The value of electromyography in diagnosis of myotonic dystrophy / 重庆医学

ABSTRACT

Objective To explore the value of electrophysiology in diagnosis of myotonic dystrophy .Methods Electromyogra-phy(EMG) and nerve conduction were detected in 26 myotonic dystrophy patients(myotonia group) .Myotonic discharges were de-tected in 25 patients with non-tonic neuromuscular disease(control group) .Results The main features of EMG in myotonia group were myotonic discharges ,myogenic damage ,and normal nerve conduction .There was no myotonic discharges in control group .The positive rate of myotonic discharges of abductor pollicis brevis was 87 .5% .The positive rate of myotonic discharges of extensor digitorum communis was 77 .8% .The positive rates of myotonic discharges of anterior tibial muscle ,quadriceps femoris and trian-gular muscle are 57 .1% ,45 .5% and 45 .5% respectively .Conclusion Myotonic dystrophy distinguished from other neuromuscular disease might be mainly based on myotonic discharges and myogenic damage .Myotonic discharges were mainly observed in the small hand muscles .However ,the positive rate of abductor pollicis brevis ,which has the highest chance of myotonic discharge ,was less than 100% .