Clinical and electromyographic analysis of Kennedy’s disease

Abstract

Objective To summarize the clinical and electromyographic features of Kennedy’s disease to provide evidence for early diagnosis. Methods A retrospective analysis was performed on five patients with Kennedy’s disease who were treated at Shengjing Hospital Affiliated to China Medical University from June 2016 to April 2019. All patients underwent electromyography. Results The patients in this group were accompanied by limb weakness at the time of presentation, but the initial symptoms were different. In most cases, the clinical symptoms at the time of presentation are mainly inability to lift, difficulty in going upstairs, difficulty in walking, and difficulty in lifting the upper limbs. Electromyographic analysis showed that in four patients, the amplitude of the sensory nerves decreased or cannot lead out in different level, and the speed was normal or slightly slowed down. There was no abnormal abnormality in sensory nerve conduction velocity and amplitude in one patient. Four patients had a decrease in motor nerve conduction amplitude, and the rate was normal or slightly slowed. In one patient, the incidence of F-waves in the median nerve and tibial nerve was reduced. Five patients had a little bit of spontaneous activity when the muscles of the limbs were at rest, and large motor unit action potentials during light contraction and heavy contraction. When the above clinical and electromyographic manifestations are present, the possibility of Kennedy’s disease should be considered. Conclusion Electromyography is a convenient and rapid examination and can play an appreciated role in the diagnosis and differential diagnosis of Kennedy’s disease. Key words: Kennedy’s disease; Electromyography; Clinical features