Chaojun Zheng1, Dongqing Zhu, Feizhou Lu, Yu Zhu, Xiaosheng Ma, Xinlei Xia, Robert Weber, Jianyuan Jiang. 1. Departments of *Orthopedics and †Neurology, Huashan Hospital, Fudan University, Shanghai, China; ‡Department of Orthopedics, The Fifth People's Hospital, Fudan University, Shanghai, China; and §Department of Physical Medicine and Rehabilitation, Upstate Medical University, State University of New York at Syracuse, Syracuse, New York, U.S.A.
Abstract
PURPOSE: To compare repetitive nerve stimulation (RNS) between Hirayama disease (HD) and amyotrophic lateral sclerosis (ALS). METHODS: The 3-Hz RNS test was performed on bilateral abductor pollicis brevis, abductor digiti minimi, middle deltoid, and upper trapezius muscles in 33 HD patients and 37 ALS patients. RESULTS: In HD patients, none of tested muscles showed any abnormal decrements (≥10%). Significant decrements were observed in 73% of the ALS patients, and decrements were more frequently observed in proximal muscles (deltoid: 70.3%; trapezius: 48.6%). Illness duration did not correlate with decrement percentage in either patient group, and there was no relationship between decrement incidence and ALS diagnostic category (P > 0.05). CONCLUSIONS: The significantly different RNS results between ALS and HD patients support the application of RNS, especially performing RNS in proximal muscles, as a supplementary test in distinguishing these two diseases, even in the early stages. These results may also imply a difference in underlying pathophysiology between ALS and HD.
PURPOSE: To compare repetitive nerve stimulation (RNS) between Hirayama disease (HD) and amyotrophic lateral sclerosis (ALS). METHODS: The 3-Hz RNS test was performed on bilateral abductor pollicis brevis, abductor digiti minimi, middle deltoid, and upper trapezius muscles in 33 HDpatients and 37 ALSpatients. RESULTS: In HDpatients, none of tested muscles showed any abnormal decrements (≥10%). Significant decrements were observed in 73% of the ALSpatients, and decrements were more frequently observed in proximal muscles (deltoid: 70.3%; trapezius: 48.6%). Illness duration did not correlate with decrement percentage in either patient group, and there was no relationship between decrement incidence and ALS diagnostic category (P > 0.05). CONCLUSIONS: The significantly different RNS results between ALS and HDpatients support the application of RNS, especially performing RNS in proximal muscles, as a supplementary test in distinguishing these two diseases, even in the early stages. These results may also imply a difference in underlying pathophysiology between ALS and HD.