Effects of Russian current and low-frequency pulsed current on discomfort level and current amplitude at 10% maximal knee extensor torque.

BACKGROUND: Low-frequency pulsed current (LFPC) and Russian current (RC), a type of kilohertz-frequency alternating current, have been frequently used for muscle strengthening in rehabilitation programs. Despite the popularity of these current types, it is unclear which is most effectively able to generate a similar submaximal torque with minimal discomfort and current amplitude. OBJECTIVE: To compare discomfort and current amplitude between LFPC and RC to achieve a knee extensor torque of 10% of the maximal isometric voluntary contraction (MIVC). METHODS: Twenty-two healthy subjects were subjected to three electrically elicited knee extensor submaximal contractions (10% MIVC) that were sustained for 10 seconds. The current amplitude required to achieve 10% MIVC and subjective discomfort were assessed directly by the electrical stimulator and with the Visual Analogue Pain Scale, respectively. A paired t-test was used to determine differences between the electrical currents (α = 0.05). RESULTS: LFPC required significantly lower current amplitude (15%) and a lower discomfort level (50%) to achieve 10% of MIVC compared to RC. CONCLUSION: LFPC current seems to be more effective than RC with respect to discomfort level and current amplitude to produce 10% of MIVC.

Complicações neonatais do diabetes mellitus gestacional ­ DMG / Neonatal complications of gestacional diabetes mellitus ­ GDM

O diabetes mellitus gestacional (DMG) está associado a um risco aumentado de complicações fetais, neonatais e no desenvolvimento a longo prazo. As taxas de aborto espontâneo, natimorto, mal formações congênitas e morbidade e mortalidade perinatal são maiores em filhos de mães diabéticas. As principais complicações neonatais são: macrossomia, hipoglicemia neonatal, deficiência de ferro, alterações da função cardiorrespiratória, hiperbilirrubinemia, anormalidades neurológicas, hipocalcemia, hipomagnesemia e policitemia. A macrossomia predispõe a lesões do parto, especialmente distócia de ombro, maior risco de lesão do plexo braquial, fraturas de clavícula ou do úmero, asfixia perinatal, e, menos frequentemente, hemorragia subdural e paralisia facial. O controle glicêmico rigoroso pré-concepção e durante a gestação associa-se com menor morbimortalidade perinatal. Assim, o controle do DMG representa tarefa de fundamental importância para impedir sequelas em neonatais. (AU)

The gestational diabetes mellitus (GDM) is associated with an increased risk of fetal, neonatal, and possibly long-term complications. The rates of spontaneous abortion, stillbirth, congenital malformations, and perinatal morbidity and mortality are higher in infants of a diabetic mother than in pregnancies with normal glycemic control. The main neonatal complications are: macrosomia, neonatal hypoglycemia, iron deficiency, changes in cardiac and respiratory function, hyperbilirubinemia, neurological abnormalities, hypocalcemia, hypomagnesemia and polycythemia. Macrosomia predisposes to birth injury, especially shoulder dystocia, increased risk of brachial plexus injury, clavicular or humeral fractures, perinatal asphyxia, and, less often, subdural hemorrhage and facial palsy. Strict glycemic control preconception and during pregnancy is associated with lower perinatal morbidity and mortality. Thus, GDM control is of paramount importance to prevent neonatal harm. (AU)

Desequilíbrios musculares entre flexores dorsais e plantares do tornozelo apóstratamento conservador e acelerado da ruptura do tendão calcâneo / Muscle imbalance between ankle dorsiflexors and plantarflexors after conservative and accelerated treatment of Achilles tendon rupture

A ruptura do tendão calcâneo (TC) reduz a sobrecarga mecânica dos flexoresplantares (FP) do tornozelo. Essa alteração muda o equilíbrio natural entre os FP eflexores dorsais (FD) do tornozelo. O objetivo do estudo foi avaliar as razões isocinéticas concêntricas convencionais de torque de pacientes submetidos a tratamento cirúrgico de ruptura aguda do TC após dois protocolos diferentes de reabilitação. Após procedimento cirúrgico para reconstrução do TC, a amostra foi dividida de forma intencional em dois grupos: conservador (GC, 11 homens, 41,3±7,9 anos) e grupo acelerado (GA, 13 homens, 43,5±13,7 anos). O GC permaneceu com imobilização gessada no tornozelo por seis semanas (tratamento tradicional), enquanto o GA usou uma órtese robofoot em posição neutra e, após duas semanas, iniciou mobilização e apoio precoce do tornozelo, com reabilitação por seis semanas. Após 3 meses de pós-operatório, a razão do torque concêntrico máximo dos FD pelos FP do tornozelo foi avaliada por dinamômetro isocinético. As razões de torque do lado operado se mantiveram superiores às do lado saudável mesmo após 3 meses de pós-operatório (p<0,05). Não foi encontrada diferença no equilíbrio muscular entre os grupos. Pode-se concluir que os dois grupos requerem um período mais longo de reabilitação para recuperar o equilíbrio natural do tornozelo no lado operado.

Achilles tendon rupture reduces ankle plantarflexor (PF) muscles mechanical overload. This change in the ankle joint mechanics changes the natural muscle balance between dorsiflexor (DF) and PF muscles. The purpose of this study was toassess such imbalance by concentric conventional isokinetic torque ratios of patients who underwent different rehabilitation protocols after surgical repair of the Achilles tendon. After surgery, subjects were assigned to either a conservative or to an accelerated rehabilitation group. The conservative group (11 men, 41.3±7.9 years old) remained with a plaster cast for 6 weeks after surgery. The accelerated group (13 men, 43.5±13,7 years old) used a “robofoot” cast for 2 weeks and under wentankle mobilization and early weight bearing for a period of 6 weeks post immobilization. At 3 months post-surgery the ratio between the maximal concentric DF torque and the maximal concentric PF torque was evaluated with an isokinetic dynamometer. Torque ratios on the surgery side were higher (p<0.05) than on the sound side in both groups. No differences of muscle balance could be found between the groups. These results suggest that both groups require further rehabilitation to regain the natural muscle balance between surgery-side ankle DF and PF muscles.