The 1, 103 upper-limb amputees who were onfiles in 3 prosthetics facilities in Kinki area of Japan were asked to join our study by mail, of which the 427 amputees answered our questionnaires. The average age of amputees was 55.7 years. Eighty-two percent of amputees were male and 18 percent were female. The average elapsed period from amputation to this survey was 23.7 years. Ninety-two percent of the amputees were caused by trauma (77% industrial accidents, 7% traffic accidents, 4% war, 14% other accidents), 5% by congenital amputations, 2% by diseases, and 1% by others. Fifty-six percent of the patients occupations at the time of amputation were the manual laborers. Whereas, only 13% were the manual laborers and 31% were unemployed at the time of this survey. Level of amputation were classified as follows: shoulder disarticulation (2%), above-elbow (32%), elbow disarticulation (4%), below-elbow (52%), wrist disarticulation (11%). Seventeen percent of the unilateral amputees were using two or more types of prostheses. Eighty percent of the amputees were using the cosmetic prostheses, 21% the body-powered prostheses, 11% the working prostheses, only 1% the electrically-powered prostheses, and 4% no prosthesis. Seventy-six percent of the amputees hoped to use the myoelectric hand. In 110 amputees who were amputated within recent 10 years, the average age of amputation time was 45.9 years, 90% of the amputees were caused by trauma. Forty-seven percent of them were users of the body-powered prostheses, 16% the working prostheses, and 2% the electrically-powered prostheses. In conclusion, the center of living upper-limb amputees were long elapsed, aged male amputees caused by the industrial accidents. In the amputees who received amputation within recent 10 years, main cause of amputation was still industrial injury, many of them were aged already at the time of amputation, and the number of amputees wearing body-powered prostheses was increasing.

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Motor unit firing rates and recruitment thresholds at 3 different kinds of controlled isometric voluntary contraction were studied employing precision decomposition techniques. Electro-myographic signals were decomposed into their constituent motor unit action potential trains (MUAPTs) and the firing rates and the recruitment thresholds were identified. In normal triceps brachii muscles, each motor unit (MU) was found to rise its firing rate up to a common maximum level soon after it was recruited. In the paretic triceps muscles in patients with cervical spinal cord injury, MUs with the lower recruitment threshold were found to be with the larger maximum firing rate. MUs in the weaker muscles were found to have the higher maximum firing rate.

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We studied the effect of the anabolic steroid (AS) on the muscle strength and hypertrophy of the lower legs with voluntary movements. The subjects were 25 patients with nervous diseases, 16 males and 9 females, aged from 20 to 77 years (57.7±2.7 years), and the duration of the diseases were between 6 and 110 months (43.4±6.0 months). The patients were divided into two groups, control group (12 patients) with only voluntary exercise of the leg for 8 weeks, and AS group (13 patients) with voluntary leg exercise for 8 weeks plus oral anabolic steroid (oxymetron 20-40mg/day) for 4 weeks in the middle of the leg exercise. In addition to the traditional rehabilitation program, muscle exercise of the leg was performed in the sitting position using Cybex 6000. The patients were ordered to repeat knee extension/flexion isokinetic movements (60 and 180 degree/sec) with full power, 100-200 times/day with appropriate intervals, 5 days/week during 8 weeks of this study. Muscle strength were measured with Cybex 6000. The cross sectional area of the thigh were examined at 20cm below trochanter major by computer tomography. During 4 weeks of AS administration, significant increase of isokinetic and isometric muscle strength either on extension or flexion movements were observed. The increase of the cross sectional area of the exercised thigh was more prominent during 4 weeks of AS administration. As the adverse effects of AS, slight increase in AST, ALT and K was observed in 5 patients and returned within 1-2 weeks after cessation of AS. These results suggest anabolic steroid is significantly effective for muscle strength and hypertrophy.

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We investigated speech errors in Wernicke's aphasia to examine whether and what kind of errors in lexical retrieval are critical in the speech production deficit of Wernicke's aphasia in the Japanese language system. Three right-handed male patients with Wernicke's aphasia due to cerebral infarction were graded as having mild, moderate, or severe aphasia according to the Standard Language Test of Aphasia, Token Test, and Phonetic Discrimination Test. Production of words with 1 to 6 syllables was tested by having patients name objects drawn on a card, and having them repeat or read aloud words written in Kana characters. Production of words with 1 to 4 syllables was tested by having patients read aloud words written in Kanji characters. Speech errors were classified to semantic paraphasia, verbal paraphasia not semantically related to the target word, phonological paraphasia, neologism, conduites d'approche, errors of one-syllable words. Phonological paraphasias were classified as addition, omission, dislocation, or substitution. Errors of dislocation and substitution were classified as vowel or consonant errors. The more severe the aphasia, the higher was the rate of consonant errors. We suggest that impairments in consonant retrieval is critical in the speech production deficit of Wernicke's aphasia in Japanese-speaking patients.

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A catheter electrode to record the surface electromyography (EMG) of cricopharyngeal muscle (CPM) was developed. EMG was measured using this catheter electrode in three normal subjects and six patients with cricopharyngeal dysphagia secondary to brainstem stroke. The catheter electrode was inserted into the esophagus through the nose. The EMG signals were not detectable when the electrode was in the esophagus. The continuous tonic EMG activity gradually increased as the catheter was pulled out from the esophagus to the pharynx. The region where maximum EMG activity was observed was considered to be the cricopharyngeal segment. There was no laterality of surface EMG of CPM in normal subjects, although individual variation was observed. In dysphagic patients, the amplitude of EMG of CPM diminished on the affected side. One speculates that by using the catheter electrode, EMG of CPM can be recorded noninvasively, and thus can be applied to the study of the pathology of cricopharyngeal dysphagia.

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