| dc.description.abstract | Back muscle functionality is important in maintaining stability and balance. This thesis assesses the quality of data that can be obtained from various methods used to examine back muscle function.
Magnetic resonance imaging (MRI) can be used to obtain high quality structural images of spinal muscles and from these, cross-sectional areas and volumes can be determined, which are frequently utilised as a direct indicator of muscle strength and functionality. Whether the values obtained varied with the scanning position, and specifically degree of spinal curvature, was examined to determine what impact this might have when undertaking longitudinal measurements. Overall, it was found that spinal muscle volume determinations are robust in terms of their sensitivity to participant position and spinal curvature and these factors should not have a major impact on the results in intervention studies.
Magnetic resonance spectroscopy (MRS) was used to determine the phosphocreatine (PCr) recovery rate constant in the spinal muscles following exercise, as a measure of oxidative capacity. High levels of reliability were found for the parameter when measured using a 3T scanner indicating its suitability for monitoring changes in spinal muscle functionality when undertaking longitudinal measurements.
Near infrared spectroscopy (NIRS) was used to determine the deoxyhaemoglobin recovery time constant following exercise. NIRS is a technique which is sensitive to tissue location, and it was found that in approximately 30% of the data sets acquired the signal was of too low quality to undertake fitting of the recovery data. This was most likely because of relatively high levels of subcutaneous fat being present in the back. In those cases where data fitting was possible, however, high reliability was found.
Due to Covid-19 restrictions it was not possible to undertake an intervention study using the above techniques to assess their ability to detect muscle functionality changes as originally planned. Therefore, it was decided to investigate whether there were alternative indirect measurements that could potentially be used to assess spinal muscle function. To this end, a pre-existing data set was used to examine the relationship between hand-grip strength (HGS) measurements and spinal muscle functionality, with the latter assessed via cross-sectional area measurements. Although a significant correlation was found between the two, it was determined that HGS was no better a predictor of spinal muscle size than simple anthropometry measures such as age, height, and weight. Such a finding supports the need for more direct measures of spinal muscle function if this is to be accurately monitored. | en_GB |
