Effect of Sedation on the Neurological Examination of the Patellar and Withdrawal Reflexes in Healthy Dogs

Introduction: Pain, temperament, fear, and anxiety can prevent safe and accurate evaluation of common neurologic reflexes in dogs. When sedation is used it is unknown how the neurological examination, and specifically patellar and withdrawal reflexes are affected, and, if present, how long any effect might last. The purpose of this study is to investigate the effect of sedation on the evaluation of select common limb spinal reflexes in healthy dogs.Material and Methods: Fourteen healthy dogs with normal neurologic exams were included. After placing joint landmarks, patellar reflex and pelvic and thoracic limb withdrawal reflexes were tested. Joint angles were measured, obtaining reflex angle endpoints, change in angle, and change in time to reflex completion. These measurements were recorded at different time points: prior to sedation (awake timepoint), 15 and 30 min following administration of standardized sedation protocol of dexmedetomidine and butorphanol, and 15 and 30 min following administration of a standardized reversal agent, atipamazole.Results: For patellar reflex, the stifle end angle increased from 91.5 to 108.55 degrees (p < 0.0001) 15 min following sedation, and remained increased at 104.5 degrees (p < 0.0001) 30 min following sedation. Stifle change in angle increased from 9.6 to 24.4 degrees (p < 0.0001) 15 min following sedation, and remained increased at 20.85 degrees (p < 0.0001) and 11 degrees (p = 0.012) at 30 min sedation and 15 min reversal. Tarsal joint in pelvic withdrawal and elbow in thoracic withdrawal reflexes did not differ in at any timepoint of sedation or reversal when compared with the awake timepoint, for end angle or change in angle. The increases in end angle and change in angle for patellar reflex generated a change in time for patellar reflex from 0.12 s (awake) to 0.129 s (15 min sedation) which was statistically significant (p = 0.041). Change in time did not differ for pelvic withdrawal or thoracic withdrawal.Discussion/Conclusions: Reflexes were elicited in all dogs under sedation. Sedation does not affect the evaluation of the withdrawal reflex on any limb but improves the visualization of the patellar reflex in this group of neurologically normal dogs.

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Neurological examination in healthy chinchillas (Chinchilla lanigera)

Laboratory Animals ◽

10.1177/0023677217698000 ◽

2017 ◽

Vol 51 (6) ◽

pp. 629-635 ◽

Cited By ~ 2

Author(s):

Renata Snow ◽

Christoph Mans ◽

Helena Rylander

Keyword(s):

Neurological Examination ◽

Neurological Diseases ◽

Companion Animals ◽

Healthy Patient ◽

Functional Tests ◽

Clinically Normal ◽

Thoracic Limb ◽

Pelvic Limb ◽

Withdrawal Reflexes ◽

Laboratory Models

Chinchillas are popular as laboratory models and companion animals, and they can be affected by a variety of infectious and non-infectious neurological diseases. Little information is available on making a neurological diagnosis in this species, in part because the neurological examination has not been standardized in chinchillas and the expected physiological findings in healthy chinchillas have not been reported. In this study, a standardized neurological examination was performed on 30 clinically normal chinchillas. The perineal reflex and the menace response were absent in all chinchillas evaluated and so should not be used as functional tests. Several tests were consistently positive, such as the oculocephalic reflex, maxillary, mandibular and auricular sensations, withdrawal reflexes, thoracic limb paw replacement, and the wheelbarrow test. Other tests, such as the cutaneous trunci reflex and pelvic limb paw replacement, had variable responses. Based on these findings, it is advised that clinicians prioritize tests that can be easily performed without undue stress to the animal, and give consistent results in a healthy patient.

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Neurological examination of small ruminants

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.15005 ◽

2017 ◽

Vol 57 (1) ◽

pp. 11

Author(s):

N. D. GIADINIS (Ν. Δ. ΓΙΑΔΙΝΗΣ) ◽

N. K. PANOUSIS (Ν. Κ. ΠΑΝΟΥΣΗΣ) ◽

Z. POLIZOPOULOU (Ζ. ΠΟΛΥΖΟΠΟΥΛΟΥ) ◽

H. KARATZIAS (Χ. ΚΑΡΑΤΖΙΑΣ)

Keyword(s):

Neurological Examination ◽

Neurological Diseases ◽

Small Ruminants ◽

Spinal Reflexes ◽

Pain Sensation ◽

Postural Reactions ◽

Cranial Nerve Function ◽

Level Of Consciousness ◽

Neurological Problem ◽

Anatomical Localization

The neurological examination in small ruminants is very helpful in confirming the presence of a neurological problem and localizing the site of the lesion. The anatomical localization is useful for the differential diagnosis, prognosis and treatment of neurological diseases. A thorough review of the case history and clinical examination are followed by the inspection from a distance in order to assess behavior, level of consciousness and position of head, trunk and limbs. The locomotion disorders are evaluated upon walking the animals. Proprioception is examined with the postural reactions and cranial nerve function with the testing of the appropriate reflexes. The neurological examination is completed with the evaluation of muscular tone, spinal reflexes and the assessment of superficial and deep pain sensation.

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The nociceptive withdrawal reflex does not adapt to joint position change and short-term motor practice

F1000Research ◽

10.12688/f1000research.2-158.v2 ◽

2013 ◽

Vol 2 ◽

pp. 158 ◽

Cited By ~ 1

Author(s):

Nathan Eckert ◽

Zachary A Riley

Keyword(s):

Upper Limb ◽

Reflex Response ◽

Short Term ◽

General Direction ◽

Nociceptive Withdrawal Reflex ◽

Withdrawal Reflex ◽

Motor Practice ◽

Withdrawal Reflexes ◽

Sensory Encoding ◽

Withdrawal Response

The nociceptive withdrawal reflex is a protective mechanism to mediate interactions within a potentially dangerous environment. The reflex is formed by action-based sensory encoding during the early post-natal developmental period, and it is unknown if the protective motor function of the nociceptive withdrawal reflex in the human upper-limb is adaptable based on the configuration of the arm or if it can be modified by short-term practice of a similar or opposing motor action. In the present study, nociceptive withdrawal reflexes were evoked by a brief train of electrical stimuli applied to digit II, 1) in five different static arm positions and, 2) before and after motor practice that was opposite (EXT) or similar (FLEX) to the stereotyped withdrawal response, in 10 individuals. Withdrawal responses were quantified by the electromyography (EMG) reflex response in several upper limb muscles, and by the forces and moments recorded at the wrist. EMG onset latencies and response amplitudes were not significantly different across the arm positions or between the EXT and FLEX practice conditions, and the general direction of the withdrawal response was similar across arm positions. In addition, the force vectors were not different after practice in either the practice condition or between EXT and FLEX conditions. We conclude the withdrawal response is insensitive to changes in elbow or shoulder joint angles as well as remaining resistant to short-term adaptations from the practice of motor actions, resulting in a generalized limb withdrawal in each case. It is further hypothesized that the multisensory feedback is weighted differently in each arm position, but integrated to achieve a similar withdrawal response to safeguard against erroneous motor responses that could cause further harm. The results remain consistent with the concept that nociceptive withdrawal reflexes are shaped through long-term and not short-term action based sensory encoding.

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A comparison of stride parameters and carpal and tarsal joint angles during terrestrial and swimming locomotion in domestic dogs

Comparative Exercise Physiology ◽

10.3920/cep200076 ◽

2021 ◽

pp. 1-10

Author(s):

S. O’Rourke ◽

A.P. Wills

Keyword(s):

Range Of Motion ◽

Published Data ◽

Joint Angles ◽

Aquatic Locomotion ◽

Industry Practice ◽

Healthy Dogs ◽

Underwater Camera ◽

Stride Parameters ◽

Water Treadmill ◽

Swimming Kinematics

In recent years, canine hydrotherapy has become increasingly popular to treat a range of conditions despite a lack of empirical evidence. It is currently unclear whether joint angles and limb movements performed by dogs during swimming are quantifiably beneficial for healthy animals. This study investigated the swimming kinematics of healthy dogs to establish baseline data for this activity and compare limb kinematics to that of overground locomotion. Kinematic data were recorded from eight healthy dolichocephalic dogs (mean age: 3.4±2.2) of a variety of breeds. Overground data were collected prior to swimming and consisted of dogs trotting on a flat surface. Swimming data were collected using an underwater camera during a standard hydrotherapy session conducted by a trained canine hydrotherapist. Range of motion, primarily due to an increase in flexion, was significantly greater (P<0.005) during swimming than trotting. Stride length (P<0.001) and frequency (P<0.005) were both significantly reduced in swimming compared to trot. Swimming kinematics recorded in this study are consistent with previously published data on canine aquatic locomotion but differ from those previously reported for water treadmill exercise. This study provides an insight into aquatic locomotion in healthy dogs indicating that range of motion exceeds that of terrestrial gaits. It is unclear whether these changes are beneficial for healthy animals and therefore further research is required to develop evidence-based protocols for industry practice.

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Kinematic analysis of the thoracic limb of healthy dogs during descending stair and ramp exercises

American Journal of Veterinary Research ◽

10.2460/ajvr.79.1.33 ◽

2018 ◽

Vol 79 (1) ◽

pp. 33-41 ◽

Cited By ~ 1

Author(s):

Nadia L. Kopec ◽

Jane M. Williams ◽

Gillian F. Tabor

Keyword(s):

Kinematic Analysis ◽

Thoracic Limb ◽

Healthy Dogs

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Cerebellar Responses Evoked by Nociceptive Leg Withdrawal Reflex as Revealed by Event-Related fMRI

Journal of Neurophysiology ◽

10.1152/jn.00053.2003 ◽

2003 ◽

Vol 90 (3) ◽

pp. 1877-1886 ◽

Cited By ~ 29

Author(s):

A. Dimitrova ◽

F. P. Kolb ◽

H.-G. Elles ◽

M. Maschke ◽

M. Forsting ◽

...

Keyword(s):

Mossy Fiber ◽

Anterior Lobe ◽

Functional Brain Imaging ◽

Emg Activity ◽

Medial Malleolus ◽

Posterior Lobe ◽

Withdrawal Reflex ◽

Lateral Posterior ◽

Crus I ◽

Withdrawal Reflexes

The aim of the present study was to examine nociceptive leg withdrawal reflex–related areas in the human cerebellum using event-related functional brain imaging (fMRI). Knowledge about cerebellar areas involved in unconditioned limb withdrawal reflex control has some relevance in understanding data of limb withdrawal reflex conditioning studies. Sixteen healthy adult subjects participated. Nociceptive leg withdrawal reflexes were evoked by electrical stimulation of the left tibial nerve behind the medial malleolus. An event-related fMRI paradigm was applied with a total of 30 stimuli being delivered pseudorandomly during 500 consecutive MR scans. Surface electromyographic (EMG) recordings were performed from the left anterior tibial muscle. Only trials with significant reflex EMG activity were used as active events in fMRI statistical analysis. The specified contrasts compared the active event condition with rest. Leg withdrawal reflex–related areas were located within the vermis, paravermis, and lateral posterior cerebellar hemispheres bilaterally. Vermal and paravermal areas in lobules III/IV in the anterior lobe and in lobule VIII in the posterior lobe agree with the cerebellar representation of climbing and mossy fiber hindlimb afferents and voluntary leg movements. They are likely related to efferent modulation of the leg withdrawal reflex and/or sensory processing of afferent inputs from the reflex and/or the noxious stimulus. Additional activation within vermal lobule VI and hemispheral lobules VI/Crus I may be related to other pain-related processes (e.g., facial grimacing, fear, and startlelike reactions).

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Adaptability of the nociceptive withdrawal reflex

F1000Research ◽

10.12688/f1000research.2-158.v1 ◽

2013 ◽

Vol 2 ◽

pp. 158

Author(s):

Nathan Eckert ◽

Zachary A Riley

Keyword(s):

Upper Limb ◽

Reflex Response ◽

Protective Mechanism ◽

Short Term ◽

General Direction ◽

Nociceptive Withdrawal Reflex ◽

Withdrawal Reflex ◽

Withdrawal Reflexes ◽

Sensory Encoding ◽

Withdrawal Response

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Male Wistar rats show uniform wind-up responses in carrageenan-induced inflammation but not in the normal situation

Laboratory Animals ◽

10.1258/002367703766453056 ◽

2003 ◽

Vol 37 (3) ◽

pp. 207-214 ◽

Cited By ~ 3

Author(s):

R. Solano ◽

J. Mazario ◽

J. M. Orellana ◽

J. F. Herrero

Keyword(s):

Spinal Cord ◽

Wistar Rats ◽

Motor Units ◽

Spinal Reflexes ◽

Modular Organization ◽

Saturation Point ◽

Single Motor Units ◽

Male Wistar Rats ◽

C Fibre ◽

Withdrawal Reflexes

The technique of recording spinal cord withdrawal reflexes as single motor units (SMUs) does not require intense preparatory surgery and allows the study of the nociceptive system in physiological conditions. It has been used to show that the wind-up phenomenon depends on the level of excitability of spinal cord neurones, the integrity of the spinal cord and the parameters of the stimulation used. We have now used SMU recordings to assess whether wind-up is also an heterogeneous phenomenon depending on the muscle studied, and, if so, how the presence of hyperalgesia affects its generation. The experiments were performed in normal and carrageenan-induced inflammation in male Wistar rats anesthetized with α-chloralose. Wind-up was recorded in units from peroneus longus, tibialis anterior and extensor digitorum longus. The results showed that in normal animals, the curves of C-fibre mediated wind-up reached saturation at different times and the shape of the curves was different depending on the muscle studied and on the intensity of stimulation used. In inflammation, however, C-fibre mediated wind-up became very uniform in the muscles studied, with a similar shape and saturation point. A-fibre mediated wind-up was only observed in animals with inflammation and no differences were observed between muscles. We conclude that in the absence of preparatory surgery and inflammation, C-fibre wind-up is heterogeneous, and supports a modular organization of nociceptive spinal reflexes. In hyperalgesia, however, wind-up curves are similar in units from different muscles, confirming a loss of modular organization that also affects the generation of wind-up.

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Modulation of an inhibitory interneuron in the neural circuitry for the tail withdrawal reflex of Aplysia

Journal of Neurophysiology ◽

10.1152/jn.1995.73.3.1313 ◽

1995 ◽

Vol 73 (3) ◽

pp. 1313-1318 ◽

Cited By ~ 3

Author(s):

Y. Xu ◽

J. P. Pieroni ◽

L. J. Cleary ◽

J. H. Byrne

Keyword(s):

Spontaneous Activity ◽

Motor Neurons ◽

Inhibitory Interneuron ◽

Resting Membrane Potential ◽

Differential Modulation ◽

Inhibitory Effects ◽

Withdrawal Reflex ◽

Inhibitory Postsynaptic Potentials ◽

Bath Application ◽

Withdrawal Reflexes

1. Serotonin (5-HT), small cardioactive peptide B (SCPB) and FMRFamide have well-established facilitatory and inhibitory effects on sensory neurons and their connections with motor neurons mediating withdrawal reflexes in Aplysia. Little is known, however, about their effects on interneurons contributing to those reflexes. As a first step, we examined the effects of these three transmitters on the identified inhibitory interneuron RP14 in isolated pleural-pedal ganglia. 2. Bath application of 5-HT hyperpolarized RP14, inhibited its spontaneous activity and decreased its excitability. In addition, 5-HT decreased the amplitude of inhibitory postsynaptic potentials produced by RP14 in tail sensory and motor neurons. 3. In contrast, bath application of SCPB increased spontaneous activity in RP14. Subsequent application of 5-HT to the bath, which still contained SCPB, inhibited RP14. Therefore, the effects of SCPB were essentially opposite to those of 5-HT on this inhibitory interneuron. 4. FMRFamide had little effect on RP14. It did not produce an obvious change in its resting membrane potential and produced only a transient increase in its spontaneous activity. 5. These results suggest that various neuromodulators have differential effects on elements of the neuronal circuit underlying the tail-withdrawal reflex of Aplysia. Differential modulation may determine the overall behavioral manifestations associated with sensitization.

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Goniometric Evaluation and Passive Range of Joint Motion in Chondrodystrophic and Non-Chondrodystrophic Dogs of Different Sizes

VCOT Open ◽

10.1055/s-0040-1713825 ◽

2020 ◽

Vol 03 (02) ◽

pp. e66-e71

Author(s):

Mhayara Reusing ◽

Mayara Brocardo ◽

Saulo Weber ◽

José Villanova

Keyword(s):

Medium Size ◽

Joint Motion ◽

Joint Angles ◽

Size Groups ◽

Bonferroni Test ◽

Healthy Dogs ◽

Student’S T ◽

Levene Test ◽

Flexion And Extension ◽

Student’S T Test

Abstract Objective This study aimed to evaluate angle values in maximal flexion and extension; the passive range of motion (PROM) of the shoulder, elbow, carpal, hip, stifle and tarsus; and the carpal abduction and adduction of chondrodystrophic (CD) and non-chondrodystrophic (NCD) dogs of different sizes. Study Design Goniometric evaluation was performed in triplicate using a universal goniometer. CD dogs were categorized into miniature, small, medium, large and giant sizes, whereas NCD dogs were allocated to small- and medium-size groups. Hence, each of the seven subgroups comprised 11 clinically healthy dogs. For data analysis, the Levene test was used to evaluate homoscedasticity. The means of each joint angle with the means in each group as well as the PROM between the CD and NCD groups was compared by the Student's t-test; meanwhile, the means of the joint angles and ROM among the sizes were compared by analysis of variance, followed by the Tukey test. In those cases, when no homogeneity variance was observed, the Bonferroni test was used. In every case, p ≤ 0.05 was considered significant. Results The articular angles and PROM differed according to the dog size and type, that is, CD or NCD. Conclusion The goniometric values and PROM of dogs depend on the joint type, dog size and chondrodystrophy status. Further studies are necessary to increase the accuracy of the results and to establish the predominant factors governing the differences discovered.

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