Postural Reactions Research Articles

Evaluation of gabapentin administration on neurologic examination in 2 different age groups of healthy cats.

Gabapentin is often administered PO for preappointment or in-hospital anxiolysis in cats. A previous study reported mild changes on the neurologic examination after administration. Investigate the effects of gabapentin on anxiety, sedation, compliance, and neurologic examination in 2 age groups of cats. Thirty-one young cats and 12 geriatric cats perceived by their owners to be healthy and neurologically normal. Prospective double-blinded clinical crossover study. Assessment of baseline sedation and anxiety was performed before initial neurologic examinations and after gabapentin administration (100 mg/cat). Assessments were repeated 90 to 120 minutes after administration. Ease of handling pregabapentin and postgabapentin was assessed in the younger cats. All examinations were performed by a board-certified veterinary neurologist and scoring of examinations was performed by a different, masked board-certified neurologist. Sixteen cats (50%) in the younger cohort and 6 cats (50%) in the geriatric cohort exhibited an increase in their overall neurologic examination score postgabapentin administration, mainly through new or progressive postural reaction deficits and gait changes. Anxiety and sedation scores were significantly changed in the geriatric population (P < .01, P = .004, respectively); however, only sedation scores were significantly increased in the younger cats after gabapentin administration (P = .004). All study participants showed mild neurologic changes after gabapentin administration, most markedly noted in the geriatric population. Dose reduction of gabapentin for preappointment anxiolysis and neurologic examination in geriatric patients should be considered.

Post-Concussion Sleep Quality Association With Dual-Task Postural Stability, Cognition, And Reaction Time Among Adolescents

Post-Concussion Sleep Quality Association With Dual-Task Postural Stability, Cognition, And Reaction Time Among Adolescents

Clinical and magnetic resonance imaging features of unilateral thalamic porencephaly in a dog

AbstractA 1‐year‐3‐month‐old, female, neutered labrador retriever was presented with a history of circling behaviour since 2 months of age and a recently detected blindness affecting its right eye. Neurological examination revealed a left‐sided head tilt, compulsive tight circling towards the left, postural reaction deficits in the right thoracic and pelvic limbs, absent menace response in the right eye and ventral positional strabismus of the left eye. The neurological examination findings were localised to the left thalamus. Magnetic resonance imaging of the head revealed porencephaly involving the left dorsal aspect of the thalamus. Furthermore, reduced volume of the left rostral colliculus, crus cerebri and optic chiasm, alongside marked thinning of the left cerebral hemispheric white matter tracts with associated left lateral ventriculomegaly, were present. Based on magnetic resonance imaging features and clinical history, a congenital or perinatal encephaloclastic porencephaly with secondary hypoplasia or atrophy of the associated thalamic projection pathways was prioritised.

Treatment of hemihydranencephaly in a cat with ventriculoperitoneal shunt

Hemihydranencephaly is extremely rare in cats. In this case report, the aim is to share data on the diagnosis and treatment of a hemihydranencephaly in a cat. This case report is for an 1 year old, 3 kg, male, Scottish fold cat. The cat was brought in by its owner with behavioural changes and decreased activity since birth. Cranial nerve examination revealed that threat reflex and lateral palpebral reflex were decreased and corneal reflex was delayed. Spinal reflex examination revealed a decreased patellar reflex and proprioceptive deficit in all extremities in the postural reaction test. As a result of the tests, a cranial lesion was suspected. Magnetic resonance imaging revealed that the right cerebral hemisphere and ependyma were absent and instead were filled with fluid. In light of the findings, the patient was diagnosed with a hemihydranencephaly. Furosemide, and prednisone were used for medical treatment. However, despite a week of medical treatment, no improvement was observed. Ventriculoperitoneal shunt placement was preferred as the surgical method. Although all of the patient's neurological findings did not disappear in the postoperative period, they improved. A cat with haemihydraocephaly was successfully treated with ventriculoperitoneal shunt for the first time.

The influence of balance support base manipulation on the kinematics of lower limbs during single-legged squats in people with patellofemoral pain

BackgroundGiven that people with patellofemoral pain (PFP) exhibit deficits in postural control, certain postural reactions may be associated with movement alterations in this population. Therefore, the objective of the present study was to investigate whether manipulation of the support base for balance maintenance could lead to different patterns of lower limb kinematics in people with PFP during single-legged squats. MethodsFourteen participants with PFP and 14 asymptomatic controls were first assessed performing single-legged squats freely, and then while holding a stick to provide stabilization during the task. Center of pressure (CoP) behavior and movements of the hip, knee, ankle in the sagittal, frontal, and transverse planes were evaluated. ResultsFor the participants with PFP, the use of support led to a reduction in the magnitude of CoP oscillation compared to free squatting, with effect sizes ranging from small to large, but no significant differences were found for the kinematic variables. No significant differences were observed for CoP or kinematic variables in the comparisons between squat conditions in asymptomatic controls. ConclusionIn summary, performing single-legged squats in a more stabilized condition did not influence lower limb movements in people with PFP.

Effect of a juggling-based physical activity on postural stability, reaction time, and attention focus in older adults: a randomized crossover study

BackgroundIn the aging society, more attention is paid to the promotion of forms of physical activity that can improve postural stability and cognitive functioning. In this context, the importance of combined exercises, requiring simultaneous physical and cognitive involvement, is emphasized. Juggling seems to be a form of activity that is both cognitively and physically demanding. The purpose of this study was to determine the effect of additional juggling exercise on postural stability and cognitive abilities in healthy, physically active older adults.MethodsTwenty-six healthy and physically active older adults (70.08±4.40 years old) were included in a randomized crossover study. The addition of juggling three times a week during four weeks was the main intervention (one period), while the control phase included four weeks with no addition of juggling (second period). Measurements of postural stability and cognitive abilities were performed before and after each period. For the purpose of postural stability assessment, a velocity of center of pressure with root mean square, area 95 percentile, medio-lateral and anterior-posterior range of motion were measured. Center of pressure signals were obtained using an AccuGait™ System force plate in three conditions: free standing, dual-task and limits of stability. The Vienna Test System was used for the assessment of selected cognitive abilities. A battery of reaction time tests and Cognitrone test were used for this purpose.ResultsA significant interaction effect of intervention and time was observed in the postural stability dual-task condition in the root mean square of the center of pressure velocity in the advantage of the juggling period (medio-lateral: F=14.83, p<.01, ƞp2=.37; anterior-posterior: F=26.30, p<.01, ƞp2=.51). Additionally, moderate effect sizes were observed in the velocity of the center of pressure and variability of simple reaction time measurements, but without statistical significance.ConclusionsThe results of this study indicate that the implementation of juggling activity in everyday life may have positive effects on cognitive abilities and postural stability in healthy, physically active older adults, but the true effect may be low to moderate.Trial registrationThe study was registered retrospectively (30.10.2023) at ClinicalTrials.gov (NCT06108713).

Implications of Stabilometric Assessment in Determining Functional Deficits in Patients with Severe Knee Osteoarthritis: Observational Study.

Background: Osteoarthritis is one of the most frequent joint disorders in the world. The specialists in the field strongly support the role of physical exercise as a key component in the holistic management of arthrosis. The aim of the current study was to identify and assess the functional deficit of these patients and to identify means to alleviate it through pre-surgery physiotherapy programs. Methods: The study was conducted on two samples of patients: a witness sample, encompassing 126 subjects without pathologies at the level of their lower limbs, and a study sample, formed of 116 subjects diagnosed with severe gonarthrosis with total knee arthroplasty indication. The assessment protocol was accomplished with the GPS 400 stabilometric platform. Results: The barycenter differences within the support polygon, recorded for the two samples within sagittal deviation, emphasize that the barycenter shifting mainly towards the healthy lower limb will demand, from the individual, more intense rebalancing postural reactions that will place the center-of-gravity projection in the sagittal plane, closer to the central area of the support polygon. Conclusions: In the case of gonarthrosis and other joint disorders, the use of functional testing to assess body weight distribution and center-of-gravity imbalances represents a promising direction in the research on and management of these disorders, providing essential information for functional diagnosing and thus enabling the elaboration and monitoring of individualized functional rehabilitation plans.

Multitasking across the lifespan in different task contexts

We assessed lifespan development of multitasking in a sample of 187 individuals aged 8–82 years. Participants performed a visuo-spatial working memory (VSWM) task together with either postural control or reaction time (RT) tasks. Using criterion-referenced testing we individually adjusted difficulty levels for the VSWM task to control for single-task differences. Age-differences in single-task performances followed U-shaped patterns with young adults outperforming children and older adults. Multitasking manipulations yielded robust performance decrements in VSWM, postural control and RT tasks. Presumably due to our adjustment of VSWM challenges, costs in this task were small and similar across age groups suggesting that age-differential costs found in earlier studies largely reflected differences already present during single-task performance. Age-differences in multitasking costs for concurrent tasks depended on specific combinations. For VSWM and RT task combinations increases in RT were the smallest for children but pronounced in adults highlighting the role of cognitive control processes. Stabilogram diffusion analysis of postural control demonstrated that long-term control mechanisms were affected by concurrent VSWM demands. This interference was pronounced in older adults supporting concepts of compensation or increased cognitive involvement in sensorimotor processes at older age. Our study demonstrates how a lifespan approach can delineate the explanatory scope of models of human multitasking.

The relationship of limited mobility of the cervical spinewith postural and mental reactions of students

Introduction: Previous studies have found that, in addition to the general factors for the occurrence of pain and reduced mobility of the cervical spine, the use of electronic devices promotes these, the excessive use of which can also lead to the occurrence of depressive symptoms in students. The aim of this study was to determine the mobility limitation of the cervical spine in students with reported neck pain, to determine the degree of disability and depression due to neck pain, to determine the correlation of mobility limitation of the cervical spine with the degree of disability and depression of students, and to determine the correlation of the degree of disability with the degree of depression. Methods: The research was conducted as a cross-sectional study from May to July 2021 at the University of Zenica in four faculties. The study used the General Questionnaire and two standardized questionnaires to assess disability due to neck pain (Index of Disability due to Neck Pain) and the degree of depression (patient health questionnaire). Results: A total of 147 students with reported neck pain participated in the study. A limitation of mobility was found in 30.6% of the students in flexion, 25.2% in rotation, 23.8% in lateral flexion, and 20.4% on extension. Mild disability due to neck pain was found in 58.5% of students, moderate in 23.8%, and severe in 2.7%. 45.6% of the students had mild depression, 18.4% had moderate depression, and 5.4% had severe depression.Conclusion: Restricted flexion and rotation are more common than restricted lateral flexion and extension of the cervical spine. About half of the students who reported neck pain had a mild degree of disability and mild depression. A strong positive correlation was found between the degree of disability and depression in students with neck pain.

Sensory function and somatosensorial system changes according to visual acuity and throwing techniques in goalball players: A cross-sectional study.

The somatosensory system is a complect sensory system that differentiates individual athletes. The aim of this study is to investigate the effect of visual acuity level on throwing technique, proprioceptive sense of the shoulder joint, light touch and two-point discrimination sense of the upper extremity, and sensory function (postural control and reaction time) in visually impaired goalball players. Goalball players who have different visual acuities B1(unable to perceive light or recognize its shape); B2 (has a visual field of less than 5 degrees and can recognize shapes); B3 (visual field greater than 5 degrees and less than 20 degrees) participated in the study. The sensorial system was evaluated with proprioceptive sense of the shoulder joint and sensory tests (light touch and two-point discrimination sense of the dominant hand.). Sensory function (postural control and reaction time) was evaluated with the flamingo balance test, functional reach test, and pro-agility test. The goalball players' throwing technique was questioned. Seventeen male players, those aged 20-30 (20.8±3.9 years) who have been professionally engaged in goalball for at least three years (58.7-37.8 months) participated. Shoulder internal rotation joint position sense and the flamingo balance test were found to be different in the group with B1 visual acuity than in the group with B3 visual acuity (p = 0.042* and 0.028 respectively). There was no difference between groups with B1-B2 visual acuity (p = 0.394 and p = 0.065) and between groups with B2-B3 visual acuity (p = 0.792 and p = 0.931). There was no difference in the groups in terms of sensory tests and reaction time (p> 0.05). In goalball, joint position sense is related to throwing techniques. Although there is a general acceptance that other sensory systems should work harder to compensate for the sense of vision, fear of falling, athlete's branch year, sports year, muscle strength, and general physical condition of the athlete may affect the measurements made, especially in the dynamic position.

An Augmented Reality Rifle Qualification Test for Return-to-Duty Assessment in Service Members.

Variability in return-to-duty (RTD) decision-making following mild traumatic brain injury (mTBI) is a threat to troop readiness. Current RTD assessments lack military-specific tasks and quantitative outcomes to inform stakeholders of a service member's (SM) capacity to successfully perform military duties. Augmented reality (AR), which places digital assets in a user's physical environment, provides a technological vehicle to deliver military-relevant tasks to a SM to be used in the RTD decision-making process. In addition to delivering digital content, AR headsets provide biomechanical data that can be used to assess the integrity of the central nervous system in movement control following mTBI. The objective of this study was to quantify cognitive and motor performance on an AR rifle qualification test (RQT) in a group of neurologically healthy military SMs. Data were collected from 111 healthy SMs who completed a basic (single-task) and complex (dual-task) RQT with a simulated M4 rifle. The complex scenario required the SM to perform the RQT while simultaneously answering arithmetic problems. Position data from the AR headset were used to capture postural sway, and the built-in microphone gathered responses to the arithmetic problems. There were no differences in the number of targets hit, trigger pull reaction time, and transition time from kneeling to standing between the basic and complex scenarios. A significant worsening in postural sway following kneel-to-stand transition was observed in the complex scenario. The average reaction time to answer the arithmetic problems was nearly 2 times slower than the average reaction time to pull the trigger to a displayed target in the complex scenario. The complex scenario provoked dual-task interference in SMs as evidenced by worsening postural sway and reaction time differences between the cognitive and motor tasks. An AR RQT provides objective and quantitative outcomes during a military-specific task. Greater precision in evaluating cognitive and motor performance during a military-relevant task has the potential to aid in the detection and management of SMs and their RTD following MTBI.

Neurological examination of clinically healthy pigeons (Columba livia domestica), mute swans (Cygnus olor), common buzzards (Buteo buteo), common kestrels (Falco tinnunculus) and northern goshawks (Accipiter gentilis).

A neurological examination is essential for determining the localisation of neurological lesions. However, in avian species, quantitative data regarding the practicability and feasibility of neurological tests are very limited. Therefore, the aim of this study was to establish normative data for the neurological examination of clinically healthy birds of different species. Forty-two domestic and feral pigeons (Columba livia domestica), 42 mute swans (Cygnus olor), 12 common buzzards (Buteo buteo), 24 common kestrels (Falco tinnunculus) and six northern goshawks (Accipiter gentilis) were examined. All birds underwent a predefined neurological examination. Interobserver variations between three examiners were investigated in 11 pigeons and 11 mute swans. All postural reaction tests, except for the drop and flap reaction in mute swans, provoked a consistent response in pigeons and mute swans, whereas postural reaction tests of the legs in raptors were often not performable. Cranial nerve tests and most of the spinal reflexes revealed variable responses in all birds. The gastrocnemius reflex was not provokable in any bird. Interobserver agreement was almost perfect (Gwet's AC1 coefficient ≥0.81) for 16 of 21 parameters in the examination in pigeons and for 14 of 21 in mute swans. The inclusion of free-ranging birds, which were not used to handling and for which limited information regarding age, history of previous diseases, etc. was available, may have influenced the results. The normative neurological examination data provided in this study will help improve clinicians' interpretation of neurological examinationresults in the respective bird species.

Evaluation of neurologic testing in guinea pigs (Cavia porcellus)

BackgroundUp-to-date, specialized literature provides very little information on performing and interpreting clinical neurological tests on small mammals, particularly guinea pigs. MethodsTwo clinical neurologists performed separate neurological examinations of 25 guinea pigs. The structure of the examination was similar to those performed in other companion animals and included hands-off examination, postural reaction tests, cranial nerve tests, and spinal reflex tests. Each test was evaluated for feasibility, reproducibility, and associated stress level for the animals. ResultsThe following tests revealed an excellent ability to elicit the expected response: hopping reaction in the thoracic limbs, wheelbarrowing and hemiwalking, medial and lateral palpebral reflex, auricular sensitivity, maxillary sensitivity, horizontal oculocephalic reflex, tone of the jaw, voluntary movement of the tongue, and direct pupillary light reflex. On the other hand, a poor ability to elicit the expected response was observed in the following tests: visual paw replacement of the thoracic limbs, tactile paw replacement in both thoracic and pelvic limbs, paper test for thoracic and pelvic limbs, mandibular sensitivity, vertical oculocephalic reflex, menace response, patellar reflex, cutaneous trunci reflex, and perineal reflex. The most reliable spinal reflex test with a good ability to elicit the expected response was the withdrawal reflex for both thoracic and pelvic limbs. The guinea pigs experienced the most stress during the spinal reflex tests. ConclusionIt is possible to apply several clinical neurological tests on guinea pigs and produce meaningful results. However, certain tests elicited high stress responses in the animals and should therefore only be used if necessary. Based on the results, we propose a possible protocol for neurological examination in guinea pigs. Clinical relevanceThis is the first study to evaluate a full range of clinical neurological tests performed on guinea pigs. The results of this study could lead to a better understanding of lesion localization and serve as a basis for further diagnostic and therapies in guinea pigs with neurological diseases.

Postural control deficits due to bilateral pyramidal tract lesions exemplified by hereditary spastic paraplegia (HSP) originate from increased feedback time delay and reduced long-term error corrections.

Pyramidal tract lesions determine the clinical syndrome of Hereditary Spastic Paraplegia (HSP). The clinical impairments of HSP are typically exemplified by their deficits in mobility, leading to falls and injuries. The first aim of this study was to identify the cause for postural abnormalities caused by pyramidal tract lesions in HSP. The second aim was to specify the effect of treadmill training for postural abnormalities. We examined nine HSP patients before and after treadmill training, as well as nine healthy control subjects during perturbed and unperturbed stance. We found that HSP was associated with larger sway amplitudes and velocities. Body excursions following platform tilts were larger, and upper body excursions showed a phase lead. Model-based analysis detected a greater time delay and a reduced long-term error correction of postural reactions in the center of mass. HSP patients performed significantly better in clinical assessments after treadmill training. In addition, treadmill training reduced sway amplitudes and body excursions, most likely by increasing positional and velocity error correction gain as a compensatory mechanism, while the time delay and long-term error correction gain remained largely unaffected. Moreover, the upper body's phase lead was reduced. We conclude that HSP leads to very specific postural impairments. While postural control generally benefits from treadmill training, the effect seems to mainly rely on compensatory mechanisms, whereas the original deficits are not affected significantly.

Distinctive phases and variability of vibration-induced postural reactions highlighted by center of pressure analysis

Distinctive phases and variability of vibration-induced postural reactions highlighted by center of pressure analysis

Vibration-induced postural reactions: A scoping review on parameters and populations studied

Vibration-induced postural reactions: A scoping review on parameters and populations studied

Evaluation Of Prognostic Factors and Tools for Prediction of Ambulation in Children with Cerebral Palsy: A Review

Cerebral Palsy is the leading cause for pediatric chronic disability and parents’ caregivers, neurologists and pediatric rehabilitation specialists would find it difficult to predict the prognosis of ambulation in children with cerebral palsy. The prediction of ambulation in children with cerebral palsy is of utmost importance still there is no definitive tool available to predict their ambulation. Gross motor skill achievements like age of achievement of neck holding as 9 months, sitting independently by the age of 2 years, crawling and all other milestones achievement by 30 months, along with postural reactions, infantile reflexes, cognitive, visual and hearing functions are proven to be the prognostic factors for prediction of ambulation. Even good upper extremity functions are positive prognostic factors for prediction of ambulation in cerebral palsy. Thai ambulation chart is also available which claims to guide the prognosis of ambulation in children with cerebral palsy. The reliability and validity of this tool is yet to be studied to use it as a prediction tool for ambulation in cerebral palsy. Further research is needed in this field to get an appropriate tool for prediction of ambulation in cerebral palsy which considers all the factors other than above mentioned factors.

Trunk postural reactions to the force perturbation intensity and frequency during sitting astride in children with cerebral palsy.

The purpose of this study was to examine kinematic and neuromuscular responses of the head and body to pelvis perturbations with different intensities and frequencies during sitting astride in children with CP. Sixteen children with spastic CP (mean age 7.4 ± 2.4years old) were recruited in this study. A custom designed cable-driven robotic horse was used to apply controlled force perturbations to the pelvis during sitting astride. Each participant was tested in four force intensity conditions (i.e., 10%, 15%, 20%, and 25% of body weight (BW), frequency = 1Hz), and six force frequency conditions (i.e., 0.5Hz, 1Hz, 1.5Hz, 2Hz, 2.5Hz, and 3Hz, intensity = 20% of BW). Each testing session lasted for one minute with a one-minute rest break inserted between two sessions. Kinematic data of the head, trunk, and legs were recorded using wearable sensors, and EMG signals of neck, trunk, and leg muscles were recorded. Children with CP showed direction-specific trunk and neck muscle activity in response to the pelvis perturbations during sitting astride. Greater EMG activities of trunk and neck muscles were observed for the greater intensities of force perturbations (P < .05). Participants also showed enhanced activation of antagonistic muscles rather than direction-specific trunk and neck muscle activities for the conditions of higher frequency perturbations (P < .05). Children with CP may modulate trunk and neck muscle activities in response to greater changes in intensity of pelvis perturbation during sitting astride. Perturbations with too high frequency may be less effective in inducing direction-specific trunk and neck muscle activities.

When mechanical engineering inspired from physiology improves postural-related somatosensory processes

Despite numerous studies uncovering the neural signature of tactile processing, tactile afferent inputs relating to the contact surface has not been studied so far. Foot tactile receptors being the first stimulated by the relative movement of the foot skin and the underneath moving support play an important role in the sensorimotor transformation giving rise to a postural reaction. A biomimetic surface, i.e., complying with the skin dermatoglyphs and tactile receptors characteristics should facilitate the cortical processes. Participants (n = 15) stood either on a biomimetic surface or on two control surfaces, when a sudden acceleration of the supporting surface was triggered (experiment 1). A larger intensity and shorter somatosensory response (i.e., SEP) was evoked by the biomimetic surface motion. This result and the associated decrease of theta activity (5–7 Hz) over the posterior parietal cortex suggest that increasing the amount of sensory input processing could make the balance task less challenging when standing on a biomimetic surface. This key point was confirmed by a second experiment (n = 21) where a cognitive task was added, hence decreasing the attentional resources devoted to the balance motor task. Greater efficiency of the postural reaction was observed while standing on the biomimetic than on the control surfaces.

Evaluation of postural stability under single and dual task conditions in individuals with and without intellectual disability

Background: The aim was to investigate how varying levels of intellectual disability (ID) impact postural stability parameters and response reaction time (RRT). Method: Fifty-nine individuals with low and moderate levels of ID and 55 sex- and age-matched peers without ID performed a bipedal standing postural control task while having their (I) eyes open [OE], (II) eyes closed [CE], and (III) while performing a secondary cognitive task- pressing a trigger button while maintaining still stance (dual task, DT). Seven postural control parameters (total, mediolateral and anteroposterior displacement, sway area, sway mean velocity, mediolateral dispersion, and anteroposterior dispersion) during each experimental condition as well as the RRT during the DT were recorded. Results: The results revealed that (I) CE and DT partially affected postural control parameters when compared to OE condition (in 13 and in 3 out of 21 pairwise comparisons, respectively), (II) individuals with ID had poorer postural control than peers without ID during the OE and DT conditions (p ≤ 0.05), but not during the CE condition (except for the larger total displacement observed in participants with moderate disability compared to participants without ID, p ≤ 0.05), (III) RRT was longer in individuals with ID compared to the group without ID (p ≤ 0.001), and (IV) no postural control parameter (p ≥ 0.05) nor RRT (p = 0.138) revealed differences between the participants with low and moderate levels of ID. Conclusions: These findings suggest that individuals with ID present reduced performance in the postural control parameters especially when they need to respond to DT compared to individuals without ID.