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1.
Normal values for motor conduction in the tibial, ulnar and fibular nerves of dogs have been determined using a new method for recording and analysing evoked motor potentials. The use of an alligator clip as a roving surface electrode for recording, and a personal computer to analyse the evoked potentials has facilitated faster and more reproducible motor conduction studies. Compound muscle action potential (CMAP) and motor nerve conduction velocity data are in good agreement with previous studies. Normal values for CMAP area, residual latency and proximal to distal ratios for CMAP area and amplitude are presented for the first time.  相似文献   

2.
Motor nerve conduction parameters in the cat   总被引：1，自引：0，他引：1  
The electrophysiological characteristics of motor conduction in normal cats have been determined using an alligator clip as a surface electrode to record the compound muscle action potential (CMAP) following stimulation of the tibial, ulnar and fibular nerves. Data on nerve conduction velocity, residual latency and the amplitude and area of the CMAP have been determined using a computerised electromyography unit. Motor nerve conduction was substantially faster in cats than dogs and the site of stimulation had less effect on the size and area of the CMAP. Although a small decline in the amplitude of successive CMAPs was observed following repetitive stimulation of the tibial and ulnar nerve at 20 Hz, the decrement was less marked than in the dog.  相似文献   

3.
A 5-month-old female Border Collie was evaluated because of progressive hind limb ataxia. The predominant clinical findings suggested a sensory neuropathy. Sensory nerve conduction velocity was absent in the tibial, common peroneal, and radial nerves and was decreased in the ulnar nerve; motor nerve conduction velocity was decreased in the tibial, common peroneal, and ulnar nerves. Histologic examination of nerve biopsy specimens revealed considerable nerve fiber depletion; some tissue sections had myelin ovoids, foamy macrophages, and axonal degeneration in remaining fibers. Marked depletion of most myelinated fibers within the peroneal nerve (a mixed sensory and motor nerve) supported the electrodiagnostic findings indicative of sensorimotor neuropathy. Progressive deterioration in motor function occurred over the following 19 months until the dog was euthanatized. A hereditary link was not established, but a littermate was similarly affected. The hereditary characteristic of this disease requires further investigation.  相似文献   

4.
Background: Hypothyroidism has been implicated in the development of multiple peripheral mono‐ and polyneuropathies in dogs. The objectives of this study were to evaluate the clinical and electrophysiologic effects of experimentally induced hypothyroidism on the peripheral nervous system of dogs. Hypothesis: Chronic hypothyroidism will induce peripheral nerve sensorimotor dysfunction. Animals: Eighteen purpose‐bred, female dogs. Methods: Prospective, longitudinal study: Hypothyroidism was induced by radioactive iodine administration in 9 dogs, and the remaining 9 served as untreated controls. Neurological examinations were performed monthly. Electrophysiologic testing consisting of electromyography (EMG); motor nerve conduction studies of the sciatic‐tibial, radial, ulnar, and recurrent laryngeal nerves; sciatic‐tibial and ulnar F‐wave studies; sensory nerve conduction studies of the tibial, ulnar, and radial nerves; and evaluation of blink reflex and facial responses were performed before and 6, 12, and 18 months after induction of hypothyroidism and compared with controls. Results: Clinical evidence of peripheral nervous dysfunction did not occur in any dog. At 6 month and subsequent evaluations, all hypothyroid dogs had EMG and histologic evidence of hypothyroid myopathy. Hypothyroid dogs had significant (P≤ .04) decreases in ulnar and sciatic‐tibial compound muscle action potentials over time, which were attributed to the concurrent myopathy. No significant differences between control and hypothyroid dogs were detected in electrophysiologic tests of motor (P≥ .1) or sensory nerve conduction velocity (P≥ .24) or nerve roots (P≥ .16) throughout the study period, with values remaining within reference ranges in all dogs. Conclusion: Chronic hypothyroidism induced by thyroid irradiation does not result in clinical or electrophysiologic evidence of peripheral neuropathy, but does cause subclinical myopathy.  相似文献   

5.
OBJECTIVE: To establish reference values for electrodiagnostic evaluation of peripheral nerve function in birds. ANIMALS: 6 rheas and 6 barred owls. PROCEDURE: Birds were anesthetized with propofol or isoflurane in oxygen. Using a computer-based electromyograph system and needle electrodes for stimulation and recording, electromyography (EMG) was performed on the pectoral, biceps brachialis, and gastrocnemius muscles, and evoked EMG was performed on the tibial and ulnar nerves. Motor nerve conduction velocity (MNCV) was calculated. Repetitive stimulation was performed on these 2 nerves. Late F waves were recorded for each nerve, when possible. RESULTS: Activity was evident during insertion of the electrodes, but muscles tested were electrically quiescent after spontaneous EMG. Motor nerve conduction velocity was faster in the tibial nerve than ulnar nerve but did not differ significantly between species. Mean +/- SEM MNCV was 132.3+/-7.8 m/s for the tibial nerve and 59.7+/-7.8 m/s for the ulnar nerve. A significant difference was not observed in responses at the fourth or ninth stimulation during repetitive stimulation. Subsequent to the initial stimulation, amplitudes were +/-22.7% of the initial motor potential amplitude. Recorded F waves were inconsistent, which may have been associated with technique. CONCLUSIONS AND CLINICAL RELEVANCE: Reference range (mean +/-2 SEM) for MNCV was 34.1 to 75.3 m/s for the ulnar nerve and 116.7 to 147.9 m/s for the tibial nerve in barred owls and rheas. After repetitive stimulation, motor potential amplitudes may be +/-22.7% of the initial amplitude response.  相似文献   

6.
Supramaximal percutaneous nerve stimulation was used in motor nerve conduction velocity studies conducted in ten middle-aged, clinically normal dogs. Dogs were separated into two groups; dogs in one group weighted less than or equal to 7.5 kg and dogs in the other group weighted greater than or equal to 15.9 kg. Mean values and SEM were recorded for radial (72.1 +/- 1.9 m/s), median 65.6 +/- 2.1 m/s), ulnar (58.9 +/- 1.0 m/s), tibial (68.2 +/- 1.4 m/s), and peroneal (79.8 +/- 1.8 m/s) nerves. Values for latency, amplitude, and duration for proximal and distal evoked potentials were recorded. Analysis of mean nerve conduction velocity values for all nerves between the two groups indicated no statistical difference (P greater than 0.05). However, the two groups were statistically different (P less than 0.05) when values for distal latency and measurements of nerve length were compared. These data suggest that if latency is substituted for velocity measurements, various populations of dogs must be considered to clarify interpretation.  相似文献   

7.
A study of the ultrasonographic appearance and size of the sciatic, tibial, peroneal, suprascapular, radial, median, and ulnar nerves and a comparison with the anatomic size and location of these nerves in the normal adult horse is reported. Cadavers and live horses were studied. Landmarks for localization and techniques for nerve identification are described. The depth and diameter of each nerve at various locations and the success rate in imaging each nerve are reported. Statistically significant correlations were found between anatomically and ultrasonographically measured nerve depths and diameters. The success rate in identifying nerves was 70% in the live horses and 49% in cadavers, with the deep peroneal nerve being the easiest to identify. Some applications of this technique in horses are discussed.  相似文献   

8.
A technique for measuring motor nerve conduction velocities (NCV) in sheep was developed using 15 clinically normal ewes. Mean ±SD values were determined for the radial (76.3±12.5 m/s), peroneal (103.9±12.7 m/s), and tibial (98.6±13.1 m/s) nerves. The recording needle electrode was located in the extensor carpi radialis, tibialis cranialis, and gastrocnemius muscles, respectively. Latencies, amplitudes and durations of the proximal and distal evoked compound muscle action potentials are given. To investigate further the unexpectedly high NCVs calculated for the peroneal and tibial nerves, analogous stimulating and recording electrode sites were used in 7 clinically normal dogs. The corresponding canine peroneal (88.1±8.3 m/s) and tibial (89.2±12.4 m/s) NCVs were higher than the standard sciatic-tibial NCV recorded from the interosseous Myelinated nerve fiber diameters were measured on semithin transverse sections of peroneal and tibial nerve specimens taken from a clinically normal ewe and bitch. A possible explanation for the relative species difference in the proximal peroneal and tibial NCV values is the presence of fibers in both the peroneal and tibial nerves of the sheep which were as much as 3 wider than the largest fibers found in the dog.  相似文献   

9.
Electrophysiologic investigations of motor and sensory nerve as well as ventral nerve root function were performed on 12 dogs with suspected acute canine polyradiculoneuropathy (ACP) at different stages and with different severity of disease. The most reliable electrophysiologic indicators of ACP were electromyographic changes (occurring in 100% of affected dogs), significantly decreased compound muscle action potential amplitudes (in 75, 90, and 100% of affected dogs at all sites along the sciatic/tibial, radial, and ulnar nerves, respectively), increased minimum F-wave latencies (67%), increased F ratios (92%), and decreased F-wave amplitudes (67%). These findings suggest that ACP represents a peripheral motor axonopathy, with demyelination and axonal involvement also occurring in ventral nerve roots. Evidence of peripheral demyelination was present in some dogs although it was overshadowed by the prominent axonopathy. ACP more closely resembles the acute axonal or intermediate forms of Guillain-Barré syndrome in people.  相似文献   

10.
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11.
OBJECTIVE: To establish normal predictive values for cord dorsum potential (CDP) onset latency after thoracic and pelvic limb sensory or mixed nerve stimulation in adult dogs. ANIMALS: 26 clinically normal adult dogs. PROCEDURE: Sensory nerve action potentials (SNAP) were recorded proximally from tibial and lateral superficial radial nerves after distal stimulation. The CDP were recorded from the L4-L5 interarcuate ligament for the tibial nerve and from the C7-T1 interarcuate ligament for the radial nerve. Linear regression analyses were performed for CDP onset latency, and mean +/- SD was calculated for CDP onset to peak latency differences and sensory nerve conduction velocities (SNCV). RESULTS: For the tibial nerve, expected CDP onset latency (CDPOL) = -1.194 + 0.014 X pelvic limb length (mm; R2 = 0.912); CDPOL = -2.156 + 0.011 X pelvic limb/spinal length (mm; R2 = 0.911); and CDPOL = 0.941 + 2.197 X tibial nerve SNAP latency (milliseconds; R2 = 0.903). For the radial nerve, CDPOL = -0.9 + 0.014 x thoracic limb length (mm; R2 = 0.873); and CDPOL = 1.454 + 1.874 X radial nerve SNAP latency (milliseconds; R2 = 0.903). Mean +/- SD for CDP onset to peak latency difference for tibial and radial nerves was 3.1+/-0.3 and 3.0+/-0.4 milliseconds, respectively. CONCLUSIONS: Strong linear associations exist between CDPOL and a number of easily measured peripheral independent variables in dogs. There is also a narrow range of normal values for CDP onset to peak latency differences that is independent of limb length. CLINICAL RELEVANCE: CDP evaluation can be used to accurately assess functional severity and distribution of abnormalities in proximal sensory nerves, dorsal nerve roots, and spinal cord dorsal horns in dogs with suspected neuropathy, radiculopathy, or myelopathy involving the brachial or lumbosacral intumescences.  相似文献   

12.
Sensory nerve conduction velocities in the cutaneous afferents of the ulnar and peroneal nerves of the neurologically normal adult dog were determined by stimulation at stimulus intensities of 15, 20 and 25 V through subcutaneously placed electrodes and by the averaged evoked response technique. Stimulus intensities of 15 V for the ulnar nerve and 20 V for the peroneal nerve were adequate to measure the sensory nerve conduction velocities of these nerves. A linear relationship was seen between sensory nerve conduction velocity (y in m/s) and tissue temperature (x in °C) and the regression equations were expressed as follows: y=1.6x+12.3 at a stimulus intensity of 15 V for the ulnar nerve and y=2.0x–10.6 at 20 V for the peroneal nerve, respectively. The 95% confidence limits of the regressions of the sensory nerve conduction velocities against tissue temperature, obtained at a stimulus intensity of 15 V for the ulnar nerve or at a stimulus intensity of 20 V for the peroneal nerve, were proposed for a tissue temperature-dependent reference range to enable the clinician to evaluate graphically the sensory nerve conduction velocity in a diseased dog.  相似文献   

13.
This study has been carried out to determine the effect of neutral position, hyperextension and hyperflexion of the tarsal joint on the tibial nerve, motor action potential latency and tarsal canal compartment pressure in dogs with the aid of electrophysiological and anatomical methods. Totally twenty healthy mongrel dogs were used. Latency of motor nerve action potential (MNAPL) studies of tibial nerve via surface stimulating and needle recording electrodes was performed on right hind limbs of all the dogs. The compartment pressures of the tarsal canal with the pressure transducer were determined from both limbs from ten of the dogs. In one dog, tarsal regions of both left and right limbs were demonstrated using magnetic resonance imaging (MRI). Two dogs were euthanatized and tarsal regions of the dogs were sectioned for correlative anatomy. Nerve conduction studies showed that the MNAP latency of the tibial nerve were 3.55 +/- 0.097 ms, 3.76 +/- 0.087 ms and 3.39 +/- 0.097 ms in neutral, hyperextension and hyperflexion positions, respectively. Hyperflexion of the tarsal joint caused prolongation of the MNAP latency of the tibial nerve with the highest pressure value being determined in tarsal canal. From the anatomical viewpoint, the distance between the flexor hallucis longus muscle and the superficial digital muscle was the shortest during hyperflexion and the plantar branch of saphenous artery, lateral and medial plantar nerves located more laterally in cadaver and MR imaging sections. As a result of this study, it is thought that tarsal region diseases as well as long time splint in the hyperflexion position as applied in the Ehmer sling can affect the compartment pressure and nerve tension because of occupying in the tarsal canal. Raising pressure and nerve stretching in the tarsal canal compartment could cause deficiencies in the conduction velocity of the tibial nerve. This might be a result of tarsal tunnel syndrome in the dog. Clinicians could consider this syndrome in cases of tarsal region diseases as well as application of long time splint in hyperflexion of tarsal joints in dogs.  相似文献   

14.
The motor cortex was transcranially and peripheral nervous structures (motor roots, plexus, peripheral nerves) were percutaneously stimulated by magnetic pulses in awake dogs and in dogs awaking from general anesthesia. The compound muscle action potentials were recorded by surface or needle electrodes. The central motor conduction time as an information about central motor tracts was obtained by subtracting the peripheral latency from the corticomuscular latency. The peripheral latency was assessed by high voltage electrical and magnetic stimulation of motor roots and by the F-wave technique. The motor conduction velocity of the tibial nerve was measured by percutaneous magnetic and by electrical stimulation and the resulting values were compared.  相似文献   

15.
Normal nerve conduction velocity values in 10 ponies were determined for sensory nerve fibers in the median and ulnar nerves. A percutaneous signal-averaging technique was developed and used. Medial and lateral palmar digital nerves on the abaxial surface of the proximal sesamoid bones were used as the sites for percutaneous stimulation, whereas recording sites included the medial and lateral palmar nerves just distal to the carpus and the median and ulnar nerves in the middle of the radius. Sensory nerve conduction velocities can be evaluated simply and clinically in the limbs of horses, using percutaneous signal-averaging techniques.  相似文献   

16.
Electromyographic examinations were performed at various times over a 40 week period in four mature dogs receiving chronic oral low doses of lead acetate and a control dog receiving sodium acetate. Blood lead levels in the four dogs were elevated (mean values 1.15, 2.18, 1.13 and 1.72 mumol/liter). No clinical signs of lead intoxication were present. Two dogs had evidence of a nonregenerative anemia. Neither needle electromyographic nor nerve conduction velocity studies showed evidence of a polyneuropathy. Teased nerve fiber preparations of proximal and distal segments of the ulnar and tibial nerves and muscle biopsies of distal appendicular muscles were normal in all dogs. Light microscopic examination of the brain, kidneys and liver revealed no abnormalities in the two dogs necropsied. In conclusion, a polyneuropathy was not produced experimentally in dogs ingesting low doses of inorganic lead for up to 40 weeks.  相似文献   

17.
Electrophysiological evaluation of traumatic forelimb paralysis of the dog   总被引：1，自引：0，他引：1  
The results of clinical neurological, electromyographic and electroneurographic examinations in 26 dogs with traumatic forelimb paralysis are presented. The results of neurological examination varied considerably among the cases. Electromyographic evidence of denervation in the epaxial muscles was observed in 22 dogs. A post ganglionic dorsal root lesion was diagnosed in 14 cases by the presence of an evoked sensory nerve action potential in association with loss of conscious pain perception in the appropriate area. Motor nerve studies in the ulnar nerve were not helpful in discriminating root lesions from spinal nerve involvement. It was concluded that electromyographic examination of the ipsilateral epaxial muscles under general anaesthesia is essential for the detection of root involvement. Sensory conduction studies in the radial nerve are indicated if conscious pain perception is absent in the fifth digit. Motor and sensory conduction studies of the ulnar nerve system seldom provide additional diagnostic information seldom provide additional diagnostic information. The absence of electrophysiological signs of root involvement does not exclude a post ganglionic dorsal root lesion.  相似文献   

18.
Methods of estimating motor nerve conduction, sensory nerve conduction, and f-wave latency in pigs were determined. The sciatic-tibial nerves were used for motor nerve conduction and f-wave response and the superficial peroneal nerve was used for sensory nerve conduction.  相似文献   

19.

Objective

To evaluate an ultrasound-guided technique for adductor canal (AC) block by describing the distribution of methylene blue around the AC, popliteal fossa, saphenous, tibial and common fibular nerves in dog cadavers.

Study design

Prospective experimental trial.

Animals

Ten mixed breed canine cadavers weighing 28.55 ± 3.94 kg.

Methods

Ultrasound scans of the AC were performed bilaterally in 10 canine cadavers. A high-frequency linear transducer was placed on the long axis of the pectineus muscle and using an in-plane technique, an insulated needle was introduced at a proximal to distal direction into the AC. Methylene blue 0.1% (0.3 mL kg?1) was administered followed by dissection. The presence of dye over the target nerves for ≥2 cm was considered successful distribution. Three of 10 cadavers were submitted to computed tomography (CT) and one of them to magnetic resonance (MR) evaluation.

Results

Methylene blue reached the AC in 20 (100%) and the popliteal fossa in 17 (85%) pelvic limbs. Staining was successful in the saphenous nerve (4.0 ± 1.57 cm) in 11 (55%) limbs, tibial nerve (2.65 ± 0.8 cm) in six (30%) and common fibular nerve (2.7 ± 0.9 cm) in four (20%). There was no evidence of staining around the motor branches of the femoral nerve. No intraneural or intravascular dye spread was found during dissections. Contrast distribution to the popliteal fossa was observed in three limbs (50%) in CT and in one (50%) MR image.

Conclusions and clinical relevance

Although the tibial and common fibular nerves were not stained as often as the saphenous nerve, dye was encountered throughout the popliteal fossa near the nerves. The AC block may be useful for intra and postoperative analgesia in stifle surgery with minimal femoral motor dysfunction. However, further study is required to confirm its efficacy and safety in vivo.  相似文献   

20.
The peripheral nerve of the hen has become an increasingly important animal model in studies of peripheral neuropathy, especially that induced by organophosphorus agent exposure. However, few electrophysiologic studies have been performed, and few data on normal peripheral nerve function exist. The purpose in the present study was to measure the characteristics of the compound action potential of peripheral nerves of the healthy hen. The results showed that conduction velocities of the tibial and the sciatic nerves were 41 m/s and 60 m/s, respectively. The relative refractory period was slightly shorter in the sciatic nerve. The tibial nerve exhibited a lower threshold for stimulation and a significantly shorter chronaxie (19 microseconds) than did the sciatic nerve (25 microseconds). Variability between animals was relatively small. These data should provide useful reference points on studies in which peripheral neuropathy is induced or suspected.  相似文献   

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