ABSTRACT
Twenty normal individuals were submitted to facial nerve electroneurography using different techniques in order to determine the most accurate to obtain the latencies and amplitudes of the compound muscle action potentials (CMAP) of the facial muscles. First of all it was determined in which muscle or muscle group highest amplitude CMAP could be recorded with the lowest variability between sides and in test-retest. Different techniques were studied in order to determine which could give the best results. This was shown to be an arrangement of bipolar surface electrodes fixed to a plastic bar. The records with higher amplitude where obtained from the nasolabial fold muscles. Therefore 65 normal volunteers were examined using this technique and recording the potentials obtained over the nasolabial fold muscles. Normal values were determined (latency lower than 4.5 ms and amplitude larger than 2 mV--95% confidence limits).
Subject(s)
Facial Muscles/physiology , Facial Nerve/physiology , Action Potentials , Adolescent , Adult , Aged , Analysis of Variance , Electromyography , Electrophysiology , Female , Humans , Male , Middle AgedABSTRACT
To determine the variability of the abnormalities found in the electroneurography (ENG) of the facial nerve in cases of Bell's palsy during the initial two week period was one of the objectives of the authors. A second one was to investigate the value of ENG as a tool to determine an early prognosis of recovery utilizing two different methods. In the first one the amplitude of the compound muscular action potential (CMAP) obtained on the paralyzed side was compared to this potential on the opposite (normal) side. The second method compared the CMAP on the paralyzed side to normal standardized data from normal individuals. A group of 33 patients with Bell's palsy was followed until total recovery of for at least 4 months, if the recovery was not achieved earlier. It was observed that amplitude of the CMAP become stable towards the sixth day of palsy and this is a good time to establish the prognosis. Another conclusion is that both methods were equivalent to determine the prognosis in Bell's palsy.
Subject(s)
Facial Nerve/physiopathology , Facial Paralysis/physiopathology , Action Potentials , Adolescent , Adult , Aged , Analysis of Variance , Child , Child, Preschool , Electromyography , Electrophysiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Time FactorsABSTRACT
Isolated and painless infraspinatus atrophy and weakness are described in two top-level volleyball players. EMG revealed isolated denervation of the infraspinatus muscle. One athlete continued playing and his clinical features have not changed. The other recovered her muscle bulk and strength after stopping playing. These findings were attributed to intense activity of the shoulder joint, without any direct trauma. On clinical grounds, we did not consider these cases as true examples of entrapment neuropathy. Pathogenesis was related to traction of the distal branch of the suprascapular nerve during the act of reception of the ball ("Manchete").
Subject(s)
Athletic Injuries/diagnosis , Muscular Atrophy, Spinal/diagnosis , Adult , Electromyography , Female , Humans , Male , Muscles/innervation , Shoulder Injuries , Shoulder Joint/innervationABSTRACT
In this study it is, intended to establish the more appropriate points to register the compound action potential from m. frontalis m. orbicularis oculi and nasolabial fold muscles. The optimum site for stimulating electrodes and differences between the first and the last compound action potentials after 20 consecutive stimuli delivered at 1 Hz were analysed.
