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1.
Medicine (Baltimore) ; 100(12): e24324, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33761632

RESUMO

ABSTRACT: To evaluate the feasibility of utilizing ultrasonography to monitor the fracture reduction and elastic intramedullary nail fixation processes in treating children with double forearm fractures. A retrospective analysis of 30 children with double forearm fractures treated at our hospital between January 2016 and July 2018. The children were aged 3 to 10 years. All patients were treated with closed reduction and internal fixation with elastic intramedullary nails using intraoperative ultrasound monitoring and intermittent radiographic imaging. The closed reduction and fixation were successful in all patients. The operation times ranged from 16 to 30 minutes, averaging 21 minutes. No neurovascular injuries occurred during closed reduction and nail insertion. Moreover, closed reduction was successful in the first attempt in 86.7% of patients. All patient outcomes were optimal, lacking serious complications during follow-ups. Intraoperative ultrasound monitoring can clearly show the shape and changes in fracture ends, distal growth plates, and surrounding soft tissues, and fracture reduction and passage of elastic nail processes at fracture ends during closed reduction; therefore, visualizing closed reductions can be achieved. The combination of intraoperative ultrasound and radiographic imaging can ensure operative effects and significantly reduce radiation exposure for both doctors and patients. An adequately powered prospective randomized trial is required to confirm our findings.


Assuntos
Antebraço/diagnóstico por imagem , Fixação Intramedular de Fraturas/instrumentação , Monitorização Intraoperatória/métodos , Fraturas do Rádio/cirurgia , Fraturas da Ulna/cirurgia , Pinos Ortopédicos , Criança , Pré-Escolar , Redução Fechada , Estudos de Viabilidade , Feminino , Humanos , Masculino , Radiografia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/lesões , Rádio (Anatomia)/cirurgia , Fraturas do Rádio/complicações , Fraturas do Rádio/diagnóstico , Estudos Retrospectivos , Resultado do Tratamento , Ulna/diagnóstico por imagem , Ulna/lesões , Ulna/cirurgia , Fraturas da Ulna/complicações , Fraturas da Ulna/diagnóstico , Ultrassonografia
2.
Sci Data ; 8(1): 47, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547317

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor and non-motor symptoms. Dyskinesia and motor fluctuations are complications of PD medications. An objective measure of on/off time with/without dyskinesia has been sought for some time because it would facilitate the titration of medications. The objective of the dataset herein presented is to assess if wearable sensor data can be used to generate accurate estimates of limb-specific symptom severity. Nineteen subjects with PD experiencing motor fluctuations were asked to wear a total of five wearable sensors on both forearms and shanks, as well as on the lower back. Accelerometer data was collected for four days, including two laboratory visits lasting 3 to 4 hours each while the remainder of the time was spent at home and in the community. During the laboratory visits, subjects performed a battery of motor tasks while clinicians rated limb-specific symptom severity. At home, subjects were instructed to use a smartphone app that guided the periodic performance of a set of motor tasks.


Assuntos
Acelerometria/instrumentação , Monitorização Ambulatorial , Doença de Parkinson/diagnóstico , Dispositivos Eletrônicos Vestíveis , Antebraço , Humanos , Perna (Membro) , Aplicativos Móveis , Doença de Parkinson/fisiopatologia , Smartphone , Tronco
3.
Sci Data ; 8(1): 63, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602931

RESUMO

Control of contemporary, multi-joint prosthetic hands is commonly realized by using electromyographic signals from the muscles remaining after amputation at the forearm level. Although this principle is trying to imitate the natural control structure where muscles control the joints of the hand, in practice, myoelectric control provides only basic hand functions to an amputee using a dexterous prosthesis. This study aims to provide an annotated database of high-density surface electromyographic signals to aid the efforts of designing robust and versatile electromyographic control interfaces for prosthetic hands. The electromyographic signals were recorded using 128 channels within two electrode grids positioned on the forearms of 20 able-bodied volunteers. The participants performed 65 different hand gestures in an isometric manner. The hand movements were strictly timed using an automated recording protocol which also synchronously recorded the electromyographic signals and hand joint forces. To assess the quality of the recorded signals several quantitative assessments were performed, such as frequency content analysis, channel crosstalk, and the detection of poor skin-electrode contacts.


Assuntos
Eletromiografia , Gestos , Mãos/fisiologia , Adulto , Membros Artificiais , Eletrodos , Feminino , Antebraço/fisiologia , Humanos , Contração Isométrica , Masculino , Pessoa de Meia-Idade , Movimento/fisiologia , Músculo Esquelético/fisiologia , Desenho de Prótese
4.
J Hand Surg Asian Pac Vol ; 26(1): 17-23, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33559563

RESUMO

Background: Previous reports on schwannomas of the upper extremities have mainly focused on proximal involvement. This study aimed to evaluate pre- and peri-operative findings in schwannomas of the distal upper extremities and assess the accuracy of diagnosis and surgical outcome. Methods: We identified 24 patients with isolated tumors. Seven patients had schwannomas located in the forearm, eleven in the hand, and six in the digits. We collected the following data: preoperative clinical and magnetic resonance imaging findings, provisional diagnosis, surgical findings and procedures, tumor volume, and postoperative clinical findings. Data were compared between tumors of different locations. Results: The mean age of our cohort at the time of surgery was 48.0 years and the mean follow-up period was 10.6 months. All patients with forearm schwannomas were diagnosed preoperatively by the presence of the Tinel-like sign and suggestive magnetic resonance imaging findings. In contrast, schwannomas in the hands and digits often lacked these diagnostic features; only five patients with hand schwannomas and one with digit schwannoma were correctly diagnosed. Microsurgical enucleation was the most common treatment. Ten patients reported newly acquired paresthesia after operation, which resolved within the follow-up period in nine patients. Three of the four patients with preoperative paresthesia and one patient who underwent enucleation with surgical loupes still had paresthesia at the final follow-up. Conclusions: In schwannomas of the distal upper extremities, a more distal location is associated with a lower occurrence of the Tinel-like sign and fewer suggestive magnetic resonance imaging findings, resulting in lower diagnostic accuracy. However, intra-operative diagnosis is usually straightforward and microsurgical enucleation does not cause iatrogenic nerve deficit. When treating soft tissue tumors in the hand and digits that present without specific or suggestive findings, the possibility of schwannoma should be considered.


Assuntos
Neurilemoma/diagnóstico por imagem , Neurilemoma/cirurgia , Neoplasias do Sistema Nervoso Periférico/diagnóstico por imagem , Neoplasias do Sistema Nervoso Periférico/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Dedos/cirurgia , Seguimentos , Antebraço/cirurgia , Mãos/cirurgia , Humanos , Imagem por Ressonância Magnética , Masculino , Microcirurgia , Pessoa de Meia-Idade , Parestesia/etiologia , Parestesia/cirurgia , Complicações Pós-Operatórias , Estudos Retrospectivos , Adulto Jovem
5.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(2): 149-153, 2021 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-33624465

RESUMO

Objective: To explore the effectiveness of open reduction and internal fixation for bipolar fracture-dislocation of the forearm. Methods: Between June 2014 and March 2019, 14 patients with bipolar fracture-dislocation of the forearm were treated. There were 9 males and 5 females, aged from 19 to 52 years (mean, 34.9 years). There were 8 cases of falling injuries, 4 cases of traffic accident injuries, 1 case of sports injury, and 1 case of machine strangulation injury. The time from injury to admission was 2-48 hours, with an average of 16.6 hours. All patients were closed injuries. All patients were treated with open reduction and internal fixation; the upper radioulnar joints were treated with circumferential ligament repair or lateral collateral ligament repair according to the joint stability. And the patients with lower radioulnar joint instability were also treated with the TightRope plate with loop fixation. After 3 weeks of plaster fixation, the patients started functional exercises. The fracture healing time, stability and range of motion of wrist and elbow joints, and forearm rotation function were recorded. The effectiveness was evaluated by Anderson's forearm function score at last follow-up. Results: The incisions healed by first intention. All 14 cases were followed up 12-36 months with an average of 24.8 months. All fractures healed, with an average healing time of 14.9 weeks (range, 12-18 weeks). The stabilities of the upper and lower radioulnar joints restored well. At last follow-up, the elbow flexion and extension range of motion was 65°-160°, with an average of 124.6°; the wrist flexion and extension range of motion was 115°-165°, with an average of 155.0°; the forearm rotation range of motion was 65°-165°, with an average of 154.6°. According to Anderson's forearm function score, 8 cases were excellent, 5 cases were good, and 1 case was unsatisfactory. Conclusion: The treatment of bipolar fracture-dislocation of the forearm needs comprehensive consideration and individualized treatment plan. The focus is to restore the anatomical structure of the radius and ulna and firm internal fixation, stabilize the upper and lower radioulnar joints, and perform functional exercises as soon as possible after operation to obtain satisfactory effectiveness.


Assuntos
Antebraço , Fixação Interna de Fraturas , Fraturas Ósseas , Adulto , Idoso , Feminino , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Articulação do Punho/cirurgia , Adulto Jovem
6.
Handchir Mikrochir Plast Chir ; 53(1): 19-25, 2021 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-33588488

RESUMO

BACKGROUND: There are no data ensuring a standardized landmark-based-technique for blocking sensitive nerves of the forearm. PURPOSE: To identify locations were with use of good palpable bony landmarks and lines between them sensitive nerve blocks on the forearm can be done with great success. MATERIAL AND METHODS: Dissection of the superficial branch of the radial nerve (SBRN), the dorsal branch of the ulnar nerve (DBUN), the lateral, medial and dorsal antebrachial cutaneous nerve (LACN, MACN, and DACN) as well as the palmar branch of the median nerve (PBMN) was performed on five upper limbs of five different Caucasian cadavers. With respect to radius and ulnar styloid, Lister's tubercle, and the medial and lateral epicondyle of the humerus as well as connecting lines between these bony landmarks locations were defined, where the mentioned nerves can be found and blocked. RESULTS: The six nerves can be safely blocked at the following sites: the SBRN 85 mm proximal to Lister's tubercle on a line drawn between the latter and the medial humeral epicondyle; the LACN 38 mm and the dorsal one 32 mm ulnar from the lateral epicondyle; the MACN 14 mm radial to the medial epicondyle; the DBUN 27 mm proximal to the ulnar styloid in direction to the lateral epicondyle; the PBMN 45 mm proximal to the radial styloid following a line between the latter and the medial epicondyle and 21 mm ulnarwards perpendicular to this line. CONCLUSION: Using superficial good palpable landmarks at the wrist and elbow as well as connecting lines between them the SBRN, DBUN, PBMN, LACN, MACN, and DACN can easily be located.


Assuntos
Antebraço , Punho , Cadáver , Mãos , Humanos , Articulação do Punho
7.
Handchir Mikrochir Plast Chir ; 53(1): 26-30, 2021 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-33588489

RESUMO

BACKGROUND: Decompression of the anterior interosseous nerve can be performed in an open operative exploration or endoscopically. Using an endoscopic decompression superficial anatomical landmarks serve as reference point. The aim of the study was to determine the location of the distribution of the median nerve in relation to the elbow joint in order to facilitate preparation during endoscopic decompression. MATERIALS AND METHODS: The median nerve and the anterior interosseous nerve were dissected in 31 human specimens with regard to the elbow joint. The superficial anatomical landmark was the intercondyle line between the medial and lateral epicondyles. The distance between the origination of the anterior interosseous nerve of the median nerve was measured in relation to the intercondyle line. RESULTS: The anatomical preparation was done using 62 adult cadaveric upper extremities. 11 specimens were formalin fixed and 20 specimens were fresh frozen cadaveric upper extremities. The average of the intercondyle distance was 7.2 cm ± 0.5 (min. 5.8; max. 7.8). The anterior interosseous nerve originated from the median nerve in average 39 mm ± 18 (min. 8; max. 80) distal to the intercondyle line. In 12 cases the distance was within the first 2 cm. There was only a correlation between the length of the upper arm and the nerve junction. CONCLUSION: The anterior interosseous nerve originated from the median nerve in average 4 cm distal to the intercondyle line. Although there was a distribution under 2 cm in around 20 % of the cases. This is very important with regard to the endoscopically technique and should be considered.


Assuntos
Descompressão Cirúrgica , Vértebras Lombares , Adulto , Cadáver , Antebraço , Humanos , Nervo Mediano/cirurgia
8.
BMJ Case Rep ; 14(1)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33495176

RESUMO

Cutaneous larva migrans is an acquired, self-limited infestation caused by cat hookworm, Ancylostoma braziliense, and dog hookworm, A. caninum The disease is acquired by direct contact with contaminated soil. Circumrotation is a religious ritual practised by devotees of Hinduism as a fulfilment of vows taken at the shrine and involves rolling over with uncovered upper body on the sand over a distance of up to 600 m. It is a reported mode of acquisition of cutaneous larva migrans infestation. The authors report a 10-year-old boy who acquired cutaneous larva migrans on his right forearm after circumrotation. The forearm is an unusual site for this infestation, and most reported cases had lesions on the feet, thighs and buttocks following either sitting or playing on contaminated soil. The child made complete recovery following treatment with albendazole for 1 week.


Assuntos
Ancilostomíase/diagnóstico , Antebraço , Larva Migrans/diagnóstico , Albendazol/uso terapêutico , Ancilostomíase/tratamento farmacológico , Anti-Helmínticos/uso terapêutico , Comportamento Ritualístico , Criança , Hinduísmo , Humanos , Larva Migrans/tratamento farmacológico , Masculino
9.
Neuroimage ; 228: 117702, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33385558

RESUMO

The development of the organization of the motor representation areas in children and adolescents is not well-known. This cross-sectional study aimed to provide an understanding for the development of the functional motor areas of the upper extremity muscles by studying healthy right-handed children (6-9 years, n = 10), preadolescents (10-12 years, n = 13), adolescents (15-17 years, n = 12), and adults (22-34 years, n = 12). The optimal representation site and resting motor threshold (rMT) for the abductor pollicis brevis (APB) were assessed in both hemispheres using navigated transcranial magnetic stimulation (nTMS). Motor mapping was performed at 110% of the rMT while recording the EMG of six upper limb muscles in the hand and forearm. The association between the motor map and manual dexterity (box and block test, BBT) was examined. The mapping was well-tolerated and feasible in all but the youngest participant whose rMT exceeded the maximum stimulator output. The centers-of-gravity (CoG) for individual muscles were scattered to the greatest extent in the group of preadolescents and centered and became more focused with age. In preadolescents, the CoGs in the left hemisphere were located more laterally, and they shifted medially with age. The proportion of hand compared to arm representation increased with age (p = 0.001); in the right hemisphere, this was associated with greater fine motor ability. Similarly, there was less overlap between hand and forearm muscles representations in children compared to adults (p<0.001). There was a posterior-anterior shift in the APB hotspot coordinate with age, and the APB coordinate in the left hemisphere exhibited a lateral to medial shift with age from adolescence to adulthood (p = 0.006). Our results contribute to the elucidation of the developmental course in the organization of the motor cortex and its associations with fine motor skills. It was shown that nTMS motor mapping in relaxed muscles is feasible in developmental studies in children older than seven years of age.


Assuntos
Mapeamento Encefálico/métodos , Antebraço/inervação , Mãos/inervação , Córtex Motor/crescimento & desenvolvimento , Músculo Esquelético/inervação , Adolescente , Adulto , Criança , Estudos Transversais , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Estimulação Magnética Transcraniana/métodos , Adulto Jovem
10.
J Med Case Rep ; 15(1): 14, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33461603

RESUMO

BACKGROUND: Leiomyosarcomas are rare malignant tumors which originate from smooth muscle cells and very seldom give rise to intracerebral metastases. Nearly all cases of intracranial metastases stem from leiomyosarcomas of the uterus. We present a 61-year-old Caucasian man who developed multiple intracranial and extracranial metastases from leiomyosarcoma of the right forearm, diagnosed and treated 9 years before the current presentation. CASE PRESENTATION: The Caucasian patient presented to the emergency department due to a progressive hemiparesis on the left side. Magnetic resonance imaging scans of the neurocranium showed multiple intracerebral masses with perifocal edema. One of these was located in the right parietal lobe, corresponding to the hemiparesis. The patient underwent microsurgical complete resection of the parietal mass and was subsequently subjected to further radiotherapy. Histopathological studies revealed metastasis of the former leiomyosarcoma. CONCLUSIONS: Leiomyosarcomas represent a rare entity of mesenchymal tumors. Intracerebral metastasis of these tumors is even less frequent. This case shows the importance of long-term follow-up in patients with leiomyosarcoma.


Assuntos
Neoplasias Encefálicas/secundário , Leiomiossarcoma/secundário , Neoplasias de Tecidos Moles/patologia , Neoplasias da Coluna Vertebral/secundário , Neoplasias Gástricas/secundário , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Irradiação Craniana , Antebraço , Humanos , Avaliação de Estado de Karnofsky , Leiomiossarcoma/complicações , Leiomiossarcoma/diagnóstico por imagem , Leiomiossarcoma/terapia , Imagem por Ressonância Magnética , Masculino , Melena/etiologia , Metastasectomia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Procedimentos Neurocirúrgicos , Paresia/etiologia , Antro Pilórico , Radioterapia , Sacro , Neoplasias de Tecidos Moles/cirurgia , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias Gástricas/complicações , Tela Subcutânea , Fatores de Tempo
11.
Am J Physiol Heart Circ Physiol ; 320(3): H991-H998, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33449848

RESUMO

Aging causes deleterious changes in resting conduit artery shear patterns and reduced blood flow during exercise partially attributable to reduced nitric oxide (NO). Inorganic nitrate increases circulating NO bioavailability and may, therefore, improve age-associated changes in shear rate as well as exercise hyperemia. Ten older adults (age: 67 ± 3 yr) consumed 4.03 mmol nitrate and 0.29 mmol nitrite (active) or devoid of both (placebo) daily for 4 wk in a randomized, double-blinded, crossover fashion. Brachial artery diameter (D) and blood velocity (Vmean) were measured via Doppler ultrasound at rest for the characterization of shear profile as well as during two handgrip exercise trials (4 and 8 kg) for calculation of forearm blood flow (Vmean × cross-sectional area, FBF) and conductance [FBF/mean arterial pressure, forearm vascular conductance (FVC)]. Plasma [nitrate] and [nitrite] increased following active (P < 0.05 for both) but not placebo (P = 0.68 and 0.40, respectively) supplementation. Neither mean nor antegrade shear rate changed following either supplement (beverage-by-time P = 0.14 and 0.21, respectively). Retrograde (-13.4 ± 7.0 to -9.7 ± 6.8·s-1) and oscillatory (0.20 ± 0.08 to 0.15 ± 0.09 A.U., P < 0.05 for both) shear decreased following active, but not placebo (P = 0.81 and 0.70, respectively), supplementation. The FBF response (Δ from rest) to neither 4-kg nor 8-kg trials changed following either supplement (beverage-by-time P = 0.53 and 0.11, respectively). Similarly, no changes were observed in FVC responses to 4-kg or 8-kg trials (beverage-by-time P = 0.23 and 0.07, respectively). These data indicate that inorganic nitrate supplementation improves conduit artery shear profiles, but not exercise hyperemia, in older adults.NEW & NOTEWORTHY We report for the first time, to our knowledge, that 4 wk of inorganic nitrate supplementation attenuates retrograde and oscillatory shear in the brachial artery of older adults. However, this was not associated with greater hyperemic or vasodilatory responses to exercise. In sum, these data highlight favorable changes in shear patterns with aging, which may reduce the risk of atherosclerotic cardiovascular disease.


Assuntos
Beta vulgaris , Artéria Braquial/efeitos dos fármacos , Suplementos Nutricionais , Antebraço/irrigação sanguínea , Sucos de Frutas e Vegetais , Hemodinâmica/efeitos dos fármacos , Nitratos/administração & dosagem , Fatores Etários , Idoso , Velocidade do Fluxo Sanguíneo , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nitratos/sangue , Fluxo Sanguíneo Regional , Fatores de Tempo , Resultado do Tratamento
12.
Medicine (Baltimore) ; 100(2): e24071, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33466166

RESUMO

ABSTRACT: The study included 38 ulnar nerves in 20 healthy subjects. High-resolution ultrasound and Shear wave elastography were used to evaluate the ulnar nerve at the mid forearm. The mean cross-sectional area of the ulnar nerve was 7.1 mm2. The mean shear elastic modulus of the nerve in the short axis was 27.4 kPa. The mean shear elastic modulus of the nerve in long axis was 24.7 kPa. No statistical relation could be noted between elasticity measurements in long and short axes. The ulnar nerve elastic modulus also showed no correlation with CSA neither in the long axis nor short axis. Age, height, weight, and body mass index showed no correlation with the ulnar elastic modulus in short or long axes. The elastic modulus of the ulnar nerve has been determined in healthy subjects and can serve as a reference for future assessment of compressive neuropathies of the ulnar nerve.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Antebraço/diagnóstico por imagem , Antebraço/inervação , Nervo Ulnar/diagnóstico por imagem , Adulto , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
13.
Turk Neurosurg ; 31(1): 107-111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33372256

RESUMO

AIM: To study topography and variability in the origin of anterior interosseous nerve; to identify the branching pattern of the anterior interosseous nerve supplying the flexor digitorum profundus, flexor pollicis longus, and pronator quadratus muscles. MATERIAL AND METHODS: The present study included 70 formalin-fixed upper limbs of adult human cadavers. The origin of the anterior interosseous nerve was categorized into 3 types. The morphometric data obtained in this study were represented as mean± SD and the dimensions were given in millimeter. The measurements were compared statistically by using 'EZR software, version 1.38, 2019'. The 'paired t-test' was applied and the 'p' value less than 0.05 was considered as statistically significant. RESULTS: It was observed that the origin of the anterior interosseous nerve was extremely variable. It was ranging from the midepicondylar point of the elbow joint up to as below as 86mm from it. The distance of its origin from the midpoint of the pronator teres muscle ranged between 70 mm above the pronator teres muscle to 22 mm below it. In one of the forearms, the median nerve supplied the medial two tendons of the FDP, instead of the ulnar nerve. CONCLUSION: The present study provided additional information about the origin, topography, and distribution of the anterior interosseous nerve. The data will provide further insight into the causes of nerve compression syndromes. It will also help in planning the surgical approach into the distal humerus, elbow joint, and proximal ends of radius and ulna, without causing any nerve injury.


Assuntos
Antebraço/anatomia & histologia , Antebraço/inervação , Nervo Mediano/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/inervação , Adulto , Cadáver , Estudos Transversais , Feminino , Antebraço/patologia , Mãos/inervação , Mãos/patologia , Humanos , Masculino , Nervo Mediano/patologia , Músculo Esquelético/patologia , Síndromes de Compressão Nervosa/patologia , Síndromes de Compressão Nervosa/cirurgia
14.
Clin Imaging ; 69: 374-379, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33075596

RESUMO

INTRODUCTION: Mobile wad of Henry (MOH) is a preferred surgical term used to describe the lateral compartment muscles of the forearm consisting of brachioradialis, extensor carpi radialis longus and brevis. The lesions in this compartment are uncommon. In this paper, we describe the largest series of the MOH lesions including their demographics, imaging appearances and importance of surgical anatomy whilst managing MOH lesions via radiological or surgical interventions. METHODS: A retrospective search of oncology database for lesions in MOH at our tertiary orthopaedic oncology institute was performed for the last 12 years (2007-2019) after obtaining institutional review board approval. We further analyse data to obtain further clarity of various neoplasms occurring at this particular anatomical site. RESULTS: We identified 28 patients with MOH lesions with an age range of 8 to 84 years and a male predominance. Imaging-wise, majority of lesions were benign following characteristics of lipomatous tumours, lipomas being the commonest. Other relatively uncommon benign lesions were nodular fasciitis, myositis ossificans and brachioradialis muscle injury; whereas aggressive MOH soft tissue neoplasms included synovial sarcoma and fibrohistiocytoma. CONCLUSION: Although majority of MOH lesions are benign, one needs to be aware of spectrum containing uncommon benign and aggressive MOH lesions. When posed with dilemma, the MOH lesions require multidisciplinary approach with close collaboration of the radiologist, the surgeon and the pathologist to decide further management.


Assuntos
Cotovelo , Antebraço , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Demografia , Antebraço/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Estudos Retrospectivos , Adulto Jovem
16.
PLoS Comput Biol ; 16(12): e1008350, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33326417

RESUMO

Computational models of the musculoskeletal system are scientific tools used to study human movement, quantify the effects of injury and disease, plan surgical interventions, or control realistic high-dimensional articulated prosthetic limbs. If the models are sufficiently accurate, they may embed complex relationships within the sensorimotor system. These potential benefits are limited by the challenge of implementing fast and accurate musculoskeletal computations. A typical hand muscle spans over 3 degrees of freedom (DOF), wrapping over complex geometrical constraints that change its moment arms and lead to complex posture-dependent variation in torque generation. Here, we report a method to accurately and efficiently calculate musculotendon length and moment arms across all physiological postures of the forearm muscles that actuate the hand and wrist. Then, we use this model to test the hypothesis that the functional similarities of muscle actions are embedded in muscle structure. The posture dependent muscle geometry, moment arms and lengths of modeled muscles were captured using autogenerating polynomials that expanded their optimal selection of terms using information measurements. The iterative process approximated 33 musculotendon actuators, each spanning up to 6 DOFs in an 18 DOF model of the human arm and hand, defined over the full physiological range of motion. Using these polynomials, the entire forearm anatomy could be computed in <10 µs, which is far better than what is required for real-time performance, and with low errors in moment arms (below 5%) and lengths (below 0.4%). Moreover, we demonstrate that the number of elements in these autogenerating polynomials does not increase exponentially with increasing muscle complexity; complexity increases linearly instead. Dimensionality reduction using the polynomial terms alone resulted in clusters comprised of muscles with similar functions, indicating the high accuracy of approximating models. We propose that this novel method of describing musculoskeletal biomechanics might further improve the applications of detailed and scalable models to describe human movement.


Assuntos
Biologia Computacional , Fenômenos Fisiológicos Musculoesqueléticos , Fenômenos Biomecânicos , Antebraço/fisiologia , Humanos , Músculo Esquelético/fisiologia
17.
PLoS One ; 15(12): e0227462, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382701

RESUMO

An age-old hypothesis proposes that object motion across the receptor surface organizes sensory maps (Lotze, 19th century). Skin patches learn their relative positions from the order in which they are stimulated during motion events. We propose that reversing the local motion within a global motion sequence ('motion scrambling') provides a good test for this idea, and present results of the first experiment implementing the paradigm. We used 6-point apparent motion along the forearm. In the Scrambled sequence, two middle locations were touched in reversed order (1-2-4-3-5-6, followed by 6-5-3-4-2-1, in a continuous loop). This created a double U-turn within an otherwise constant-velocity motion, as if skin patches 3 and 4 physically swapped locations. The control condition, Orderly, proceeded at constant velocity at inter-stimulus onset interval of 120 ms. The 26.4-minute conditioning (delivered in twenty-four 66-s bouts) was interspersed with testing of perceived motion direction between the two middle tactors presented on their own (sequence 3-4 or 4-3). Our twenty participants reported motion direction. Direction discrimination was degraded following exposure to Scrambled pattern and was 0.31 d' weaker than following Orderly conditioning (p = .007). Consistent with the proposed role of motion, this could be the beginning of re-learning of relative positions. An alternative explanation is that greater speed adaptation occurred in the Scrambled pattern, raising direction threshold. In future studies, longer conditioning should tease apart the two explanations: our re-mapping hypothesis predicts an overall reversal in perceived motion direction between critical locations (for either motion direction), whereas the speed adaptation alternative predicts chance-level performance at worst, without reversing.


Assuntos
Adaptação Fisiológica , Condicionamento Psicológico , Percepção de Movimento/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Adolescente , Adulto , Fenômenos Biomecânicos/fisiologia , Feminino , Antebraço/inervação , Antebraço/fisiologia , Humanos , Masculino , Movimento (Física) , Psicofísica/métodos , Pele/inervação , Fenômenos Fisiológicos da Pele
18.
BMJ Case Rep ; 13(12)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33372013

RESUMO

In this article, we intend to discuss a case of cutaneous myiasis in a British child traveller who recently travelled to Somaliland. A Cordylobia anthropophaga larva was identified as the species that caused the disease. The case report, which contains a video illustration of the causative agent, proved a diagnostic challenge at presentation.


Assuntos
Antebraço/parasitologia , Miíase/diagnóstico , Dor/parasitologia , Doença Relacionada a Viagens , Animais , Pré-Escolar , Tratamento Conservador , Diagnóstico Diferencial , Dípteros , Djibuti , Feminino , Humanos , Miíase/terapia
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 722-727, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018089

RESUMO

Electromyography offers a way to interface an amputee's resilient muscles to control a bionic prosthesis. While myoelectric prostheses are promising, user acceptance of these devices remain low due to a lack of intuitiveness and ease-of-use. Using a low-cost wearable flexible electrodes array, the proposed system leverages high-density surface electromyography (HD-EMG) and deep learning techniques to classify forearm muscle contractions. These techniques allow for increased intuitiveness and ease-of-use of a myoelectric control scheme with a single easy-to-install electrodes apparatus. This paper proposes a flexible electrodes array construction using standard printed circuit board manufacturing processes for low-cost and quick design-to-production cycles. HD-EMG dataset visualization with t-distributed Stochastic Neighbor Embedding (t-SNE) is introduced, and offline classification results of the wearable gesture recognition system for hand prosthesis control are validated on a group of 8 able-bodied subjects. Using a majority vote on 5 successive inferences, a median recognition accuracy of 98.61 % was obtained across the group for an 8 gestures set. For a 6 gestures set containing commonly used prosthesis positions, the median accuracy reached 99.57 % with the majority vote.


Assuntos
Visualização de Dados , Antebraço , Eletromiografia , Mãos , Humanos , Aprendizado de Máquina
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3134-3137, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018669

RESUMO

Numerous applications in areas such as ergonomics assessment, clinical biomechanics and motor control research would benefit from accurately modeling the relationship between forearm EMG and fingertip force, using conventional electrodes. Herein, we describe a methodological study of relating 12 conventional surface EMGs, applied circumferentially about the forearm, to fingertip force during constant-pose, force-varying (dynamic) contractions. We studied independent contraction of one, two, three or four fingers (thumb excluded), as well as contraction of four fingers in unison. Using regression, we found that a pseudo-inverse tolerance (ratio of largest to smallest singular value) of 0.01 was optimal. Lower values produced erratic models and higher values produced models with higher errors. EMG-force errors using one finger ranged from 2.5-3.8% maximum voluntary contraction (MVC), using the optimal pseudo-inverse tolerance. With additional fingers (two, three or four), the average error ranged from 5-8 %MVC. When four fingers contracted in unison, the average error was 4.3 %MVC.


Assuntos
Dedos , Antebraço , Eletromiografia , Ergonomia , Humanos , Polegar
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