Damage to the meniscus and articular cartilage in the knee can lead to loss of function and compromise joint stability. This has led to the development of in vitro models to investigate the biomechanics and biotribological response of cartilage and menisci. In high-volume laboratory studies of cartilage tribology, it is important to measure cartilage loss after experiments. In order to understand the relationship between the structure and function of the meniscus in health and disease, it is essential to interrogate the internal structural components of the meniscus. The aims of this project were to optimise protocols for magnetic resonance imaging (MRI) of menisci and articular cartilage in the knee in order to gain an increased understanding of their structure, and to detect and quantify morphological changes. A novel porcine medial knee model was developed for creation of physiological cartilage damage using a friction simulator. The cartilage damage models were subject to in vitro MRI quantification at both 9.4 Tesla and 3.0 Tesla for the first time. The two customised MRI-based wear quantification methods were validated using Pycnometer measurements. In addition, a novel approach was developed at 9.4T MRI to non-destructively investigate intrameniscal architecture and damage. Cartilage defect models were successfully created on the femoral condyle and tibia after friction simulator tests. The follow-up MRI investigation demonstrated the capability of MRI to assess cartilage defects using laboratory and clinical systems. At both of 9.4T and 3.0T, the two quantification methods were in excellent agreement with each other and with Pycnometer measurements. An optimised 10-hour 3D scan at 9.4T could clearly demonstrate 3D intrameniscal architecture. The MRI quantification protocols showed promise for the non-destructive examination and quantification of cartilage defects in a large range of animal/human tissues after biomechanical/biotribological experiments. MRI at ultra-high-field strength also showed promise for the non-destructive examination of the intrameniscal structure in a 3D manner. The proof of concept measurements presented in this study illustrates the potential of non-destructive 3D MRI microscopy to bring a unique contribution to the field of functional cartilage/meniscus biomechanics and biotribology.

Limitations on space and power mean that limb joints for robots and prosthetics must be highly optimised for mechanical performance in areas such as stiffness, strength, friction , mechanical advantage, backlash and endurance. Biological joints me remarkably compact and long lasting and therefore it is desirable to produce bio-inspired of joints. This thesis presents a bio-inspired joint for robotics and prosthetics which is based on the human knee joint. The novel condylar joint has the same desirable features as the human knee joint including compactness is, high mechanical advantage: high stiffness and locking in the upright position. The condylar hinge joint has a mechanical advantage that is greater than that for a pin-jointed hinge by up to 35% which means that the actuator force can be reduced by up to 35% for squatting type movements. A design process has been developed for designing a condylar hinge joint for different applications. This is non-trivial because for each four-bar mechanism geometry and femur profile theme is a unique profile of tibia that has to be determined. ,ln addition, if there are constraints on the size of the tibia then it is necessary to have an iterative design process. A |Matlab code has been developed to generate the tibia profile from an animation of the four-bar motion. Parametric performance maps have been developed for two particular femur profiles. These maps show how performance varies for different four-bar mechanism geometrics. Four measures of performance are modelled which are peak mechanical advantage, RMS mechanical advantage, slicing ratio and angular range. Over 12,000 design cases have been modelled and these arc presented on a total of 44 design maps. A full size prototype has been built and tested for stiffness, friction and endurance. Additional rapid prototyping tests have been conducted in order to assess the feasibility of rapid joint construction for prosthetics.

Ankle-Foot Orthoses (AFOs) are devices applied to the foot and lower leg when ankle joint stability has been lost, commonly through, upper and lower motor neuron lesions resulting in gait abnormalities. Conventional leather and metal AFOs have been largely superseaded by plastic devices in recent years, especially made from polypropylene (PP). To date the design of AFOs is mainly based on empirical studies. A survey of the literature indicates that there is a dearth of experimental investigations in this area. Consequently, more research should be conducted on the mechanical characteristics of AFOs and their interaction with the limb in order to improve design criteria, performances and prescription of the orthoses. The objective of this project was to assess the performance of strain gauges attached to polypropylene (PP) with the perspective of using them to determine orthotic loads and stresses generated in polypropylene AFOs during patient's activity.

Studies of foot orthoses suggest that they can improve foot pain and function, although the precise mode of action of foot orthoses is poorly understood. It is proposed that they may act through the modification of abnormal stresses or motions occurring within the foot. The central aim of this thesis is to explore whether functional foot orthoses can systematically modify bone stress in the midfoot as measured on magnetic resonance imaging. Bone marrow lesion patterns quantified on magnetic resonance imaging was proposed as a surrogate measure of bone stress in the foot. A reliable method of bone segmentation and BML volume measurement was developed and applied in this thesis. In the interventional study of this thesis, the effect of functional foot orthoses on mechanical medial midfoot pain, foot impairment, patterns of bone marrow lesions and foot kinematics were investigated. Thirty seven participants with mechanical midfoot pain and medial midfoot bone marrow lesions participated in the study and were allocated to wear either functional foot orthoses (n=21) or a cushioning insole (n=16). The effect of the orthosis intervention on foot pain, impairment and volumes of magnetic resonance bone marrow lesions was compared in each group. In addition, the gait parameters and foot kinematics were assessed in a subset of 20 participants (functional foot orthoses n=10 and cushioning insole n=10). Foot pain and foot impairment outcomes improved more in the functional foot orthoses group than the control group wearing cushioning insoles. The results suggest that the volumes of bone marrow lesions in the medial foot bones were reduced systematically in the functional foot orthoses group. In comparison, those wearing the cushioning insole showed no change greater than measurement error. There was no evidence in the small subset of 7 participants, that foot kinematics were systematically altered when wearing either the cushioning insole or functional foot orthoses compared to in-shoe only analyses. The results reported in this thesis suggest that the biomechanical mechanism of functional foot orthoses in treating foot pain could be the modification of internal forces rather than their systematically influencing magnitudes of foot motion. This new data indicates that functional foot orthoses appear to have the potential to reduce foot pain and alter patterns of bone marrow lesions (a surrogate measure of bone stress) in the medial midfoot bones and further work is now required to explore this formally in larger studies.

Musculoskeletal knee conditions present a growing burden for community based rehabilitation. Outcome measures profile current health status, detect change and evaluate response to interventions. There is, however, an abundance of outcome measures but no recommendation on which to use or what data to collect, leading to widespread variation in practice. The purpose of this study was to identify those outcome measures with robust scientific evidence for adults undergoing conservative treatment of musculoskeletal knee conditions and establish, through consensus with clinicians, researchers and patients, which are acceptable and feasible for use in community based settings. An investigation of current clinical practice in NHS Scotland profiled data collection and outcome measure use in community rehabilitation. Evidenced based, validated patient vignettes were developed to establish the scope of the study. The literature reporting and testing the clinimetric properties of outcome measures was systematically reviewed and the OMERACT filters of 'truth' and 'discrimination' applied to the data for each outcome measure by an expert panel. Those measures meeting predefined quality thresholds were presented to a national Consensus Development Conference where delegates voted on their acceptability and feasibility, followed by wider public consultation. None of the 37 outcome measures identified had been fully tested or were fully supported with sufficient quality and breadth of evidence for all components of the OMERACT filter, only ten met the preset criteria for 'truth' and 'discrimination' . Five were presented to Conference and two (Lysholm and WOMAC) were subsequently recommended for use in clinical practice. Barriers to implementation included time, administration and cost. This thesis reports on a study to recommend a core set of outcome measures that could facilitate standardisation of data collection and demonstrate effectiveness of interventions for adults with musculoskeletal conditions of the knee. It captures thoughts and concerns of clinicians on the introduction of a minimum core set of outcome measures.

The use of robots to assist in knee surgery has the potential to improve the long term outcome of prosthetic implants. The robot can make accurate cuts of complex shapes that not only improve the fit of the prosthesis, but also allow for improved design. The use of pre- programmed position control of the robot can make the cuts with good results. However, there can be a sense of lack of control by the surgeon, who loses close visual and tactile feedback. In addition, the psychological needs of both patients and surgeons must be taken into account when using an autonomous robotic manipulator. The thesis describes a new approach for the use of force control whereby the surgeon can hold a cutter on the end of the robot and move it. The surgeon can supervise and control the robot directly, and execute the cutting using his/her innate sensing, experience and judgement. The strategies of implicit force control and modified damping control, with active motion constraint, can assist the surgeon in executing the pre-planned cuts accurately and efficiently. The thesis presents the analysis of the control strategies and gives results of an experimental evaluation of a three degree-of-freedom manipulator. From preliminary experiments with animal bones, the concepts of artificial motion constraint and the controller design strategy have been shown to be feasible.

Increased relative risk of non-contact anterior cruciate ligament (ACL) injury has been attributed to numerous biomechanical, anatomical and neuromuscular factors. Females are at greater relative risk of non-contact ACL injury compared with males. Dynamic knee stability is an important component required to reduce relative risk of injury, especially to the knee joint. It is difficult to directly measure knee stability; however the eccentric ability of the hamstrings to co-contract to counter the torque produced by concentric quadriceps actions during knee extension is important in stabilising the knee (determined as the functional H/Q ratio [FH/Q]). One of the proposed reasons for a greater incidence of non-contact ACL injury in females is a reduced capacity for neuromuscular functioning to stabilise the knee joint effectively. Most injuries occur in the second half of an athletic event when fatigue is commonly present, therefore identifying fatigue as a potential risk factor for ACL injury and this may allow for the development of improved prevention strategies. The three experimental studies included within this thesis (chapter 4-6) have generated novel data on sex differences in the FH/Q ratio and neuromuscular performance prior to and following a downhill running fatigue task. One hundred and ten healthy males (n=55; mean ± SD 29 ± 5 yrs) and females (n=55; mean ± SD 27 ± 6 yrs) were recruited from the university population. Isokinetic torque of the hamstrings and quadriceps was determined at 60, 120 and 240˚·s–1with the hip flexed at 0°. Range of movement of the knee joint was 90° with 0° determined as full volitional extension. Concentric (CON) torque was determined first followed by eccentric (ECC) torque, with the slowest velocity tested first. Torque was gravity corrected and filtered to only include constant velocity periods. For functional relevance FH/Q ratio was determined at 15, 30, 45º (as these are the joint angles where injury is most likely to occur) and where peak torque (PT) was achieved (to compare with the extant literature) for each movement velocity. Surface electromyography was recorded from the semitendinosus (ST), semimembranosus (SM) and biceps femoris (BF) of the dominant limb using an 8-channel DelSys EMG telemetry system. The biodex square wave synchronization pulse was configured with the EMG software via a trigger system so that EMG and torque data were completely time aligned. Raw EMG data were collected at a sampling frequency of 1024 Hz and included a common mode rejection ratio of <80 dB and an amplifier gain of 1000. Raw EMG data was band pass filtered at 20 – 450 Hz. The electromechanical delay (EMD) was determined as the time delay between the onset of muscle activation (change in activation of +15 μV) and onset of torque production (9.6 N·m) according to the procedures described by Zhou et al (1995). The aim of the first study (chapter 4) was to explore sex differences in the FH/Q ratio whilst taking into account joint angle and movement velocity. A 2 (sex) x 3 (movement velocity) x 4 (joint angle) ANOVA was performed to determine interactions and main effects. FH/Q ratio ranged from 59 to 98% in females and 66 to 109% in males across joint angles and movement velocities. No significant differences between males and females in age but males were significantly taller and had greater body mass. Irrespective of sex the FH/Q ratio increased with joint angle and movement velocity to improve knee stability during high velocity movement and near full extension. However, the FH/Q ratio is significantly lower in females compared with males and importantly this sex difference increases as movement velocity increases. Females have a lower FH/Q ratio than males close to full knee extension and during high velocity movements, both of which are predisposing factors for increased injury risk. This reduced FH/Q ratio may impair dynamic knee stability in females during fast velocity movements and may predispose them to a greater relative risk of knee injury. The aim of the second study (chapter 5) was to examine sex differences in the EMD of the hamstring muscles during eccentric muscle actions at 60, 120 and 240˚·s–1. A 2 (sex) x 3 (muscle group) x 3 (movement velocity) ANOVA was performed to determine interactions and main effects. During eccentric hamstring muscle actions there were no differences in the EMD of the 3 muscles examined. Irrespective of sex, significant main effects for angular velocity was demonstrated, indicating an increase in the delay time with increasing angular velocity. This increased delay during fast velocity movements may account for the increased risk of injury during fast movements. No significant sex differences in EMD was found irrespective of movement velocity of muscle examined, suggesting that females do not have impaired neuromuscular performance of the hamstring compared with males during eccentric hamstring muscle actions in the rested state. The aim of the third study (chapter 6) was to examine the effects of a fatigue task on sex differences of the FH/Q ratio and EMD. The procedures used in study 1 and 2 were repeated pre and post a downhill running fatigue task to explore fatigue related effects on neuromuscular functioning. Each participant performed a 40 min intermittent downhill running protocol consisting of 5 × 8 min bouts on a -10% decline, with 2 min standing rest between each bout. Irrespective of sex, joint angle or angular velocity, the FH/Q ratio was lower and EMD of hamstrings muscle was longer post-fatigue compared to pre-fatigue. Significant interactions between sex and time (pre-post) for the FH/Q ratio and EMD of hamstring muscles were found. The interactions showed a significantly lower FH/Q ratio and significantly longer EMD post fatigue in females compared to males. These data suggest that functional stability of the knee is reduced when fatigue is present and the impact of fatigue is greater in females. The findings of this thesis indicate the importance of determining the FH/Q ratio using angle specific torque as well as taking into account movement velocity, rather than simply using PT values to monitor muscle function of the knee. The findings of the present thesis support the notion that fatigue compromises the stability of the knee by reducing the FH/Q ratio and lengthening EMD. These effects are greater in females compared to males and may predispose them to greater relative risk of injury. Therefore, movement velocity, joint angle and fatigue resistance all need to be considered when designing training programmes to reduce the relative risk of injury. The focus of such training should be aimed at eccentric conditioning of the hamstring muscles to improve both muscular and neuromuscular functioning to limit the fatigue related effects, especially in females.

The primary aim of this thesis was to assess the differences in response to a 3 x 1 minute SLR tensioner treatment between 3 sub-groups of individuals with spinally referred leg pain (somatic referred pain, radicular pain and radlculopathy). · Preliminary studies of the 3 outcome measures were required prior to the main study. These were: validity ofthe method to measure nerve excursion using ultrasound imaging (VI) which was assessed in pig nerves; repeatability of sciatic nerve excursion during a side-lying modified SLR measured with UI in the posterior thigh, and repeatability of pressure pain thresholds (PPT) and vibration thresholds (VT). The 3 outcome measures were repeatable and the sciatic nerve excursion technique was valid. Sixty seven participants were placed into one of the 3 sub-groups and further assessed to identify the presence of central sensitisation (CS). Five questionnaires were completed by participants to assess disability and psychological characteristics. Sciatic nerve excursion, PPT and VT were measured prior to and after a 3 x 1 minute SLR tensioner technique. No significant differences (p>O.05) were found for any of the 3 outcome measures between the 3 groups. Slight improvements in VT were seen in the radiculopathy group after treatment, which were not significant, but indicated that even in individuals with conduction loss, no detrimental changes to nerve conduction occurred after treatment. A varied response to nerve excursion was seen. Longitudinal nerve excursion at the posterior thigh decreased after treatment in individuals with pain below the knee; this location of pain being more common in the radiculopathy and radicular groups. The decrease in nerve excursion suggests regional changes to nerve compliance after treatment, which may have occurred at the nerve root. Since it was n.ot possible to measure nerve root excursion, these findings are speculative. Only 2 participants were identified with CS, suggesting a low prevalence of the condition in individuals with spinaUy referred leg pain. This may be-Clue to individuals with CS choosing not to participate in the study, or a limitation of the method used to identify CS. Disability and psychological factors were not significantly different at baseline between the 3 sub-groups, and were not correlated with the outcome measures. A 3 x 1 minute SLR tensioner technique in individuals with spinally referred leg pain of greater than 3 months of duration is not effective in improving pain or nerve conduction. However, it is not harmful, even in individuals with loss of nerve conduction. Changes to nerve excursion after treatment may be related to individual differences in nerve compliance, and possibly restriction of the nerve root.

Background: Currently there is little published evidence exploring the experience of post discharge surgical patients who have developed infection following hip and knes joint surgery. This mixed methods syudy used both quantitative (Phase One) and qualitative (Phase Two)methodologies to explore the experience of patients with self-reported surgical site infection Methods: Phase One - Used a researcher developed postal questionnaire to identify the incidence of self-reported surgical site infection at six weeks post surgery as well as investigating the patients' experience of diagnosis, treatment and outcome following surgical site infection. Phase Two - Recruited from Phase One, twenty three patients were recruited from Phase One and invited to participate in one to one unstructured, audio taped qualitative interviews. Guided by Husserlian phenomenological approach to data collection and analysis informed by Colaizzi's method of data analysis, nine patients shared their lived experience of developing an infection post surgery. Findings: Phase One - A total of 523 patients were identified at one NHS trust and after exclusions questionnaires and stamped addressed envelopes were posted 505 patients six weeks following either total hip or total knee replacement surgery. A reponse rate 88.5% led to a final analysis of 447 questionnaires to reveal that 23 (or 5.1%)patients developed a surgical site infection, 7 in total hip replacement and 16 in total knee replacement patients. Ten infections were identified prior to discharge and 13 post discharge. Only 6 of the 23 patients were first seen by a hospital practitioner after suspecting a surgical site infection. 4 patients sought review by their general practitioner, who then referred them on to a hospital pratitioner. The remaining 13 patients utilised a combination of different management pathways. In Phase Two analysis of the nine verbatim transcriptions revealed 5 main themes of (1) Vulnerability, (2) Perception of infection, (3) Significant event, (4) Yo yoing and (5) Pendulum of care. Dicussion: Comparisons between current surveillance methods and those utilised in the study identified that current surveillance methos are likely to under represent the total number of self-reported surgical site inf

Context: Despite an association between foot structure and the incidence of lower limb injury in sport, few studies have measured the effects of neutral, pronated and supinated foot structures during dynamic activity. Furthermore, despite its widespread use as an injury prevention method, the effects of athletic taping on individuals with pronated and supinated foot structures are unclear. Objectives: To explore whether individuals with pronated and supinated foot structures have poorer lower limb neuromuscular control as measured by postural stability and muscle reaction time in comparison to those with neutral feet. Additionally, the effects of athletic taping on individuals with neutral, pronated and supinated foot structures on aspects of lower limb neuromuscular control are also examined. Subjects: All subjects used in this thesis were aged from 18 – 30 years and took part in at least two hours of exercise each week. Subjects were categorised in to groups according to navicular drop height measures; neutral 5 – 9 mm; pronated ≥ 10 mm; supinated ≤ 4 mm. Methods: Neuromuscular control was analysed in subjects with neutral, pronated and supinated feet using dynamic postural stability and muscular reaction time measures. These measures were then repeated with four athletic taping conditions (arch tape, ankle tape, proprioceptive tape and no-tape) both before and after a period of exercise. Results: Individuals with pronated and supinated foot structures were shown to have reduced postural stability in comparison to those with neutral foot structures during some dynamic tasks. Pronated and supinated foot structures also resulted in slower muscle reaction times in comparison to those with neutral feet during a tilt platform perturbation. No differences were identified between dominant and non-dominant limbs on subjects with neutral, pronated or supinated foot structures; however the high incidence of foot structure asymmetry did appear to result in differences between contralateral limbs in both postural stability and reaction time parameters. Arch and ankle taping resulted in increased neuromuscular control after application, yet these effects diminished after a period of exercise. Conclusions: The results of this thesis provide evidence to suggest that foot structure does affect lower limb neuromuscular control as measured by postural stability and muscle reaction time. In addition athletic taping has been shown to affect neuromuscular control on subjects with neutral, pronated and supinated foot structures both before and after exercise. These findings may have wide implications in sport where individuals with pronated and supinated feet may be more susceptible to injury in comparison to those with neutral feet.