The median nerve consistently drives flexion of the distal phalanx of the ring and little fingers: Interest in finger flexion reconstruction by nerve transfers.

Surgeons believe that in high ulnar nerve lesion distal interphalangeal joint (DIP) flexion of the ring and little finger is abolished. In this article, we present the results of a study on innervation of the flexor digitorum profundus of the ring and little fingers in five patients with high ulnar nerve injury and in 19 patients with a brachial plexus, posterior cord, or radial nerve injury. Patients with ulnar nerve lesion were assessed clinically and during surgery for ulnar nerve repair we confirmed complete lesion of the ulnar nerve in all cases. In the remaining 19 patients, during surgery, either the median nerve (MN) or the anterior interosseous nerve (AIN) was stimulated electrically and DIP flexion of the ring and little fingers evaluated. All patients with high ulnar nerve lesions had active DIP flexion of the ring and little fingers. Strength scored M4 in the ring and M3-M4 in the little finger. Electrical stimulation of either the MN or AIN produced DIP flexion of the ring and little fingers. Contrary to common knowledge, we identified preserved flexion of the distal phalanx of the ring and little fingers in high ulnar nerve lesions. On the basis of these observations, nerve transfers to the AIN may provide flexion of all fingers.

[Interscalene block for total shoulder arthroplasty: comparative study (ultrasound vs. neurostimulation)]. / Bloqueo interescalénico para artroplastia total de hombro: estudio comparativo ultrasonido vs neuroestimulación.

BACKGROUND: Modern anesthesiology has integrated the use of ultrasonography as a tool that has displaced neurostimulation as a technique for locating peripheral nerves. The aim of this study was to determine which procedure is more effective for guiding interscalene block for total shoulder arthroplasty. METHODS: We carried out a comparative, prospective non-randomized study comprised of the group guided by neurostimulation interscalene block and the group guided by ultrasound. All patients in both groups were scheduled for total shoulder arthroplasty. Latency, degree of sensory and motor block, success rate, postoperative pain intensity at 6, 12, and 24 h, patient satisfaction and complications were measured. RESULTS: We included 110 patients, 55 per group. Patients were placed in beach chair position and the deltopectoral approach was used. There were no differences in demographic characteristics. Results for neurostimulation vs. ultrasound group: latency 19.11 ± 2.27 vs. 17.24 ± 1.42 min, p= 0.23. Block sensitivity in both groups was grade 0 motor block grade 0 in 76.4% and grade 1 in 23.6% vs. grade 0 to 100%. There was 100% success rate for both groups. Postoperative pain at 6 h was 0.13 ± 0.54 vs. 0.11 ± 0.13 p= 0.90, at 12 h 1.67 ± 1.15 vs. 1.65 ± 0.59 p= 0.89 and at 24 h 3.15 ± 1.66 vs. 2.99 ± 1.15 p= 0.78. Satisfaction 54.5% very satisfied and 45.5% satisfied 96.36% vs 3.6% very satisfied and satisfied. Complications 18.18% vs. 3.6% p= 0.023. CONCLUSION: Ultrasound-guided interscalene nerve block is the technique of choice in elective total shoulder arthroplasty.

ANTECEDENTES: la anestesiología moderna ha integrado a la ultrasonografía como una herramienta que ha desplazado a la neuroestimulación como técnica de localización de nervios periféricos: ¿cuál es más efectiva para guiar el bloqueo interescalénico en artroplastia total de hombro? OBJETIVO: comparar dos técnicas de localización del plexo braquial bloqueo interescalénico como técnica anestésica en artroplastia total de hombro. MATERIAL Y MÉTODOS: estudio comparativo, prospectivo, sin asignación al azar. Se incluyeron todos los pacientes programados para artroplastia total de hombro; se formaron 2 grupos: grupo neuroestimulación donde el bloqueo interescalénico fue guiado por neuroestimulación, grupo ultrasonido que fue guiado por ultrasonido. Se midió el tiempo de latencia, grado de bloqueo sensitivo y motor, tasa de éxito, intensidad del dolor postoperatorio a las 6, 12 y 24 horas, satisfacción, y complicaciones. RESULTADOS: se incluyeron 110 pacientes, 55 por grupo, posición de silla de playa y abordaje deltopectoral. No hubo diferencias en las características demográficas, neuroestimulación vs ultrasonografía: latencia 19.11 ± 2.27 vs 17.24 ± 1.42 minutos p= 0.23. Bloqueo sensitivo en ambos grupos grado 0, bloqueo motor grado 0 en 76.4% y grado 1 en 23.6%, vs grado 0 en 100%. Tasa de éxito 100% en ambos grupos, dolor postoperatorio 6 horas 0.13 ± 0.54 vs 0.11 ± 0.13 p= 0.90; 12 horas de 1.67 ± 1.15 vs 1.65 ± 0.59 p= 0.89, 24 horas 3.15± 1.66 vs 2.99 ± 1.15 p= 0.78. Satisfacción: 54.5% muy satisfecho, y 45.5% satisfecho vs 96.36% muy satisfecho y 3.6% satisfecho. Complicaciones 18.18% vs 3.6% p= 0.023. CONCLUSIÓN: el ultrasonido es la técnica de localización del plexo braquial de elección en artroplastia total de hombro.

Descrição do plexo braquial do cachorro-do-mato (Cerdocyon Thous Linnaeus, 1766) / Description of plexus brachial of crab-eating foxes (Cerdocyon Thous Linnaeus, 1766)

The Cerdocyon thous is a canid that has a wide distribution in South America and, besides some general aspects, its morphology is little known in the literature, especially regarding the nervous system. With the aim of elucidating the anatomical composition of brachial plexus, we studied three male specimens from Paragominas-PA, donated to the Morphological Laboratory of Animal Research (LaPMA), Federal Rural University of Amazonia (UFRA), after death by trampling. The animals were fixed in an aqueous solution of 10% formaldehyde for bilateral dissection of the origin of the brachial plexus. The brachial plexus of C. thous is derived from the last three cervical nerves and the first thoracic nerve (C6-T1). The main nerves that compose it, with their respective origins were the suprascapular nerve, subscapular nerve and musculocutaneous nerve (C6-C7), axillary nerve (C7-C8), radial nerve (C7-T1 and C7-C8), median nerve, ulnar nerve, thoracodorsal and thoracic lateral nerve (C8-T1). We conclude that the brachial plexus of C. thous is similar to that described for the domestic dogs, showing small differences in the composition of some nerves.

O Cerdocyon thous é um canídeo que possui ampla distribuição na América do Sul e salvo aspectos gerais, têm sua morfologia pouco conhecida na literatura, principalmente no que tange ao sistema nervoso. Com o objetivo de elucidar a composição anatômica do plexo braquial, estudou-se três exemplares machos provenientes de Paragominas-PA doados após morte por atropelamento ao Laboratório de Pesquisa Morfológica Animal (LaPMA), da Universidade Federal Rural da Amazônia (UFRA), os quais foram fixados em solução aquosa de formol 10%  para posterior realização da dissecação bilateral da origem do plexo braquial. O plexo braquial do C. thous é derivado dos três últimos nervos espinhais cervicais e do primeiro nervo torácico (C6-T1). Os principais nervos que o compõe, com suas respectivas origens foram: n. supraescapular, n. subscapular e n. musculocutâneo (C6 -C7), n. axilar (C7-C8), n. radial (C7-T1 e C7-C8), n. mediano, n. ulnar, n. toracodorsal e n. torácico lateral (C8-T1). Concluímos que o plexo braquial do C. thous assemelha-se ao descrito para os cães domésticos, apresentando pequenas diferenças quanto à composição de alguns nervos.

Descrição do plexo braquial do cachorro-do-mato (Cerdocyon Thous Linnaeus, 1766) / Description of plexus brachial of crab-eating foxes (Cerdocyon Thous Linnaeus, 1766)

The Cerdocyon thous is a canid that has a wide distribution in South America and, besides some general aspects, its morphology is little known in the literature, especially regarding the nervous system. With the aim of elucidating the anatomical composition of brachial plexus, we studied three male specimens from Paragominas-PA, donated to the Morphological Laboratory of Animal Research (LaPMA), Federal Rural University of Amazonia (UFRA), after death by trampling. The animals were fixed in an aqueous solution of 10% formaldehyde for bilateral dissection of the origin of the brachial plexus. The brachial plexus of C. thous is derived from the last three cervical nerves and the first thoracic nerve (C6-T1). The main nerves that compose it, with their respective origins were the suprascapular nerve, subscapular nerve and musculocutaneous nerve (C6-C7), axillary nerve (C7-C8), radial nerve (C7-T1 and C7-C8), median nerve, ulnar nerve, thoracodorsal and thoracic lateral nerve (C8-T1). We conclude that the brachial plexus of C. thous is similar to that described for the domestic dogs, showing small differences in the composition of some nerves.(AU)

O Cerdocyon thous é um canídeo que possui ampla distribuição na América do Sul e salvo aspectos gerais, têm sua morfologia pouco conhecida na literatura, principalmente no que tange ao sistema nervoso. Com o objetivo de elucidar a composição anatômica do plexo braquial, estudou-se três exemplares machos provenientes de Paragominas-PA doados após morte por atropelamento ao Laboratório de Pesquisa Morfológica Animal (LaPMA), da Universidade Federal Rural da Amazônia (UFRA), os quais foram fixados em solução aquosa de formol 10%  para posterior realização da dissecação bilateral da origem do plexo braquial. O plexo braquial do C. thous é derivado dos três últimos nervos espinhais cervicais e do primeiro nervo torácico (C6-T1). Os principais nervos que o compõe, com suas respectivas origens foram: n. supraescapular, n. subscapular e n. musculocutâneo (C6 -C7), n. axilar (C7-C8), n. radial (C7-T1 e C7-C8), n. mediano, n. ulnar, n. toracodorsal e n. torácico lateral (C8-T1). Concluímos que o plexo braquial do C. thous assemelha-se ao descrito para os cães domésticos, apresentando pequenas diferenças quanto à composição de alguns nervos.(AU)

Estudio morfométrico comparativo entre los músculos bíceps braquial y braquial con el objetivo de establecer el principal músculo flexor del codo / Comparative morphometric study among the brachial and brachial biceps muscles with objective of choosing the main muscle of the flexing of the elbow

El presente trabajo se propone comparar los diámetros de los vientres del músculo bíceps braquial y músculo braquial con el objeto de esclarecer algunas dudas sobre cuál sería el músculo más potente en la flexión del antebrazo. Las comparaciones fueron realizadas en 50 miembros superiores de cadáveres fijados. Se hizo evidente la diferencia promedio de 0,51 cm (5,8 por ciento) en el diámetro del vientre muscular del músculo braquial, ratificando lo encontrado en la revisión bibliográfica, donde el músculo braquial es un importante flexor del codo.

The present work seeks to compare the diameter of the wombs of the muscle brachial biceps and m. brachial in the intention of settling the doubts on which would be the most potent muscle in the flexing of the forearm. The measures were accomplished in 50 superior members of fastened corpses. A medium difference of 0.51 cm (5.8 percent) was evident in the diameter of the muscular womb the largest for m. brachial, ratifying what was found in the bibliographical revision, that brachial muscle is an important flexor of the elbow.

Carpal tunnel syndrome in the elderly: nerve conduction parameters.

OBJECTIVE: To establish nerve conduction parameters for carpal tunnel syndrome (CTS) electrodiagnosis in the elderly. METHOD: Thirty healthy subjects (65-86 years), 9 male and 21 female, were studied. Routine median and ulnar sensory and motor nerve conduction studies, median mixed palmar latency, comparative latency techniques median to ulnar (sensory, mixed and motor lumbrical-interossei), median to radial (sensory), and combined sensory index (CSI) were performed in both hands. RESULTS: The upper limits of normality (97.5%) were: median sensory distal latency 3.80 ms (14 cm); median motor distal latency 4.30 ms (8 cm); median palmar latency 2.45 ms (8 cm); lumbrical-interossei latency difference 0.60 ms (8 cm); comparative median to radial 0.95 ms (10 cm); comparative median to ulnar 0.95 ms (14 cm); comparative palmar median to ulnar 0.50 ms (8 cm); and CSI 2.20 ms. Sensory and mixed latencies were measured at peak. CONCLUSION: Our results establish new nerve conduction parameters for mild CTS electrodiagnosis in the elderly and will be helpful to reduce the number of false positive cases in this age.

Carpal tunnel syndrome in the elderly: nerve conduction parameters / Síndrome do túnel do carpo em idosos: parâmetros de condução nervosa

Objective: To establish nerve conduction parameters for carpal tunnel syndrome (CTS) electrodiagnosis in the elderly. Method: Thirty healthy subjects (65-86 years), 9 male and 21 female, were studied. Routine median and ulnar sensory and motor nerve conduction studies, median mixed palmar latency, comparative latency techniques median to ulnar (sensory, mixed and motor lumbrical-interossei), median to radial (sensory), and combined sensory index (CSI) were performed in both hands. Results: The upper limits of normality (97.5 percent) were: median sensory distal latency 3.80 ms (14 cm); median motor distal latency 4.30 ms (8 cm); median palmar latency 2.45 ms (8 cm); lumbrical-interossei latency difference 0.60 ms (8 cm); comparative median to radial 0.95 ms (10 cm); comparative median to ulnar 0.95 ms (14 cm); comparative palmar median to ulnar 0.50 ms (8 cm); and CSI 2.20 ms. Sensory and mixed latencies were measured at peak. Conclusion: Our results establish new nerve conduction parameters for mild CTS electrodiagnosis in the elderly and will be helpful to reduce the number of false positive cases in this age.

Objetivo: Estabelecer parâmetros de condução nervosa para o eletrodiagnóstico da síndrome do túnel do carpo (STC) em idosos. Método: Foram estudadas 30 pessoas idosas (65-86 anos) saudáveis. Foi realizado estudo de condução nervosa sensitiva e motora rotineira dos nervos mediano e ulnar, latência palmar mista do mediano, técnicas de comparação de latências mediano-ulnar (sensitivo, misto e motor lumbrical-interósseo) e mediano-radial (sensitivo) e índice sensitivo combinado (ISC) em ambas as mãos. Resultados: Os limites superiores de normalidade, 97,5 por cento foram: latência distal sensitiva do mediano 3,80 ms (14 cm); latência distal motora do mediano 4,30 ms (8 cm), latência palmar do mediano 2,45 ms (8 cm), diferença de latência lumbrical-interósseo 0,60 ms (8 cm), comparação mediano-radial 0,95 ms (10 cm), comparação mediano-ulnar 0,95 ms (14 cm), comparação mediano-ulnar palmar 0,50 ms (8 cm) e ISC 2,20 ms. As latências sensitivas e mistas foram medidas no pico. Conclusão: Nossos resultados estabelecem novos valores de condução nervosa para o eletrodiagnóstico da STC leve em idosos.

Neuropathic pain-like behavior after brachial plexus avulsion in mice: the relevance of kinin B1 and B2 receptors.

The relevance of kinin B(1) (B(1)R) and B(2) (B(2)R) receptors in the brachial plexus avulsion (BPA) model was evaluated in mice, by means of genetic and pharmacological tools. BPA-induced hypernociception was absent in B(1)R, but not in B(2)R, knock-out mice. Local or intraperitoneal administration of the B(2)R antagonist Hoe 140 failed to affect BPA-induced mechanical hypernociception. Interestingly, local or intraperitoneal treatment with B(1)R antagonists, R-715 or SSR240612, dosed at the time of surgery, significantly reduced BPA-evoked mechanical hypernociception. Intrathecal or intracerebroventricular administration of these antagonists, at the surgery moment, did not prevent the hypernociception. Both antagonists, dosed by intraperitoneal or intrathecal routes (but not intracerebroventricularly) 4 d after the surgery, significantly inhibited the mechanical hypernociception. At 30 d after the BPA, only the intracerebroventricular treatment effectively reduced the hypernociception. A marked increase in B(1)R mRNA was observed in the hypothalamus, hippocampus, thalamus, and cortex at 4 d after BPA and only in the hypothalamus and cortex at 30 d. In the spinal cord, a slight increase in B(1)R mRNA expression was observed as early as at 2 d. Finally, an enhancement of B(1)R protein expression was found in all the analyzed brain structures at 4 and 30 d after the BPA, whereas in the spinal cord, this parameter was augmented only at 4 d. The data provide new evidence on the role of peripheral and central kinin B(1)R in the BPA model of neuropathic pain. Selective B(1)R antagonists might well represent valuable tools for the management of neuropathic pain.

The role of neurotrophic factors in genesis and maintenance of mechanical hypernociception after brachial plexus avulsion in mice.

Neurotrophic factors (NTFs), namely nerve growth factor (NGF), glial cell line-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), have recently emerged as a new exciting class of potential targets for the development of drugs to treat chronic pain. We have recently reported that brachial plexus avulsion (BPA) results in a marked and long-lasting mechanical hypernociception in rodents. Here we demonstrate that antibodies against NGF, NT-3, GDNF and BDNF were able to postpone the mechanical hypernociception in mice when dosed locally, systemically or intrathecally (i.t.) at the time of surgery. However, none of them were able to interfere with the mechanical hypernociception when administered intraventricularly (i.c.v.) at the moment of surgery or even i.p. on the 4th day after the injury. Interestingly, the anti-BDNF antibody was the only one that substantially reversed the mechanical hypernociceptive state when administered i.t. or i.c.v. on the 4th day after the BPA. We might suggest that NTFs, notably BDNF, are involved in the mechanisms underlying neuropathic pain-like behavior following BPA. These pieces of evidence corroborate the notion that NTF blockers might represent a new and interesting option for the management of neuropathic pain.

Concepts of nerve regeneration and repair applied to brachial plexus reconstruction.

Brachial plexus injury is a serious condition that usually affects young adults. Progress in brachial plexus repair is intimately related to peripheral nerve surgery, and depends on clinical and experimental studies. We review the rat brachial plexus as an experimental model, together with its behavioral evaluation. Techniques to repair nerves, such as neurolysis, nerve coaptation, nerve grafting, nerve transfer, fascicular transfer, direct muscle neurotization, and end-to-side neurorraphy, are discussed in light of the authors' experimental studies. Intradural repair of the brachial plexus by graft implants into the spinal cord and motor rootlet transfer offer new possibilities in brachial plexus reconstruction. The clinical experience of intradural repair is presented. Surgical planning in root rupture or avulsion is proposed. In total avulsion, the authors are in favor of the reconstruction of thoraco-brachial and abdomino-antebrachial grasping, and on the transfer of the brachialis muscle to the wrist extensors if it is reinnervated. Surgical treatment of painful conditions and new drugs are also discussed.

[Influence of temperature on comparative nerve conduction techniques for carpal tunnel syndrome diagnosis].

In this study we compared the effect of temperature variation (> or = 32 degrees C to < or = 27 degrees C) on latency differences median to ulnar (ringdiff), median to radial (thumbdiff), palmar median to ulnar (palmdiff) and the sum of three, the combined sensory index (CSI), in 15 controls and 12 patients with carpal tunnel syndrome (CTS). After cooling, ringdiff was the most reliable technique with little variation in both controls and patients; thumbdiff decreased dramatically in controls and could even come within normal limits in patients; palmdiff increased only in patients; CSI decreased significantly in controls and showed a slight increase in patients with no loss in electrodiagnosis accuracy. The high increase of palmdiff in patients, and the high decrease of thumbdiff in controls, after cooling, could not be explained only for fiber size in the nerve trunks. We concluded that for CTS electrodiagnosis even latency differences in same person/same limb could be significantly modified after cooling not previously emphasized in literature.

Influence of temperature on comparative nerve conduction techniques for carpal tunnel syndrome diagnosis

O objetivo do estudo foi comparar o efeito da variação de temperatura da mão (>32ºC e <27ºC) no estudo das técnicas de diferenças de latências entre o nervo mediano e ulnar (MU4), mediano e radial (MR1), mediano e ulnar palmar (MUP) e índice sensitivo combinado (ISC) em 15 controles normais e 12 pacientes com síndrome do túnel do carpo (STC). Após resfriamento da mão, MU4 foi a técnica mais confiável com menor variação de latência tanto em controles como em pacientes; MR1 diminuiu dramaticamente nos controles e atingiu até valores normais em pacientes; MUP aumentou apenas em pacientes; ISC diminuiu significantemente em controles com leve aumento nos pacientes, porém sem perda da acurácia eletrodiagnóstica. O acentuado aumento de MUP em pacientes e a acentuada redução de MR1 em controles após o resfriamento não pôde ser explicado apenas pelo calibre das fibras nervosas nos diferentes troncos. Concluímos que mesmo quando se utilizam técnicas de comparação de latências entre dois nervos na mesma pessoa e no mesmo segmento, a redução da temperatura pode modificar de maneira significativa os resultados, dado não previamente relatado na literatura.

Relationship between evoked motor response and sensory paresthesia in interscalene brachial plexus block.

BACKGROUND AND OBJECTIVES: This study sought to define the relationship between a paresthesia and a motor response (MR) to electrical nerve stimulation using a peripheral nerve stimulator (PNS) during interscalene block. We sought to determine if at a low amperage (< or =1.0 mA) a MR would precede a paresthesia. METHODS: Twenty-two interscalene blocks were performed using insulated needles and a PNS. A MR was obtained at 0.5 mA and then the PNS was turned off. The needle was further advanced until a paresthesia was elicited. The PNS was again turned on, the needle held immobile, and the amperage increased in 0.1 mA increments up to 0.5 mA, or an MR obtained, whichever occurred first. If no MR was obtained, the needle was withdrawn at 0.5 mA in the same direction as it entered until MR was again observed. RESULTS: A MR was obtained at 0.5 mA in all the patients. After the PNS was turned off and the needle further advanced, a paresthesia was elicited in 21 patients. When the PNS was turned on again, a MR was produced at 0 to 0.5 mA in 13 patients. In a subset of 8 patients without a second MR to stimulation up to 0.5 mA, the needle was withdrawn at that amperage. A MR was subsequently obtained during withdrawal in each patient in this subset. CONCLUSIONS: MR preceded paresthesia in every patient. The most likely explanation for this observation is that MR can be achieved at a small distance from the nerve, whereas elicitation of mechanical paresthesia requires either nerve contact or more intimate location of the needle's tip relative to the nerve. Another possible explanation is that motor fibers are located in a more superficial position and are therefore encountered first. Motor and sensory responses are separate and discrete phenomena.

Reparación quirúrgica de las lesiones supraclaviculares del plexo bronquial C5 C6 C7

Desde 1980 hasta 1994, fueron efectuadas 109 reparaciones directas de parálisis de Erb (C5 C6) asociada o no con daño de C7. El promediode edad en este estudio fue de 35 años, encontrándose la mayoría de los pacientes entre los 16 los 25 años. El tiempo transcurrido desde la lesión hasta la reparción varió desde 1 día hasta 1 año y 6 meses. La reparción quirúrgica se efectuó interponiendo injertos nerviosos entrelas raíces lesionadas y los nervios distales a reparar. Ningún resultado pudo ser calificado como muy bueno. Se obtuvieron buenos y medianos en 62 pacientes (59.6 por ciento). Encontrándose los peores resultados cuando cuando la reparación se hizo tardíamente. Pese a una buena recuperación 43 pacientes cambiaron de trabajo y 25 no volvieron a tener ninguna ocupación