Use of aerobic treadmill exercises on nerve regeneration after sciatic nerve injury in spontaneously hypertensive rats

Purpose: Various postoperative protocols have been proposed to improve outcomes and accelerate nerve regeneration. Recently, the use of physical exercise in a post-surgical neurorraphy procedure has shown good results when started early. We experimentally investigated the hypothesis that post-operative exercise speeds up results and improves clinical and morphologic parameters. Methods: Isogenic rats were randomly divided into four groups: 1 SHAM; 2 SHAM submitted to the exercise protocol (EP); 3 Grafting of the sciatic nerve; and 4 Grafting of the sciatic nerve associated with the EP. The EP was based on aerobic activities with a treadmill, with a progressive increase in time and intensity during 6 weeks. The results were evaluated by the sciatic functional index (SFI), morphometric and morphologic analysis of nerve distal to the lesion, and the number of spinal cord motor neurons, positive to the marker Fluoro-Gold (FG), captured retrogradely through neurorraphy. Results: Functional analysis (SFI) did not show a statistical difference between the group grafted with (­50.94) and without exercise (-65.79) after 90 days. The motoneurons count (Spinal cord histology) also showed no diference between these groups (834.5 × 833 respectively). Although functionally there is no difference between these groups, morphometric study showed a greater density (53.62) and larger fibers (7.762) in GRAFT group. When comparing both operated groups with both SHAM groups, all values were much lower. Conclusions: The experimental model that this aerobic treadmill exercises protocol did not modify nerve regeneration after sciatic nerve injury and repair with nerve graft.

Tibial plateau leveling osteotomy in dogs: an ex vivo comparative study of knee's surrounding structures protection methods

Background: Cranial cruciate ligament failure is one of the leading causes of pelvic limb lameness in dogs and one of the most recommended treatments is tibial plateau leveling osteotomy (TPLO) surgery. However, this procedure may lead to some complications as fractures of the fibula, laceration in varying degrees of the popliteal vasculature and its branches, neuropraxia, neurotmeses, among others. The goals of this study were to compare the effectiveness of 8 methods used during TPLO, to prevent damage to the cranial tibial artery, fibula, tibial and fibular nerve (surgical compresses, specific surgical retractors I and II and an osteotomy technique variation). Materials, Methods & Results: A total of 40 canine cadavers weighing 25.9 ± 3.7 kg were submitted to TPLO. Animals were previously prepared with 1: 4 barium red latex solution, to provide radiopacity of arteries surrounding the knee (n = 80). TPLO was performed using 8 methods to protect the cranial tibial artery, fibula, and tibial and fibular nerves. Each method was used in one of the knees of 5 animals. The contralateral knee was maintained as a control (without protection). The knees were radiographed in orthogonal projections before and after the osteotomies and then anatomically dissected. The evaluated structures were photographed, and the images sent to four blind evaluators (visual macroscopy) to classify the possible injuries. The highest incidence of injuries was identified when protection methods were used. However, this difference was not significant (P > 0.05). No significant differences regarding efficacy were found between all 8 protection methods. Discussion: In this study, the total incidence of injuries following TPLO was 20% was much higher than that presented in the literature which indicates when considering only intraoperative injuries. The dogs cadavers tissue resistance and stiffened latex may have predisposed the osteotomy injury, as soft tissues with greater flexibility are less susceptible to trauma caused by the oscillatory saw. When compared to others cadaveric studies that also evaluated the efficacy of surgical dressings to protect the cranial tibial artery, during TPLO, we also find a higher incidence of damage. Maybe the limb's position was responsible for this difference, once in the after mentioned researches the limb was positioned suspended to simulate a dorsal decubitus position and we choose the limb position with the lateral face resting on the surface of the operating table, and this may have provided extra pressure from the structures towards the osteotomy saw, increasing the occurrence of those damages. Although the present study did not reveal a significant difference for the use of protection methods, we believe that the dimensions of the compresses used herein may have contributed to a higher incidence of injuries. They probably increased the tissue trauma needed for their allocation and led to a lower positioning accuracy for the isolation of these structures. Maybe for the same reason, the specific type II surgical retractor was the only shield that, observationally, did not increase the occurrence of injuries, once less dissection was required to allocate it. The difference in geometric dimensions between the retractors may justify the superiority of the retractor II, since it allows a more careful and apparently less traumatic allocation. Performing TPLO without adopting these protection methods did not lead to a higher risk of injury to the cranial tibial artery, fibula, and tibial and fibular nerves.

Study on the mechanisms of Suaeda rigida polysaccharides on the heart inhibition and skeletal muscle promotion in the frog / [Estudo sobre os mecanismos dos polissacarídeos de Suaeda rigida na inibição do coração e promoção da musculatura esquelética no sapo]

The objectives of this study were to investigate the effects of different concentrations of Suaeda rigida polysaccharides (SRPs) on the physiological characteristics of the frog heart and gastrocnemius muscle, compare their similarities and differences, and analyze the mechanisms. CaCl2 and acetylcholine (Ach) were selected respectively to be co-incubated with the high concentration SRPs to observe the effects on the heart contraction of frog. The effects of different concentrations of the SRPs on the activities of acetylcholinesterase (A-CHE), Na+-K+-ATPase and Ca2+-Mg2+-ATPase in the isolated frog heart were detected by UV-Vis spectrophotometry. The gastrocnemius muscle was immersed in the high concentration of SRPs for 10 min, and the systolic indexes were recorded. The effects of SRPs on the Ach content and A-CHE activity at the sciatic nerve-gastrocnemius junction were determined by UV-Vis spectrophotometry and enzyme-linked immunosorbent assay (ELISA). The results showed that the SRPs had significant inhibitory effects on the contractile amplitude of isolated heart and the contractile amplitude induced by CaCl2 and Ach, respectively (P<0.01). The activity of Ca2+-Mg2+-ATPase was significantly promoted, and the activity of A-CHE was significantly inhibited (P<0.01). The contraction amplitude, contraction rate, relaxation rate of gastrocnemius muscle and the Ach content at the junction of sciatic nerve-gastrocnemius muscle were significantly increased (P<0.01), and the activity of A-CHE at the junction was significantly inhibited (P<0.01) by the SRPs. All the results suggested that the SRPs could inhibit the contraction of heart and promote the contraction and relaxation of skeletal muscle. The mechanism was related to blocking the fast INa channel, inhibiting the ICa-L and activating the M receptors of myocardial membrane and then inhibiting external Ca2+ influx, increasing Ca2+-Mg2+-ATPase activity, decreasing a-che activity.

Os objetivos deste estudo foram investigar os efeitos de diferentes concentrações de Suaeda rigida polissacarídeos (SRPs) sobre as características fisiológicas do coração de rã e do músculo gastrocnêmio, comparar suas semelhanças e diferenças, e analisar os mecanismos. CaCl2 e acetilcolina (Ach) foram selecionados respectivamente para serem co-incubados com os SRPs de alta concentração para observar os efeitos sobre a contração do coração de rã. Os efeitos das diferentes concentrações dos SRPs sobre as atividades da acetilcolinesterase (A-CHE), Na+-K+-ATPase e Ca2+-Mg2+-ATPase no coração isolado de rã foram detectados pela espectrofotometria UV-Vis. O músculo gastrocnêmio foi imerso na alta concentração de SRP por 10 min, e os índices sistólicos foram registrados. Os efeitos das SRPs no conteúdo de Ach e na atividade de A-CHE na junção nervo-gastrocnêmio ciático foram determinados pela espectrofotometria UV-Vis e pelo ensaio de imunoabsorção enzimática (ELISA). Os resultados mostraram que os SRPs tiveram efeitos inibidores significativos sobre a amplitude contrátil do coração isolado e a amplitude contrátil induzida por CaCl2 e Ach, respectivamente (P<0,01). A atividade do Ca2+-Mg2+-ATPase foi significativamente promovida e a atividade do A-CHE foi significativamente inibida (P<0,01). A amplitude de contração, a taxa de contração, a taxa de relaxamento do músculo gastrocnêmio e o conteúdo de Ach na junção do músculo nervo ciático-gastrocnêmio foram significativamente aumentados (P<0,01), e a atividade do A-CHE na junção foi significativamente inibida (P<0,01) pelas SRPs. Todos os resultados sugeriram que os SRPs poderiam inibir a contração do coração e promover a contração e o relaxamento do músculo esquelético. O mecanismo estava relacionado ao bloqueio do canal INa rápido, inibindo a ICa-L e ativando os receptores M da membrana miocárdica e depois inibindo o influxo externo de Ca2+, aumentando a atividade de Ca2+-Mg2+-ATPase, diminuindo a atividade a-che.

Stem cells in end-to-side neurorrhaphy: experimental study in rats

Purpose: To evaluate the influence of mesenchymal stem cells from adipose tissue in the end-to-side neurorrhaphy, focusing in the nerve regeneration and the muscle reinnervation in acute trauma. Methods: 140 animals were randomly divided in seven groups: control, denervated, end-to-side neurorrhaphy between distal stump of common peroneal nerve and tibial nerve (ESN), ESN wrapped in fascia, ESN wrapped in fascia and platelet gel, ESN wrapped in platelet gel, ESN wrapped in fascia and platelet gel within stem cells (without culture) removed from the adipose tissue. Mass measurements of the animal and of cranial tibial muscles, electromyography, walking track analysis tests and histological examinations of the nerves and muscles after 180 days was performed. Results: In the groups where the ESN was performed, the results were always better when compared to the denervated group, showing reinnervation in all ESN groups. The most sensitive methods were walking track and histological analysis. Only the group with stem cells showed values similar to the control group, as well as the functional indices of peroneal nerve and the number of nerve fibers in the peroneal nerve. Conclusions: Stem cells were effective in ESN according with the functional index of the peroneal nerve, evaluated by walking track analysis and the number of nerve fibers in the peroneal nerve.(AU)

Criteria for assessing peripheral nerve injury: behavioral and functional assessment in non-operated Wistar rats

Purpose To evaluate the normality pattern in functional tests of peripheral nerves. Methods Sixty female and sixty male Wistar rats were submitted to vibrissae movement and nictitating reflex for facial nerve; grooming test and grasping test for brachial plexus; and walking tracking test and horizontal ladder test for lumbar plexus. The tests were performed separately, with an interval of seven days between each. Results All animals showed the best score in vibrissae movement, nictitating reflex, grooming test, and horizontal ladder test. The best score was acquired for the first time in more than 90% of animals. The mean of strength on the grasping test was 133.46±12.08g for the right and 121.74±8.73g for the left anterior paw. There was a difference between the right and left sides. There was no difference between the groups according to sex. There is no statistical difference comparing all functional indexes between sex, independent of the side analyzed. The peroneal functional index showed higher levels than the sciatic and tibial functional index on both sides and sex. Conclusions The behavioral and functional assessment of peripheral nerve regeneration are low-cost, easy to perform, and reliable tests. However, they need to be performed by experienced researchers to avoid misinterpretation.(AU)

Avaliação radiográfica da profundidade do sulco troclear e diâmetro patelar em cães / Radiographic assessment of the depth of the troclear groove and patellar diameter in dogs

Background: Patellar luxation is an alteration of bone development for which the indicated treatment is surgery. Failure to correct it may result in clinical worsening. The most commonly used surgical approach is the transposition of the tibial crest with trochleoplasty, which aims to accommodate 50% of the patella in the trochlea. The femoral groove and trochlea can be evaluated radiographically by tangential projection, tomography, or ultrasonography; however, all these methodologies have limitations. The objective of this study was to evaluate the depth of the trochlear groove in three regions and to compare it with the patellar diameter on simple mediolateral radiographic images. Materials, Methods & Results: Fifty non-paired pelvic limbs of adult dogs of a specific breed, weighing less than 40 kg and without orthopedic changes, were used. In the mediolateral radiographic projection, three evaluators measured the femoral trochlear sulcus at three different points and the patellar diameter. After imaging examinations, all limbs were skeletonized, and the trochlea and patella were measured with a digital caliper in the same regions as that of the radiographic measurements. All post-skeletonization calculations were performed by an evaluator. The highest mean radiographic and ex vivo trochlear depth was 3.4 ± 1.2 mm and 2.7 ± 0.8 mm, respectively. The lowest mean radiographic and ex vivo patellar diameter was 7.7 ± 1.7 mm and 7.9 ± 1.6 mm, respectively. The average relationship between the trochlear depth and patellar diameter was less than 50% in all animals, with the highest radiographically determined ratio being 44.15% and that determined ex vivo as 34.17%. The mean patellar diameter calculated radiographically was similar among the animals. Discussion: Radiographic images made it possible to assess the patella and bone surface regions of the femoral condyles. A wide arthrotomy...

Infiltrative lipoma causing lumbar nerve root compression in a dog

Background: Lipomas are benign soft tissue mesenchymal neoplasms composed of adipose cells and are usually foundin the subcutaneous tissue. Occasionally, lipomas may invade muscles or grow between them, in which case they arecharacterized as infiltrative lipomas. Clinical signs resulting from an intermuscular lipoma compressing peripheral nervesare rarely encountered in dogs. This case report aims to describe the neurological signs, diagnosis, and clinical evaluationof a dog diagnosed with infiltrative lipoma compressing a lumbar spinal nerve root.Case: A 12-year-old neutered male Fox Paulistinha, weighing 10.5 kg, was presented with difficulties in walking for thepast 15 days with no previous history of trauma. On physical examination, the presence of three cutaneous nodules wasnoted in the ventral thoracic region, with onset of one year and slow and progressive growth. A cytological evaluation ofthe nodules was performed, and lipoma was diagnosed. At the neurological examination, the patient presented ambulatoryparaparesis with marked motor deficit and atrophy of the quadriceps muscles of the left pelvic limb. Conscious proprioceptive deficit, the absence of patellar reflex, and diminished withdrawal reflex were observed in the left hind limb, in additionto diffuse pain on epaxial palpation of the lumbar region. Electroneuromyography showed increased insertion activity inthe left gastrocnemius muscle and moderate spontaneous activity (fibrillation). Persistence of 10% was observed in theF-wave study of the left tibial nerve. These findings indicate partial involvement of the roots of the left sciatic-tibial nerve.Magnetic resonance imaging (MRI) showed the presence of a mass measuring 3.18 × 1.04 × 1.4 cm, interspersed withthe paravertebral muscles, and located adjacent to the L2 and L3 spinous processes...

Infiltrative lipoma causing lumbar nerve root compression in a dog

Background: Lipomas are benign soft tissue mesenchymal neoplasms composed of adipose cells and are usually foundin the subcutaneous tissue. Occasionally, lipomas may invade muscles or grow between them, in which case they arecharacterized as infiltrative lipomas. Clinical signs resulting from an intermuscular lipoma compressing peripheral nervesare rarely encountered in dogs. This case report aims to describe the neurological signs, diagnosis, and clinical evaluationof a dog diagnosed with infiltrative lipoma compressing a lumbar spinal nerve root.Case: A 12-year-old neutered male Fox Paulistinha, weighing 10.5 kg, was presented with difficulties in walking for thepast 15 days with no previous history of trauma. On physical examination, the presence of three cutaneous nodules wasnoted in the ventral thoracic region, with onset of one year and slow and progressive growth. A cytological evaluation ofthe nodules was performed, and lipoma was diagnosed. At the neurological examination, the patient presented ambulatoryparaparesis with marked motor deficit and atrophy of the quadriceps muscles of the left pelvic limb. Conscious proprioceptive deficit, the absence of patellar reflex, and diminished withdrawal reflex were observed in the left hind limb, in additionto diffuse pain on epaxial palpation of the lumbar region. Electroneuromyography showed increased insertion activity inthe left gastrocnemius muscle and moderate spontaneous activity (fibrillation). Persistence of 10% was observed in theF-wave study of the left tibial nerve. These findings indicate partial involvement of the roots of the left sciatic-tibial nerve.Magnetic resonance imaging (MRI) showed the presence of a mass measuring 3.18 × 1.04 × 1.4 cm, interspersed withthe paravertebral muscles, and located adjacent to the L2 and L3 spinous processes...(AU)

Bloqueios dos nervos ciático e femoral guiado por neuroestimulador em Chinchilla lanigera submetida a osteossíntese de tíbia / Nerve stimulator-guided ciatic and femoral nerve block during tibial osteosynthesis in Chinchilla lanigera

Background: Nociceptive stimulation in orthopedic surgery requires effective pain management to ensure trans andpostoperative patient comfort. Several techniques can be used for this, and multimodal analgesia protocols such as guidedlocoregional blocks provide a balanced effect, as they enable the use of low-dose anesthetics and offer rapid recovery. Thebenefits of specific nerve blocks in domestic animals are well known; however, there are few reports that have ascertainedtheir safety in wild species. This report is aimed at describing the successful use of neurolocalizer-guided sciatic andfemoral nerve blocks during tibial osteosyntheses in a chinchilla.Case: A 9-month-old chinchilla weighing 0.56 kg was referred for surgery for proximal and mid-diaphyseal tibia fracturesresulting from trauma. Following preanesthetic evaluation, the animal received intramuscular dexmedetomidine (15 µgkg1) as preanesthetic medication. Sedation was apparent after 15 min and was verified by a decreased activity, the animalallowing manipulation, absence of the eyelid and righting reflexes, and limb movement after clamping removal of limbafter clamping. After achieving sedation, anesthesia was induced and maintained with sevoflurane (FiO2 = 1.0), suppliedthrough a nasoral mask. Sciatic and femoral nerve blocks were performed with the aid of a neurostimulator. A needle wasinserted into the femoral triangle, cranial to the femoral artery, and into the depression between the sciatic tuberosity andthe greater femoral trochanter. The neurostimulator was set at a pulse frequency of 1 Hz, pulse duration of 0.1 ms andinitial current of 0.6 mA. The needle was advanced toward the nerves until muscle contractions were observed, and thecurrent was gradually reduced until contractions were manifested at a minimum current...

Bloqueios dos nervos ciático e femoral guiado por neuroestimulador em Chinchilla lanigera submetida a osteossíntese de tíbia / Nerve stimulator-guided ciatic and femoral nerve block during tibial osteosynthesis in Chinchilla lanigera

Background: Nociceptive stimulation in orthopedic surgery requires effective pain management to ensure trans andpostoperative patient comfort. Several techniques can be used for this, and multimodal analgesia protocols such as guidedlocoregional blocks provide a balanced effect, as they enable the use of low-dose anesthetics and offer rapid recovery. Thebenefits of specific nerve blocks in domestic animals are well known; however, there are few reports that have ascertainedtheir safety in wild species. This report is aimed at describing the successful use of neurolocalizer-guided sciatic andfemoral nerve blocks during tibial osteosyntheses in a chinchilla.Case: A 9-month-old chinchilla weighing 0.56 kg was referred for surgery for proximal and mid-diaphyseal tibia fracturesresulting from trauma. Following preanesthetic evaluation, the animal received intramuscular dexmedetomidine (15 µgkg1) as preanesthetic medication. Sedation was apparent after 15 min and was verified by a decreased activity, the animalallowing manipulation, absence of the eyelid and righting reflexes, and limb movement after clamping removal of limbafter clamping. After achieving sedation, anesthesia was induced and maintained with sevoflurane (FiO2 = 1.0), suppliedthrough a nasoral mask. Sciatic and femoral nerve blocks were performed with the aid of a neurostimulator. A needle wasinserted into the femoral triangle, cranial to the femoral artery, and into the depression between the sciatic tuberosity andthe greater femoral trochanter. The neurostimulator was set at a pulse frequency of 1 Hz, pulse duration of 0.1 ms andinitial current of 0.6 mA. The needle was advanced toward the nerves until muscle contractions were observed, and thecurrent was gradually reduced until contractions were manifested at a minimum current...(AU)

Exostose cartilaginosa múltipla em um canino pediátrico / Multiple cartilaginous exostoses in a pediatric dog

Background: Multiple cartilaginous exostosis (MCE) is a rare neoplastic disease in dogs that is characterized by the presence of osteochondromas in multiple bones. MCE is a disorder of development during growth and maturation, the realetiology of which has yet to be elucidated, but is believed to have a genetic basis. Usually affected animals have a historyof a palpable mass on the bone surface, causing anatomical deformities and compression of adjacent structures. SinceMCE is a rare neoplastic disease in dogs it may be difficult to recognize in the clinic. The aim of this study was to reporta case of MCE in a pediatric dog.Case: A female 4-month-old Rottweiler dog with a history of bone neoformation on the left hind limb, anorexia, weightloss, and difficulty walking received clinical care. The disease had its initial onset 2 months prior. At physical examination, the animal showed paresis of the hind limbs and a bony tumor on the lateral part of the left tibia. A complete bloodcell count and serum biochemical profile were obtained. The only abnormality diagnosed was hyperproteinemia due tohyperglobulinemia. Other diagnostic tests were not authorized and the animal was euthanized. At the necropsy, an intrathoracic neoformation was observed from the sixth to the eighth rib on the right antimer. Some tumors were also observedon the fourth lumbar vertebra and between the first and the second sacral vertebra, and a left tibial tumor, which had beenobserved at physical examination. The sagittal section of the spine revealed the presence of extradural compression of thespinal cord due to vertebral proliferations with compression of the nerve roots. All of the proliferations had macroscopicsimilarities, being firm, sessile, irregular, and with complete adherence to deep planes. Tumor samples were submitted tohistopathological analysis and the tissue morphology was compatible with osteochondroma...

Exostose cartilaginosa múltipla em um canino pediátrico / Multiple cartilaginous exostoses in a pediatric dog

Background: Multiple cartilaginous exostosis (MCE) is a rare neoplastic disease in dogs that is characterized by the presence of osteochondromas in multiple bones. MCE is a disorder of development during growth and maturation, the realetiology of which has yet to be elucidated, but is believed to have a genetic basis. Usually affected animals have a historyof a palpable mass on the bone surface, causing anatomical deformities and compression of adjacent structures. SinceMCE is a rare neoplastic disease in dogs it may be difficult to recognize in the clinic. The aim of this study was to reporta case of MCE in a pediatric dog.Case: A female 4-month-old Rottweiler dog with a history of bone neoformation on the left hind limb, anorexia, weightloss, and difficulty walking received clinical care. The disease had its initial onset 2 months prior. At physical examination, the animal showed paresis of the hind limbs and a bony tumor on the lateral part of the left tibia. A complete bloodcell count and serum biochemical profile were obtained. The only abnormality diagnosed was hyperproteinemia due tohyperglobulinemia. Other diagnostic tests were not authorized and the animal was euthanized. At the necropsy, an intrathoracic neoformation was observed from the sixth to the eighth rib on the right antimer. Some tumors were also observedon the fourth lumbar vertebra and between the first and the second sacral vertebra, and a left tibial tumor, which had beenobserved at physical examination. The sagittal section of the spine revealed the presence of extradural compression of thespinal cord due to vertebral proliferations with compression of the nerve roots. All of the proliferations had macroscopicsimilarities, being firm, sessile, irregular, and with complete adherence to deep planes. Tumor samples were submitted tohistopathological analysis and the tissue morphology was compatible with osteochondroma...(AU)

Sciatic nerve injection palsy in a dog: electrodiagnostic testing and microsurgical treatment

Background: Iatrogenic damage to the ischiatic nerve is considered uncommon and may cause dysfunction with variable clinical signs dependent on type and severity of injury. Due to important role of this nerve in locomotion and weightbearing limb, a poor prognosis for recovery may be observed in many cases. Electromyography analysis may suggest the neuroanatomic localization, diagnosis information, and severity of lesion to determine better therapeutic intervention. Therefore, the aim of this report is to describe the possible cause, diagnosis and treatment of a postinjection ischiatic nerve injury in a dog with complete recovery.Case: A 3-year-old neutered male dachshund dog was referred to the Veterinary Hospital due to inability to weight support in the right hind limb after diminazene diaceturate intramuscular injection. The gait evaluation showed dropped-hock and knuckling into the digits of the right hind limb and neurologic examination revealed moderate muscle atrophy below to femorotibial joint of the right hind limb with sensory analgesia (superficial and deep) on the lateral, dorsal, and plantar surfaces, absent patellar reflex, and proprioceptive deficit. Electrophysiologic testing was done under general anesthesia in a 2-channel Nicolet Compass Meridian apparatus. Absence of compound muscle action potentials after right fibular and tibial nerve stimulations, and abnormal spontaneous activity in cranial tibial, gastrocnemius and deep digital extensor muscles were observed. A diagnosis of moderate/severe axonotmesis of sciatic nerve was achieved. Under microscope magnification, all adherent adjacent tissue and epineural sheat were removed. Due this, a small epineural window was created. On neurological examination performed 30 days after surgery, complete recovery of sensitivity of the right hind limb, and normal proprioception were observed. The muscle atrophy was also noted to have improved.[...]

Sciatic nerve injection palsy in a dog: electrodiagnostic testing and microsurgical treatment

Background: Iatrogenic damage to the ischiatic nerve is considered uncommon and may cause dysfunction with variable clinical signs dependent on type and severity of injury. Due to important role of this nerve in locomotion and weightbearing limb, a poor prognosis for recovery may be observed in many cases. Electromyography analysis may suggest the neuroanatomic localization, diagnosis information, and severity of lesion to determine better therapeutic intervention. Therefore, the aim of this report is to describe the possible cause, diagnosis and treatment of a postinjection ischiatic nerve injury in a dog with complete recovery.Case: A 3-year-old neutered male dachshund dog was referred to the Veterinary Hospital due to inability to weight support in the right hind limb after diminazene diaceturate intramuscular injection. The gait evaluation showed dropped-hock and knuckling into the digits of the right hind limb and neurologic examination revealed moderate muscle atrophy below to femorotibial joint of the right hind limb with sensory analgesia (superficial and deep) on the lateral, dorsal, and plantar surfaces, absent patellar reflex, and proprioceptive deficit. Electrophysiologic testing was done under general anesthesia in a 2-channel Nicolet Compass Meridian apparatus. Absence of compound muscle action potentials after right fibular and tibial nerve stimulations, and abnormal spontaneous activity in cranial tibial, gastrocnemius and deep digital extensor muscles were observed. A diagnosis of moderate/severe axonotmesis of sciatic nerve was achieved. Under microscope magnification, all adherent adjacent tissue and epineural sheat were removed. Due this, a small epineural window was created. On neurological examination performed 30 days after surgery, complete recovery of sensitivity of the right hind limb, and normal proprioception were observed. The muscle atrophy was also noted to have improved.[...](AU)

Effect of Sciatic Nerve Transection on acetylcholinesterase activity in spinal cord and skeletal muscles of the bullfrog Lithobates catesbeianus / Efeito da Secção do Nervo Isquiático sobre a atividade da acetilcolinesterase em medula espinal e músculos esqueléticos da rã-touro Lithobates catesbeianus

Sciatic nerve transection (SNT), a model for studying neuropathic pain, mimics the clinical symptoms of "phantom limb", a pain condition that arises in humans after amputation or transverse spinal lesions. In some vertebrate tissues, this condition decreases acetylcholinesterase (AChE) activity, the enzyme responsible for fast hydrolysis of released acetylcholine in cholinergic synapses. In spinal cord of frog Rana pipiens, this enzymes activity was not significantly changed in the first days following ventral root transection, another model for studying neuropathic pain. An answerable question is whether SNT decreases AChE activity in spinal cord of frog Lithobates catesbeianus, a species that has been used as a model for studying SNT-induced neuropathic pain. Since each animal model has been created with a specific methodology, and the findings tend to vary widely with slight changes in the method used to induce pain, our study assessed AChE activity 3 and 10 days after complete SNT in lumbosacral spinal cord of adult male bullfrog Lithobates catesbeianus. Because there are time scale differences of motor endplate maturation in rat skeletal muscles, our study also measured the AChE activity in bullfrog tibial posticus (a postural muscle) and gastrocnemius (a typical skeletal muscle that is frequently used to study the motor system) muscles. AChE activity did not show significant changes 3 and 10 days following SNT in spinal cord. Also, no significant change occurred in AChE activity in tibial posticus and gastrocnemius muscles at day 3. However, a significant decrease was found at day 10, with reductions of 18% and 20% in tibial posticus and gastrocnemius, respectively. At present we cannot explain this change in AChE activity. While temporally different, the direction of the change was similar to that described for rats.[...](AU)

A transecção do nervo isquiático (SNT), um modelo para estudar dor neuropática, simula os sintomas clínicos do membro fantasma, uma condição dolorosa que ocorre nos humanos após amputação ou secção completa da medula espinal. Essa condição muda a atividade da acetilcolinesterase (AChE), a enzima responsável pela rápida hidrólise da acetilcolina liberada nas sinapses colinérgicas, em alguns tecidos de vertebrados. Em medula espinal de rã Rana pipiens, a atividade da AChE não foi significativamente alterada nos primeiros dias após a secção da raiz ventral, outro modelo para o estudo da dor neuroptípica. Uma questão ainda não respondida é se a SNT diminui a atividade da AChE na medula espinal de rã Lithobates catesbeianus, uma espécie que vem sendo usada como modelo em estudos da dor neuropática induzida por SNT. Como cada modelo animal é criado a partir de metodologia específica, e seus resultados tendem a variar com pequenas mudanças na metodologia de indução da dor, o presente estudo avaliou a atividade da AChE em medula espinal lombossacral de rã-touro Lithobates catesbeianus, adultos, machos, 3 e 10 dias após a completa SNT. Como há diferenças temporais na maturação de placas motoras em músculos esqueléticos de ratos, nosso estudo ainda demonstrou, na rã-touro, os efeitos da SNT sobre a atividade da AChE nos músculos esqueléticos tibial posticus, um músculo postural, e gastrocnêmio, um músculo frequentemente usado em estudos do sistema motor. A atividade da AChE não mudou significativamente na medula espinal aos 3 e 10 dias após a SNT. Nos músculos, a atividade não alterou significativamente aos 3 dias após a lesão, mas reduziu de forma significativa aos 10 dias após a SNT. Aos 10 dias, a diminuição foi 18% no músculo tibial posticus e 20% no gastrocnêmio. No momento, nós não temos explicação para essa mudança na atividade da AChE. Embora temporalmente diferente, o sentido da mudança é similar ao que é descrito em ratos.[...](AU)

Mapeamento comparativo de nervos periféricos em caninos e bovinos / Comparative mapping of peripheral nerves in dogs and cattle

O estudo dos dados anatômicos é fundamental para possibilitar ao médico veterinário o reconhecimento de pequenas estruturas, como os nervos nos animais, oferecendo subsídio para construção do conhecimento do profissional principalmente em técnicas anestésicas e cirúrgicas. Para investigar e mapear os nervos do plexo braquial (nervo radial, nervo musculocutâneo, nervo ulnar, nervo mediano), nervo isquiático, nervo tibial, nervo femoral e os nervos para bloqueio paravertebral, foram utilizados um cadáver canino adulto, de peso aproximado de 8kg, e um cadáver de bezerro Holandês, de peso aproximado de 40kg. O mapeamento dos nervos é de grande importância, já que conhecer bem essas estruturas permite ao veterinário um bom desenvolvimento de suas atividades profissionais a fim de exercer funções mais complexas durante a anestesia e cirurgia veterinária, uma vez que, identificados os pontos de referência anatômicos, é possível trabalhar com mais clareza nas técnicas de bloqueios dos nervos periféricos.(AU)

Knowledge of animal anatomy is essential for the veterinarian to identify small structures such as nerves, thus providing a solid background for the professional especially for surgical and anesthetic techniques. To investigate and map the nerves of the brachial plexus (radial, musculocutaneous, ulnar, median), sciatic, tibial, femoral and the nerves for paravertebral blocking in bovine, embalmed specimens were used. One adult male dog weighing approximately 8kg and one 40kg male calf were used. Nerve mapping is fundamental due to its interdisciplinary nature, thus providing the veterinarian with a major improvement in his/her professional activities which permits allows one to perform complex tasks in anesthesia and veterinary surgery. Knowledge ofanatomical reference points increases clarity and precision in techniques involving peripheral nerve blocks.(AU)

Mapeamento comparativo de nervos periféricos em caninos e bovinos / Comparative mapping of peripheral nerves in dogs and cattle

O estudo dos dados anatômicos é fundamental para possibilitar ao médico veterinário o reconhecimento de pequenas estruturas, como os nervos nos animais, oferecendo subsídio para construção do conhecimento do profissional principalmente em técnicas anestésicas e cirúrgicas. Para investigar e mapear os nervos do plexo braquial (nervo radial, nervo musculocutâneo, nervo ulnar, nervo mediano), nervo isquiático, nervo tibial, nervo femoral e os nervos para bloqueio paravertebral, foram utilizados um cadáver canino adulto, de peso aproximado de 8kg, e um cadáver de bezerro Holandês, de peso aproximado de 40kg. O mapeamento dos nervos é de grande importância, já que conhecer bem essas estruturas permite ao veterinário um bom desenvolvimento de suas atividades profissionais a fim de exercer funções mais complexas durante a anestesia e cirurgia veterinária, uma vez que, identificados os pontos de referência anatômicos, é possível trabalhar com mais clareza nas técnicas de bloqueios dos nervos periféricos.(AU)

Knowledge of animal anatomy is essential for the veterinarian to identify small structures such as nerves, thus providing a solid background for the professional especially for surgical and anesthetic techniques. To investigate and map the nerves of the brachial plexus (radial, musculocutaneous, ulnar, median), sciatic, tibial, femoral and the nerves for paravertebral blocking in bovine, embalmed specimens were used. One adult male dog weighing approximately 8kg and one 40kg male calf were used. Nerve mapping is fundamental due to its interdisciplinary nature, thus providing the veterinarian with a major improvement in his/her professional activities which permits allows one to perform complex tasks in anesthesia and veterinary surgery. Knowledge ofanatomical reference points increases clarity and precision in techniques involving peripheral nerve blocks.(AU)

Comparative study between standard and inside-out vein graft techniques on sciatic nerve repair of rats: muscular and functional analysis

Purpose: To compare the functional result of standart vein grafts and inside-out vein graft technique on sciatic nerve repair. Methods: We used 24 male Wistar rats divided into 4 groups: control group (CG), standard vein graft group (SVG), Inside-out vein graft group (IOVG) and denervated Group (DG). SVG, IOVG and DG underwent total section of the sciatic nerve, SVG and IOVG however underwent nerve repair surgery using a graft with normal jugular vein and inside-out jugular vein, respectively. Histological analysis of the soleus and Extensor Digitorum Longus (EDL), and Sciatic Functional Index were used to compare the results after 6 weeks. Results: Both grafts acted favorably in muscle recovery and improved functionality; They were similar in all parameters, however, in more points SVG achieved similar to the CG, in the other hand IOVG more times was similar to DG. Fact that makes the graft with normal vein the most viable option between the two options. Conclusion: Both types of grafts acted beneficially wherein the graft normal vein has proved to be the best option.(AU)

Effect of Sciatic Nerve Transection on acetylcholinesterase activity in spinal cord and skeletal muscles of the bullfrog Lithobates catesbeianus

Abstract Sciatic nerve transection (SNT), a model for studying neuropathic pain, mimics the clinical symptoms of phantom limb, a pain condition that arises in humans after amputation or transverse spinal lesions. In some vertebrate tissues, this condition decreases acetylcholinesterase (AChE) activity, the enzyme responsible for fast hydrolysis of released acetylcholine in cholinergic synapses. In spinal cord of frog Rana pipiens, this enzymes activity was not significantly changed in the first days following ventral root transection, another model for studying neuropathic pain. An answerable question is whether SNT decreases AChE activity in spinal cord of frog Lithobates catesbeianus, a species that has been used as a model for studying SNT-induced neuropathic pain. Since each animal model has been created with a specific methodology, and the findings tend to vary widely with slight changes in the method used to induce pain, our study assessed AChE activity 3 and 10 days after complete SNT in lumbosacral spinal cord of adult male bullfrog Lithobates catesbeianus. Because there are time scale differences of motor endplate maturation in rat skeletal muscles, our study also measured the AChE activity in bullfrog tibial posticus (a postural muscle) and gastrocnemius (a typical skeletal muscle that is frequently used to study the motor system) muscles. AChE activity did not show significant changes 3 and 10 days following SNT in spinal cord. Also, no significant change occurred in AChE activity in tibial posticus and gastrocnemius muscles at day 3. However, a significant decrease was found at day 10, with reductions of 18% and 20% in tibial posticus and gastrocnemius, respectively. At present we cannot explain this change in AChE activity. While temporally different, the direction of the change was similar to that described for rats. This similarity indicates that bullfrog is a valid model for investigating AChE activity following SNT.

Resumo A transecção do nervo isquiático (SNT), um modelo para estudar dor neuropática, simula os sintomas clínicos do membro fantasma, uma condição dolorosa que ocorre nos humanos após amputação ou secção completa da medula espinal. Essa condição muda a atividade da acetilcolinesterase (AChE), a enzima responsável pela rápida hidrólise da acetilcolina liberada nas sinapses colinérgicas, em alguns tecidos de vertebrados. Em medula espinal de rã Rana pipiens, a atividade da AChE não foi significativamente alterada nos primeiros dias após a secção da raiz ventral, outro modelo para o estudo da dor neuropática. Uma questão ainda não respondida é se a SNT diminui a atividade da AChE na medula espinal de rã Lithobates catesbeianus, uma espécie que vem sendo usada como modelo em estudos da dor neuropática induzida por SNT. Como cada modelo animal é criado a partir de metodologia específica, e seus resultados tendem a variar com pequenas mudanças na metodologia de indução da dor, o presente estudo avaliou a atividade da AChE em medula espinal lombossacral de rã-touro Lithobates catesbeianus, adultos, machos, 3 e 10 dias após a completa SNT. Como há diferenças temporais na maturação de placas motoras em músculos esqueléticos de ratos, nosso estudo ainda demonstrou, na rã-touro, os efeitos da SNT sobre a atividade da AChE nos músculos esqueléticos tibial posticus, um músculo postural, e gastrocnêmio, um músculo frequentemente usado em estudos do sistema motor. A atividade da AChE não mudou significativamente na medula espinal aos 3 e 10 dias após a SNT. Nos músculos, a atividade não alterou significativamente aos 3 dias após a lesão, mas reduziu de forma significativa aos 10 dias após a SNT. Aos 10 dias, a diminuição foi 18% no músculo tibial posticus e 20% no gastrocnêmio. No momento, nós não temos explicação para essa mudança na atividade da AChE. Embora temporalmente diferente, o sentido da mudança é similar ao que é descrito em ratos. Esta similaridade torna a rã-touro um modelo válido para se estudar questões ainda não respondidas da SNT sobre a AChE.

Effect of Sciatic Nerve Transection on acetylcholinesterase activity in spinal cord and skeletal muscles of the bullfrog Lithobates catesbeianus

Abstract Sciatic nerve transection (SNT), a model for studying neuropathic pain, mimics the clinical symptoms of phantom limb, a pain condition that arises in humans after amputation or transverse spinal lesions. In some vertebrate tissues, this condition decreases acetylcholinesterase (AChE) activity, the enzyme responsible for fast hydrolysis of released acetylcholine in cholinergic synapses. In spinal cord of frog Rana pipiens, this enzymes activity was not significantly changed in the first days following ventral root transection, another model for studying neuropathic pain. An answerable question is whether SNT decreases AChE activity in spinal cord of frog Lithobates catesbeianus, a species that has been used as a model for studying SNT-induced neuropathic pain. Since each animal model has been created with a specific methodology, and the findings tend to vary widely with slight changes in the method used to induce pain, our study assessed AChE activity 3 and 10 days after complete SNT in lumbosacral spinal cord of adult male bullfrog Lithobates catesbeianus. Because there are time scale differences of motor endplate maturation in rat skeletal muscles, our study also measured the AChE activity in bullfrog tibial posticus (a postural muscle) and gastrocnemius (a typical skeletal muscle that is frequently used to study the motor system) muscles. AChE activity did not show significant changes 3 and 10 days following SNT in spinal cord. Also, no significant change occurred in AChE activity in tibial posticus and gastrocnemius muscles at day 3. However, a significant decrease was found at day 10, with reductions of 18% and 20% in tibial posticus and gastrocnemius, respectively. At present we cannot explain this change in AChE activity. While temporally different, the direction of the change was similar to that described for rats. This similarity indicates that bullfrog is a valid model for investigating AChE activity following SNT.

Resumo A transecção do nervo isquiático (SNT), um modelo para estudar dor neuropática, simula os sintomas clínicos do membro fantasma, uma condição dolorosa que ocorre nos humanos após amputação ou secção completa da medula espinal. Essa condição muda a atividade da acetilcolinesterase (AChE), a enzima responsável pela rápida hidrólise da acetilcolina liberada nas sinapses colinérgicas, em alguns tecidos de vertebrados. Em medula espinal de rã Rana pipiens, a atividade da AChE não foi significativamente alterada nos primeiros dias após a secção da raiz ventral, outro modelo para o estudo da dor neuropática. Uma questão ainda não respondida é se a SNT diminui a atividade da AChE na medula espinal de rã Lithobates catesbeianus, uma espécie que vem sendo usada como modelo em estudos da dor neuropática induzida por SNT. Como cada modelo animal é criado a partir de metodologia específica, e seus resultados tendem a variar com pequenas mudanças na metodologia de indução da dor, o presente estudo avaliou a atividade da AChE em medula espinal lombossacral de rã-touro Lithobates catesbeianus, adultos, machos, 3 e 10 dias após a completa SNT. Como há diferenças temporais na maturação de placas motoras em músculos esqueléticos de ratos, nosso estudo ainda demonstrou, na rã-touro, os efeitos da SNT sobre a atividade da AChE nos músculos esqueléticos tibial posticus, um músculo postural, e gastrocnêmio, um músculo frequentemente usado em estudos do sistema motor. A atividade da AChE não mudou significativamente na medula espinal aos 3 e 10 dias após a SNT. Nos músculos, a atividade não alterou significativamente aos 3 dias após a lesão, mas reduziu de forma significativa aos 10 dias após a SNT. Aos 10 dias, a diminuição foi 18% no músculo tibial posticus e 20% no gastrocnêmio. No momento, nós não temos explicação para essa mudança na atividade da AChE. Embora temporalmente diferente, o sentido da mudança é similar ao que é descrito em ratos. Esta similaridade torna a rã-touro um modelo válido para se estudar questões ainda não respondidas da SNT sobre a AChE.