Electromyographic analysis in spinal progressive muscular atrophy, juvenile unilateral muscular atrophy, neural progressive muscular atrophy and myeloradiculoneuritis.

Recently, as diagnostic aids of neurological science, not only electromyography but also other techniques such as motor nerve conduction velocity, evoked potentials and strength-duration curve have been performed. In this paper, the first, the standard value of conduction velocities and the critical value of reduced conduction velocities in pathologic condition were discussed, because the problems of the values have not been determined with constancy yet. The second, applying four procedures to spinal progressive muscular atrophy, juvenile unilateral muscular atrophy, neural progressive muscular atrophy (Charcot-Marie-Tooth disease) and myeloradiculoneuritis. mutual interrelation of the measured values was studied and discussed the parallelism to clinical sigh and symptom with the disease. In combination of electromyography with subjective and qualitative express;on and the other techniques with objective or numerical expression, the pathognomy of the cases could be assumed and, too, the course of the diseases in repeating the procedures frequently. In clinical neurology electromyography with a unipolar and concentric needle electrode has been employed as a diagnostic aid. However, since in 1948 Hodes, Larrabee and German1l pointed out clinical application of conduction velocity of the motor axons, many investigators have reported motor nerve conduction velocity in normal and neurological subjects_ Among a few electrodiagnostics, Trojaborg2 l ( 1962) applied the technique of electromyography, motor nerve conduction velocity and strength-duration curve to polyneuropathy and non-traumatic mononeuropathy, and studied their correlation of the methods. Furthermore, Dawson and ScoW) (1949) recorded nerve action potentials through the skin in man, which included evoked potentials measured at the wrist or ankle stimulating on the elbow or knee and sensory nerve conduction velocity from the finger or toe to the wrist or ankle, and thereMs=!J't~. ~!*TFP. f_lfi"t$:5l Received for publication May 9, 1966_