No description available.

Muscle architecture, innervation pattern and fiber type distribution of lumbar multifidus (LMT) throughout its volume was quantified. Musculotendinous (n=10) and neural components (n=3) were dissected and digitized from thirteen embalmed cadaveric specimens. The data were imported into Autodesk® Maya® 2008 to generate 3D neuromuscular models of each specimen. Architectural parameters (fiber bundle length, FBL; fiber bundle angle, FBA; tendon length) were quantified from the models using customized software. The medial branch of the posterior rami (L1-L5) was traced through LMT to determine its distribution. Using immunohistochemistry, Type I/II muscle fibers were identified in 29 muscle biopsies from one fresh frozen specimen. The total area and number of each cell type was calculated using Visiopharm® (image analysis software). Architectural and fiber type data were analyzed using ANOVA with Tukey’s post-hoc test (p ≤ 0.05). From L1-L4, LMT had three architecturally distinct regions: superficial, intermediate and deep. At L5, intermediate LMT was absent. Mean FBL decreased significantly from superficial (5.8 ± 1.6cm) to deep regions (2.9 ± 1.1cm) as did volume (superficial, 5.6 ± 2.3ml; deep, 0.7 ± 0.3ml). In contrast, mean FBA increased from superficial to deep. The medial branch of the posterior ramus (L1-L5) supplied the five bands of LMT. Each medial branch in turn divided to supply the deep, intermediate and superficial regions separately. The area occupied by Type I fibers was significantly less (p< 0.01) in the deep (56%) compared with the superficial regions (75%). Based on architecture and morphology, superficial LMT with the longest FBL and relatively small FBA is well designed for torque production and controlling the lumbar lordosis. Intermediate LMT with significantly longer FBL compared with the deep region and with its caudal to cranial line of action may help to control intersegmental stability. Furthermore, the absence of intermediate LMT at L5 and may contribute to the higher incidence of instability observed at the lumbosacral junction. Deep LMT with its short FBL, large FBA and proximity to the axis of spinal rotation may function to provide proprioceptive input to the CNS rather than a primary stabilizer of the lumbar spine.

No description available.

Muscle architecture, innervation pattern and fiber type distribution of lumbar multifidus (LMT) throughout its volume was quantified. Musculotendinous (n=10) and neural components (n=3) were dissected and digitized from thirteen embalmed cadaveric specimens. The data were imported into Autodesk® Maya® 2008 to generate 3D neuromuscular models of each specimen. Architectural parameters (fiber bundle length, FBL; fiber bundle angle, FBA; tendon length) were quantified from the models using customized software. The medial branch of the posterior rami (L1-L5) was traced through LMT to determine its distribution. Using immunohistochemistry, Type I/II muscle fibers were identified in 29 muscle biopsies from one fresh frozen specimen. The total area and number of each cell type was calculated using Visiopharm® (image analysis software). Architectural and fiber type data were analyzed using ANOVA with Tukey’s post-hoc test (p ≤ 0.05). From L1-L4, LMT had three architecturally distinct regions: superficial, intermediate and deep. At L5, intermediate LMT was absent. Mean FBL decreased significantly from superficial (5.8 ± 1.6cm) to deep regions (2.9 ± 1.1cm) as did volume (superficial, 5.6 ± 2.3ml; deep, 0.7 ± 0.3ml). In contrast, mean FBA increased from superficial to deep. The medial branch of the posterior ramus (L1-L5) supplied the five bands of LMT. Each medial branch in turn divided to supply the deep, intermediate and superficial regions separately. The area occupied by Type I fibers was significantly less (p< 0.01) in the deep (56%) compared with the superficial regions (75%). Based on architecture and morphology, superficial LMT with the longest FBL and relatively small FBA is well designed for torque production and controlling the lumbar lordosis. Intermediate LMT with significantly longer FBL compared with the deep region and with its caudal to cranial line of action may help to control intersegmental stability. Furthermore, the absence of intermediate LMT at L5 and may contribute to the higher incidence of instability observed at the lumbosacral junction. Deep LMT with its short FBL, large FBA and proximity to the axis of spinal rotation may function to provide proprioceptive input to the CNS rather than a primary stabilizer of the lumbar spine.

Injuries in the female gymnast are common and it is important to understand the biomechanical factors responsible for injury. The Back Walkover maneuver requires one of the greatest amounts of lumbar hyperextension compared to other common gymnastic maneuvers. During the Back Walkover large lateral and vertical impact forces follows on the spine. The spine and muscles around the spine have to absorb generally large forces; therefore the loads on the back and certainly on the lower back are of significant interest. Additionally, it takes a lot of strength and a vast range of motion to perform gymnastic maneuvers such as The Back Walkover. It is of interest to study mechanical loads on a female gymnast since they show higher occurrences of stress-related pathologies of the lumbar spine. Therefore the purpose of this project was to examine the loads on the spine during the gymnastic maneuver Back Walkover. Tests on a single female gymnast were made at the sports engineering lab at the University of Adelaide in Australia. Using the 3D-camera system; Optitrack Motion Capture System and Kistler Force Plate, positional data for two dimensions, X-direction (anterior-posterior) and Z-direction (vertical), and ground force were received. Data received were progressed into a graph, diagrams and biomechanical calculations where forces for the vertebrae L1 were calculated in vertical and horizontal direction. The received forces were compared to vertical and horizontal forces in L1 during standing position. Together with developed videos this assisted to model the loads of the spine (L1) during the gymnastic maneuver the “Back Walkover”. The study has led to a deeper knowledge for the community about the risks for female gymnasts and has widened the experience of the project participant, as the project aimed.

Bakalauro darbe analizuojamas kineziterapijos vertikalioje vonioje ir salėje procedūrų derinimo poveikis, pacientų funkcinės būklės, skausmo, nugaros ir pilvo raumenų statinės ištvermės kaitai, esant juosmeninės stuburo dalies skausmams. / Physiotherapy bachelor thesis analyzes the vertical bath and hall harmonization of procedures and the patient's functional status change in lumbar spine pain.

Psychosocial factors have been advanced as an explanation for the development of chronic disability in 20 to 30% of patients treated by lumbar disc surgery. Aims: The overall aim of this thesis was to study the role of psychosocial factors in patients undergoing first-time lumbar disc surgery in relation to the outcome of both surgery and subsequent physiotherapy. Methods: Sixty-nine patients with lumbar disc herniation undergoing first-time disc surgery participated in the studies; in addition, Study I included 162 knee patients for comparison. Psychosocial factors were assessed preoperatively, as was the activation of the physiological stress response system. Pain, disabil-ity and quality of life were assessed before, and 3 and 12 months after surgery. Coping and kinesiophobia were analysed before and one year after surgery. The results of two different postoperative training programmes were compared. Results: There were no differences between disc and knee patients regarding the presence of psychosocial stress factors preoperatively (Study I). Disc patients with low diurnal cortisol variability had lower physical function, perceived fewer possibilities to influence their pain and were more prone to catastrophise than patients with high diurnal cortisol variability (Study II). The results of clinic-based physiotherapy and home training did not differ regarding postoperative disability and pain 3 months after surgery. The home-based group had less pain and higher quality of life in comparison to the clinic-based group 12 months after surgery (Study III). Patients’ expectations of returning to work could best predict pain, disability, quality of life and sick leave one year after surgery (Study IV). Psychosocial factors were only weakly asso-ciated to pain, disability, quality of life and sick leave preoperatively. However, these associations were stronger in patients with residual pain one year after surgery. Conclusion: Psychosocial factors and, in particular, patients’ expectations regarding outcome are associated with the results of lumbar disc surgery. Assessing psychosocial factors preoperatively and developing an active home training programme after surgery could create options leading to better results for these patients.

This project presented a biomechanical model of the lumbosacral spine and pelvis, including novel methodologies associated with the measurement of human mechanics. This research has, for the first time, produced accurate three-dimensional geometric models of the human skeleton from living subjects using magnetic resonance imaging technology, enabling the prediction of physiological muscle action within individuals. The model was used to examine changes in the mechanics of the lumbopelvic musculoskeletal system between the standing and seated postures due to the increasing prevalence of the seated posture in the work and home environment. The outcomes of this research included a novel bone wrapping algorithm used to describe the effect of muscle-bone interactions. a novel method for creating three-dimensional in vivo spinal reconstructions using MRI, three dimensional in vivo helical axis measurements and subject specific normalised moment data.

The pelvic floor muscles (PFM) form the base of the abdominal canister, and like the other muscle groups around the canister, the abdominal muscles and the diaphragm, they contribute to and are affected by pressures within the canister. But they also have a role in organ support and continence. In urinary incontinence, clinical rehabilitation has targeted the PFM in isolation. It aims to build up strength and endurance of these muscles, but without consideration of the influence of intra-abdominal pressure, and therefore the co-ordination of muscles that generate that pressure, on PFM activity. Strengthening of the PFM has not resolved incontinence for all women, and the benefits are not sustained in the long term. Thus consideration of factors beyond the pelvic floor (PF) may lead to better outcomes for rehabilitation in both the short and long term. Thus these studies aimed to investigate the influences of abdominal muscle activity and spinal posture on the recruitment of the PFM. The studies firstly investigated the association between the abdominal and PFM during voluntary tasks. Further studies examined the effect of automatic recruitment of the PFM and the abdominal muscles with postural disturbances and changes in spinal posture, and whether there was a difference in recruitment between layers of the PFM complex during function. Electromyographic (EMG) studies, using fine wire and/or surface electrodes, were performed to record patterns of muscle activity, while, in selected studies, this was accompanied by pressures recorded within the stomach, urethra, bladder, vagina, anus and rectum, to monitor the effects of the striated muscle activity on intra-abdominal pressure and urethral function. When the PFM were voluntarily contracted in healthy women, there was a co-ordinated response in all the abdominal muscles, which varied with the position of the lumbar spine. Conversely, when the lower abdominal muscles were drawn in towards the spine there was an increase in IAP, urethral pressure and PFM EMG activity. Relaxation of the abdominal muscles and bulging of the relaxed abdominal wall decreased PFM activity and urethral pressure below their resting baselines. Thus, voluntary activation of the abdominal or PFM influences activity in the other muscle group. Other studies investigated the automatic responses of abdominal and PFM during breathing, postural perturbation, sitting and coughing. Quiet breathing was associated with modulation of PFM EMG with greater activity during expiration than inspiration, in association with variations in abdominal muscle activity. Hypercapnoea accentuated these results. Postural perturbations generated co-activation of the PF and abdominal muscles before the onset of deltoid activity with sustained activity through out repeated arm movements. Changes in spinal posture also affected PFM activity. Like the abdominal muscles, PFM were less active when sitting in a slumped position. Similar changes occurred in women with stress urinary incontinence but with lower pelvic floor muscle activity levels. Women with stress urinary incontinence also had less lordosis of the lumbar spine in upright sitting and a trend for greater superficial abdominal muscle activity than continent women. Activity of the superficial, but not deep, PFM during coughing, was affected by different sitting postures, with greater activity during coughing in slumped than in upright postures. Different breathing patterns and changes in posture also affected IAP and abdominal muscle recruitment patterns during coughing. Investigation of PFM activity during functional tasks indicates that factors beyond the PF influence its activity. The findings from these studies indicate that PFM activity is inter-related with spinal posture and abdominal muscle activity. While most of these studies were conducted in healthy women, there are a number of different types of PF problems in women, in which the mechanics of the dysfunction differ from stress urinary incontinence. PFM activity has not been investigated in all types of PF dysfunction. The findings of co-ordinated recruitment of the abdominal and PFM and the effect of spinal posture on PFM function provide some evidence that PFM rehabilitation should not be undertaken in isolation, and that there is a likely advantage from exercising with a neutral lumbar spine. There is a need for further investigation of this co-ordinated muscle recruitment in subjects with different types of dysfunction, not just stress urinary incontinence. Findings from such investigations could then point the way forward to improved rehabilitation methods for people with problems, and more suitable methods of maintaining pelvic floor health.

Background: Clinical ergonomic advice for sitting posture has been inferred from anthropometry theory and physiology studies. Qualitative observation of posture has been used to argue that postures are too flexed, too extended, too static, too mobile, require insufficient muscle activity or require too much. In other fields of healthcare, evidence is progressed from basic science to clinical trials before an intervention is prescribed, but postural advice has been prescribed from basic science without quantitative studies of postural behaviour. Spinal neuromuscular control can predict development of low back pain, it is affected by spinal pain, and can be trained, but studies examining these variables rarely measure the spinal position of their test subjects. There is a need for more detail of how spinal positions affect regional muscle activity. Study Objectives: The overall aims of this thesis were to quantify sagittal spinal postures in sitting for comparison within and between subjects and tasks, and to detail paraspinal and abdominal muscle activity associated with sitting postures. The studies quantified regional spinal curves in - Study I: typical posture behaviour during a computer task in comparison with standing, - Study II: postures that are achievable in sitting, - Study III: the regional muscle activity associated with sitting postures that have been clinically advocated as ‘ideal’, - Study IV: cohorts with and without a history of low back pain for comparison of regional muscle activity. Results and Conclusions: For clinical trials quantifying postural behaviour, the postural variation within subjects and task conditions in Study I demonstrated the importance of measurement over a prolonged period and subjects performing relevant tasks (as opposed to brief measures such as radiography that have been the standard for posture assessment). The use of surface tracking to quantify regional spinal curves and sagittal balance establish a foundation to investigate the effect of interventions on posture behaviour (eg. chair geometry, posture training, task variables and subject cohorts). Study I also showed that typical sitting posture for a computer task was more flexed at the thoracolumbar spinal region than when subjects deliberately ‘corrected’ their sitting posture, and both sitting postures were flexed at the lumbar region relative to standing. Study II showed that most subjects were unable to sit with spinal curves like those adopted in standing unless facilitation and feedback were provided, although these curves have been clinically advocated as ‘ideal’ posture. If clinical theories about ‘ideal’ sitting posture are correct, then teaching individuals the awareness of spinal position or skill to adopt these postures could be as important for workplace health and safety as other variables such as design and adjustment of office furniture. Study III showed three upright sitting postures that have been clinically advocated as ‘ideal’ were distinguished by incremental changes in activity of the lumbar multifidus muscles. In Study IV, individuals with a history of low back pain showed more incremental activity at the longissimus thoracis muscle to achieve the same sitting postures. If particular postures are shown to be ‘ideal’ in clinical trials, then training for these postures may need to focus on muscular strategies as well as spinal position. The distinct differences in regional muscle activity observed with spinal curves and subject cohorts (Studies III and IV) imply that studies of spinal neuromuscular control should measure or control spinal curves during testing. If spinal posture were controlled, the flat posture (flat surface from ~T5 to sacrum) would have the advantages of being achievable, commonly used in sitting and easily assessed. The flat posture also demonstrated the lowest muscle activity of the upright sitting postures examined, which may improve accuracy of determining muscle activity onset/offset used as an outcome measure for interventions, distinguishing cohorts or as a predictor for low back pain occurrence.