EMG examination of at least four muscles was also conducted on all FM subjects, and 10 of 14 EDX controls.
Needle EMG examination was successfully carried out in 28 of 29 "FM Only" subjects.
To assure standard results during the EMG examination
, the electrodes were placed accurately at the area of muscle belly contraction .
In consequence, since the clinical feature disappeared, a surface EMG examination could no longer be performed.
Although an EMG examination to prove the brief interruptions of tonic muscle activity which characterize negative myoclonus (i.e., asterixis) was not possible because the symptoms disappeared within a short period of time after thrombolysis, the clinical presentation, as documented in the video, was typical for asterixis.
On EMG examination, there was increased insertional activity and the presence of abnormal spontaneous electrical activity at rest in the left 1st DI and ADM with a 50% reduction in interference patterns during maximum voluntary contraction in both of these muscles.
On EMG examination, there was increased insertional activity and the presence of abnormal spontaneous electrical activity at rest in the right 1st Dl, ADM, and FCU, with a 75% reduction in interference patterns during maximum voluntary contraction in the right 1st DI and ADM.
Compared with the diaphragm and the intercostal and paraspinal muscles, RA displays several advantages for EMG examination
. RA is a relatively safe and convenient muscle for EMG recording.
Needle EMG examination
revealed a small amount of denervation potentials in APB and ADM also motor unit rarefaction, increase of polyphasic motor unit potantials (MUP) and chronic neurogenic changes in APB, ADM and EIP muscles, whereas needle EMG findings of the biceps and triceps were normal (Table 2).
Both CTS classification systems identified bilateral median motor and sensory involvement with a demyelinating neuropathic process, but only the GEHS classification system demonstrated electrophysiological evidence of motor fiber axonopathy in the bilateral APBs by EMG examination
of the upper segment of the trapezius muscle revealed reduced recruitment of motor units, increased polyphasia, and occurrence of mild PSWs and fibrillation potentials.