Sonographic Evaluation of Superficial Peroneal Nerve Abnormalities.

OBJECTIVE: The objective of this study was to review the anatomy of the superficial peroneal nerve (SPN) and describe the sonographic appearances of various abnormalities affecting it. We performed a retrospective chart review of ultrasound (US) examinations of the SPN performed from 2014 to 2016. CONCLUSION: SPN abnormalities are well shown on US. Of 181 patients examined with US, the most commonly detected abnormality was scar encasement and neuroma or laceration.

Ultrasound to depict anatomical abnormality: an example of potential alliance of rehabilitation professionals.

.

The developmental and genetic basis of 'clubfoot' in the peroneal muscular atrophy mutant mouse.

Genetic factors underlying the human limb abnormality congenital talipes equinovarus ('clubfoot') remain incompletely understood. The spontaneous autosomal recessive mouse 'peroneal muscular atrophy' mutant (PMA) is a faithful morphological model of human clubfoot. In PMA mice, the dorsal (peroneal) branches of the sciatic nerves are absent. In this study, the primary developmental defect was identified as a reduced growth of sciatic nerve lateral motor column (LMC) neurons leading to failure to project to dorsal (peroneal) lower limb muscle blocks. The pma mutation was mapped and a candidate gene encoding LIM-domain kinase 1 (Limk1) identified, which is upregulated in mutant lateral LMC motor neurons. Genetic and molecular analyses showed that the mutation acts in the EphA4-Limk1-Cfl1/cofilin-actin pathway to modulate growth cone extension/collapse. In the chicken, both experimental upregulation of Limk1 by electroporation and pharmacological inhibition of actin turnover led to defects in hindlimb spinal motor neuron growth and pathfinding, and mimicked the clubfoot phenotype. The data support a neuromuscular aetiology for clubfoot and provide a mechanistic framework to understand clubfoot in humans.

Anatomical variation of sciatic nerve: a case report of high division and unusual anastomosis with the posterior femoral cutaneous nerve

The posterior femoral cutaneous nerve is a sensitive nerve that rises from S1-S3, usually giving off cutaneous branches for the gluteal region, perineum, the posterior region of the thigh and leg. The sciatic nerve is the largest nerve in the human body, rising from L4-S3, and divides into the tibial and common fibular nerves, innervating the muscles from the posterior compartment of the thigh. Anastomosis between the sciatic nerve and the posterior femoral cutaneous nerve is rare. During dissection of the right gluteal region on a male cadaver fixed with 10% formalin, we observed an anastomosis between both nerves, while the common fibular nerve perforated the piriformis muscle, dividing it in two muscle slips. Both nerves trajectories were within the regular pattern after this communication. Our aims were to describe this unusual case of anastomosis and perform a literature review on the variations of the sciatic nerve, while also discussing their clinical significance

No disponible

Prevalence of the accessory deep peroneal nerve: A cadaveric study and meta-analysis.

OBJECTIVES: The accessory deep peroneal nerve (ADPN) is a common anatomical variant arising from the superficial peroneal nerve (SPN) and, when present, is often responsible for partial or complete innervation of the extensor digitorum brevis muscle (EDBM). The nerve lies posterior to the peroneus brevis muscle, traveling posterior to the lateral malleolus to terminate in the ankle by giving off sensory branches to the ankle and joints. Although the EDBM is usually supplied by the deep peroneal nerve (DPN), in the presence of an ADPN, electrodiagnostic procedures may be complicated. Due to the lack of detailed anatomical knowledge on the topography of the ADPN, its presence posterior to the lateral malleolus can be iatrogenically injured during surgical procedures on the ankle using a lateral approach. Therefore, this meta-analysis aimed to provide a comprehensive, evidence-based assessment of the anatomical characteristics of the ADPN, supplemented with data from our own cadaveric dissection. PATIENTS AND METHODS: A comprehensive search of all major electronic databases, including Pubmed, Embase, Scopus, Web of Science, ScienceDirect, SciELO, and BIOSIS was performed. All articles with data on prevalence, symmetry and innervation of the EDBM by the ADPN were included. The anatomical data was then extracted and pooled into a meta-analysis using MetaXL 2.0. In addition, we dissected 21 cadavers (n=42 lower limbs) bilaterally to find the ADPN. RESULTS: A total of 19 studies (n=6070 lower limbs) were included in the meta-analysis. The pooled prevalence of the ADPN was 18.8% (95%CI:14.2-24.0) with a 39.3% prevalence rate for cadaveric studies. The ADPN was present more commonly unilaterally (67.0%) and when it was present, provided branches to the EDBM in 79.5% of cases. In our cadaveric study, the ADPN was identified in 5 of the 42 lower limbs dissected (11.9%); on the right side in 3 lower limbs and on the left side in 2 lower limbs. CONCLUSIONS: The ADPN is a clinically important nerve and has been inculpated in unexplained cases of chronic ankle pain and EDBM atrophy. The variability in detection of the ADPN using electrophysiological techniques can lead to misdiagnoses of peroneal nerve lesions and increase the risk for iatrogenic injury to the ADPN, especially in laterally approaching ankle procedures and sural nerve biopsies.

Efeitos da irradiação com laser de baixa potência nas glândulas salivares submandibulares de ratas diabéticas induzidas por estreptozotocina / Low-power laser irradiation effects in submandibular glands of streptozotocin-induced diabetic rats

O diabetes mellitus (DM) pode levar à disfunção das glândulas salivares. A ativação do receptor de produtos finais de glicosilação avançada e de seus ligantes tem sido reportado em várias doenças crônicas, entre estas, a diabetes e suas complicações. Este estudo analisou a expressão do RAGE, proteína do grupo de alta mobilidade B1 (HMGB1) e de produtos de glicosilação avançada (AGE), bem como os efeitos da irradiação com laser de baixa potência (ILBP) em glândulas salivares submandibulares (GSMs) de ratas diabéticas. Ratas Wistar com 12 semanas de vida foram divididas em 3 grupos: controle (C), diabético (D) e diabético com laser (DL). A indução de DM nos grupos D e DL foi realizada com injeção intraperitoneal de estreptozotocina 60 mg/kg de peso corporal, no 1° dia experimental. No 29°dia, os animais do grupo DL receberam a ILBP (660 nm, 70 mW, 20 J/cm² e 0,56 J por ponto), aplicado no total de quarenta pontos cobrindo a área correspondente as GSMs, e os seus efeitos foram avaliados 24 h após a irradiação (eutanásia). As análises de parâmetros metabólicos, histológicos e de marcadores de inflamação, apoptose e proliferação foram realizadas. Nossos achados mostram que a ILBP diminuiu a glicemia das ratas diabéticas irradiadas, melhorando a resistência à insulina (HOMA-IR), sensibilidade à insulina (HOMA-IS) e função de células beta (HOMA-?). Em GSM, o DM parece aumentar a expressão do eixo HMGB1/AGE/RAGE, possivelmente associado à ativação do fator de transcrição nuclear kappa B (NF?B). A ILBP reduziu os marcadores de inflamação, HMGB1 e TNF-? em GSM de ratas diabéticas, e parece regular a expressão de proteínas relacionadas à proliferação e à apoptose, pela via do AMP cíclico, parcialmente mediado por proteína kinase regulada por sinais extracelulares. No entanto, mais estudos são necessários para melhor entender os efeitos do laser neste tecido.

Diabetes (DM) can lead to dysfunction of the secretory capacity in salivary glands. Since the activation of the receptor for advanced glycation end-products (RAGE) and its ligands has been suggested to participate in chronic disorders, such as diabetes and its complications. This study analyzed the expression of RAGE, high mobility group box protein B1 (HMGB1) and advanced glycation end-products (AGEs) were evaluated, as well as the effects of low-power laser irradiation (ILBP), in diabetic submandibular glands (GSM). Wistar rats 12 weeks-old were divided in three groups: control (C), diabetic (D) and diabetic with laser (DL). The D and DL rats were intraperitoneally injected with streptozotocin 60 mg/kg, in the 1st experimental day. On the 29° day, the DL rats received the ILBP (660 nm, 70 mW, 20 J/cm² e 0,56J per point), with a total of forty points covering the GSMs area, its effects were evaluated 24h after irradiation (euthanasia). Metabolic parameters, histology and the inflammatory, apoptosis and proliferation markers were evaluated. Our findings show that ILBP reduced the blood glucose levels of the irradiated diabetic rats, improving their insulin resistance (HOMA-IR), insulin sensitivity (HOMA-IS) e beta cell function (HOMA-?). In GSM, DM seems to upregulate the expression of HMGB1/AGE/RAGE axis, possibly associated with the activation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF?B). The ILBP reduced the inflammatory markers HMGB1 and TNF-? in diabetic GSM, and seems to regulate the expression of proteins related to proliferation and apoptosis, by cyclic AMP pathway, partially mediated by extracellular signal-regulated kinase. However, more studies are necessary to better understand the laser effects on this tissue.

Anatomical variations of the formation and course of the sural nerve: A systematic review and meta-analysis.

INTRODUCTION: The sural nerve (SN) is a sensory nerve in the lower extremity which branches to supply the skin on the distal posterolateral third of the lower limb. Typically, the medial sural cutaneous nerve (MSCN) and the peroneal communicating nerve (PCN) unite to form the SN. Other variations in the formation, course, and morphometry of the SN have also been described in the literature. OBJECTIVE: To study anatomical variations in the formation and course of the SN and establish a new classification system for formation patterns of the SN. METHODS: A systematic search of all major databases identified articles that studied the prevalence of variations in the formation of the SN. No date or language restrictions were set. Anatomical data was extracted according to our new classification system where the SN is formed by: union of the MSCN and the PCN (Type 1); union of the MSCN and the Lateral Sural Cutaneous Nerve (LSCN) (Type 2); continuation of the MSCN with absent PCN (Type 3); the PCN alone (Type 4); the LSCN (Type 5); or the Sciatic Nerve (SCN) directly (Type 6). Pooled prevalence rates were calculated using MetaXL 2.0. RESULTS: A total of 39 studies (n=3974 limbs) were included in the meta-analysis. The most common patterns were Type 1, Type 3, and Type 2 with a pooled prevalence of 51.5% (95% CI: 0.293-0.591), 31.2% (95% CI: 0.143-0.410), and 13.8% (95% CI: 0.035-0.234), respectively. The rest of the patterns were rare, with pooled prevalence of Types 4, 5, and 6 calculated to be 1.8% (95% CI: 0-0.063), 1.1% (95% CI: 0-0.050), and 0.7% (95% CI: 0-0.041), respectively. In 83.7% (95% CI: 0.765-0.899) of limbs, the site of union was in the lower half of the lower extremity. The pooled mean length of the SN from the formation to the lateral malleolus was 14.78 (±5.76) cm, while the mean diameter of the SN was 0.28 (±0.03) cm. CONCLUSIONS: Anatomical variations in the formation and course of the SN are common in the population. Clinicians, especially surgeons, should be aware of these variations to avoid iatrogenic injury to the nerve during operative procedures.

[Rare anatomical variation of absence of the sciatic nerve: completely substituted by the tibial and common fibular nerve]. / Variação anatómica rara de ausência do nervo ciático: completamente substituído pelos nervos tibial e fibular comum.

INTRODUCTION: There are several reports of sciatic nerve anatomical variations. Some are associated with clinical entities, such as piriformis syndrome. We aim to report a rare anatomical variation of this nerve. CASES REPORT: Two leucodermic, 74 and 78-year-old male subjects, deceased of natural causes, without lower limb relevant medical history. In both subjects, the right sciatic nerve was absent, with an independent origin and course of the tibial and common fibular nerves. The contralateral sciatic nerve had the common anatomical presentation. DISCUSSION: After the analysis of the available data indexed in Medline, we conclude that we are reporting two cases of a rare anatomical variation (the absence of sciatic nerve, with an independent origin and course of the tibial and common fibular nerve). This anatomical variation may have clinical importance, as it may be, for example, a risk factor to unsuccessful sciatic nerve popliteal blocks and to the pyriformis syndrome.

Introdução: Existem várias publicações referindo variantes anatómicas do nervo ciático, algumas associadas a síndromes clínicos (como sendo a síndrome do músculo piriforme). Neste contexto, pretendemos apresentar uma variante anatómica rara do nervo ciático.Casos clínicos: Dois cadáveres leucodérmicos, masculinos, com 74 e 78 anos, falecidos de morte natural, sem patologia do membro inferior. Em ambos os casos, observou-se ausência do nervo ciático direito, tendo os nervos tibial e fibular comum origem e trajecto independentes, desde a sua origem nas raízes lombo-sagradas até à região poplítea. O nervo ciático contralateral apresentava a anatomia habitual.Discussão: Analisando a literatura, na Medline, realçamos que apresentamos dois casos raros de ausência do nervo ciático, com origem e trajecto independentes dos nervos tibial e fibular comum. Esta variante poderá ter implicações clínicas, nomeadamente ser um factor de risco para o insucesso de bloqueios anestésicos poplíteos e para a síndrome do músculo piriforme.

The accessory deep peroneal nerve and anterior tarsal tunnel syndrome: case report.

The accessory deep peroneal (ADPN) nerve has been regarded as an anomalous nerve derived from the superficial peroneal nerve or its branch and supplies motor innervations for extensor digitorum brevis (EDB) and sensory innervations for the lateral part of the ankle and foot regions. The EDB is usually innervated exclusively by the deep peroneal nerve, a major branch of the the common peroneal nerve, however, in as many as 28% of patients (with same male/female frequency), one or both of the EDB muscles are (partially or exclusively) innervated by the ADPN nerve. This anomaly appears to be inherited in autosomal dominant fashion with incomplete gene penetrance. ADPN existence is of great clinical and surgical importance, and the aim of this study is to describe a very rare case of coexistence ADPN and anterior tarsal tunnel syndrome.

Unique distribution by the peroneal nerves: a case report.

PURPOSE: Among the branches of common peroneal nerve, the superficial peroneal provides cutaneous innervation to major part of the dorsum of the foot and deep peroneal nerve supplies the skin over the first interdigital cleft region. METHODS: The present rare case was observed during routine dissection of leg for undergraduate students, in a 52-year-old male, formalin fixed cadaver. RESULTS: The superficial peroneal nerve provided solely motor branches to peroneus longus and brevis, whereas cutaneous branches were provided by deep peroneal nerve. In the lower one-third of the leg deep peroneal nerve divided into medial and lateral branches. The medial branch supplied tibialis anterior and the lateral branch supplied skin of medial three and half toes. Moreover, the sural nerve supplied the skin of lateral one and a half toes. CONCLUSION: Awareness of this type of variations in the course of nerves helps to alert the surgeons when there are complaints of atypical or unique pain in that particular region.

Función dinámica de los músculos peroneus en apoyo unipodal / Dynamic function of fibular muscles during the unipodal support stage

Los autores hacen una descripción, adentrándose en la fisiología articular, del movimiento de las articulaciones del pie en general y del tobillo en particular. Analizan la acción de los dos músculos retromaleolares, peroneo lateral largo (PLL) y peroneo lateral corto (PLC) cuando el pie está apoyado en el suelo durante el movimiento lineal, marcha y carrera. Describen las ventajas mecánicas que propicia la ubicación, trayecto e inserción de ambos músculos para facilitar el movimiento, tanto en la fase de apoyo unipodal, como en la fase de impulso. Para concluir afirman que es la acción en carga del pie la que ha solicitado de todas las modificaciones mecánicas necesarias, en el complejo articular del tobillo, para economizar al máximo el gasto energético, utilizando como ejemplo la acción de los músculos PLL y PLC (AU)

The authors carry out a description of foot joints movement and more particularly of the ankle joint one, taking into account the joint physiology. They analyse the action of retromalleolar muscles, peroneus longus (PLL) and peroneus brevis (PLC), during the unipodal phase of linear movement (running and walking). The mechanical advantage in the movement as result of location, trajectory and insertion of muscles are described for both the unipodal support and impulse phases. In order to conclude, the writers argue that mechanical modifications of ankle joint during the human evolution process have been conditioned by the foot load force and energy consumption reduction principle. They use as example PLL and PLC muscles (AU)

Ultrasound diagnosis of peroneal nerve variant in a child with compressive mononeuropathy.

We report on a 6-year-old child presenting with subacute foot drop. Neurophysiologic and radiologic studies revealed a peroneal nerve compression secondary to fibular exostosis. Before undergoing surgical removal of the exostosis, the patient underwent further neurophysiologic and ultrasonographic evaluation that showed the presence of an accessory peroneal nerve branch that caused gastrocnemius involvement. Findings at surgery confirmed the supposed anatomical variant. Both nerve components were carefully preserved during the operative procedure. The association of ultrasonographic and neurophysiologic studies was crucial in identifying the etiopathologic mechanism and anatomical picture and provided clinicians and surgeons with important information in planning the procedure.

The drop toe sign: an indicator of neurologic impairment in congenital clubfoot.

UNLABELLED: Nine patients presenting during infancy were identified with clubfeet and absent anterior and lateral compartment functions. We considered these to be neurogenic clubfeet. All patients had the drop toe sign: resting posture of the toes in plantarflexion and absent active dorsiflexion movement after plantar stimulation of the foot. Two patients (three feet) underwent exploration of the peroneal nerve, which revealed anatomic abnormalities. Six patients required more casts than typical for initial correction of deformity; all but two had Achilles tenotomy. Four relapsed despite full-time bracing and eventually needed intraarticular surgery to achieve a plantigrade foot. Idiopathic absent peroneal nerve function is not a well-described entity in the clubfoot literature. All babies with clubfoot should be examined for the drop toe sign. When noted, the feet will likely be more difficult to correct initially, may need early Achilles tendon lengthening, will likely need permanent bracing, are likely to relapse and need intraarticular surgery, and may need multiple surgeries to remain plantigrade throughout growth. LEVEL OF EVIDENCE: Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Lesion of the common peroneal nerve during arthroscopy.

Arthroscopic knee surgery has been well accepted worldwide and has become an important part of orthopaedic surgery. The use of arthroscopy has reduced the duration of hospitalization, overall costs, and time required for the patient to return to sports activities or work. However, because of the closed nature of the procedure and proximity of neurovascular structures to instruments, substantial risk of injuries exists. Significant anatomic variability in the nerve course has not been reported in previous literature as a cause of a knee arthroscopy complication. We present a case of complete transection of an unusually located common peroneal nerve during a knee arthroscopy for lateral meniscal repair in a 22-year-old football player.