who consider their knee problem to be severe enough to warrant joint replacement surgery versus patients who do not. This supports the potential use of the OKS in decision making aids for secondary care referral. Overall the thesis provides critical evidence, not previously existing, to support the continued use, and extended use, of the OKS in orthopaedic medicine.

The goal of this thesis is summarize the current knowledge about Jumper's knee. It also includes a brief summary of the anatomy and kinesiology of the knee and then a separate chapter is devoted to the etiology, clinical picture, investigations and treatment of Jumper's knee. On these findings has been prepared and compiled research project hypotheses. This research is to determine whcther, and what affects Jumper's knee in the human musculoskeletal system. To this end, we chose a method of surface electromyography and dynamic plantography for analysis of pressure distribution and reaction forces during foot contact with the plate. Attention was focused on the comparison of side differences and timing muscle trunk and legs during dynamic activities sdccted. The results were compared with a control group that consisted of healthy individuals. Powered by TCPDF (www.tcpdf.org)

Introduction: Isokinetic testing is used in rehabilitation settings on a regular basis, yet there is a lack of consistency in rest period usage among protocols. Purpose: The purpose of this study was to establish an optimal rest period that would allow reproducibility of strength during a common isokinetic strength-test. Methods: Twentyseven healthy college-aged males underwent isokinetic strength testing to determine peak torque at 60, 180 and 300 deg/sec, respectively. Work:rest ratios of 1:3, 1:8 and 1:12 were counterbalanced between sets. A 3 X 3 repeated measures ANOVA was used to analyze the data. The p < .05 level of significance was used for all tests. Results: There was no significant difference in either knee extension or knee flexion peak torque when comparing work:rest ratios. Conclusion: These findings suggest that a 1:3 work:rest ratio is sufficient during a common isokinetic strength test.

A dor crônica de joelho secundária a osteoartrite é uma patologia comum com a progressão da idade e que vem aumentando sua prevalência a medida que se elevam a expectativa de vida e os índices de obesidade e sobrepeso. A consequência desses sintomas se reflete de maneira direta sobre a capacidade de realização de atividades diárias, a qualidade do sono e a capacidade laboral do indivíduo. O impacto psicológico, social e econômico da dor crônica de joelho representam um desafio de saúde pública, demandando tratamento eficiente e custo-efetivo. As terapias farmacológicas com frequência apresentam benefício limitado associado a diversos efeitos colaterais. Os procedimentos invasivos não cirúrgicos, como a injeção intraarticular de ácido hialurônico, representam uma alternativa em casos refratários ao tratamento clínico, sendo utilizados como terapia complementar, entretanto apresentam benefício limitado e insuficiente para o controle da dor em casos severos. Os procedimentos cirúrgicos, como a artroplastia total do joelho, habitualmente apresentam resultados satisfatórios na doença avançada, contudo são limitadas pelo seu alto custo, risco cirúrgico inerente e pequena capacidade resolutiva diante da alta prevalência. O bloqueio dos nervos geniculados é uma técnica recentemente descrita, de fácil realização e com mínima invasão necessitando ser estudada para que possa ser aplicada no manejo clínico. Neste estudo foram selecionados pacientes com osteoartrite moderada e severa, que apresentavam dor refratária ao tratamento clínico otimizado. Foram selecionados 16 pacientes e um total de 22 joelhos foram avaliados. Inicialmente todos os pacientes foram submetidos a um pré-teste que avaliava: 1) a intensidade da dor; 2) a qualidade do sono; 3) a capacidade de realização de atividades diárias. Aleatoriamente 2 grupos foram formados, o primeiro submetido ao bloqueio intra-articular e o segundo ao bloqueio dos nervos geniculados. A solução formada por: lidocaína 1% sem vasoconstrictor - 9 mL - 90 mg adicionada de Dexametasona - 1mL - 10 mg era padrão e utilizada nos dois grupos de intervenção. Após um seguimento semanal por 12 semanas consecutivas, os paciente foram reconvocados e submetidos ao outro procedimento proposto, dessa forma todos os pacientes atuaram como o seu próprio controle (desenho de estudo \"crossover\"). Nos seguimentos semanais, assim como no pré-teste, eram avaliados a intensidade da dor, a qualidade do sono e a capacidade de realização de atividades diárias. Os resultados mostraram que o bloqueio intra-articular e o bloqueio dos nervos geniculados apresentam redução importante da dor (p < 0,01), melhora na capacidade de realização de atividades diárias (p < 0,01) e melhora na qualidade do sono (p < 0,01), no entanto não houve diferença significativa no resultado entre os grupos estudados (p > 0,05). Conclui-se que o bloqueio dos nervos geniculados surge como uma alternativa segura, minimamente invasiva e de alta eficácia, apresentando resultados semelhantes ao bloqueio intra-articular. / Chronic pain of the knee secondary to osteoarthritis is a common pathology, progressive with age and which increases its prevalence as life expectancy is raised together with obesity and overweight. A consequence of these symptoms is reflected directly on the capacity of undertaking daily activities, the quality of sleep and the work capacity of each individual. The psychological, social and economic impact of chronic knee pain represents a challenge to public health, demanding efficient treatment at a worthwhile cost. Pharmaceutical therapies frequently present a limited benefit associated with various side effects. Non-surgical invasive procedures such as an injection intra-articular of hyaluronic acid, represents an alternative in refractory cases to clinical treatment, being used as a complementary therapy, however, presenting limited and insufficient benefit for the control of pain in severe cases. Surgical procedures such as complete arthroplasty of the knee, usually presents satisfactory results in patients with an advanced osteoarthritis, but are limited by their high cost, inherent surgical risk and small resolving capability facing a high prevalence. Blocking the genicular nerves is a recently described technique, easily applied by clinical management. Patients were selected in this study with moderate and severe osteoarthritis, with refractory pain in optimized clinical treatment. 16 patients were selected and a total of 22 knees were evaluated. Initially all the patients were submitted to a pre-test which evaluated: 1) the intensity of pain; 2) the quality of sleep; 3) the capacity to undertake daily activities. Two groups were formed randomly, the first submitted to intra-articular blocking and the second to blocking the genicular nerves. A solution of lidocaine 1% without a vasoconstrictor - 9 mL - 90 mg and Dexametasona - 1 mL - 10 mg was standard and used for intervention in both groups. After a weekly appraisal for 12 consecutive weeks, the patients were recalled and submitted to another proposed procedure and in this way all the patients acted as their own control (a \"crossover\" study design). In the following weeks, as also in the pretest, the intensity of pain, the quality of sleep and the capacity of undertaking daily activities were evaluated. The results showed that the intra-articular block and the blocking of the genicular nerves presented an important reduction of pain (p<0,01) but there was no significant difference in the result between the groups studied (p>0,05). It is therefore concluded that the blocking of the genicular nerves appears as a safe alternative, minimally invasive and highly efficient, presenting results similar to the intra-articular blocking.

The goals of this thesis were: (1) to develop a data acquisition system for measuring gait parameters and (2) to determine the effect of knee pads on gait and comfort. The data acquisition system consisted of a data acquisition card that was inserted in the PC card (PCMCIA) slot of a laptop computer, a knee goniometer, foot switches, and pressure sensors. Various drive circuits were designed to connect the different sensors to the data acquisition card. The gait analysis results showed that the knee pads do not have a significant effect on long range gait correlations calculated from the stride interval. Pressure measurements between the knee pads and the knee showed that a pressure in the range of 0 to 8.31 psi occurred when kneeling. The maximum pressure for the sensor located under the top strap of the knee pad occurred when getting into and out of the kneeling stance. The data acquisition system successfully met the design objectives. The stride interval was recorded and analyzed, and pressures were successfully measured and analyzed.

Introdução: O ligamento cruzado anterior (LCA) é o principal restritor à translação tibial anterior. O tratamento indicado para indivíduos atleticamente ativos é cirúrgico. Apesar de serem encontradas descrições de bons-excelentes resultados em mais de 90% dos casos, ainda há complicações relevantes, sendo a evolução para a artrose uma ocorrência frequente. Sabese que pacientes com desvio do eixo em varo, lesões condrais mediais e/ou meniscectomia medial têm maior evolução para artrose do compartimento medial. A realização da reconstrução intra-articular clássica, com tensionamento do enxerto e fixação do mesmo no túnel tibial, o qual tem ponto de entrada na metáfise medial, pode ser causa de sobrecarga medial. Objetivo: O presente estudo visa comparar duas técnicas de reconstrução intra-articular do LCA distintas entre si apenas no que tange ao ponto de entrada tibial (metáfise medial ou lateral) e o resultante grau de sobrecarga medial. Método: Estudo transversal, não randomizado, experimental em cadáveres. Três cadáveres (06 joelhos) foram submetidos à reconstrução intra-articular do ligamento cruzado anterior. Foi mensurado o grau de abertura articular medial em milímetros (mm) a 0 e 20° de flexão durante o estresse controlado em valgo (40 N) em quatro situações: LCA íntegro (grupo I), LCA seccionado (Grupo S), LCA reconstruído com o ponto de entrada do túnel tibial na posição clássica anteromedial (Grupo RC) e LCA reconstruído com o ponto de entrada do túnel tibial na posição alternativa anterolateral (Grupo RA). Resultados: A média de abertura medial a 0 e a 20 graus de flexão foram respectivamente de 3,48 e 3,55 (grupo I), 5,82 e 5,97 (grupo S), 3,22 e 3,27 (grupo RC), 5,27 e 5,28 (Grupo RA). Houve diferença significativa entre todos os grupos, com exceção da comparação Grupo I x Grupo RC, tanto a 0 como a 20 graus de flexão. Conclusão: O túnel tibial com entrada na região anterolateral da metáfise tibial lateral causa menor restrição medial do que a técnica de posicionamento clássico do túnel. / Introduction: Anterior Cruciate Ligament (ACL) is the main stabilizer of the anterior tibial translation. Surgical treatment usually is indicated for Young and active individuals. Even though good to excellent results are expected in 90% of the cases, there are several complications, and arthrosis progression still is a concern. Varus, condral and menisci injuries are well known risk of factors to gonarthrosis. Classic intra-articular ACL reconstruction with medial sided tibial tunnel positioning and tensioning can be a cause of medial compartment overload. Purpose: The present study aims to compare two similar intra-articular ACL reconstructions, differing one another only by the tibial tunnel entry, and its effect on medial compartment load. Methods: Transversal, non-randomized, experimental biomechanical study. ACL reconstruction was performed in three fresh cadavers (06 knees). Medial joint opening was measured in terms of millimeters (mm) during controlled valgus stress (40 N) both at 0 and 20 degrees of flexion. The specimens were tested in the intact state (group I) and after sectioning of ACL (group S). Also, they were tested after ACL reconstruction with medial (group MT) and lateral tunnel fixation (group LT). Results: Mean medial joint opening at 0 and 20 degrees of flexion were respectively 3,48 and 3,55 (group I), 5,82 and 5,97 (group S), 3,22 and 3,27 (group MT), 5,27 and 5,28 (group LT). Statistically significant difference occurred in comparisons between all groups, but in group I x MT, both at 0 and 20 degrees of flexion. Conclusion: The lateral based tibial tunnel for ACL reconstruction leads to lesser medial joint overload than the classic medial one.

Clinicians working on motor skill learning interventions often find that improvements observed during training are not sustained and do not transfer to very similar tasks. Research suggests that strategies such as real-time biofeedback and learner's focus of attention seem to facilitate motor skill learning. However, research on the implications of these strategies in rehabilitation is limited and has not been investigated in healthy individuals. The motor learning effects of these strategies need to be assessed as they offer the possibility of enhancing rehabilitation regimens. The purpose of this study was to investigate the generalizability of real-time biofeedback and learner's focus of attention to a treadmill gait retraining program aimed at correcting knee hyperextension insidious gait patterns in healthy young women. Assessing the acquisition, retention, and transfer of kinematic improvements was the focus of this study. 1.Knee sagittal plane kinematics could be influenced with dynamic gait training using real-time biofeedback. Gained proficiency in controlling knee hyperextension during treadmill training was evident during overground walking immediately and 1 month after training. 2.The effectiveness of real-time biofeedback in improving performance does not seem to be influenced by the focus of attention, internal or external, induced during treadmill training. Participants in both intervention groups improved in a similar way as a consequence of practice. However, there were trends in the data that pointed that the external focus of attention group had better long-term retention. It is not known if participants actively switched to an external focus of attention despite the instructions provided during training. Tests to ensure instructional compliance should be used. 3.A treadmill gait retraining program using learner's focus of attention indicated that that there were not differences in learning acquisition, short and long-term retention, and transfer to overground walking and obstacle crossing between intervention groups. It is not known if these changes persist beyond the 4-month follow-up included in this study. The results of this study will help to reduce knee hyperextension gait patterns in women. Future studies may also use the methodology used in this study to further investigate the implications of learner's focus of attention in rehabilitation. Similarly, the findings of this study could offer an additional strategy for rehabilitation regimens.

amputation, which includes reduced force generation at the knee and ankle, reduced control of the leg, and different mass properties relative to their intact leg. The physical change in the prosthetic leg leads to gait asymmetries that include spatial, temporal, or force differences. This altered gait can lead to an increase in energy consumption and pain due to compensating forces and torques. The asymmetric prosthesis demonstrated in this research aims to find a balance between the different types of asymmetries to provide a gait that is more symmetric and to make it overall easier for an amputee to walk. Previous research has shown that a passive dynamic walker (PDW) with an altered knee location can exhibit a symmetric step length. An asymmetric prosthetic simulator was developed to emulate this PDW with an altered knee location. The prosthetic simulator designed for this research had adjustable knee settings simulating different knee locations. The prosthetic simulator was tested on able-bodied participants with no gait impairments. The kinetic and kinematic data was obtained using a VICON motion capture system and force plates. This research analyzed the kinematic and kinetic data with different knee locations (high, medium, and low) and normal walking. This data was analyzed to find the asymmetries in step length, step time, and ground reaction forces between the different knee settings and normal walking. The study showed that there is symmetry in step lengths for all the cases in overground walking. The knee at the lowest setting was the closest in emulating a normal symmetric step length. The swing times for overground walking showed that the healthy leg swings at almost the same rate in every trial and the leg with the prosthetic simulator can either be symmetric, like the healthy leg or has a higher swing time. Step lengths on the treadmill also showed a similar pattern, and step length of the low knee setting were the closest to the step length of normal walking. The swing times for treadmills did not show a significant trend. Kinetic data from the treadmill study showed that there was force symmetry between the low setting and normal walking cases. In conclusion these results show that a low knee setting in an asymmetric prosthesis may bring about spatial and temporal symmetry in amputee gait. This research is important to demonstrate that asymmetries in amputee gait can be mitigated using a prosthesis with a knee location dissimilar to that of the intact leg. Tradeoffs have to be made to achieve symmetric step length, swing times, or reaction forces. A comprehensive study with more subjects has to be conducted in-order to have a larger sample size to obtain statistically significant data. There is also opportunity to expand this research to observe a wider range of kinetic and kinematic data of the asymmetric prosthesis.