Nonlinear coupling problems between the multiple bodies or between the mooring/riser and the offshore platform are incorporated in the CHARM3D-MultiBody, a fully coupled time domain analysis program for multiple bodies with moorings and risers. The nonlinear spring connection module and the three dimensional beam module are added to appropriately solve the structural connection problem. The nonlinear spring connection module includes the hydro-pneumatic tensioner module with the friction & stick/slip implementation, the tendon/mooring disconnection (breakage/unlatch) module with the tendon down-stroke check, and the contact spring with the initial gap with the friction force implemented. The nonlinear coupling may happen in many places for the offshore floating structures, such as hydro-pneumatic tensioner, tendon of TLP down stroke at the bottom joint, stick-slip phenomena at the tie down of the derrick and most of the fender-to-steel or steel-to-steel contact problem with initial gap during the installation. The mooring/tendon broken and unlatch can be a nonlinear connection problem once the transient mode is taken into account. Nonlinearity of the stiffness and friction characteristics of the tensioner combined with stick-slip behavior of riser keel joint is investigated. The relationship between tensions and strokes for hydro-pneumatic tensioner is based on the ideal gas equation where the isotropic gas constant can be varied to achieve an optimum stroke design based on tensioner stiffness. A transient effect of tendon down-stroke and disconnection on global performance of ETLP for harsh environmental condition is also investigated by incorporating the nonlinear boundary condition of the FE tendon model in CHARM3D. The program is made to be capable of modeling the tendon disconnection both at the top and the bottom connection as well as the down stroke behavior for the pinned bottom joint. The performance of the tie-down clamp of derrick is also investigated by using six degrees of freedom spring model and the three(3) dimensional FE beam model. The coupling of the TLP motion with the reaction force at the tie-down clamp is considered by using exact nonlinear dynamic equations of the motion with the reaction forces modeled with the spring or FE beam model. The method reduces too much conservatism when we design the tie-down system by the conventional method, in which all the environmental forces are combined without the phase lag effect between them. The FE beam model is also applied to the connectors between the semisubmersible and the truss for the pre-service and in-place conditions to be verified with the model test results, which shows good agreements.

Segmental post-tensioned (PT) bridges are major structures that carry significant traffic. Recent investigations of these bridges have identified voids in their ducts. and some of these exposed strands at these void locations are undergoing corrosion. The corrosion of strands may lead to the failure of tendons. As such, an effective inspection process for identifying these voids is needed. From a literature review, several non-destructive testing (NDT) methods are compared for applicability in inspecting voids in external tendons. The impact echo (IE), ultrasonic pulse velocity (UPV), and sounding inspection methods were selected and assessed for identifying voids in preliminary test setup. The sounding inspection method is further assessed for its effectiveness in identifying voids in a full-scale, external tendon system. The results indicate that the sounding inspection slightly underestimates the size of the voids. However, the inspected size and locations of voids have a close correlation with actual voids in ducts. Thus, the sounding inspection can be an effective tool for identifying voids because of its easy application in the field. Recently, the investigated failures of segmental post-tensioned (PT) bridges called attention to the rehabilitation and mitigation methods of voided ducts in PT structures. Although controversy exists on how to best protect PT tendons from corrosion, filling these voids with grout may be one option. An optimized grouting procedure for repairing these voids is needed how best to protect the strands from corrosive environments. This research investigates three grouting methods for efficiently repairing the voids in PT duct systems. These methods are (1) vacuum grouting (VG), (2) pressure grouting (PG), and (3) pressure-vacuum grouting (PVG). Each method is being evaluated for filling capability, filling performance, and economic feasibility. Also, three different pre-packaged grouts for repair are assessed in this research to propose the most suitable material for repairing voided PT ducts. The results indicate that the PG and PVG methods are more constructible and likely more economical than the VG method. However, the PVG and VG methods seem to be more effective than the PG method in filling the voids. As a result of these tests, the PVG method is recommended for filling voids in tendons. The results also show that C-1 and C-2 grouts have better filling capability than C-3 grout. Although experimental tests using prototype specimens of external PT tendons are performed to propose an effective repair grouting method and material, the experimental conditions cannot cover all voids types, duct types, and other effects of repair grouting methods in the field. Thus, the grout flow in voided ducts is predicted using a commercial Computational Fluid Dynamics (CFD) program. The simulation of the flow is challenging due to the complicated geometry of voided ducts, but the simplified model in this research shows close correlations with experimental results. Thus, various parameters of repair methods and materials are assessed in this research, and the PVG method with grouts having low viscosity exhibited the best performance. If it is determined that filling voids with grout is appropriate and prevents future corrosion, it is recommended that voids in the field be filled using the PVG method with grouts exhibiting low viscosities.

Moment arms are important in many contexts. Various methods have been used to estimate moment arms. It has been shown that a moment arm changes as a function of joint angle and contraction state. However, besides the influence of these anatomical factors, results from recent studies suggest that the estimation of moment arm is also dependent on the methods employed. The overall goal of this thesis was to explore the interaction between the methodological and anatomical influences on moment arm and their effect on estimates of muscle-tendon forces during biomechanical modelling. The first experiment was a direct comparison between two different moment arm methods that have been previously used for the estimation of Achilles tendon moment arm. The results of this experiment revealed a significant difference in Achilles tendon moment arm length dependent on the moment arm method employed. However, besides the differences found, results from both methods were well correlated. Based on these results, methodological differences between these two methods were compared across different joint angles and contraction states in study two. Results of experiment two revealed that Achilles tendon moment arms obtained using both methods change in a similar way as a function of joint angle and contraction state. In the third experiment, results from the first two experiments were used to determine how methodological and anatomical influences on Achilles tendon moment arm would change muscle-tendon forces during the task of submaximal cycling. Results of the third experiment showed the importance of taking the method, ankle angle and contraction state dependence of Achilles tendon moment arm into account when using biomechanical modelling techniques. Together, these findings emphasis the importance of carefully considering methodological and anatomical modifiers when estimating Achilles tendon moment arm.

No description available.

Introduction: Elderly females are predominantly left impaired by the degenerative impact which osteoarthritis has on the 1st CMC joint. Research supports the successful implementation of early stage conservative management. Aim: To determine the viability of performing a full scale study to investigate the influence of an abductor pollicis longus strengthening program on the symptoms experienced by elderly females presenting with early stage osteoarthritis of the 1st CMC joint. Objectives: Validating data gathering instruments; evaluating methods and procedures used for recruiting, randomization; retaining, assessing and facilitating compliance of participants. Evaluation of the data capturing process. Required resources and sample size for a scientifically valid full scale study was estimated. Method: The pilot study made use of the quantitative research design proposed for a full scale study. Tools such as cost sheets and compliance logbooks were implemented along with qualitative components such as feedback questionnaires and field notes. Three retirement homes participated; 25 residents qualified to participate of which 15 were allocated to the experimental group and 10 to the control group. The experimental group participated in an 8 week exercise program; while the control group received an assistive device. Both the experimental and control groups were assessed at baseline; four weeks and after eight weeks. The assessment battery included the Kapandji index for thumb opposition, voluntary isometric total grip, 2-point pincer, 3-point pincer and key grasp strength, Visual Analogue Scale for pain and the Michigan Hand Outcome Questionnaire (MHQ). Data analysis: Data was captured by the researcher; the MHQ and feedback questionaires were independantly completed by the partiticpants. Data cleansing was conducted manually where corectness was verified by a third uninvolved party. Quantitative data was summarized and tested with the vi Generalized Estimating Equations (GEE) to detect possible changes over time. Inferential analysis and comparisons of results for the experimental and control groups could not be made. The researcher detected themes and subthemes within the qualitative data. Results/Discussion: Recruitment techniques’ response rate did not exceed 27%; qualitative data sets identified influencing factors An inclusion age of 60 years and older were suggested and to extend the research to various ethic groups. A large enough sample group for randomization was not obtained. Recommended adjustments to the assessment battery: using an adjusted MHQ as the full MHQ includes unapplicable questions; using a Numerical Rating Scale (NRS) for pain potentially being more user friendly for an elderly population; and an additional abduction active range of motion goniometer assessment for the thumb is recommended as the Kapandji scale for opposition provided limited information concerning the range of motion of the 1st CMC joint. The calculated cost per participant was R1921.60 for the control group and R3179.79 for the experimental group. Human resources were calculated at 64.2% of the entire budget. Compliance was affected by poor memory and health. Population attrition rates were calculated at an average of 48%. The feedback questionaires indentified personal gain and the feeling of contributing to a research initiative as the predominant themes for retaining the target population. Conclusion:The conducted pilot study can be used to define the parameters necessary to conduct then mentioned full scale research study, as well as assist with research designs envolving a similar target population. One more pilot study is recommended prior to a full scale study addressing topics such as including diverse races; recommended additional assessment tools and intervnetion components. / Thesis (M.O.T.)-University of KwaZulu-Natal, Durban, 2014.

The purpose of this study was to determine the functional changes due to the Graston Therapeutic Technique (GTT) in an animal model. This study attempted to verify the biomechanical changes associated with the Graston Therapeutic Technique (GTT) in order to possibly apply it to humans as a major physical therapy modality. Eighteen adult, male Sprague-Dawley rats were assigned randomly to three groups. The groups were classified as follows: (a) no injured plus GTT treatment, (b) injured minus GTT treatment, (c) injured plus GTT treatment. The GTT therapy began after one week following injury to allow for optimum inflammation and scar formation. The animals receiving GTT had six treatments over the course of two weeks. Running tests were performed on a treadmill at a velocity of 22 cm/s prior to induction of injury, one week following injury, two weeks following injury, and three weeksfollowing injury in the experimental groups. Variables analyzed were knee and ankle range of motion (ROM), stride length (SL), and stride frequency (SF). Significance of effect between experimental groups were determined by repeated measures one-way ANOVA, Scheffe's post hoc test, and Newman-Keuls post hoc test. The stride length and stride frequency results of the present study appeared to indicate that the Graston Therapeutic Technique (GTT) had an effect on changes in the stride length and stride frequency after injury. Statistical analysis between observations for the GTT plus groups indicated a significant difference in the swing phase of knee ROM. The results of this study also indicated that the Graston Therapeutic Technique may have had an influence on knee joint range of motion. / School of Physical Education

The current study evaluated whether robotic guidance can influence movement planning and/or the use of online proprioceptive feedback. Participants were divided into three groups wherein they practiced an aiming task unassisted or via a robotic device that led them through a trajectory with an asymmetric or symmetric velocity profile. Baseline performance was measured prior to training and a post-test included control and tendon vibration trials. Temporal, spatial, and kinematic variables were used to assess planning and online control mechanisms. Results indicated that tendon vibration altered the way individuals planned their movements and used online sensory feedback. Robotic-guided groups appeared to use online feedback to a lesser extent than the unassisted group during tendon vibration trials, based on kinematic data. Individuals may become less inclined to use erroneous proprioceptive feedback following robotic guidance, supporting the potential benefit of robotics in neuro-motor rehabilitation for those with proprioceptive deficits.

The interplay of structures in the finger that facilitate movement is complex and not yet fully understood. Subtle finger injuries are often missed during the initial assessment in the Emergency Department, because clinical examination of the acutely injured hand can be difficult. The consequences of unrecognized finger injuries can be devastating for the patient. Ultrasound imaging of tendons is a useful investigative tool although little has been published regarding the reliability of finger tendon measurements. The overall objective of this project was to establish if bedside ultrasound imaging of tendons was possible and useful in the setting of acute injury. The project was divided into two studies.In the first study, 65 apparently normal volunteers were scanned to allow the principal investigator to practise and refine the ultrasound technique. The dimensions of the Extensor Digitorum Longus and two flexor tendons combined (Flexor Digitorum Profundus and Flexor Digitorum Superficialis) were measured in both transverse and longitudinal sections. Fifteen of the volunteers had their left middle fingers scanned twice within 48 hours to establish the test to retest reliability of tendon measurement. The established scanning technique was simple to perform and the scans, including both static and real time images, were completed within five minutes. All volunteers were able to tolerate a full scan. Measurement of tendon width showed fair to good reliability (Intra class correlation [ICC] of flexor tendons = 0.66, ICC of extensor tendon = 0.54). However measurement of the depth of all the tendons was unreliable test to retest (ICC < 0.37).In the second study, 30 patients who presented to the Emergency Department at Lismore Base Hospital with hand injuries were scanned for evidence of tendon injury and tendon gliding restriction. The patient’s ability to tolerate ultrasound examination was investigated. The scan findings were compared with the clinical findings and then to the operation report or to the patient’s self reported outcome, one month after injury.Patients were willing to undergo ultrasound examination regardless of the extent of their injury. There was a significant difference (p = 0.04) in scan tolerance related to the site of injury with 50% of those with extensor surface injuries having completed scans in comparison to 36% with flexor surface injuries and 9.1% of finger tip injuries. Injury mechanism was not related to scan tolerance.Excluding a partial tendon laceration was technically difficult due to the presence of anisotropy artefact. However, all complete tendon lacerations were successfully identified prior to surgery. The gliding of the tendons was easy to visualize and abnormal gliding was found to be a marker of tendon injury.The overall results show that ultrasound imaging of finger tendons at the bedside in the Emergency Department is a feasible examination to perform. The addition of ultrasound examination, however, did not identify any cases of tendon injury not already suspected on routine clinical examination.Therefore, this pilot study suggests that routine use of ultrasound examination to detect finger tendon injury in the Emergency Department setting will not prove to be a useful investigation. There may be a role for ultrasound as a screening tool as the gliding of normal tendons differed noticeably from the gliding of injured tendons. The presence of normal tendon gliding may be helpful in identifying those patients that are safe to be discharged from the Emergency Department without further evaluation.

The interplay of structures in the finger that facilitate movement is complex and not yet fully understood. Subtle finger injuries are often missed during the initial assessment in the Emergency Department, because clinical examination of the acutely injured hand can be difficult. The consequences of unrecognized finger injuries can be devastating for the patient. Ultrasound imaging of tendons is a useful investigative tool although little has been published regarding the reliability of finger tendon measurements. The overall objective of this project was to establish if bedside ultrasound imaging of tendons was possible and useful in the setting of acute injury. The project was divided into two studies.In the first study, 65 apparently normal volunteers were scanned to allow the principal investigator to practise and refine the ultrasound technique. The dimensions of the Extensor Digitorum Longus and two flexor tendons combined (Flexor Digitorum Profundus and Flexor Digitorum Superficialis) were measured in both transverse and longitudinal sections. Fifteen of the volunteers had their left middle fingers scanned twice within 48 hours to establish the test to retest reliability of tendon measurement. The established scanning technique was simple to perform and the scans, including both static and real time images, were completed within five minutes. All volunteers were able to tolerate a full scan. Measurement of tendon width showed fair to good reliability (Intra class correlation [ICC] of flexor tendons = 0.66, ICC of extensor tendon = 0.54). However measurement of the depth of all the tendons was unreliable test to retest (ICC < 0.37).In the second study, 30 patients who presented to the Emergency Department at Lismore Base Hospital with hand injuries were scanned for evidence of tendon injury and tendon gliding restriction. The patient’s ability to tolerate ultrasound examination was investigated. The scan findings were compared with the clinical findings and then to the operation report or to the patient’s self reported outcome, one month after injury.Patients were willing to undergo ultrasound examination regardless of the extent of their injury. There was a significant difference (p = 0.04) in scan tolerance related to the site of injury with 50% of those with extensor surface injuries having completed scans in comparison to 36% with flexor surface injuries and 9.1% of finger tip injuries. Injury mechanism was not related to scan tolerance.Excluding a partial tendon laceration was technically difficult due to the presence of anisotropy artefact. However, all complete tendon lacerations were successfully identified prior to surgery. The gliding of the tendons was easy to visualize and abnormal gliding was found to be a marker of tendon injury.The overall results show that ultrasound imaging of finger tendons at the bedside in the Emergency Department is a feasible examination to perform. The addition of ultrasound examination, however, did not identify any cases of tendon injury not already suspected on routine clinical examination.Therefore, this pilot study suggests that routine use of ultrasound examination to detect finger tendon injury in the Emergency Department setting will not prove to be a useful investigation. There may be a role for ultrasound as a screening tool as the gliding of normal tendons differed noticeably from the gliding of injured tendons. The presence of normal tendon gliding may be helpful in identifying those patients that are safe to be discharged from the Emergency Department without further evaluation.

Diss. (sammanfattning) Umeå : Univ., 2006. / Härtill 4 uppsatser.