Kinematics of head movement and onset of sternocleidomastoid muscle activity in simulated low-velocity rear-end impacts

2005 ◽  
Vol 99 (4) ◽  
pp. 438-439
Author(s):  
I.A. Hernández ◽  
K. Fyfe ◽  
G. Heo ◽  
I. Ikram ◽  
P.W. Major
Keyword(s):  
Muscle Activity ◽  
Head Movement ◽  
Sternocleidomastoid Muscle ◽  
Low Velocity

Head Movement Evoked By Electrical Stimulation in the Supplementary Eye Field of the Rhesus Monkey

2005 ◽  
Vol 94 (6) ◽  
pp. 4502-4519 ◽  
Author(s):  
L. Longtang Chen ◽  
Mark M. G. Walton
Keyword(s):  
Head Movement ◽  
Direct Evidence ◽  
Head Movements ◽  
Eye Position ◽  
Low Velocity ◽  
Gaze Shifts ◽  
The Gaze ◽  
Supplementary Eye Field ◽  
Combined Movements ◽  
Eye Field

Although the supplementary eye field (SEF) has been implicated in the control of head movements associated with gaze shifts, there is no direct evidence that SEF plays a role in the generation of head movements independent of gaze. If the SEF does, varying the duration of stimulation should selectively alter the head-movement kinematics during the postgaze-shift period. The duration of the stimulation was manipulated while head-unrestrained monkeys maintained stable head forward postures. The initial positions of the eyes in the orbits were systematically varied. Although combined movements of the eyes and head were produced in the majority of the trials, head movements were sometimes evoked in the absence of gaze shifts. These head-alone movements were most frequent when the initial eye position was contralateral to the stimulated side. When the stimulation produced eye and head movements, gaze onset was sometimes preceded by a relatively low-velocity phase of the head movement. Evoked head movements were primarily horizontal, unlike the gaze shifts, which typically had vertical components that varied according to the initial positions of the eyes in the orbits. The postgaze-shift head movements tended to be of low velocity and in many cases persisted until stimulation offset. In general, prolonging the stimulation resulted in improved centering of the eyes in the orbits. These findings suggest that, in addition to its previously described role in the generation of coordinated eye-head gaze shifts, the SEF is also involved in the control of head movements in the absence of a change of gaze.

Sternocleidomastoid muscle activity in keeping the head stable while slalom driving

2011 ◽  
Author(s):  
Rencheng Zheng ◽  
Kimihiko Nakano ◽  
Yuji Okamoto ◽  
Masanori Ohori ◽  
Shigeyuki Hori ◽  
...  
Keyword(s):  
Muscle Activity ◽  
Sternocleidomastoid Muscle

scholarly journals Muscle Characteristics in Pediatric Hereditary Spastic Paraplegia vs. Bilateral Spastic Cerebral Palsy: An Exploratory Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Nathalie De Beukelaer ◽  
Lynn Bar-On ◽  
Britta Hanssen ◽  
Nicky Peeters ◽  
Sandra Prinsen ◽  
...  
Keyword(s):  
Cerebral Palsy ◽  
Muscle Activity ◽  
High Velocity ◽  
Exploratory Study ◽  
Spastic Cerebral Palsy ◽  
Typically Developing ◽  
Spastic Paraplegia ◽  
Ankle Clonus ◽  
Low Velocity ◽  
Patient Groups

Hereditary spastic paraplegia (HSP) is a neurological, genetic disorder that predominantly presents with lower limb spasticity and muscle weakness. Pediatric pure HSP types with infancy or childhood symptom onset resemble in clinical presentation to children with bilateral spastic cerebral palsy (SCP). Hence, treatment approaches in these patient groups are analogous. Altered muscle characteristics, including reduced medial gastrocnemius (MG) muscle growth and hyperreflexia have been quantified in children with SCP, using 3D-freehand ultrasound (3DfUS) and instrumented assessments of hyperreflexia, respectively. However, these muscle data have not yet been studied in children with HSP. Therefore, we aimed to explore these MG muscle characteristics in HSP and to test the hypothesis that these data differ from those of children with SCP and typically developing (TD) children. A total of 41 children were retrospectively enrolled including (1) nine children with HSP (ages of 9–17 years with gross motor function levels I and II), (2) 17 age-and severity-matched SCP children, and (3) 15 age-matched typically developing children (TD). Clinically, children with HSP showed significantly increased presence and severity of ankle clonus compared with SCP (p = 0.009). Compared with TD, both HSP and SCP had significantly smaller MG muscle volume normalized to body mass (p ≤ 0.001). Hyperreflexia did not significantly differ between the HSP and SCP group. In addition to the observed pathological muscle activity for both the low-velocity and the change in high-velocity and low-velocity stretches in the two groups, children with HSP tended to present higher muscle activity in response to increased stretch velocity compared with those with SCP. This exploratory study is the first to reveal MG muscle volume deficits in children with HSP. Moreover, high-velocity-dependent hyperreflexia and ankle clonus is observed in children with HSP. Instrumented impairment assessments suggested similar altered MG muscle characteristics in pure HSP type with pediatric onset compared to bilateral SCP. This finding needs to be confirmed in larger sample sizes. Hence, the study results might indicate analogous treatment approaches in these two patient groups.

scholarly journals Conduction studies of phrenic nerve in healthy children

2018 ◽  
Vol 8 (2) ◽  
pp. 53-58 ◽  
Author(s):  
V. B. Voitenkov ◽  
V. N. Komantsev ◽  
N. V. Skripchenko ◽  
E. V. Ekusheva ◽  
A. V. Klimkin ◽  
...  
Keyword(s):  
Phrenic Nerve ◽  
Muscle Activity ◽  
Standard Procedure ◽  
Sternocleidomastoid Muscle ◽  
Healthy Children ◽  
Normative Database ◽  
M Wave ◽  
Mean Values ◽  
Neurophysiological Data ◽  
Wave Latency

Background. Unlike parameters of phrenic nerve conduction in healthy adults characterized by stability, in children variations with age are observed. The objective is to investigate the M-wave latency and amplitude in electroneurographic (ENG) examination of the phrenic nerve in healthy children of different ages for development of a normative database of neurophysiological data.Materials and methods. 48 healthy children (28 girls and 20 boys) were examined. Mean age was 9.19 ± 5.43 years (1–18 years). ENG examination of the phrenic nerve was performed with the modified standard procedure of stimulation at the level of the outer margin of the lower third of the sternocleidomastoid muscle with registration of M-wave from standard diaphragm point and parallel registration of the muscle activity from m.deltoideus and m.serratus anterior.Results. Mean values of the M-response latency were 5.64 ± 1.25 ms, amplitude – 0.66 ± 0.34 mV. For age-differentiated subgroups 1–2 years (n = 7), 3–5 years (n = 9), 6–12 years (n = 15), and 13–18 years (n = 17), the latency was 4.96 ± 1.94; 5.01 ± 1.13; 5.42 ± 0.84, and 6.44 ± 1.43 ms, respectively; the amplitude was 1.01 ± 0.37; 0.87 ± 0.31; 0.61 ± 0.24, and 0.45 ± 0.21 mV, respectively. The M-response amplitude values in children aged 1–2 years significantly differed from the values in children aged 6–12 and 13–18 years.Conclusion. ENG examination of the phrenic nerve is a technically uncomplicated procedure, and the obtained data is easy to interpret. During phrenic nerve ENG in children, it is necessary to take age variability of the M-wave latency and amplitude into account. The M-wave amplitude in healthy toddlers (1–2 years old) was significantly lower than in children aged 6–18 years.

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