Cortical Inhibition of Face and Jaw Muscle Activity and Discomfort Induced by Repetitive and Paired-Pulse TMS During an Overt Object Naming Task.

Modulatory effects of transcranial magnetic stimulation (TMS) strongly depend on the stimulation parameters. Here, we compared the immediate, task-locked inhibitory effects on speech-related muscles and the tolerability of different TMS protocols during a language production task. Repetitive TMS (rTMS) and paired-pulse TMS (PP) were applied in 13 healthy subjects over the primary motor cortex (M1) during a finger-tapping/tongue-twisting tasks. The lowest subject-specific TMS intensity leading to movement disruptions was used for TMS over left-sided speech-related areas during picture naming. Here, time-locked PP and rTMS (10/30/50 Hz; randomized sequence) were applied. Cortical silent periods (cSPs) were analyzed from electromyography obtained from various face muscles. 30 Hz- and 50 Hz-rTMS reliably evoked tongue movement disruption (ICC = 0.65) at lower rTMS intensities compared to 10 Hz-rTMS or PP. CSPs were elicited from the left hemisphere by all TMS protocols, most reliably by PP (p < 0.001). Also, cSPs with longest durations were induced by PP. Exploratory analyses of PP suggest that the trials with strongest motor inhibitory effects (presence of cSP) were associated with more articulatory naming errors, hence hinting at the utility of TMS-elicited, facial cSP for mapping of language production areas. Higher-frequency rTMS and PP evoked stronger inhibitory effects as compared to 10 Hz-rTMS during a language task, thus enabling a probably more efficient and tolerable routine for language mapping. The spatial distribution of cranial muscle cSPs implies that TMS might affect not only M1, but also distant parts of the language network.

Modulation of motor cortical excitability with auditory stimulation.

Loud sounds have been demonstrated to increase motor cortex excitability when transcranial magnetic stimulation (TMS) is synchronized with auditory evoked N100 potential measured from electroencephalography (EEG). The N100 potential is generated by an afferent response to sound onset and feature analysis, and upon novel sound it is also related to the arousal reaction. The arousal reaction is known to originate from the ascending reticular activating system of the brain stem and to modulate neuronal activity throughout the central nervous system. In this study we investigated the difference in motor evoked potentials (MEPs) when deviant and novelty stimuli were randomly interspersed in a train of standard tones. Twelve healthy subjects participated in this study. Three types of sound stimuli were used: 1) standard stimuli (800 Hz), 2) deviant stimuli (560 Hz), and 3) novelty stimuli (12 different sounds). In each stimulus sequence 600 stimuli were given. Of these, 90 were deviant stimuli randomly placed between the standard stimuli. Each of 12 novel sounds was presented once in pseudorandomized order. TMS was randomly mixed with the sound stimuli so that it was either synchronized with the individual N100 or trailed the sound onset by 200 ms. All sounds elicited an increase in motor cortex excitability. The type of sound had no significant effect. We also demonstrated that TMS timed at 200-ms intervals caused a significant increment of MEPs. This contradicted our hypothesis that MEP amplitudes to TMS synchronized with N100 would be greater than those to TMS at 200 ms after a sound and remains unexplained. NEW & NOTEWORTHY We demonstrated modulation of motor cortical excitability with parallel auditory stimulus by combining navigated transcranial magnetic stimulation (TMS) with auditory stimuli. TMS was synchronized with auditory evoked potentials considered to be generated by the unconscious attention call process in the auditory system.

Efficient Mapping of the Motor Cortex with Navigated Biphasic Paired-Pulse Transcranial Magnetic Stimulation.

Navigated transcranial magnetic stimulation (nTMS) can be applied to locate cortical muscle representations. Usually, single TMS pulses are targeted to the motor cortex with the help of neuronavigation and by measuring motor evoked potential (MEP) amplitudes from the peripheral muscles. The efficacy of single-pulse TMS to induce MEPs has been shown to increase by applying facilitatory paired-pulse TMS (ppTMS). Therefore, the aim was to study whether the facilitatory ppTMS could enable more efficient motor mapping. Biphasic single-pulse TMS and ppTMS with inter-stimulus intervals (ISIs) of 1.4 and 2.8 ms were applied to measure resting motor thresholds (rMTs) as a percentage of the maximal stimulator output and to determine the cortical representation areas of the right first dorsal interosseous muscle in healthy volunteers. The areas, shapes, hotspots, and center of gravities (CoGs) of the representations were calculated. Biphasic ppTMS with ISI of 1.4 ms resulted in lower rMTs than those obtained with the other protocols (p = 0.001). With ISI of 2.8 ms, rMT was lower than with single-pulse TMS (p = 0.032). The ppTMS mapping was thus performed with lower intensity than when using single-pulse TMS. The areas, shapes, hotspots, and CoGs of the muscle representations were in agreement. Hence, biphasic ppTMS has potential in the mapping of cortical hand representations in healthy individuals as an alternative for single-pulses, but with lower stimulation intensity by utilizing cortical facilitatory mechanism. This could improve application of nTMS in subjects with low motor tract excitability.

Protocol for motor and language mapping by navigated TMS in patients and healthy volunteers; workshop report.

INTRODUCTION: Navigated transcranial magnetic stimulation (nTMS) is increasingly used for preoperative mapping of motor function, and clinical evidence for its benefit for brain tumor patients is accumulating. In respect to language mapping with repetitive nTMS, literature reports have yielded variable results, and it is currently not routinely performed for presurgical language localization. The aim of this project is to define a common protocol for nTMS motor and language mapping to standardize its neurosurgical application and increase its clinical value. METHODS: The nTMS workshop group, consisting of highly experienced nTMS users with experience of more than 1500 preoperative nTMS examinations, met in Helsinki in January 2016 for thorough discussions of current evidence and personal experiences with the goal to recommend a standardized protocol for neurosurgical applications. RESULTS: nTMS motor mapping is a reliable and clinically validated tool to identify functional areas belonging to both normal and lesioned primary motor cortex. In contrast, this is less clear for language-eloquent cortical areas identified by nTMS. The user group agreed on a core protocol, which enables comparison of results between centers and has an excellent safety profile. Recommendations for nTMS motor and language mapping protocols and their optimal clinical integration are presented here. CONCLUSION: At present, the expert panel recommends nTMS motor mapping in routine neurosurgical practice, as it has a sufficient level of evidence supporting its reliability. The panel recommends that nTMS language mapping be used in the framework of clinical studies to continue refinement of its protocol and increase reliability.

Midbrain-to-pons ratio in autopsy-confirmed progressive supranuclear palsy: replication in an independent cohort.

Recent neuropathologically confirmed clinical data suggest that the midbrain-to-pons ratio, as calculated from conventional brain MRI, has high specificity and sensitivity for the diagnosis of progressive supranuclear palsy (PSP). Here, we aimed to replicate these findings in an independent autopsy-confirmed cohort of 6 PSP patients and 23 non-PSP patients. Patients with confirmed PSP had clearly lower midbrain-to-pons ratios compared to non-PSP patients (p < 0.0001). All non-PSP patients had midbrain-to-pons ratios higher than 0.50, whereas all but one PSP patient had a ratio lower than 0.50. The positive predictive value (PPV) of the ratio (<0.50) was 100% and the negative predictive value (NPV) was 95.8 %. The results of this second autopsy-confirmed sample confirm that midbrain-to-brain ratios constitute reliable and clinically useful estimates of diagnostic midbrain atrophy in relation to PSP pathology.

[Rare causes of progressive paraparesis]. / Etenevän parapareesin harvinaisia syitä.

Progressive paraparesis is a neurosurgical and neurological emergency. The patient's neurological outcome relies on the course of the diagnostics and treatment. Physicians having experience in emergency medicine are familiar with the typical etiologies of paraparesis. Uncommon causes of paraparesis may, however, elicit diagnostic challenges. Intraspinal bleeding causes a rapid progression of the symptoms. Intraspinal epidural hematoma is a rare complication of spinal anaesthesia and may be diffcult to diagnose if the blood is located in the subarachnoidal space. Spinal arteriovenous malformations and arachnoideal cysts causing medullary compression, and myelitis may present with slowly proceeding paraparesis. The diagnostics of the conditions described above is often difficult and typically requires facilities that are available only in larger centers.

Protocol for mapping of the supplementary motor area using repetitive navigated transcranial magnetic stimulation.

Background: Damage to the supplementary motor area (SMA) can lead to impairments of motor and language function. A detailed preoperative mapping of functional boarders of the SMA could therefore aid preoperative diagnostics in these patients. Objective: The aim of this study was the development of a repetitive nTMS protocol for non-invasive functional mapping of the SMA while assuring effects are caused by SMA rather than M1 activation. Methods: The SMA in the dominant hemisphere of 12 healthy subjects (28.2 ± 7.7 years, 6 females) was mapped using repetitive nTMS at 20 Hz (120% RMT), while subjects performed a finger tapping task. Reductions in finger taps were classified in three error categories (≤15% = no errors, 15-30% = mild, >30% significant). The location and category of induced errors was marked in each subject's individual MRI. Effects of SMA stimulation were then directly compared to effects of M1 stimulation in four different tasks (finger tapping, writing, line tracing, targeting circles). Results: Mapping of the SMA was possible for all subjects, yet effect sizes varied. Stimulation of the SMA led to a significant reduction of finger taps compared to baseline (BL: 45taps, SMA: 35.5taps; p < 0.01). Line tracing, writing and targeting of circles was less accurate during SMA compared to M1 stimulation. Conclusion: Mapping of the SMA using repetitive nTMS is feasible. While errors induced in the SMA are not entirely independent of M1, disruption of the SMA induces functionally distinct errors. These error maps can aid preoperative diagnostics in patients with SMA related lesions.

Corticospinal output and cortical excitation-inhibition balance in distal hand muscle representations in nonprimary motor area.

Transcranial magnetic stimulation (TMS) of the superior frontal gyrus in the non-primary motor area (NPMA) can evoke motor-evoked potentials (MEPs) at 20 ms latency range in contralateral distal hand muscles similar to stimulation of M1 and indicating monosynaptic corticospinal tracts. We compared the intracortical inhibitory and excitatory balance in primary motor cortex (M1) and in NPMA by navigated single- and paired-pulse TMS (ppTMS). We also evaluated the spatial stability of muscle representations in M1 and NPMA by remapping 11 healthy subjects one year after the initial mapping. Resting motor threshold (rMT) was higher in NPMA than in M1 as were the MEP amplitudes evoked by 120% rMT stimulation intensity of the local MT. Short-interval intracortical inhibition (SICI) was significantly weaker in NPMA than in M1 at ISI of 2 ms and conditioning stimulus (CS) 80% rMT. Our findings suggest that the cortical hand representations in NPMA 1) are connected to lower motoneurons monosynaptically, 2) are less strictly organized, i.e. motoneuron population representing a discrete hand muscle is sparser and less dense than in M1 and 3) have the capacity to generate powerful, rapid muscle contraction if sufficient number of motoneurones are activated. In NPMA, local intracortical inhibitory and excitatory activity is mainly similar to that in M1. The lower SICI in NPMA at an ISI of 2 ms may reflect less strict topographic organization and readiness to reorganization of neural circuits during motor learning or after motor deficits.

Brain Response Induced with Paired Associative Stimulation Is Related to Repetition Suppression of Motor Evoked Potential.

Repetition suppression (RS), i.e., the reduction of neuronal activity upon repetition of an external stimulus, can be demonstrated in the motor system using transcranial magnetic stimulation (TMS). We evaluated the RS in relation to the neuroplastic changes induced by paired associative stimulation (PAS). An RS paradigm, consisting of 20 trains of four identical suprathreshold TMS pulses 1 s apart, was assessed for motor-evoked potentials (MEPs) in 16 healthy subjects, before and following (at 0, 10, and 20 min) a common PAS protocol. For analysis, we divided RS into two components: (1) the ratio of the second MEP amplitude to the first one in RS trains, i.e., the "dynamic" component, and (2) the mean of the second to fourth MEP amplitudes, i.e., the "stable" component. Following PAS, five subjects showed change in the dynamic RS component. However, nearly all the individuals (n = 14) exhibited change in the stable component (p < 0.05). The stable component was similar between subjects showing increased MEPs and those showing decreased MEPs at this level (p = 0.254). The results suggest the tendency of the brain towards a stable state, probably free from the ongoing dynamics, following PAS.

Thalamic Atrophy Predicts 5-Year Disability Progression in Multiple Sclerosis.

Purpose: Thalamus is among the first brain regions to become atrophic in multiple sclerosis (MS). We studied whether thalamic atrophy predicts disability progression at 5 years in a cohort of Finnish MS patients. Methods: Global and regional brain volumes were measured from 24 newly diagnosed relapsing MS (RMS) patients 6 months after initiation of therapy and from 36 secondary progressive MS (SPMS) patients. The patients were divided into groups based on baseline whole brain parenchymal (BP) and thalamic atrophy. Standard scores (z scores) were computed by comparing individual brain volumes with healthy controls. A z score cutoff of -1.96 was applied to separate atrophic from normal brain volumes. The Expanded Disability Status Scale (EDSS), brain magnetic resonance imaging (MRI) findings, and relapses were assessed at baseline and at 2 years and EDSS progression at 5 years. Results: Baseline thalamus volume predicted disability in 5 years in a logistic regression model (p = 0.031). At 5 years, EDSS was same or better in 12 of 18 patients with no brain atrophy at baseline but only in 5 of 18 patients with isolated thalamic atrophy [odds ratio (OR) (95% CI) = 5.2 (1.25, 21.57)]. The patients with isolated thalamic atrophy had more escalations of disease-modifying therapies during follow-up. Conclusion: Patients with thalamic atrophy at baseline were at a higher risk for 5-year EDSS increase than patients with no identified brain atrophy. Brain volume measurement at a single time point could help predict disability progression in MS and complement clinical and routine MRI evaluation in therapeutic decision-making.

Interaction between repetition suppression in motor activation and long-interval intracortical inhibition.

Repetition suppression (RS) is the adaptation of the neural activity in response to a repeated external stimulus. It has been proposed that RS occurs at the thalamo-cortical level, hence activating a feedback loop to the cortex in order to counteract with the repeated motor cortical activation. In this study, to elucidate the common modulators between the RS and the inhibitory/facilitatory cortical networks, two TMS paradigms were applied, i.e. the characteristic long-interval intracortical inhibition (LICI) and the I1-wave timed short-interval intracortical facilitation (SICF). Since LICI is a local intracortical inhibitory phenomenon affecting cortical excitation over a long interval like the RS, the interaction between RS and LICI was tested. As the I1-wave timed SICF is likely not affected by inhibitory modulation, the appearance of the RS with respect to SICF was investigated. Non-linear interaction between LICI and RS was observed, while I1-wave timed SICF facilitated all MEP responses of RS by a common offset still preserving the RS. These findings implicate that the underlying mechanism for the observed interaction is likely contributed to the activation of the negative thalamo-cortical feedback loop represented by the RS, most likely at the cortical level.

Thalamic Atrophy Without Whole Brain Atrophy Is Associated With Absence of 2-Year NEDA in Multiple Sclerosis.

Purpose: To study which brain volume measures best differentiate early relapsing MS (RMS) and secondary progressive MS (SPMS) patients and correlate with disability and cognition. To test whether isolated thalamic atrophy at study baseline correlates with NEDA (no evidence of disease activity) at 2 years. Methods: Total and regional brain volumes were measured from 24 newly diagnosed RMS patients 6 months after initiation of therapy and 2 years thereafter, and in 36 SPMS patients. Volumes were measured by SIENAX and cNeuro. The patients were divided into subgroups based on whole brain parenchyma (BP) and thalamic atrophy at baseline. Standard scores (z-scores) were computed by comparing individual brain volumes against healthy controls. A z-score cut-off of -1.96 was applied to separate atrophic from normal brain volumes. The Expanded Disability Status Scale (EDSS) and Symbol Digit Modalities Test (SDMT) were assessed at baseline and at 2 years. Differences in achieving NEDA-3, NEDA-4, EDSS progression, and SDMT change were analyzed between patients with no thalamic or BP atrophy and in patients with isolated thalamic atrophy at baseline. Results: At baseline, 7 SPMS and 12 RMS patients had no brain atrophy, 8 SPMS and 10 RMS patients had isolated thalamic atrophy and 2 RMS and 20 SPMS patients had both BP and thalamic atrophy. NEDA-3 was reached in 11/19 patients with no brain atrophy but only in 2/16 patients with isolated thalamic atrophy (p = 0.012). NEDA-4 was reached in 7/19 patients with no brain atrophy and in 1/16 of the patients with isolated thalamic atrophy (p = 0.047). At 2 years, EDSS was same or better in 16/19 patients with no brain atrophy but only in 5/17 patients with isolated thalamic atrophy (p = 0.002). There was no significant difference in the EDSS, relapses or SDMT between patients with isolated thalamic atrophy and no atrophy at baseline. Conclusion: Patients with isolated thalamic atrophy were at a higher risk for not reaching 2-year NEDA-3 and for EDSS increase than patients with no identified brain atrophy. The groups were clinically indistinguishable. A single measurement of thalamic and whole brain atrophy could help identify patients needing most effective therapies from early on.

Navigated transcranial magnetic stimulation and computed electric field strength reduce stimulator-dependent differences in the motor threshold.

The motor threshold (MT) is a fundamental parameter for evaluating cortical excitability in transcranial magnetic stimulation (TMS) despite remarkable variation, both within, and between subjects. We intended to test whether the variation could be reduced by targeting the stimulation on-line and modeling the TMS-induced electric field on individual MR images. Navigated TMS was used to map the primary motor cortex for the representation area of the thenar muscles (abductor pollicis brevis) and to determine the MT. Thirteen healthy subjects participated in the study. To determine the between-subject variation, the MTs of nine subjects were measured with two different stimulators (comparison study). To study the individual variation, the MT measurement was repeated 20 times in four subjects always using the same stimulator (longitudinal study). In the comparison study, the MTs differed significantly between the two stimulators over all subjects (p<0.001), whereas the electric field strengths did not exhibit significant difference between the stimulators. Both, the MTs, and the electric field strengths showed similar variations, which were greater between subjects (comparison study) than within subjects (longitudinal study). In the comparison study, the distance between the locations of the two different coils on the scalp was significantly greater than the distance between the induced electric field maxima in the brain (p<0.001). We conclude that on-line navigation can be used to reduce the variation caused by different stimulator types and individual subject anatomy. In addition, cortical excitability can be evaluated by using computed electric field strength as well as stimulator-dependent MT.

Factors influencing cortical silent period: optimized stimulus location, intensity and muscle contraction.

Inhibitory silent period (SP) is a transient suppression of voluntary muscle activity after depolarization of representative motor neuronal populations following transcranial magnetic stimulation (TMS). Our aim was to evaluate and present an optimal protocol for the measurement of SP by (1) determining the impact of muscle activation level and stimulus intensity (SI) on the duration of SP, and, (2) studying the relationship between motor evoked potential (MEP) and SP, using targeted stimulus delivery. Single magnetic pulses were focused on the optimal representation area of the thenar musculature on primary motor cortex. We utilized real-time 3D-positioning of TMS-evoked electric field on anatomical structures derived from individual MR-images. The SI varied from 80% to 120% of individual resting motor threshold (MT). Muscle activation levels varied from 20% to 80% of the maximal voluntary contraction (MVC). Contralateral SP lengthened significantly with increasing SI independent of target muscle activation. The peak amplitude of the MEP was affected by SI and force. Latency and duration of the MEP were practically unaffected by SI or force. Focal stimulation at 110-120% MT and approximately 50% MVC (with only negligible need for control) provides most stable and informative SP. MEP should be included in SP as the error from marking the onset diminishes. This study provides a guideline for the consistent measurement of SP, which is applicable when using navigated or traditional TMS.

Navigated TMS combined with EEG in mild cognitive impairment and Alzheimer's disease: a pilot study.

Our aim was to assess the potential of navigated transcranial magnetic stimulation (TMS)-evoked electroencephalographic (EEG) responses in studying neuronal reactivity and cortical connectivity in Alzheimer's disease (AD) and in mild cognitive impairment (MCI). We studied 14 right-handed subjects: five patients with AD, five patients with MCI and four healthy controls. Fifty TMS-pulses at an intensity of 110% of individually determined motor threshold were delivered to the hand area of primary motor cortex (M1) with navigated brain stimulation (NBS). Spreading of primary NBS-evoked neuronal activity was monitored with a compatible 60-channel EEG, and analyzed in time, frequency and spatial-domains. We found significantly reduced TMS-evoked P30 (time-locked response 30 ms after the magnetic stimulation) in the AD subjects. This reduction was seen in the temporo-parietal area ipsilateral to stimulation side as well as in the contralateral fronto-central cortex corresponding to the sensorimotor network, which is anatomically interconnected with the stimulated M1. In addition, there was a significant decrease in the N100 amplitude in the MCI subjects when compared with the control subjects. Thus, the combination of NBS and EEG revealed prominent changes in functional cortical connectivity and reactivity in the AD subjects. This pilot study suggests that the method may provide a novel tool for examining the degree and progression of dementia.

Individual characterization of fast intracortical facilitation with paired biphasic-wave transcranial magnetic stimulation.

We characterized the short-interval intracortical facilitation (SICF) via modulation of transcranial magnetic stimulation (TMS) induced motor evoked potentials (MEPs) using paired-pulse stimulation, and analyzed the interactions with known SICF I-wave behavior. The objective was to optimize individual SICF to enhance TMS effects in motor mapping and therapeutic stimulations. We applied navigated TMS in nine healthy volunteers to study SICF. MEPs were measured for baseline using single-pulse TMS, and subsequently, paired-pulse TMS was applied to study SICF. The interstimulus interval (ISI) between the pulses was varied between 1.2 and 4.3 ms at 0.1 ms intervals. Ten MEPs were measured from three muscles (FDI, APB and ADM) in the dominant hand of the volunteer. We then fitted a 3-peak Gaussian model to the individual paired-pulse MEP vs. ISI curves to characterize each peak by latency, amplitude and width. Individual SICF I-wave interaction characteristics were successfully determined. The average peak latencies were 1.36 (I1-wave), 2.80 (I2-wave) and 4.29 (I3-wave) for the targeted FDI muscle. The peak amplitudes differed depending on the muscle (p = 0.001), with ADM muscle exhibiting greatest SICF effect, but no significant difference between the three peaks. In addition, the peak widths differed between all muscles (p<0.001), second peak being the widest. In conclusion, the individual SICF I-wave interaction characteristics were successfully determined revealing significant differences in peak features. This could enable application of SICF for enhancement of TMS effects in therapy, cortical mapping and basic neuroscience applications.

Transcranial magnetic stimulation modulation of corticospinal excitability by targeting cortical I-waves with biphasic paired-pulses.

BACKGROUND: Transcranial magnetic stimulation (TMS) induced I-wave behavior can be demonstrated at neuronal population level using paired-pulses and by observing short-interval cortical facilitation (SICF). Advancements in stimulator technology have made it possible to apply biphasic paired-pulses to induce SICF. OBJECTIVE: Our aim was to characterize the SICF I-wave interaction by biphasic paired-pulses with the ultimate objective to enhance TMS effects via SICF in various TMS-applications. METHODS: We used biphasic paired-pulses in 15 volunteers to characterize corticospinal SICF using various 1.2-8.0ms inter-stimulus intervals, and measuring SICF input-output response. RESULTS: SICF interaction with the first I-wave (I1) was observed in the output responses (motor evoked potentials; MEPs) in all subjects. Most subjects (≥80%) also exhibited later SICF I-wave interaction. SICF at I1 was present at all applied intensities below 140% of resting motor threshold. At I2, we observed SICF only with intensities just above motor threshold. CONCLUSIONS: Biphasic paired-pulses can reliably induce SICF shown by the facilitatory I-wave interaction, and could therefore be applied with repetitive bursts to enhance responsiveness to TMS.

Infrared thermography reveals effect of working posture on skin temperature in office workers.

INTRODUCTION: Musculoskeletal symptoms related to using traditional computer workstations are common. Quantitative methods for measuring muscle stress and strain are needed to improve ergonomics of workstations. We hypothesize that infrared thermography (IRT) is suited for this purpose. METHODS: This hypothesis was evaluated by estimating muscle activity in upright and traditional working postures with IRT and surface electromyography (sEMG). IRT and sEMG measurements were conducted in 14 female participants with both working postures. First, measurements with the traditional posture were performed. Later, participants had 1 month to adjust to the upright working posture before repeating the measurements. IRT images were acquired before and after a full working day, with sEMG recordings being conducted throughout the measurement days. Participants evaluated their neck pain severity using neck disability index (NDI) questionnaires before the first and after the second measurement day. RESULTS: Spatial variation in upper back temperature was higher (p = 0.008) when working in traditional posture and the upright working posture reduced (p < 0.05) upper back muscle activity. The NDI was significantly lower (p = 0.003) after working in the upright posture. CONCLUSION: IRT was found suitable for evaluating muscle activity and upright working posture to reduce the NDI and muscle activity in the upper back.

Spinal epidural lipomatosis caused by corticosteroid treatment in ulcerative colitis.

Spinal epidural lipomatosis is the result of deposition of unencapsulated fat in the extradural space of the spinal canal. Most commonly, this rare condition is a complication secondary to corticosteroid treatment. We describe a 49-year-old patient with ulcerative colitis who developed paraparesis due to overgrowth of epidural fat tissue. This is the second patient with ulcerative colitis described in the literature who developed symptomatic epidural lipomatosis secondary to corticosteroid treatment. All internists tending patients with chronic diseases that require corticosteroid treatment should be aware of this rare clinical entity.