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Federica Ginanneschi

Bio: Federica Ginanneschi is an academic researcher from University of Siena. The author has contributed to research in topics: Carpal tunnel syndrome & Ulnar nerve. The author has an hindex of 23, co-authored 88 publications receiving 1718 citations.


Papers
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TL;DR: In CLBP patients, postural stability under challenging conditions is maintained by an increased sway in AP direction, which may underlie a dysfunction of the peripheral proprioceptive system or the central integration of proprioception information.

221 citations

Journal ArticleDOI
TL;DR: The incidence of ulnar neuropathy at the elbow was higher in males than females and about one-thirteenth that reported for CTS in part of the present geographic area, and showed an increasing trend with decade of age.

211 citations

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TL;DR: Early sensory processing at cortical level is changed during tonic muscle pain, mainly for those components which may be theoretically involved in proprioceptive afferent elaboration during movements, in combination with those post-central components peaking after the first activation of the primary sensory cortex.

121 citations

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TL;DR: It is concluded that nociceptive volleys arising from dorsal foot muscles facilitate the activity of interneurones intercalated in pathways responsible for presynaptic inhibition of Sol Ia fibres.

90 citations

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TL;DR: In this paper, the authors examined whether the recruitment properties of the corticospinal pathway to intrinsic hand muscles are influenced by variations of the shoulder joint angle, and they found that 30 degrees abduction significantly depressed MEP size and prolonged MEP latency in comparison with 30 degrees shoulder adduction.
Abstract: We examined whether the recruitment properties of the corticospinal pathway to intrinsic hand muscles are influenced by variations of the shoulder joint angle. Abductor digiti minimi (ADM) motor evoked potentials (MEPs) in response to transcranial magnetic stimulation were examined during different static positions of the shoulder joint in the horizontal plane from 30 degrees adduction to 30 degrees abduction with respect to the neutral position at 0 degrees, while elbow and wrist joints were constrained statically at 90 degrees and 180 degrees respectively. We found that 30 degrees abduction of the shoulder significantly depressed MEP size and prolonged MEP latency in comparison with 30 degrees shoulder adduction. The neutral shoulder angle position (at 0 degrees ) significantly reduced MEP size but had no effect on MEP latency in comparison with 30 degrees shoulder abduction. The input-output relationship between MEP size and stimulus intensity was sigmoidal. The plateau value and maximum slope were significantly lower at 30 degrees abduction than at 30 degrees adduction of the shoulder. However, the threshold value did not differ significantly between the two positions. To differentiate excitability changes at cortical versus subcortical sites, intracortical inhibition (ICI) and intracortical facilitation (ICF) were assessed using a paired-magnetic pulse paradigm. A significant decrease in ICF was observed after changing shoulder position from 30 degrees adduction to 30 degrees abduction. In contrast, no variation in the amount of ICI occurred in relation to the same changes in shoulder position. ADM F-waves elicited by electrical stimulation of the ulnar nerve at the wrist were significantly decreased at 30 degrees shoulder abduction in comparison with 30 degrees adduction. A similar pattern was observed in one subject in whom the H-reflex could be exceptionally elicited in ADM. We conclude that shoulder position influences the recruitment efficiency (gain) of the corticospinal volleys to motoneurons of intrinsic hand muscles. It is proposed that activity of peripheral receptors signalling static shoulder position influences corticomotor excitability of hand muscles both at the cortical and at the spinal level. This modulation may be functionally relevant when reaching to grasp objects.

76 citations


Cited by
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Journal ArticleDOI
TL;DR: Evidence for "central" fatigue and the neural mechanisms underlying it are reviewed, together with its terminology and the methods used to reveal it.
Abstract: Muscle fatigue is an exercise-induced reduction in maximal voluntary muscle force. It may arise not only because of peripheral changes at the level of the muscle, but also because the central nervous system fails to drive the motoneurons adequately. Evidence for “central” fatigue and the neural mechanisms underlying it are reviewed, together with its terminology and the methods used to reveal it. Much data suggest that voluntary activation of human motoneurons and muscle fibers is suboptimal and thus maximal voluntary force is commonly less than true maximal force. Hence, maximal voluntary strength can often be below true maximal muscle force. The technique of twitch interpolation has helped to reveal the changes in drive to motoneurons during fatigue. Voluntary activation usually diminishes during maximal voluntary isometric tasks, that is central fatigue develops, and motor unit firing rates decline. Transcranial magnetic stimulation over the motor cortex during fatiguing exercise has revealed focal cha...

3,200 citations

Journal ArticleDOI
TL;DR: It is shown that the anatomical substrate of this recurrent message passing is a hierarchical system consisting of functionally asymmetric driving (ascending) and modulatory (descending) connections: an arrangement that is almost exactly recapitulated in the motor system, in terms of its laminar, topographic and physiological characteristics.
Abstract: The descending projections from motor cortex share many features with top-down or backward connections in visual cortex; for example, corticospinal projections originate in infragranular layers, are highly divergent and (along with descending cortico-cortical projections) target cells expressing NMDA receptors. This is somewhat paradoxical because backward modulatory characteristics would not be expected of driving motor command signals. We resolve this apparent paradox using a functional characterisation of the motor system based on Helmholtz’s ideas about perception; namely, that perception is inference on the causes of visual sensations. We explain behaviour in terms of inference on the causes of proprioceptive sensations. This explanation appeals to active inference, in which higher cortical levels send descending proprioceptive predictions, rather than motor commands. This process mirrors perceptual inference in sensory cortex, where descending connections convey predictions, while ascending connections convey prediction errors. The anatomical substrate of this recurrent message passing is a hierarchical system consisting of functionally asymmetric driving (ascending) and modulatory (descending) connections: an arrangement that we show is almost exactly recapitulated in the motor system, in terms of its laminar, topographic and physiological characteristics. This perspective casts classical motor reflexes as minimising prediction errors and may provide a principled explanation for why motor cortex is agranular.

583 citations

Journal ArticleDOI
TL;DR: The best indication that central fatigue is important during submaximal tasks is the disproportionate increase in subjects' perceived effort when maintaining a low target force.
Abstract: Magnetic and electrical stimulation at different levels of the neuraxis show that supraspinal and spinal factors limit force production in maximal isometric efforts ("central fatigue"). In sustained maximal contractions, motoneurons become less responsive to synaptic input and descending drive becomes suboptimal. Exercise-induced activity in group III and IV muscle afferents acts supraspinally to limit motor cortical output but does not alter motor cortical responses to transcranial magnetic stimulation. "Central" and "peripheral" fatigue develop more slowly during submaximal exercise. In sustained submaximal contractions, central fatigue occurs in brief maximal efforts even with a weak ongoing contraction (<15% maximum). The presence of central fatigue when much of the available motor pathway is not engaged suggests that afferent inputs contribute to reduce voluntary activation. Small-diameter muscle afferents are likely to be activated by local activity even in sustained weak contractions. During such contractions, it is difficult to measure central fatigue, which is best demonstrated in maximal efforts. To show central fatigue in submaximal contractions, changes in motor unit firing and force output need to be characterized simultaneously. Increasing central drive recruits new motor units, but the way this occurs is likely to depend on properties of the motoneurons and the inputs they receive in the task. It is unclear whether such factors impair force production for a set level of descending drive and thus represent central fatigue. The best indication that central fatigue is important during submaximal tasks is the disproportionate increase in subjects' perceived effort when maintaining a low target force.

543 citations

Journal Article
TL;DR: As one of the part of book categories, nerves and nerve injuries always becomes the most wanted book.
Abstract: If you really want to be smarter, reading can be one of the lots ways to evoke and realize. Many people who like reading will have more knowledge and experiences. Reading can be a way to gain information from economics, politics, science, fiction, literature, religion, and many others. As one of the part of book categories, nerves and nerve injuries always becomes the most wanted book. Many people are absolutely searching for this book. It means that many love to read this kind of book.

466 citations

Journal ArticleDOI
TL;DR: The high prevalence of carpal tunnel syndrome, its effects on quality of life, and the cost that disease burden generates to health systems make it important to identify the research priorities that will be resolved in clinical trials.
Abstract: Carpal tunnel syndrome is the most common peripheral nerve entrapment syndrome worldwide. The clinical symptoms and physical examination findings in patients with this syndrome are recognised widely and various treatments exist, including non-surgical and surgical options. Despite these advantages, there is a paucity of evidence about the best approaches for assessment of carpal tunnel syndrome and to guide treatment decisions. More objective methods for assessment, including electrodiagnostic testing and nerve imaging, provide additional information about the extent of axonal involvement and structural change, but their exact benefit to patients is unknown. Although the best means of integrating clinical, functional, and anatomical information for selecting treatment choices has not yet been identified, patients can be diagnosed quickly and respond well to treatment. The high prevalence of carpal tunnel syndrome, its effects on quality of life, and the cost that disease burden generates to health systems make it important to identify the research priorities that will be resolved in clinical trials.

428 citations