Reliability of 2D ultrasound imaging associated with transient ShearWave Elastography method to analyze spastic gastrocnemius medialis muscle architecture and viscoelastic properties

PurposeThe aim of the study was to assess the reliability of pennation angle (PA) and muscle thickness (MT) 2D measurements and of shear elastic modulus measurement, using ultrasound imaging (US). Those measurements were made on spastic gastrocnemius medialis muscle at rest and at maximal passive stretching, in post-stroke hemiplegic patients. The paretic side measurements were compared to non-paretic side.Material and methodsFourteen patients took part in 2 inter-session reliability experiments, realized at a 7 days interval by the same operator. The Aixplorer® Supersonic US scanner with the transient ShearWave Elastography (SWE) software was used. The stretching experiments were made manually and controlled by a goniometer.ResultsThe reliability of the 2D measurements was good. The coefficient of variation (CV) was 6.30% for MT measurement at rest, 6.40% and 8.26% for PA at rest and at maximal passive stretching respectively. The reliability of the shear elastic modulus measurement in the sagittal plane was good only at rest with a CV of 9.86%, versus 40.58% at stretching. None of the shear elastic modulus measurements in the axial plane were good. At rest, MT and PA were weaker on the paretic side (14.25±3.12mm and 17.32±5.10°) versus non-paretic side (16.30±3.19mm and 21.08±5.05°) (P<0.0001 and P=0.006). At rest, there was a small difference in the shear elastic modulus between the paretic side and the non-paretic side (5.40±1.67kPa versus 6.20±2.18kPa, P=0.041).DiscussionThis is the first description of muscle spastic structure using SWE with Supersonic Shear Imaging. 2D US associated with SWE shows promise in terms of muscular atrophy quantification and muscle histological quality assessment. These structural properties reflect some of the functional abilities regardless of motor control. It should enable further research on therapies, which impact muscle tissue quality, such as botulinum neurotoxin injections

Adjunct therapies to improve outcomes after botulinum toxin injection in children: A systematic review

BACKGROUND: Botulinum toxin (BTX) injection alone is not sufficient to treat spasticity in children, notably those with cerebral palsy; thus, there is an emerging trend for adjunct therapies to offer greater outcomes than BTX alone. OBJECTIVE: The aim of this systematic review was to evaluate the general effectiveness of adjunct therapies regardless of their nature in children with spasticity. METHODS: Medline, Cochrane and Embase databases were searched from January 1980 to March 15, 2018 for reports of parallel-group trials (randomized controlled trials [RCTs] and non-RCTs) assessing adjunct therapies after BTX injection for treating spasticity in children. Two independent reviewers extracted data and assessed the risk of bias by using the PEDro scale for RCTs and Downs and Black scale (D&amp;B) for non-RCTs. RESULTS: Overall, 20 articles involving 662 participants met the inclusion criteria. The average quality was good for the 16 RCTs (mean PEDro score 7.4 [SD 1.6]) and poor to moderate for the 4 non-RCTs (D&amp;B score 9 to 17). Adjunct therapies consisted of casting/posture, electrical stimulation, resistance training and rehabilitation programmes. Casting associated with BTX injection improved the range of passive and active motion and reduced spasticity better than did BTX alone (9 studies), with a follow-up of 1 year. Resistance training enhanced the quality and performance of muscles without increasing spasticity. Only 3 rehabilitation programmes were studied, with encouraging results for activities. CONCLUSION: Lower-limb posture with casting in children has a high level of evidence, but the long-term efficacy of short-leg casting needs to be evaluated. A comparison between the different modalities of casting is missing, and studies specifically devoted to testing the different kinds of casting are needed. Moreover, the delay to casting after BTX injection is not clear. Data on electrical stimulation are not conclusive. Despite the small number of studies, resistance training could be an interesting adjunct therapy notably to avoid loss of strength after BTX injection. Rehabilitation programmes after BTX injection still need to be evaluated

Size does matter: crocodile mothers react more to the voice of smaller offspring

Parental care is widespread in Archosaurs (birds, crocodilians, dinosaurs and pterosaurs), and this group provides a useful model for the evolution of parent-offspring interactions. While offspring signalling has been well-studied in birds, the modulation of parental care in crocodilians remains an open question. Here we show that acoustic communication has a key role in the dynamics of crocodilian’ mother-offspring relationships. We found embedded information about the emitter’s size in juvenile calls of several species, and experimentally demonstrated that Nile crocodile mothers breeding in the wild are less receptive to the calls of larger juveniles. Using synthetized sounds, we further showed that female’ reaction depends on call pitch, an important cue bearing size information. Changes in acoustic interactions may thus go with the break of maternal care as well as dispersal of juvenile crocodilians. This process could have characterized other archosaurs displaying rapid early growth such as dinosaurs and pterosaurs

Are acoustical parameters of begging call elements of thin-billed prions related to chick condition?

Chicks of burrowing petrels use begging calls to advertise their hunger levels when parents arrived at the nest. In a previous study, adult thin-billed prions Pachyptila belcheri responded to higher begging call rates of their single chick by regurgitating larger meals. We tested whether acoustic parameters of begging call elements may also be involved in signalling. To describe variation in begging, we determined begging session parameters, namely the duration, number of calls and the mean and maximum rate of calling. We then digitised calls and carried out a semi-automatic extraction of six acoustic parameters of call elements, including mean and maximum acoustic frequency, the length of call elements and the location of the maximum frequency and amplitude within calls. Chicks showed strong individual differences in all parameters. While the session parameters were correlated with body condition and with the meal size the chick received, none of the acoustic parameters were related to body condition and provisioning. A cross-fostering experiment showed the same pattern, as only session parameters changed related to an experimentally altered body condition, while acoustical cues appear to play no role in signalling hunger levels. We suggest that this may be explained by the absence of sibling competition in these birds. As parents do not need to decide which chick to feed, immediate information on condition at the time of adult arrival may not be required

Visitor presence and a changing soundscape, alongside environmental parameters, can predict enclosure usage in captive flamingos

This is the final version. Available on open access from Wiley via the DOI in this recordData availability statement: The data that support the findings of this study are available from the corresponding author upon reasonable request. Raw data from this project are available upon reasonable request from the corresponding author.The sound environment of a zoo animal is a complex milieu of animal and human‐generated sounds; coming from the species itself, other species, visitors, keepers and other zoo‐users. Research determining how different components of the sound environment affect animal behaviour is surprisingly lacking but could have real‐world impacts for animal welfare and zoo enclosure design. The current study investigated the effects of the sound environment on two flocks of flamingos housed in open‐air enclosures at British zoos. Measures of how each flock used its enclosure (as a response variable) and environmental variables (Inband Power and Peak Frequency were recorded as characteristics of the sound environment, as well as temperature, humidity and cloud cover, and finally visitor presence—all as potential predictor variables) were made over a 2‐month period. Assessment of space use by zoo animals is often used as a measure of the appropriateness of an exhibit and to understand welfare. Given that flamingo activity is influenced by weather and that the sound environment of the zoo is likely to be influenced by the number and the presence of visitors, it was assumed that these predictor variables would influence where the flamingos were located at different times of the day. As expected, there was a complicated relationship between enclosure use and Inband Power (average spectral density, a measure of sound energy) in both flocks; visitors generated salient sound but other visitor characteristics such as their physical presence may have impacted the movement of the birds around their enclosures. Results show a complex picture where environmental conditions influence flamingo enclosure usage as well as visitor presence and sounds around/in the enclosure. Findings are not consistent between the two flocks, with one flock demonstrating distinct temporal change to enclosure zone occupancy and the other responsive to humidity and cloud cover variation. We believe enclosure use can provide a valuable indication of how birds react to their soundscape; however, our findings suggest more work is needed to unpick the components of captive sound environments, and their relative effects on how animals use their space.Economic and Social Research Council (ESRC

Crocodile egg sounds signal hatching time.

International audienceCrocodilians are known to vocalize within the egg shortly before hatching [1,2]. Although a possible function of these calls - inducing hatching in siblings and stimulating the adult female to open the nest - has already been suggested, it has never been experimentally tested [1-5]. Here, we present the first experimental evidence that pre-hatching calls of Nile crocodile (Crocodylus niloticus) juveniles are informative acoustic signals which indeed target both siblings and mother

Influence of head morphology and natural postures on sound localization cues in crocodilians

International audienc

Author&apos;s personal copy Zoology Acoustic signals of baby black caimans

a b s t r a c t In spite of the importance of crocodilian vocalizations for the understanding of the evolution of sound communication in Archosauria and due to the small number of experimental investigations, information concerning the vocal world of crocodilians is limited. By studying black caimans Melanosuchus niger in their natural habitat, here we supply the experimental evidence that juvenile crocodilians can use a graded sound system in order to elicit adapted behavioral responses from their mother and siblings. By analyzing the acoustic structure of calls emitted in two different situations (&apos;undisturbed context&apos;, during which spontaneous calls of juvenile caimans were recorded without perturbing the group, and a simulated &apos;predator attack&apos;, during which calls were recorded while shaking juveniles) and by testing their biological relevance through playback experiments, we reveal the existence of two functionally different types of juvenile calls that produce a different response from the mother and other siblings. Young black caimans can thus modulate the structure of their vocalizations along an acoustic continuum as a function of the emission context. Playback experiments show that both mother and juveniles discriminate between these &apos;distress&apos; and &apos;contact&apos; calls. Acoustic communication is thus an important component mediating relationships within family groups in caimans as it is in birds, their archosaurian relatives. Although probably limited, the vocal repertoire of young crocodilians is capable of transmitting the information necessary for allowing siblings and mother to modulate their behavior

Parent-offspring communication in the Nile crocodile <i>Crocodylus niloticus</i>: do newborns' calls show an individual signature?

Young Nile crocodiles Crocodylus niloticus start to produce calls inside the egg and carry on emitting sounds after hatching. These vocalizations elicit maternal care and influence the behaviour of other juveniles. In order to investigate the acoustic structure of these calls, focusing on a possible individual signature, we have performed acoustic analyses on 400 calls from ten young crocodiles during the first 4 days after hatching. Calls have a complex acoustic structure and are strongly frequency modulated. We assessed the differences between the calls of the individuals. We found a weak individual signature. An individual call-based recognition of young by the mother is thus unlikely. In other respects, the call acoustic structure changes from the first to the fourth day after hatching: fundamental frequency progressively decreases. These modifications might provide important information to the mother about her offspring—age and size—allowing her to customize her protective care to best suit the needs of each individual