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.
Needle electromyography (EMG) of left tibialis anterior and peroneus longus muscles showed increased insertional activity
, fibrillation (2+), positive sharp waves (2+) and reduced recruitment (Table 2).
Prolonged insertional activity
, spontaneous fibrillation potentials, and runs of positive sharp waves were found in the left gastrocnemius, iliofibularis, long digital extensor, and some flexor muscles (Fig 4).
IA = insertional activity
, Fasc = fasciculation, Fib = fibrillation, HF = high-frequency potentials, L = lumbar, N = normal, PPP = polyphasic potentials, PSP = pro- gressive supranuclear palsy, PSW = positive sharp waves, S = sacral.
Mechanically provoked insertional activity
before and after nerve section in rats.
EMG (electromyography) of the lower extremities showed normal insertional activity
in all explored muscles; abnormal spontaneous activity was present in right rectus femoris; increased amplitude and reduced recruitment were present in left anterior tibialis, left gastrocnemius and left rectus femoris.
Myopathic units were found in the deltoid muscle, and needle examination of the tongue revealed normal insertional activity
and normal motor unit potentials.
Electromyography revealed increased insertional activity
, increased polyphasic potentials, and diminished recruitment when measured over the bilateral vastus lateralis, and triceps; a pattern consistent with a myopathy.
The insertional activity
provides valuable information about the state of the muscle and its innervating nerve.
Needle electromyography (EMG) of bilateral tibialis anterior and peroneus longus muscles revealed motor unit potentials of normal amplitude, duration, and phasicity; increased insertional activity
, 2+ fibrillations, 2+ positive sharp waves and reduced recruitment.
The scale of fibrillation potentials is not linear, but the amount of abnormal insertional activity
allows at least some estimate of the extent of injury.
There was abnormal spontaneous electrical activity including increased insertional activity
and the presence of fibrillation potentials and positive waves in both the right and left APBs.