Selectivity of upper limb posterior root muscle reflexes via cervicothoracic spinal cord stimulation.

Recent studies have reported that transcutaneous spinal stimulation (tSCS) may facilitate improved upper limb motor function in those with incomplete tetraplesia. However, little is known about how tSCS engages upper limb motor pools. This study aimed to explore the extent to which discrete upper limb motor pools can be selectively engaged via altering stimulus location and intensity. 14 participants with intact nervous systems completed two test visits, during which posterior root-muscle reflexes (PRMR) were evoked via a 3x3 cathode matrix applied over the cervicothoracic spine. An incremental recruitment curve at C7 vertebral level was initially performed to attain minimal threshold intensity (MTI) in each muscle. Paired pulses (1ms square monophasic with inter-pulse interval of 50ms) were subsequently delivered at a frequency of 0.25Hz at two intensities (MTI and [Formula: see text]) across all nine locations. in a random order. Evoked response to the 1st (PRMR1) and 2nd (PRMR2) stimuli were recorded from four upper limb muscles. A significant effect of spinal level was observed in all muscles for PRMR1 with greater responses recorded more caudally. Unexpectedly, contralateral cathode placement significantly increased PRMR1 in Biceps Brachii (P=0.012), Flexor Carpi Radialis (P=0.035) and Abductor Pollicis Brevis (P=0.001). Post-activation depression (PAD) was also significantly increased with contralateral cathode placement in Biceps Brachii (P=0.001), Triceps Brachii (P=0.012) and Flexor Carpi Radialis (P=0.001). These results suggest that some level of unilateral motor pool selectivity may be attained via altering stimulus intensity and location during cervicothoracic tSCS.

A practical description and student perspective of the integration of radiology into lower limb musculoskeletal anatomy.

BACKGROUND: Anatomy educators are increasing their utilisation of radiology in anatomy education in line with growing requirements for undergraduate radiology competency and clinical need. AIMS: We aimed to evaluate student perceptions of radiology and to outline the technical and academic considerations underlying the integration of radiology into musculoskeletal practical anatomy sessions. MATERIALS AND METHODS: The formal integration of radiology into anatomy practical sessions took place over a 5-week period during the lower limb musculoskeletal component of the anatomy course taught to first-year medical students. During practical sessions, students were required to rotate between aligned audio-visual radiology presentations, osteology/anatomical models, and prosection/dissection learning stations. After completing the course, students were invited to complete a survey to establish their opinions on radiology as a mode of learning and their satisfaction with radiological integration in anatomical practical sessions. RESULTS: Most students were not familiar with radiology prior to attending our university. All our students agreed or strongly agreed that learning to read radiographs in anatomy is important and most agreed that radiology is a valid assessment tool. Sixty percent stated that radiology facilitated their understanding of anatomy. The majority believed that radiology was best suited to clinically relevant anatomy and X-rays were their preferred learning tool. CONCLUSIONS: The practical approach to integrating radiology into undergraduate musculoskeletal anatomy described here did not place strain on existing academic resources. Most students agreed that radiology should be increased in anatomy education and that learning to understand radiographs in anatomy was important for clinical practice.

Examination of osteoarthritis and subchondral bone alterations within the stifle joint of an ovariectomised ovine model.

The exact relationship between osteoporosis and osteoarthritis is still a matter for debate for many. The ovariectomised ewe is frequently used as a model for osteoporosis, resulting in significant alterations in bone morphometry and turnover in both trabecular and subchondral bone after 1 year. This study examines whether ovariectomy has any impact on development of osteoarthritis within the ovine stifle joint at the same time point. In addition, we investigate whether there are any significant correlations present between articular cartilage degeneration and alterations in microstructural parameters or turnover rates in the underlying bone. Twenty-two sheep were examined in this study; 10 of the sheep underwent ovariectomy and 12 were kept as controls. Five distinctive fluorochrome dyes were administered intravenously at 12-week intervals to both groups, to label sites of bone turnover. All animals were then sacrificed 12 months postoperatively. Although most specimens showed some evidence of osteoarthritis, no measurable difference between the two study groups was detected. Osteoarthritis was associated with a thinning of the subchondral plate, specifically the subchondral cortical bone; however, whereas previous studies have suggested a link between trabecular thinning and osteoarthritis, this was not confirmed. No correlation was found between osteoarthritis and bone turnover rates of either the subchondral trabecular bone or bone plate. In conclusion, despite the fact that ovariectomy results in marked morphological and structural changes in the ovine stifle joint at 1-year postoperatively, no evidence was found to suggest that it plays a direct role in the aetiology of osteoarthritis.

Who's the doctor? Patients' perceptions of the role of the breast radiologist: a lesson for all radiologists.

OBJECTIVE: The aim of this study was to explore patients' perceptions of the role of the radiologist in their care. METHODS: The questionnaire used was designed in conjunction with a psychologist who had an interest in oncology, and piloted. The final questionnaires were distributed to patients attending the breast clinic at St James's Hospital, Dublin, Ireland, from 1 March to 1 July 2011. Patients requiring imaging (mammography and/or ultrasound) were asked to complete the same questionnaire again after imaging procedures were performed. Paired t-tests were used to assess for changes in parameters, including ranking of members of the breast care team in order of perceived importance and levels of anxiety pre and post consultation with the radiologist. RESULTS: 306 patients were recruited. 76% of patients thought that radiologists were radiographers and only 14% knew that radiologists were medical doctors. Nearly 40% of patients did not consider that radiologists had a role to play in their care. There was no statistically significant difference in the ranking of team members pre and post consultation. There was a significant improvement in patient anxiety levels after consultation with the breast radiologist, which is likely to be due to the patient learning the outcome of tests performed. CONCLUSION: There is a lack of awareness amongst patients and amongst our colleagues in paramedical disciplines regarding the roles and responsibilities of the modern radiologist. ADVANCES IN KNOWLEDGE: Radiology must act to increase public awareness so that future changes in the health service will reflect the scope and importance of the speciality.

Successful catheter directed thrombolysis of IVC and renal vein occlusive thrombus.

Thrombus formation is a recognised complication of IVC filter placement, however IVC and bilateral renal vein occlusion secondary to thrombus is much less common. We present a case of infrahepatic caval and bilateral renal vein occlusion secondary to thrombosis of a suprarenal IVC filter. With progressive clinical deterioration and failure of conservative medical management the patient underwent successful mechanical disruption and catheter directed thrombolysis.

Biomechanical comparison of the pullout properties of external skeletal fixation pins in the tibiae of intact and ovariectomised ewes.

The pin-bone interface is the least stable component of the external skeletal fixator. Concerns exist regarding the ability to obtain adequate implant purchase in poor quality bone. Consequently, reduced bone quality has been viewed as a contra-indication for the use of external skeletal fixators. The aim of this study was to investigate the holding power of two different fixator pin designs in bone from entire and ovariectomised sheep. Thirty-two aged ewes were divided into two groups. Group 1 were controls, and Group 2 were ovariectomised (OVX). The ewes were sacrificed 12 months post-ovariectomy and five pairs of tibiae were harvested from each group. The holding power of cortical and cancellous fixator pins was assessed at five standardised locations on each tibia. An increase in mean cortical thickness was noted in the OVX group. The holding power of cancellous fixator pins was superior to that of cortical pins, irrespective of whether or not ovariectomy had been performed. Cancellous pins had an increased holding power in post ovariectomy bone compared to control bone. Cortical pin performance was not affected by ovariectomy. There was a lack of correlation between the incidence of insertional fractures of the far cortex and implant holding power. The results raise questions over the effectiveness of ovariectomy in establishing osteopaenic bone suitable for assessing implant performance, hence further investigations are warranted.

Prevalence of obstructive airflow limitation in Irish collegiate athletes.

BACKGROUND: Asthma prevalence in athletes is variable, depending on the sport and training conditions. AIMS: To investigate the prevalence of obstructive airflow limitation, asthma control and lung volume differences in a control group and five groups of collegiate athletes--outdoor field, indoor court, endurance, combat sports and swimming. METHODS: Three hundred and five athletes completed a respiratory questionnaire and performed spirometry during normal training conditions, to determine FEV1, FVC and PEFR pre- and at 5, 10 and 15 minutes post-exercise. Between and within group analysis was carried out using single factor and repeated measures ANOVA. RESULTS: Previous diagnosis of asthma was reported by 24%, outdoor field sports 4.9%, indoor court sports 2.3%, endurance events 2.6%, combat sports 3%, swimming 6.9% and controls 4.3%. Mean FEV1 and FVC data, expressed as percentage of predicted, were greatest in swimming and lowest in controls. Swimming showed a significant rise in FEV1 post-exercise, indoor court and endurance sports demonstrated no change and outdoor field, combat and control groups showed a fall in FEV1 post-exercise. CONCLUSION: Warm humid training conditions appear protective against exercise-induced asthma. The greatest reductions in lung volumes occurred following high intensity exercise under cool conditions in the poorly aerobically conditioned.

A comparison of physiological responses to rowing on friction-loaded and air-braked ergometers.

The physiological responses of 10 trained rowers to a progressive incremental rowing protocol to exhaustion were investigated on Gjessing, Rowperfect fixed-mechanism and Rowperfect free-mechanism rowing ergometers. Heart rate, oxygen uptake (VO2), ventilation (VE) and blood lactate were determined at matched power values for each ergometer. The mean power and heart rate at the lactate anaerobic threshold were determined by graphical interpolation of data for each ergometer. Analysis of variance and linear regression showed differing responses at matched power and an approximate 40-50 W difference in power at the lactate anaerobic threshold when comparing the friction-loaded Gjessing with the air-braked Rowperfect fixed and Rowperfect free ergometers (P<0.01). No significant differences were noted when comparing the air-braked Rowperfect fixed and Rowperfect free ergometers. However, comparisons of VO2, VE and blood lactate at given heart rates and of heart rate at the lactate anaerobic threshold showed no significant differences between ergometers. Our results indicate similar physiological profiles for all ergometers tested when compared at equivalent heart rates, but differences when compared at matched power. A direct comparison of the data from Gjessing (friction-loaded) with Rowperfect fixed and Rowperfect free (air-braked) ergometers would therefore require a correction factor for inter-ergometer variation in displayed power data.