Background: Jump height, utilization of the stretch-shortening cycle (SSC) and knee stability is key qualifications and important factors for athletic performance. This is usually practiced with the help of plyometric training. However, plyometric training is considered as an exercise with high-impact that adds stress on the body. Trampoline training is an activity with a growing number of adolescent’s performers, and with the ability to train the same qualities that plyometric training. However, few studies have investigated trampoline trainings effect on jump height, utilization of the SSC and the knee stability in comparison to ordinary plyometric exercises. Aim: The aim of the study was to investigate whether the jump height in a countermovement jump (CMJ) and a squat jump (SJ), the use of SSC and knee stability at landing is different in adolescents who are training using a trampoline and adolescents training using plyometric exercises. Methods: Thirty (n=30) participants, 19 handball players and 11 trampoline practitioners, aged 14-18 years, completed this cross-sectional study. This study involved three tests, a CMJ and a SJ for measuring the jump height and SSCand a double leg drop jump test for measuring the knee stability. Results: The result showed a significant difference in relative jump value between the groups, were the handball group showed a higher value in the CMJ and the SJ compared to the trampoline group. In the utilization of the SSC there were no significant difference between the groups. The result showed that there was a significant difference between the groups knee stability, were the handball group showed a greater knee degrees of varus compared to the trampoline group. Conclusion: Findings from this study suggests that adolescents might benefit from performing plyometric training to achieve a greater jump height and trampoline training to achieve a greater knee stability. Both activities had the same effect on the utilization of theSSC. More studies are needed, including a more homogenous group with larger sample sizes, to support the present results and investigate whether the results are reliable.

Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2005. / According to Wood (1998), patellofemoral pain syndrome (PFPS) refers to a syndrome that comprises of the following signs and symptoms: anterior knee pain, inflammation, imbalance, instability, or any combination thereof. Prevailing literature suggests that the presence of myofascial trigger points (MFTP’s) in quadriceps femoris (QF) muscle could result in a combination of the following signs and symptoms: - Retro- or peripatella pain, - Weakness of the quadriceps muscle (Chaitow and DeLany, 2002) - Loss of full lengthening (Travell and Simons, 1983:248-250) The aetiology of PFPS is poorly understood (Kannus et al. 1999). The current trend in literature suggests an extensor mechanism dysfunction as the most probable aetiology (Galantly et al., 1994; Juhn, 1999). There appears to be a clinical overlap between the two syndromes, in terms of an extensor mechanism dysfunction and of signs and symptoms. The aim of this investigation was to evaluate the role of active myofascial trigger points in the vastus lateralis (VL) muscle as perpetuating, causative or concomitant factors in the alteration of VL/VM Total Work (TW) in PFPS in distance runners.

Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, 2005. / To document the relationship between total work and myofascial trigger points in the vastus lateralis and vastus medialis portion of the quadriceps femoris muscle, whilst providing baseline graphs of these muscles with the use of a Cybex 700 Isokinetic Dynanometer in long distance runners both with and without patellofemoral pain syndrome. Methods: A quantitative, non-intervention clinical exploratory study. Fifty participants were divided into two groups, Group A (40 symptomatics) and Group B (10 asymptomatics). Both groups were screened for vastus lateralis and vastus medialis trigger points. Subjective data was obtained from Group A only, using the Numerical Pain Rating Scale and the Patient Specific Functional Scale. Objective data was obtained from both groups using the algometer, Myofascial Diagnostic Scale, and the Cybex 700 Isokinetic Dynanometer. For descriptive analysis frequency tabulations, box and whisker plots were used to display distributions graphically. Comparisons of categorical and quantitative variables between independent groups were run using chi square and Mann-Whitney testing consecutively. Finally Spearman’s correlation, multivariate generalized linear modelling and repeated measures ANOVA were also used. All statistical analysis was completed at the 95% (p<0.05) level of confidence. / M

Introduktion: Artros är en folksjukdom. I Sverige har var fjärde person äldre än 45 år läkardiagnostiserad artros och förekomsten ökar med ökande antal överviktiga och äldre. Genom att upptäcka och behandla tidiga stadier av artros ger vi artros patienterna en bättre förutsättning gällande funktion och symtom.                                               Syfte: Syftet var att undersöka om Functional Moves® är en verkningsfull behandlingsmetod avseende Quadriceps styrka, balans, knästabilitet, gångförmåga samt självskattad upplevelse av symtom som smärta, funktion och livskvalitet jämfört med konventionell individuell styrke- och rörlighetsträning för patienter med höft- och knäsmärta i åldern 30-65 år.                                                                       Metod: Interventionsgruppen (n=21) testades med fysiska tester samt självskattningsformulär KOOS (Knee osteoarthritis outcome score) HOOS (Hip osteoarthritis outcome score) före åtta veckors träning med Functional Moves®. Referensgruppen (n=13) testades på samma sätt och tränade i åtta veckor, med konventionell rehab träning för höft- och knäartros. Båda grupperna utvärderades inom en vecka efter avslutad träning med samma tester. Artrosskolan ingick i både interventions- och referensgruppen.                                                                                            Resultat: Interventionsgruppen hade signifikant bättre resultat på alla fysiska tester förutom enbensuppresning höger. Referensgruppen hade signifikant förbättring på enbentlängdhopp bilateralt, SOLEC vänster samt sidledshopp höger. Alla testvärden förbättrades signifikant i självskattning av frågeformulären KOOS/HOOS i både interventions- och referensgruppen.                                                               Konklusion: I denna studie har Functional Moves® visat en signifikant förbättring avseende Quadriceps styrka vänster, balans, knästabilitet, gångförmåga samt mindre skattad smärta och ansträngning vid gångtest. Functional Moves® borde erbjudas patienter i primärvården framförallt för de som har en vardag som ställer större krav på höft- och knäled. / Introduction: Osteoarthritis is a common disease. In Sweden, every fourth person older than 45 physician-diagnosed arthritis, and the incidence increases with increasing number of obese and the elderly by preventing, detecting and treating early stages of osteoarthritis, we osteoarthritis patients a better condition. Objective: The objective was to investigate whether the Functional Moves® is an effective treatment method in respect Quadriceps strength, balance, knee stability, walking capability and self-rated experience symptoms such as pain, function and quality of life compared with conventional individual strength and flexibility training for patients with hip and knee pain in age of 30-65 years. Method: The intervention group (n = 21) were tested with physical tests and self-assessment forms KOOS (Knee osteoarthritis outcome score) HOOS (Hip osteoarthritis outcome score) HOOS before eight weeks of training, with Functional moves®. The control group (n = 13) tested the same way and trained for eight weeks, with conventional rehabilitation training of hip and knee osteoarthritis. Both groups were evaluated within one week after training with the same tests. Osteoarthritis School was included in both the intervention and control group. Results: The intervention group had significantly better results on all the physical tests except one leg uprising right. The control group had significant improvement in one leg jump on both legs. SOLEC left and right side jump. All test values ​​were significantly improved in the self-evaluation of the questionnaires KOOS / HOOS in both the intervention and control group. Conclusion: In this study, Functional moves® shown a significant improvement in  Quadriceps strength left, balance, knee stability, walking capability and lower-rated pain and effort during a walking test. Functional Moves® should be offered to patients in primary care especially for those who have a living that put´s great demands on the hip and knee.

Conventional anterior cruciate ligament (ACL) reconstruction grafts have not been able to replicate the mechanical behaviour of the native ACL, reproduce normal knee mechanics and kinematics, or prevent degenerative disease progression of the knee. The aim of this thesis was to investigate a novel ACL design to more closely mimic the normal mechanical behaviour of the ACL, reconstruct the isometric ACL fibre and potentially reproduce the normal kinematics and mechanics of the knee. The designed artificial ACL reconstruction (ACLR) system could be used as a stand-alone device or in conjunction with a total knee replacement (TKR). The nominated design option for the ACLR system consisted of a connecting cord made of ultra-high molecular weight polyethylene (UHMWPE) fibres and an elastic system made of cobalt-chrome-molybdenum (CoCrMo) alloy with similar load-elongation characteristics to the native ACL. The design requirements were defined based on the mechanical properties of the native ACL, size constraints from the bony geometry and TKR components, and the location of the isometric fibres of the native ACL. The in vitro mechanical tests performed in this project on the designed cord showed a 2-3 times greater ultimate tensile load compared to the ACL in young human cadavers. The decreasing creep modulus of the UHMWPE cord under fatigue loading in simulated body conditions (3118 MPa at 6.5×10⁶ cycle) indicated nominal creep and stabilised mechanical properties by the 3000^th loading cycle. To replicate the non-linear stiffness of the ACL with ~38 N mm^-1 toe and ~100 N mm^-1 linear regions, the artificial ACLR device consisted of a femoral spring (~60 N mm^-1) in series with a tibial spring (~100 N mm^-1) and a connecting cord (~2000 N mm^-1). Two helical springs in series were used for the stand-alone ACLR, whereas a helical spring in series with a spiral spring was designed for the ACLR-TKR. As both the helical and spiral springs had a constant stiffness, stop mechanisms were added to the springs to create a non-linear stiffness and control the maximum safe deformation limit of each spring. To understand the mechanical behaviour of the reconstructed isometric fibre of the ACL, passive and loaded motions were simulated in 18 sets of segmented MRI models of healthy human knees. Constant load and elongation was observed throughout flexion during the passive movements, whereas maximal load and elongation in the reconstructed ACL was identified at 50 º of flexion during loaded motion. An ACL attachment placement sensitivity study, conducted in this project to assess the effect of surgical implantation error on the behaviour of the reconstructed ACL, revealed that misplacement of the femoral attachment would significantly influence the load-elongation of the reconstructed ACL. Finite element (FE) models of the designed ACLR devices enabled their behaviour under simulated axial loading, squatting and the Lachman test to be assessed. Both ACLR devices successfully reproduced stiffness of the native ACL with a multi-linear stiffness curve, however, elongation greater than 3.1 mm could not be achieved. It can be concluded that the designed artificial ACLR devices were able to mimic the mechanical behaviour of the ACL provided it was positioned at the isometric attachment points; potentially enabling achievement of more natural kinematics and mechanics of the reconstructed knee. However, ACL placement was shown to have a significant impact on the behaviour of the reconstructed ACL, therefore, placement error may over-constrain the joint. For this reason, a more forgiving design with a lower stiffness and a larger deformation limit would be advised.

Osteoarthritis (OA) is a debilitating joint disease that leads to significant pain, loss of mobility and quality of life. Knee malalignment results in increased joint pressure, which is a primary cause for OA progression. High Tibial Osteotomy (HTO) is a surgical procedure to correct malalignment and redistribute load in the knee joint, reduce peak pressure and delay OA progression. However, clinical outcomes have been unpredictable. Therefore, the aim of this study was to determine the relationship between malalignment and knee contact mechanics. A 3D computational model was created from magnetic resonance images of a cadaveric knee joint. A ligament tuning process was conducted to determine material properties. Finite element analyses were conducted, simulating end of weight acceptance during walking. Different wedge geometries were virtually removed to simulate malalignments from 14° valgus to 16° varus. Contact mechanics were sensitive to soft tissue material properties. In-vitro experiments were compared with computational modelling of the same specimen. Percent full-scale errors for contact force and pressure were less than 8%, demonstrating a unique subject-specific model validation. The native alignment of the cadaveric knee (1° varus) had medial and lateral compartment peak pressures of 4.28 MPa and 2.42 MPa, respectively. The medial:lateral force ratio was 70%:30%. Minimum contact stress did not occur at a Mechanical Axis Deviation (MAD) of zero millimetres nor at the Fujisawa Point, which are common targets for HTO correction. Results showed very strong correlations (r >0.94) between MAD and joint contact loading. This study is the first to demonstrate the relationship between stress (normal, shear, contact pressure) and MAD in a subject-specific model. This is a prerequisite for the development of a tool that could help surgeons make informed decisions on the degree of realignment required to minimise peak joint loading, thereby delaying OA progression.

The purpose of this study was to examine the criterion-related validity of the sit and reach test as a measure of hamstring and low back flexibility in adult males and females. Subjects were 52 males and 52 females, 20 to 45 years of age. Hamstring flexibility was measured using a goniometer. Spinal flexibility was measured using a tape measure and an inclinometer. The sit and reach test was performed according to the AAHPERD Health Related Fitness Test Manual. Data were analyzed using correlations and appropriate descriptive statistics. Conclusions of the investigation were: 1) in adult males 20 to 45, the sit and reach test is a valid measure of hamstring flexibility but has questionable validity as a measure of low back flexibility, 2) in adult females 20 to 45, the sit and reach test is a moderately valid measure of hamstring flexibility and is not a valid measure of low back flexibility.

The purpose of this study was to evaluate the amount of change in transverse tibial rotation at the knee achieved through the use of shoe modification. In addition, an attempt to evaluate the Q-angle dynamically through the stance phase to reflect changes in transverse tibial rotation was made. Ten male subjects were filmed as they ran on a treadmill at a 2.82 m/sec pace and transverse tibial rotation data was collected simultaneously from an affixed electrogoniometer at the knee joint. The subjects were tested under three conditions: 1) barefoot, 2) running shoe, and 3) shoe plus standard orthotic. The results of the study showed that an unprescribed, standard orthotic was ineffective in changing foot pronation and transverse tibial rotation at the knee. It also showed that there was no relationship between leg-heel alignment measurements of pronation and electrogoniometric measurements of transverse tibial rotation. Q-angle measurements could not be obtained from the film date due to difficulty in visualizing body landmarks.

Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2006. / The aim of this study was to assess the inter-examiner reliability of motion palpation of the patella, in both pathological (osteoarthritis) as well as functional (patellofemoral pain syndrome) conditions, in order to assess the validity of this assessment tool, which is commonly used as a method in identifying restricted patella motion. / M

Previous studies for treating Patellofemoral Pain Syndrome (PFPS) are controversial regarding the effectiveness in alleviating anterior knee pain (AKP). The muscular imbalance between the vastus medialis oblique/vastus lateralis (VMO/VL) may be the underlying mechanical issue causing PFPS. It is hypothesized that Botox can decrease the force production capability of the lateral musculature mechanically similar to surgery. Strengthening the VMO while using Botox treatment can alleviating the muscular imbalance that occurs with subjects with PFPS. A double blind study, having all participants blinded and uninformed of the injection contents, was implemented to test this hypothesis testing three female subjects. Four knees were treated. One subject received the Botox treatment and serially a placebo injection in the other limb. Two other subjects received placebo injections. EMG was executed to evaluate functional testing and the performance of the injections during extension exercises. Electromyography (EMG) data were collected from the muscle groups while the subjects performed forceful knee extension activities on an isokinetic dynamometer. In addition, kinetic jump data and self-reports of pain and activity were collected. Data were collected four times during a 12-week period. The subject who received Botox injections expressed a significant decrease in reported PFP and an increase in daily activities. Botox was safe and effective in eliminating anterior knee pain. The VMO and VL resulted in similar fatigue indices at the completion of the 12- week study. The VMO and VL both resisted fatigue during at week 12.