Effects of the walking independence on lower extremity and trunk muscle activity during straight-leg raising following incomplete cervical cord injury.

The purpose of this study was to compare the acceleration and surface electromyography (EMG) of the lower extremity and trunk muscles during straight-leg raising (SLR) in patients with incomplete cervical cord injury according to their levels of walking independence. Twenty-four patients were measured acceleration and EMG during SLR held for 10 s. Data were analyzed separately for the dominant and nondominant sides and compared between the nonindependent (NI) and independent (ID) groups based on their levels of walking independence. Frequency analysis of the EMG showed that the high-frequency (HF) band of the contralateral biceps femoris (BF) in the ID group and bands below the medium-frequency (MF) of the BF and the HF and MF bands of the rectus abdominis in the NI group were significantly higher during dominant and nondominant SLR. During the nondominant SLR, the low-frequency band of the internal oblique and the MF band of the external oblique were significantly higher in the NI group. The ID group mobilized muscle fiber type 2 of the BF, whereas the NI group mobilized type 1 of the BF and types 2 and 1 of the trunk muscles to stabilize the pelvis. This result was more pronounced during the nondominant SLR.

Putamen Atrophy Is a Possible Clinical Evaluation Index for Parkinson's Disease Using Human Brain Magnetic Resonance Imaging.

Parkinson's disease is characterized by motor dysfunction caused by functional deterioration of the substantia nigra. Lower putamen volume (i.e., putamen atrophy) may be an important clinical indicator of motor dysfunction and neurological symptoms, such as autonomic dysfunction, in patients with Parkinson's disease. We proposed and applied a new evaluation method for putamen volume measurement on 31 high-resolution T2-weighted magnetic resonance images from 16 patients with Parkinson's disease (age, 80.3 ± 7.30 years; seven men, nine women) and 30 such images from 19 control participants (age, 75.1 ± 7.85 years; eleven men, eight women). Putamen atrophy was expressed using a ratio based on the thalamus. The obtained values were used to assess differences between the groups using the Wilcoxon rank-sum test. The intraclass correlation coefficient showed sufficient intra-rater reliability and validity of this method. The Parkinson's disease group had a significantly lower mean change ratio in the putamen (0.633) than the control group (0.719), suggesting that putamen atrophy may be identified using two-dimensional images. The evaluation method presented in this study may indicate the appearance of motor dysfunction and cognitive decline and could serve as a clinical evaluation index for Parkinson's disease.

Segmentation of cervical intervertebral disks in videofluorography by CNN, multi-channelization and feature selection.

PURPOSE: Dysphagia has a large impact on the society because it is a risk factor of malnutrition and aspiration pneumonia, and therefore, it is necessary to elucidate the entire mechanism of dysphagia. In this study, we propose a segmentation method of cervical intervertebral disks (CIDs) in videofluorography (VF) by use of patch-based convolutional neural network (CNN), our multi-channelization (MC) method and image feature selection. METHODS: Twenty image filters are individually applied to a VF frame image to generate feature images. One color image, called a multi-channelized image, is generated by setting three selected feature images to its red, green and blue channels. Patch-based CNN is applied to the MC image, and the segmentation accuracy of CIDs is evaluated by the pixel-based F-measure. The combination of the three feature images is optimized by the simulated annealing method. RESULTS: The proposed method was applied to actual VF dataset consisting of 19 patients and 39 healthy participants. The segmentation accuracy was 59.3% in the F-measure when Sobel and morphological top-hat filters were selected in MC, whereas it was 56.2% when original frame images were used. CONCLUSION: The experimental results demonstrated that the proposed method was able to segment CIDs from actual VF and also that the MC method was able to increase the segmentation accuracy by approximately 3%. In this study, LeNet was used as CNN. One of our future tasks is to use other CNNs.

The Effect of the Cervical Orthosis on Swallowing Physiology and Cervical Spine Motion During Swallowing.

Cervical orthosis is used to immobilize the neck in various disorders such as trauma and post-operation. However, it is still uncertain how cervical orthosis restricts the degree of movement of the cervical spine during swallowing and how they affect swallowing physiology. The purpose of this study was to evaluate these issues using the Philadelphia(®) Collar. We conducted videofluorography of swallowing in 39 healthy subjects (23 men, 16 women; mean age of 34.3 years) with and without cervical orthosis. To compare the two conditions regarding the cervical spine motion, we determined the angular and positional changes of the occipital bone (C0) and each cervical vertebra (C1-C7) from the oral phase to the pharyngeal phase. Similarly, to compare swallowing physiology, we assessed the start and end times and the durations of soft palate elevation, rapid hyoid anterosuperior movement, epiglottis inversion, closure of the laryngeal vestibule, and pharyngoesophageal segment (PES) opening. Finally, we compared the transit times of contrast agent in the two conditions. The respective extensions of C1, C2, and C3 were 0.31°, 0.07°, and 0.05° (mean) with cervical orthosis, and the respective flexions of C1, C2, and C3 were 0.98°, 1.42°, and 0.85° (mean) without. These results suggested that cervical orthosis restricted the flexion of C1-C3. Analysis of swallowing physiology revealed that the average durations of hyoid anterosuperior elevation, epiglottic inversion, and PES opening were prolonged by 0.09, 0.19, and 0.05 s, respectively. In conclusion, the cervical orthosis restricted the movement of the cervical spine during swallowing and changed swallowing physiology.

Cervical spine motion during swallowing.

PURPOSE: There have been several studies regarding the relationship between deglutition and the cervical spine; however, the movement of the cervical spine during deglutition has not been specifically studied. The purpose of the present study was to clarify how the cervical spine moves during normal deglutition. METHODS: We conducted videofluorography in 39 healthy individuals (23 men; 16 women; mean age, 34.3 years) with no evidence of cervical spine disease and analyzed images of the oral and pharyngeal phases of swallowing using an image analysis technique. Analyzed sections included the occiput (C0) and the first to seventh cervical vertebrae (C1-C7). The degrees of change in angle and position were quantified in the oral and pharyngeal phases. RESULTS: In the pharyngeal phase, C1, C2, and C3 were flexed (the angle change in C2 was the most significant with a mean flexion angle of 1.42°), while C5 and C6 were extended (the angle change in C5 was the most significant with a mean extension angle of 0.74°) in reference to the oral phase. Angle changes in C0, C4, and C7 were not statistically significant. C3, C4, C5, and C6 moved posteriorly (the movement in C4 was the most significant, mean = 1.04 mm). C1, C2, and C3 moved superiorly (the movement in C2 was the largest, mean = 0.55 mm), and C5 and C6 moved inferiorly. Movements in C0 and C7 were not statistically significant. CONCLUSIONS: These findings suggest that the cervical spine moves to reduce physiological lordosis during deglutition.