Hand-arm vibration syndrome and its prevalence in the present status of private forestry enterprises in Japan

Summary Currently there are no limitations on age of employment on private forestries in Japan. Hence, it was hypothesized that in these kind of enterprises, elderly chain saw operators, or those with long-term exposure, might be at higher risk of developing hand-arm vibration syndrome (HAVS). We consequently investigated the prevalence of HAVS in 447 chain saw workers on private forestries in Gifu Prefecture, Japan, with particular reference to age and exposure period. Of this population, 43 (9.6%) had signs and symptoms of vibration-induced white finger (VWF), and among these workers the severity of finger blanching was significantly correlated (P < 0.01) with the exposure period. Classification of all subjects by exposure period showed that workers with 30 years' exposure had higher prevalences of VWF (20.9%) and numbness of the hands (25.4%) compared to other groups. Significant differences (P < 0.01) were found between the functional capacities of workers with VWF and those of control subjects. We concluded that (a) the elderly chain saw operators and those with longer exposure should be moved to other jobs with a lower or no risk of exposure to vibration, and (b) the results of screening tests, even without cold water immersion (which we did not employ, in order to protect workers' hands), could be helpful for the identification of workers with VWF.     

Surgical-management of carcinoma of the middle and distal bile-duct

Forty patients underwent surgical resection for cancer of the middle and distal bile duct. Nineteen patients underwent a curative resection with 3- and 5-year survival rates of 63% and 48%, respectively. None of the patients who underwent a palliative resection survived two years. The factor most strongly associated with recurrence was the presence of tumor in the surgical margin. Recurrence was frequent in patients with disease in the middle portion of the bile duct who underwent extrahepatic biliary resection with choledochojejunostomy, while lower bile duct cancer was associated with peri-aortic or retroperitoneal recurrence. Pancreatoduodenectomy, with combined resection of the portal vein in middle bile duct cancer, regional lymphadenectomy, including peri-aortic lymph nodes and nerve plexus is required for curative resection of middle and distal biliary carcinoma beyond the early noninvasive stage.     

Clinical analysis of ossified thoracic ligaments and thoracic disc hernia]

Thoracic lesions present several clinical problems, particularly in their diagnosis and treatment, compared with cervical or lumbar lesions. Since 1983, 18 cases of thoracic space lesions, excluding spinal tumors or trauma have been experienced: nine cases of ossification of yellow ligament (OYL), five of ossification of posterior longitudinal ligament (OPLL), and four of disc hernia (DH). In these 18 patients, problems of clinical manifestations, neuroradiological examination, and surgical approaches are analyzed and discussed. As clinical manifestations, there was a preponderant occurrence in males in the OYL group, while in the OPLL group all the patients were females. OYL and DH occurred at lower thoracic levels. Thirteen of the 18 patients showed combined lesions either in the cervical or in the lumbar regions, such as cervical OPLL, cervical spondylosis, lumbar DH, and lumbar canal stenosis. In the neuroradiological examinations diagnosis of the upper thoracic lesions was difficult. Computed tomography (CT) scan with intrathecal metrizamide injection seemed essential for examination of ossified thoracic lesions. However, because CT imaging of the entire spine is impractical, efficient use of this examination requires previous localization of the offending vertebral level from either the neurological findings or other neuroradiological examinations such as myelography. Magnetic resonance imaging seemed most useful for ruling out the thoracic compressing lesions. As for surgical approaches, posterior decompression was effective for OYL and the anterior approach was useful for OPLL and DH. In patients with "tandem lesions," neurological and neuroradiological findings played an important role in deciding the responsible site.     

Clinical observations of juvenile nonprogressive muscular atrophy localized in hand and forearm

Summary Twenty-seven patients with juvenile nonprogressive muscular atrophy localized in the hand and forearm were analyzed. The clinical characteristics were juvenile male occurrence, insidious onset, specific distribution of localized muscular atrophy and a stationary course. On electromyography, denervation voltage (or giant NMU) is found in the atrophied muscles and sometimes in contralateral nonatrophied ones. Sensory disturbance was not remarkable. Although the etiological factor was not known, strenuous exercise of arms in sports was noted frequently in the history.

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Zusammenfassung 27 Patienten mit juveniler nonprogressiver Muskelatrophie, lokalisiert an der Hand und dem Vorderarm wurden analysiert. Klinisch charakteristische Merkmale waren Vorkommen bei jungen Männern, schleichender Beginn, lokalisierter Befall der erwähnten Muskelgruppe und stationärer Verlauf nach einer anfänglichen Progression. Elektromyographisch wurde eine Denervation in den atrophischen Muskeln und manchmal in den Muskeln der kontralateralen Seite bemerkt. Sensible Ausfälle waren nicht eindrücklich. Obgleich die Ätiologie nicht klar war, wurde häufiger Gebrauch der Hand im Sport in der Krankheitsgeschichte bemerkt.

     

Intraventricular aneurysms--three case reports

Three rare cases of purely intraventricular aneurysms are described, including a unique aneurysm in the fourth ventricle. A 30-year-old female, a 47-year-old male, and an 11-year-old girl presented with disturbance of consciousness due to massive intraventricular hemorrhage. Digital subtraction angiography revealed an idiopathic peripheral aneurysm in the fourth ventricle in the first patient, and aneurysms in the lateral ventricle associated with moyamoya disease in the latter two patients. The former two aneurysms were treated surgically and histologically confirmed to be pseudoaneurysms. The latter aneurysm disappeared spontaneously within 2 months after onset. The aneurysm in the lateral ventricle was resected via a parietal corticotomy with stereotactic insertion of an 8-Fr silicone tube to guide the approach route. This method was very useful because computerized neuronavigation was not available. The aneurysm in the fourth ventricle was resected via a midline suboccipital approach with C-1 laminectomy. Conservative treatment is usually recommended initially for patients with intraventricular aneurysm because spontaneous cure often occurs. We recommend direct surgery if the size of the aneurysm remains unchanged, because the risk of surgery has decreased recently owing to new techniques for neuronavigation.     

Revised new brain retractor: characteristics and new indications--technical note

Revisions were made to our new brain retractor with respect as follows. A knob was added to each shaft of the new brain retractor to facilitate handling. The angle between the shaft and the blade can now be adjusted from 60 to 135 degrees, which is useful in deep, narrow operative fields. Three blade lengths (20, 30, and 40 mm) are now available. The new retractor is entirely made from titanium. This revised brain retractor is very useful for the dissection of sylvian and interhemispheric arachnoid membranes, as well as in the extirpation of intracerebral masses via corticotomy.     

Nerve distribution to the human knee joint: anatomical and immunohistochemical study

The nerve distribution to the knee joints was analyzed in 5 cadavers and 10 joint capsules specimens were resected during total knee arthroplasty. We found nerve fibers immunoreactive for anti-substance P antibody in the articular capsule. By confocal laser scanning microscopy, we evaluated the three-dimensional structures of the Ruffini's corpuscles and the free nerve endings, both of which were immunoreactive for anti-protein gene product 9.5.     

Spreading patterns of hilar bile duct cancer

Spreading patterns of hilar bile duct cancer were investigated based on cases resected in our institution and reported cases in Japan. Forty-seven patients underwent resection in our institution during the past 20 years. Three patients(12%) survived for more than 5 years. The depth of tumor invasion was m or fm in 4 and se or si in 26 patients. Positive cancer invasion in the cut end was classified as hm2 or dm2 in 8 patients and em2 in 13. Twenty-four (60%) of 40 patients investigated histologically had positive lymph node metastases. Invasion of the ss layer or deeper perineural invasion occurred in 92.5%. In terms of direct invasion of the liver, hinf1 occurred in 20(42.6%). Fourteen(29.8%) han invasion of the portal vein(more than vs1). Patients with invasion of the hepatic artery were not resected. The 5-year survival rate by cancer stage was 38% in stage I, 20% in stage II, 16% in stage III, and 0% in stage IV. Surgery was assessed as Cur A in 19 patients (46.3%), Cur B in 7 (17.1%), and Cur C in 15 (36.6%). In Cur A patients the 5-year survival rate was 18%, while that for our Cur B and Cur C patients was 0%. Our patient series was more advanced in terms of cancer stage than the statistical Japanese series and both included a significant number of noncurative cases. Hepatic resection of the right or left lobe, medial segment, and S4a and S5, combined resection of the caudal lobe, and combined portal vein resection are important as radical surgery in the treatment of this cancer.     

Does severe nutcracker phenomenon cause pediatric chronic fatigue?

BACKGROUND: In the past five years we experienced 9 fatigued disabled children who were intermittently or persistently absent from school. PATIENTS: They had been suspected to be burdened with psychosomatic disorders, having orthostatic hypotension, postural tachycardia, or other autonomic dysfunction symptoms. RESULTS: Investigating the cause of moderate orthostatic proteinuria in some of them, we found by chance severe typical nutcracker phenomenon (NC), which was present in all 9 children complaining of chronic fatigue. CONCLUSION: Their symptoms filled the criteria of chronic fatigue syndrome or idiopathic chronic fatigue (CFS/CF). An association between severe NC and autonomic dysfunction symptoms in children with CFS/CF has been presented.     

In vitro metabolism of fenthion and fenthion sulfoxide by liver preparations of sea bream, goldfish, and rats.

The in vitro metabolism of fenthion and its sulfoxide (fenthion sulfoxide) in sea bream (Pagrus major) and goldfish (Carassius auratus) was investigated and compared with that in rats. Fenthion was oxidized to fenthion sulfoxide and the oxon derivative, but not to its sulfone, in the presence of NADPH by liver microsomes of sea bream, goldfish, and rats. These liver microsomal activities of the fish were lower than those of rats but were of the same order of magnitude. The NADPH-linked oxon- and sulfoxide-forming activities of liver microsomes of the fish and rats were inhibited by SKF 525-A, metyrapone, alpha-naphthoflavone, and carbon monoxide. The oxidizing activity to fenthion sulfoxide was also inhibited by alpha-naphthylthiourea. Several cytochrome P450 isoforms and flavin-containing monooxygenase 1 exhibited these oxidase activities. Fenthion sulfoxide was reduced to fenthion with liver cytosol of the fish and rats upon addition of 2-hydroxypyrimidine, N(1)-methylnicotinamide, or butyraldehyde, each of which is an electron donor of aldehyde oxidase, under anaerobic conditions. The activity was inhibited by menadione, beta-estradiol, and chlorpromazine, which are inhibitors of aldehyde oxidase. The activities in the fish livers were similar to those of rat liver. Aldehyde oxidase purified from the livers of sea bream and rats exhibited the reducing activity. Thus, fenthion and fenthion sulfoxide are interconvertible in fish and rats through the activities of cytochrome P450, flavin-containing monooxygenase, and aldehyde oxidase.