Separate assessment of gluteus medius and minimus: B-mode or M-mode ultrasound?

The hip abductors gluteus medius (Gmed) and minimus (Gmin) differ slightly in function and how they are affected by hip joint pathology. A separate assessment of Gmed and Gmin is feasible by ultrasound (US) imaging. B-mode and M-mode US can be used to measure muscle thickness. Two B- and two M-mode scans of Gmed and Gmin thickness were taken in relaxation on 16 asymptomatic volunteers, repeated within 4 days on 11 subjects. Three types of intra-rater reliability of muscle thickness measurements were examined: (1) within-session reliability comparing two scans from the same session, (2) between-days reliability comparing thickness from two scanning occasion within 4 days and (3) reliability of taking thickness measurements by re-measuring the same US scans after 1 week. Thickness measurements on B- and M-mode images provided ICC3,1 >0.96 for within-session reliability. ICC3,k >0.89 for between-days reliability and ICC3,1 >0.85 for re-reading the same scans were estimated. Minimal detectable changes >1.0 mm within-session, >2.4 mm between-days and >1.7 mm for re-reading scans indicated that small thickness changes are not detectable. The investigation suggests a slight advantage for fascia recognition in B-mode and the advantage of visual control of muscle relaxation in M-mode

Muscle thickness measurements to estimate gluteus mediusand minimus activity levels

The clinical assessment of gluteus medius and minimus force sharing requires non-invasive measurements of individual activity levels. Do ultrasound measurements of change of muscle thickness substitute invasive electromyography (EMG)? Isometric hip abduction in 20–80% maximal voluntary isometric contraction (MVIC) was measured using dynamometry, M-mode ultrasound for gluteus medius and minimus thickness and EMG using (1) surface electrodes on gluteus medius, n = 15, (2) fine-wire electrodes in deep gluteus medius and minimus, n = 6. Gluteus medius thickened by 5.0 (SD 2.5) mm at 80% MVIC while gluteus minimus thickness was constant in the surface EMG study and decreased by 1.6 (SD 1.6) mm at the more ventral location in the fine-wire EMG study. Thickness change of gluteus medius enabled prediction of torque (r2 0.66) and of surface EMG amplitude (r2 0.57). Surface EMG enabled higher torque prediction (r2 0.84) than thickness change. Thickness change of gluteus minimus did not enable a practically relevant estimation of torque production. Ultrasound examination revealed a differential thickening behaviour of gluteus medius and minimus which enabled estimation of isometric torque production only for gluteus medius but with lower precision than surface EMG

Qualitative data analysis in cross-cultural projects

Large-scale research projects, conducted in a cross-European context, are increasingly attractive to educational researchers and policy-makers. However, this form of comparative research across cultures brings problems concerning the standardization of data collection and analysis, particularly where ethnographic research is concerned, as it prioritizes a full range of qualitative research strategies. This paper outlines the use of a universal model and the approaches recently taken by two research teams and contrasts these with another recent nine-partner comparative European study that used ethnographic methods. We then describe the analytical procedures used in the project, which encouraged participant observation and individual researcher interpretation in order to generate grounded accounts and outline how they were culturally sensitive and meaningful to research teams who used varied analytical approaches. However, this raised difficult issues for the 'final' analysis and the production of a loosely coupled research report. Our pragmatic solution was a process of 'qualitative synthesis' whereby individual partner reports were collated by the Project Director and treated as data and a grounded theory approach was applied to generate tentative theory in respect of creative learning. The paper concludes by arguing that data generated by a loosely coupled approach to qualitative comparative research which uses a wide range of data collection methods can be effectively analysed with a qualitative synthesis

An evaluation of the effectiveness of PROMPT therapy in improving speech production accuracy in six children with cerebral palsy

This study evaluates perceptual changes in speech production accuracy in six children (3 – 11 years) with moderate-to-severe speech impairment associated with cerebral palsy before, during, and after participation in a motor-speech intervention program (Prompts for Restructuring Oral Muscular Phonetic Targets). An A1BCA2 single subject research design was implemented. Subsequent to the baseline phase (phase A1), phase B targeted each participant’s first intervention priority on the PROMPT motor-speech hierarchy. Phase C then targeted one level higher. Weekly speech probes were administered, containing trained and untrained words at the two levels of intervention, plus an additional level that served as a control goal. The speech probes were analysed for motor-speech-movement-parameters and perceptual accuracy. Analysis of the speech probe data showed all participants recorded a statistically significant change. Between phases A1 – B and B – C 6/6 and 4/6participants, respectively, recorded a statistically significant increase in performance level on the motor speech movement patterns targeted during the training of that intervention. The preliminary data presented in this study make a contribution to providing evidence that supports the use of a treatment approach aligned with dynamic systems theory to improve the motor-speech movement patterns and speech production accuracy in children with cerebral palsy

M-Mode Ultrasound Reveals Earlier Gluteus Minimus Activity in Individuals With Chronic Hip Pain During a Step-down Task

Study Design: Controlled laboratory study. Background: The hip abductor muscles are important hip joint stabilizers. Hip joint pain may alter muscle recruitment. Motion-mode (M-mode) ultrasound enables noninvasive measurements of the onset of deep and superficial muscle motion, which is associated with activation onset. Objectives: To compare (1) the onset of superficial and deep gluteus medius and gluteus minimus muscle motion relative to the instant of peak ground reaction force and (2) the level of swing-phase muscle motion during step-down between subjects with chronic hip pain and controls using M-mode ultrasound. Methods Thirty-five subjects with anterior, nontraumatic hip pain for more than 6 months (mean ± SD age, 54 ± 9 years) and 35 controls (age, 57 ± 7 years) were scanned on the lateral hip of the leading leg during frontal step-down onto a force platform using M-mode ultrasound. Computerized motion detection with the Teager-Kaiser energy operator was applied on the gluteus minimus and the deep and superficial gluteus medius to determine the time lag between muscle motion onset and instant of peak ground reaction force and the level of gluteus minimus motion during the swing phase. Time lags and motion levels were averaged per subject, and t tests were used to determine between-group differences. Results In participants with hip pain, gluteus minimus motion onset was 103 milliseconds earlier (P = .002) and superficial gluteus medius motion was 70 milliseconds earlier (P = .047) than those in healthy control participants. The level of gluteus minimus swing-phase motion was higher with pain (P = .006). Conclusion Increased gluteus minimus motion during the swing phase and earlier gluteus minimus and superficial gluteus medius motion in individuals with hip pain suggest an overall increase of muscle activity, possibly a protective behavior.These results have potential implications for understanding transport and reduction of seawater-derived sulfate in submarine hydrothermal systems. The formation of an immiscible sulfate-rich liquid phase can favor the circulation of sulfate within mid-ocean ridge basalt because the sulfate-rich liquid density is higher than that of the coexisting fluid. The reduction of sulfate could also be accelerated because sulfate is locally concentrated and strong Zn2+-SO4 2- association increases the reactivity of sulfate

M-mode ultrasound used to detect the onset of deep muscle activity

M-mode ultrasound imaging (US) reflects motion of connective tissue within muscles. As muscle contraction is accompanied by motion of muscle tissue, M-mode US may be used to measure non-invasively the onset of deep muscle activity. Isometric hip abduction was measured on nine healthy subjects in the deep region of the gluteus medius muscle and in gluteus minimus by fine-wire electromyography (EMG) and M-mode US. Following signal transformation with the Teager-Kaiser Energy Operator, EMG and M-mode US onsets of muscle activity were computer-processed. Correlation between log-transformed EMG and M-mode high-energy onsets was higher in gluteus medius (r 0.93) than in gluteus minimus (r 0.86). M-mode high-energy onsets followed EMG onset by median 33 (IQR 53) ms in gluteus medius, and by 17 (IQR 63) ms in gluteus minimus. 4% of gluteus medius and 23% of gluteus minimus M-mode onsets were detected before EMG onset. Using a higher onset threshold reduced the rate of onsets detected before EMG but also prediction accuracy. In voluntary activation, M-mode US high-energy onsets were closely related to EMG-measured onsets, but the time interval between both measures varied. The relationship of electrical and mechanical activation onsets appears to be influenced by modifying factors which may differ between muscles