Takahiro Yamanoi

Simultaneous strain measurement with determination of a zero strain reference for the medial and lateral ligaments of the ankle.

The strain changes of the central part of the anterior talofibular ligament (ATFL), the posterior talofibular ligament (PTFL), the calcaneofibular ligament (CFL), and the tibiocalcaneal ligament (TCL) were measured simultaneously for a full range of ankle motion. Twelve fresh frozen amputated ankles were used. To measure the strain changes of the ligaments, a Galium-lndium-filled silastic strain transducer was implanted in the center of each ligament. The zero strain reference was determined immediately after the measurement of strain changes in five of the 12 ankles by tensile testing of each bone-ligament-bone preparation. The maximum strain change of the ATFL, the PTFL, the CFL and the TFL were 7.9%, 5.9%, 5.3% and 5.2%, respectively. The ATFL was elongated in plantar flexion and shortened in dorsiflexion. The PTFL and the CFL were shortened in plantar flexion and elongated in dorsiflexion. The TCL was the longest around the neutral position and became shorter in planter flexion and dorsiflexion. The results showed that the ATFL was taut in plantar flexion over 16.2°, the PTFL and the CFL were taut in dorsiflexion over 18° and 17.8° respectively, and the TCL was taut between 9.5° of dorsiflexion and 9.5° of plantar flexion. The length change pattern was different among the ankle ligaments, although there was only a slight difference between that of the PTFL and the CFL. This study provides fundamental data useful in studying ankle ligament reconstruction.

Radiographic findings of degeneration in cervical spines of middle-aged soccer players

Twelve amateur veteran soccer players (average age 40.1±5.4 years), who began playing in their teens and who were admitted with symptoms most likely to be related to cervical spondylosis, were examined by cervical radiography. Abnormal radiographic findings included: calcification of anterior longitudinal ligament (25%), anterior (75%) and posterior vertebral spurs (75%), ossicle between spinous processes (75%), calcification of nuchal ligament (Barsony) (58%), ossicle on spinous process (25%), and bony spur of Luschkas joints (83%). It was shown in the stress distribution by finite element method analysis that the stress in heading the ball was applied mainly to the lower parts of the cervical spine. The results of this analysis also corresponded well with some of the radiographic findings.

Equivalent-Current-Dipole-Source-Localization-Based BCIs with Motor Imagery

This chapter will propose a new paradigm for single-trial-electroencephalogram (EEG)-based Brain-Computer Interfaces (BCIs) with motor imagery (MI) [1] tasks. Among such BCIs, the sensorimotor rhythm (SMR)-based ones, when using common spatial patterns (CSPs), require features over broad frequency bands, such as mu, beta and gamma rhythms [2]. Therefore, very high-dimensional feature vectors and continuous-valued patterns necessary for spatio‐ temporally checking the features [3,4] could yield an enormous amount of data and much computational time [5]. So, various data reduction such as downsampling [6,7] and optimal EEG channel configuration [8,9,10] have been investigated for the BCIs.

35. Classification of movement imagery on the basis of single-trial EEGs

The aim of this study was to determine if there is any interhemispheric interaction in somatosensory-evoked potentials (SEPs) by using condition (SI) and test (SII) paired stimulus paradigm. This was examined during both wakefulness and sleep. The SI stimuli were delivered to right median nerve (MN) and SII stimuli were to left MN, with interstimulus interval (ISI) of 0, 5, 10, 20, 50, 100 and 200 ms. Three stimulus modalities (SI, SII, SI + SII) were delivered in cyclic fashion throughout the awake and asleep states. SEPs were obtained as of off-line after grouping the responses according to the wakefulness and sleep stages of II, III/IV and REM. Control SEP showed decreased amplitude of parietal N32–P40 and P40–N60 and increased amplitude of frontal N19–P22 in non-REM sleep as compared to those of wakefulness. The latencies of all peaks (except for P14) were prolonged with greater degree in later components. All these changes returned close to wakefulness during REM sleep. The test response also showed parallel changes with the control responses throughout all ISIs both in wakefulness and sleep. It is concluded that there is no significant inter-hemispheric interaction in sensory input between two hemispheres during both wakefulness and sleep.