The clinical and electrophysiological characteristics of flail arm syndrome
10.3760/cma.j.issn.0254-1424.2021.01.005
- VernacularTitle:连枷臂综合征的临床及神经电生理特点分析
- Author:
Fang LIU
;
Changdong SONG
;
Hengfang LIU
;
Min ZHANG
;
Shuyan FENG
;
Liuyi LI
- From:
Chinese Journal of Physical Medicine and Rehabilitation
2021;43(1):21-24
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the clinical and electrophysiological characteristics of flail arm syndrome (FAS).Methods:Clinical and electrophysiological data were collected on 13 FAS patients and 31 persons with upper limb onset amyotropic lateral sclerosis (UL-ALS), including the amplitude of compound muscle action potential (CMAP) related to median nerve, ulnar nerve, and axillary nerve motor conduction. A split-hand index (SI) was calculated by dividing the CMAP amplitude of abductor pollicis brevis by that of the abductor digiti minimi. Clinical features, the CMAP amplitudes and SIs were compared between the FAS and UL-ALS patients.Results:Compared with UL-ALS patients, the age at onset among the FAS patients was older (averaging 60.9 years). The development to the second stage was longer (24±6 months). The upper limb reflexes of 15% of the FAS patients had disappeared and those of 77% were weakened, while the lower limb reflexes of 54% of the FAS patients were active and 38% were weakened, significantly different from the UL-ALS patients. However, there were no significant differences in the CMAP amplitudes of the median and ulnar nerves, nor in SI between the FAS and UL-ALS patients. The SIs of the FAS patients with upper motor neuron signs were significantly lower than those of FAS patients without such signs. Among the FAS patients, the average CMAP amplitude of the ulnar nerve was the highest, followed by those of the median and axillary nerves. Among the UL-ALS patients, however, the average CMAP amplitude of the ulnar nerve was not significantly different from that of the axillary nerve.Conclusions:FAS patients with upper motor neuron signs are more likely to have slip hand. The CMAP amplitude of their axillary nerve tends to be lower than that of their median and ulnar nerves. FAS seems to be a special type of ALS.
