[Mechanical influences on the lumbar spine]. / Výzkum mechanických vlivu na bederní páter.

The author investigated the firmness and elasticity of the lower lumbar vertebrae and intervertebral discs. They confirmed that the intervertebral disc is very firm when exposed to pressure and very coherent when exposed to traction. The locus minoris resistentiae during traction tests and when testing resistance to impacts is the connection between the intervertebral disc and the body of the vertebra. The bodies of vertebrae are less resistant to pressure than lumbar intervertebral discs. When exposed to an impact, imitating bending, the intervertebral disc is torn from the body of the vertebra. The most vulnerable place of the lumbar spine is thus the connection of the vertebra and the intervertebral disc, the site which is also the borderline of the vascular supply which then changes into diffuse supply. Strain at the borderline of firmness or above it can cause degeneration of the intervertebral disc, and if more extensive, even spondylolisthesis.

Indications for endarterectomy and STA-MCA shunts in the brain atherosclerosis.

Altogether 169 operations of patients with occlusion or stenosis of the brain arteries and brain magistral arteries are reviewed. In 151 patients the cause of disease was atherosclerosis. No one of the patients has died. According to the thorough investigation consisting of panangiography, dynamic scintigraphy, sonography, ophthalmodynamometry, CT and other clinical investigations, either extra-intra-cranial shunts (STA MCA), or endarterectomies were carried out. The indications for these operations were elaborated with regards to the cause of tandem changes in arteries or to bilateral atherosclerotic changes of the brain arteries. Out of the total 169 operations, 30 endarterectomies were performed. Only two post-surgical complications have appeared, one of them post STA MCA operation and the other after endarterectomy.

Diagnosis, size, and operation results in 41 acoustic neurinomas.

The diagnosis, size and operation results in 41 acoustic neurinomas (26 females and 15 males) are presented. In one case the tumor was bilateral. Out of the total of 41 tumors, 12.5% were small acoustic neurinomas. As a rule, at diagnosis the tumors were larger in females than in males. Ten of the small and medium size acoustic neurinomas had no brain stem and cerebellar symptoms or signs at all, only the 8th cranial nerve was affected. All large tumors already had brain stem symptoms and one-third of them also had cerebellar symptoms, lesions of further cranial nerves and increasing intracranial pressure. All these findings were always present in giant tumors. Neurootological functional laboratory examinations cannot be replaced by CT because of the possibility of false negative findings in the smallest acoustic neurinomas. CT and functional neurootological laboratory examinations are complementary to each other and they are not screening procedures at all. As regards morbidity and mortality, the surgical results are comparable with those of other authors using microsurgical techniques. As regards the preservation of hearing, the results are among the best particularly in tumors that were diagnosed as small or medium in this series. Thus it is apparent that the size of a diagnosed acoustic neurinoma is more important for surgical results than the chosen approach to the tumor.

Report on research in strength, elasticity and impact resistance of the cervical vertebrae.

The essential part of the research lay in ascertaining the sort of forces damaging in an injury of the cervical vertebral column and the circumstances under which this can also lead to spinal cord injury. Further study was devoted to the assessment of the force with which a certain part of the cervical vertebral column resists the injuring forces and in what manner it contributes to the final state of injury. The results of this research made it possible to lay down the principles of prevention from as well as treatment of the cervical vertebral column and spinal cord injury.

A teratoma of the third ventricle of the brain.

A report is presented here of the total extirpation of a teratoma located in the third ventricle of a boy of eight. Since the tumour was made up of mature tissues (adult teratoma), its extirpation may be regarded as a cure. Although there are a few exceptions to the rule, other tumours located in the third ventricle of brain are mostly malignant, and they penetrate the tissues which constitute the wall of the third ventricle. For that reason the effects of a radical operation are doubtful. The adult teratoma is an exception. A tumour of this kind should be extirpated as a whole and removed from the third ventricle of brain.