The Effects of Charcot-Marie-Tooth (CMT) Disorder on Balance

Abstract

CMT is a common genetic neuromuscular disorder that affects approximately 150,000 Americans. Muscular atrophy due to improper neurological function affects the peripheral regions of the body which affects gait, balance, and many other basic daily functions. PURPOSE:The purpose of this study was to describe the balance characteristics of 3 siblings diagnosed with CMT. Subject 1 is a 49-year-old male, subject 2 is a 43-year-old male, and subject 3 is a 45-year-old female. METHODS: Informed consent was obtained from each subject prior to testing. The subjects were instructed to try to maintain their balance until the researcher informed them that the trial had been completed. Each subject performed 3 trials for each of the following conditions: right foot eyes open (RFEO), left foot eyes open (LFEO), both feet eyes open (BFEO), and both feet eyes closed (BFEC) for a total of 12 trials. All trials were randomly ordered. An AMTI force plate sampling at 600 Hz. collected the data. The subjects were instructed to concentrate on a single printed dot located on a piece of paper placed 20 feet in front of them during the eyes open trials to help them keep their balance, but were also instructed to use any acquired means of maintaining balance during the trials. The software was set to capture 60 seconds of data for each trial but was stopped when the subjects' suspended foot touched the floor during the single leg trials or when either foot left the force plate during the double leg trials. The force plate was set to automatically offset for existing force when the trial started so that anterior/posterior (AP) and medial/lateral (ML) forces could be easily calculated throughout the trial. RESULTS: The overall means for AP and ML forces, AP and ML center of pressure deviations (COP) and time to loss of balance were: AP force (BFEC = 8.71 1N, BFEO = 3.239N, LFEO = 26.905N, RFEO = 15.292N), ML force (BFEC = 4.570N, BFEO = 2.360N, LFEO = 44.059N, RFEO = 43.997N), AP COP (BFEC = 0.200m, BFEO = 0.253m, LFEO = 0.158m, RFEO = 0.163m), ML COP (BFEC = 0.200m, BFEO = 0.204m, LFEO = 0.120m, RFEO = 0.126m), & Time (BFEC = 49.505s, BFEO = 60.000s, LFEO = 1.525s, RFEO = 2.367s). CONCLUSION: These data sets represent some of the first of its kind in the study of CMT and will form the basis of further and more intense investigations. The results clearly show that balance is compromised in CMT and strategies need to be investigated to address this problem.