Comparison of different analysis techniques for the determination of muscle onset in individuals with patellofemoral pain syndrome

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Myofascial Pain Syndrome as a Contributing Factor in Patients with Chronic Headaches

Objectives: The purpose of this study was to evaluate the prevalence of active and latent trigger points [TrPs], as well as analyze the prevalence of different types of headaches in chronic headache patients. The active and latent TrPs in muscles of orofacial and cervical regions were also evaluated. Methods: There were 290 subjects who participated in this study. Trigger points were identified according to Simons et al.'s diagnostic criteria. Trigger points were considered active if subjects recognized the evoked referred pain as their familiar headache. If the evoked referred pain was not recognized as the familiar headache, the TrPs were considered latent. Differential diagnosis for headache was performed on the basis of International Headache Society criteria. Results: Trigger points could be diagnosed in 77 percent of patients and, in 89 percent of these, active TrPs were found. Muscle tenderness could be observed in 22 percent of patients, and only 1 percent patients were muscle-pain-free. The headache diagnosis showed that 26 percent had tension-type headache, 13 percent had migraine, and 61 percent had combined episodes of tension-type headache and migraine. The highest number of TrPs were found in temporalis [N = 159], masseter [N = 126], and occiptofrontalis [N = 113] muscles. Active TrPs were more frequent in temporalis and occiptofrontalis muscles. Conclusions: Subjects with chronic headaches had a higher prevalence of TrPs, and headache complaints could be reproduced during stimulation of active TrPs that were localized more frequently in temporalis and occiptofrontalis muscles. The presence of TrPs may be a contributing factor in the initiation and/or perpetuation of chronic headaches.

Patellofemoral pain syndrome: Electromyography in a frequency domain analysis

The Patellofemoral Pain Syndrome (PFPS), has a multifactorial etiology and affects approximately 7 to 15% of the population, mostly women, youth, adults and active persons. PFPS causes anterior or retropatelar pain that is exacerbated during functional motor gestures, such as up and down stairs or spending long periods of time sitting, squatting or kneeling. As the diagnostic evaluation of this syndrome is still indirect, different mechanisms and methodologies try to make a classification that distinguishes patients with PFPS in relation to asymptomatic. Thereby, the purpose of this investigation was to determine the characteristics of the electromyographic (EMG) signal in the frequency domain of the vastus medialis oblique (VMO) and vastus lateralis (VL) in patients with PFPS, during the ascent of stairs. 33 young women (22 control group and 11 PFPS group), were evaluated by EMG during ascent of stairs. The VMO mean power frequency (MPF) and the VL frequency 95% (F95) were lower in symptomatic individuals. This may be related to the difference in muscle recruitment strategy exerted by each muscle in the PFPS group compared to the control group.

Characterization of the patellofemoral pain syndrome by frequency parameters of EMG signal

Patellofemoral pain syndrome (PFPS) is the most frequent complaint in orthopedic clinics; although, its etiology remains unclear [Bolgla, 2010; Felicio, 2011]. Trying to understand its causes has been used time analysis of electromyography (EMG), but this method shows controversies. The aim of this study was to apply a method of processing the EMG signal in the frequency domain of the vastus lateralis (VL) and vastus medialis (VM) muscles for the characterization of PFPS.

Diagnostic accuracy of the EMG parameters associated with anterior knee pain in the diagnosis of patellofemoral pain syndrome

Objective To assess the diagnostic accuracy of the surface electromyography (sEMG) parameters associated with referred anterior knee pain in diagnosing patellofemoral pain syndrome (PFPS). Design Sensitivity and specificity analysis. Setting Physical rehabilitation center and laboratory of biomechanics and motor control. Participants Pain-free subjects (n=29) and participants with PFPS (n=22) selected by convenience. Interventions Not applicable. Main Outcome Measure The diagnostic accuracy was calculated for sEMG parameters’ reliability, precision, and ability to differentiate participants with and without PFPS. The selected sEMG parameter associated with anterior knee pain was considered as an index test and was compared with the reference standard for the diagnosis of PFPS. Intraclass correlation coefficient, SEM, independent t tests, sensitivity, specificity, negative and positive likelihood ratios, and negative and positive predictive values were used for the statistical analysis. Results The medium-frequency band (B2) parameter was reliable (intraclass correlation coefficient=.80–.90), precise (SEM=2.71–3.87 normalized unit), and able to differentiate participants with and without PFPS (P<.05). The association of B2 with anterior knee pain showed positive diagnostic accuracy values (specificity, .87; sensitivity, .70; negative likelihood ratio, .33; positive likelihood ratio, 5.63; negative predictive value, .72; and positive predictive value, .86). Conclusions The results provide evidence to support the use of EMG signals (B2 – frequency band of 45–96Hz) of the vastus lateralis and vastus medialis muscles with referred anterior knee pain in the diagnosis of PFPS.

Citral: A monoterpene with prophylactic and therapeutic anti-nociceptive effects in experimental models of acute and chronic pain

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Onset of quadriceps and torque variation in individuals with patellofemoral pain during stair ascent

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos da eletroestimulação do músculo vasto medial oblíquo em portadores de síndrome da dor patelofemoral: uma análise eletromiográfica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Effects of Subarachnoid Administration of Preservative-Free S(+)-Ketamine on Spinal Cord and Meninges in Dogs

BACKGROUND: The N-methyl-D-aspartate receptor antagonist ketamine and its active enantiomer, S(+)-ketamine, have been injected in the epidural and subarachnoid spaces to treat acute postoperative pain and relieve neuropathic pain syndrome. In this study we evaluated the effects of a single dose of preservative-free S(+)-ketamine, in doses usually used in clinical practice, in the spinal cord and meninges of dogs.METHODS: Under anesthesia (IV etomidate (2 mg/kg) and fentanyl (0.005 mg/kg), 16 dogs (6 to 15 kg) were randomized to receive a lumbar intrathecal injection (L5/6) of saline solution of 0.9% (control group) or S(+)-ketamine 1 mg/kg(-1) (ketamine group). All doses were administered in a volume of 1 mL over a 10-second interval. Accordingly, injection solution ranged from 0.6% to 1.5%. After 21 days of clinical observation, the animals were killed; spinal cord, cauda equine root, and meninges were removed for histological examination with light microscopy. Tissues were examined for demyelination (Masson trichrome), neuronal death (hematoxylin and eosin) and astrocyte activation (glial fibrillary acidic protein).RESULTS: No clinical or histological alterations of spinal tissue or meninges were found in animals from either control or ketamine groups.CONCLUSION: A single intrathecal injection of preservative-free S(+)-ketamine, at 1 mg/kg-1 dosage, over a concentration range of 6 to 15 mg/mL injected in the subarachnoid space in a single puncture, did not produce histological alterations in this experimental model. (Anesth Analg 2012;114:450-55)

Síndrome dolorosa complexa regional: epidemiologia, fisiopatologia, manifestações clínicas, testes diagnósticos e propostas terapêuticas

JUSTIFICATIVA E OBJETIVOS: A Síndrome Dolorosa Complexa Regional (SDCR), assim denominada a partir de 1994 pelo Consenso da Associação Internacional para o Estudo da Dor (AIED) e anteriormente denominada de várias formas, tais como Distrofia Simpático Reflexa, Causalgia, Algodistrofia ou Atrofia de Sudeck, é uma doença cuja compreensão dos limites clínicos, fisiopatologia e implicações de patogenia ainda é pobre. Disto resulta a enorme insatisfação não só para os pacientes como para os profissionais da saúde quanto aos métodos terapêuticos atualmente disponíveis. O objetivo deste trabalho é rever a literatura e atualizar um conjunto de informações com o intuito da melhor compreensão desta importante síndrome dolorosa. CONTEÚDO: Este é um trabalho de revisão da literatura nos diversos aspectos da SDCR, com ênfase em suas causas, definição e taxonomia, fisiopatologia, características clínicas, testes diagnósticos e propostas de tratamentos mais recentes. CONCLUSÕES: Poucos são os estudos controlados adequadamente, encobertos e aleatórios, publicados com grandes amostras, havendo muitas dúvidas sobre esta doença. Desta forma, ainda há enorme empirismo na sua terapêutica, e os resultados obtidos são insatisfatórios.

Tempo de início da atividade elétrica dos estabilizadores patelares na marcha em sujeitos com e sem síndrome de dor femoropatelar

INTRODUÇÃO: A síndrome de dor femoropatelar (SDFP) é um problema comum que afeta uma em cada quatro pessoas. A alteração no tempo de ativação e a intensidade de contração dos músculos vasto medial oblíquo (VMO) e vasto lateral (VL) são consideradas fatores importantes na etiologia da SDFP. No entanto, existem poucos estudos sobre a função da porção oblíqua do vasto lateral (VLO) e nenhum sobre o tempo de ativação (onset) do VLO em atividades funcionais em sujeitos normais e com SDFP. OBJETIVO: Assim, o objetivo do estudo foi investigar o tempo de início de atividade eletromiográfica nos músculos VMO, VLO e VL longo (VLL) durante a marcha. MATERIAIS E MÉTODOS: A amostra foi formada por 15 sujeitos sem e 12 com SDFP. Dados eletromiográficos foram obtidos dos músculos VMO, VLL e VLO durante caminhada na esteira sem inclinação. A diferença relativa no onset (DRO) entre VMO-VLL e VMO-VLO foi determinada a partir da média de três passadas. RESULTADOS: Houve diferença entre os sujeitos com e sem SDFP em relação à DRO entre VMO-VLL. Nos sujeitos com SDFP, a ordem de início da atividade elétrica foi VLL seguida por VLO e após VMO. Nos indivíduos sem a patologia, a ordem foi diferente: primeiro VMO após VLO e, por último, VLL. CONCLUSÃO: Os achados sugerem que a ativação do VMO após o VLL poderia auxiliar no desenvolvimento e na manutenção da SDFP, enquanto o tempo de ativação do VLO possui menor participação.

Lesão esportiva: Um estudo sobre a síndrome dolorosa femoropatelar

The patellofemoral pain syndrome (PFPS) is defined as a retropatellar or anterior knee pain, without another disease. It affects until 25% of the population, being more common in women and trained persons. As others pathologies, PFPS have been affected the training of elite and amateurs athletes. Thereby, the general purpose of this study was discuss the occurrence of PFPS as a sports injury, there prevention possibilities and the appropriate recovery training after injury. It had been developed a literature review addressing the specific characteristics of the syndrome, its diagnosis, its target population, its development, how it affects the training and which are their possibilities of prevention and treatment. © FTCD/FIP-MOC.