Lumbosacral Region: Region of the back including the LUMBAR VERTEBRAE, SACRUM, and nearby structures.Sacrum: Five fused VERTEBRAE forming a triangle-shaped structure at the back of the PELVIS. It articulates superiorly with the LUMBAR VERTEBRAE, inferiorly with the COCCYX, and anteriorly with the ILIUM of the PELVIS. The sacrum strengthens and stabilizes the PELVIS.Lumbosacral Plexus: The lumbar and sacral plexuses taken together. The fibers of the lumbosacral plexus originate in the lumbar and upper sacral spinal cord (L1 to S3) and innervate the lower extremities.Lumbar Vertebrae: VERTEBRAE in the region of the lower BACK below the THORACIC VERTEBRAE and above the SACRAL VERTEBRAE.Spinal Nerve Roots: Paired bundles of NERVE FIBERS entering and leaving the SPINAL CORD at each segment. The dorsal and ventral nerve roots join to form the mixed segmental spinal nerves. The dorsal roots are generally afferent, formed by the central projections of the spinal (dorsal root) ganglia sensory cells, and the ventral roots are efferent, comprising the axons of spinal motor and PREGANGLIONIC AUTONOMIC FIBERS.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Buttocks: Either of two fleshy protuberances at the lower posterior section of the trunk or HIP in humans and primate on which a person or animal sits, consisting of gluteal MUSCLES and fat.Neurofibrosarcoma: A malignant tumor that arises from small cutaneous nerves, is locally aggressive, and has a potential for metastasis. Characteristic histopathologic features include proliferating atypical spindle cells with slender wavy and pointed nuclei, hypocellular areas, and areas featuring organized whorls of fibroblastic proliferation. The most common primary sites are the extremities, retroperitoneum, and trunk. These tumors tend to present in childhood, often in association with NEUROFIBROMATOSIS 1. (From DeVita et al., Cancer: Principles & Practice of Oncology, 5th ed, p1662; Mayo Clin Proc 1990 Feb;65(2):164-72)Thigh: The portion of the leg in humans and other animals found between the HIP and KNEE.Choroid Plexus: A villous structure of tangled masses of BLOOD VESSELS contained within the third, lateral, and fourth ventricles of the BRAIN. It regulates part of the production and composition of CEREBROSPINAL FLUID.Diagnosis-Related Groups: A system for classifying patient care by relating common characteristics such as diagnosis, treatment, and age to an expected consumption of hospital resources and length of stay. Its purpose is to provide a framework for specifying case mix and to reduce hospital costs and reimbursements and it forms the cornerstone of the prospective payment system.International Classification of Diseases: A system of categories to which morbid entries are assigned according to established criteria. Included is the entire range of conditions in a manageable number of categories, grouped to facilitate mortality reporting. It is produced by the World Health Organization (From ICD-10, p1). The Clinical Modifications, produced by the UNITED STATES DEPT. OF HEALTH AND HUMAN SERVICES, are larger extensions used for morbidity and general epidemiological purposes, primarily in the U.S.Dry Eye Syndromes: Corneal and conjunctival dryness due to deficient tear production, predominantly in menopausal and post-menopausal women. Filamentary keratitis or erosion of the conjunctival and corneal epithelium may be caused by these disorders. Sensation of the presence of a foreign body in the eye and burning of the eyes may occur.Clinical Coding: Process of substituting a symbol or code for a term such as a diagnosis or procedure. (from Slee's Health Care Terms, 3d ed.)Chronology as Topic: The temporal sequence of events that have occurred.Palpation: Application of fingers with light pressure to the surface of the body to determine consistence of parts beneath in physical diagnosis; includes palpation for determining the outlines of organs.ChalconeBooksNoble Gases: Elements that constitute group 18 (formerly the zero group) of the periodic table. They are gases that generally do not react chemically.Musculoskeletal Diseases: Diseases of the muscles and their associated ligaments and other connective tissue and of the bones and cartilage viewed collectively.Musculoskeletal System: The MUSCLES, bones (BONE AND BONES), and CARTILAGE of the body.Maze Learning: Learning the correct route through a maze to obtain reinforcement. It is used for human or animal populations. (Thesaurus of Psychological Index Terms, 6th ed)MississippiNeurosurgery: A surgical specialty concerned with the treatment of diseases and disorders of the brain, spinal cord, and peripheral and sympathetic nervous system.Veterinary Medicine: The medical science concerned with the prevention, diagnosis, and treatment of diseases in animals.Neurology: A medical specialty concerned with the study of the structures, functions, and diseases of the nervous system.Neurosurgical Procedures: Surgery performed on the nervous system or its parts.Education, Veterinary: Use for general articles concerning veterinary medical education.Computing Methodologies: Computer-assisted analysis and processing of problems in a particular area.Low Back Pain: Acute or chronic pain in the lumbar or sacral regions, which may be associated with musculo-ligamentous SPRAINS AND STRAINS; INTERVERTEBRAL DISK DISPLACEMENT; and other conditions.Chronic Pain: Aching sensation that persists for more than a few months. It may or may not be associated with trauma or disease, and may persist after the initial injury has healed. Its localization, character, and timing are more vague than with acute pain.Cross-Over Studies: Studies comparing two or more treatments or interventions in which the subjects or patients, upon completion of the course of one treatment, are switched to another. In the case of two treatments, A and B, half the subjects are randomly allocated to receive these in the order A, B and half to receive them in the order B, A. A criticism of this design is that effects of the first treatment may carry over into the period when the second is given. (Last, A Dictionary of Epidemiology, 2d ed)Pain Measurement: Scales, questionnaires, tests, and other methods used to assess pain severity and duration in patients or experimental animals to aid in diagnosis, therapy, and physiological studies.Back Pain: Acute or chronic pain located in the posterior regions of the THORAX; LUMBOSACRAL REGION; or the adjacent regions.Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Chronic Disease: Diseases which have one or more of the following characteristics: they are permanent, leave residual disability, are caused by nonreversible pathological alteration, require special training of the patient for rehabilitation, or may be expected to require a long period of supervision, observation, or care. (Dictionary of Health Services Management, 2d ed)Phthalimides: The imide of phthalic acids.Bell Palsy: A syndrome characterized by the acute onset of unilateral FACIAL PARALYSIS which progresses over a 2-5 day period. Weakness of the orbicularis oculi muscle and resulting incomplete eye closure may be associated with corneal injury. Pain behind the ear often precedes the onset of paralysis. This condition may be associated with HERPESVIRUS 1, HUMAN infection of the facial nerve. (Adams et al., Principles of Neurology, 6th ed, p1376)Lysine-tRNA Ligase: An enzyme that activates lysine with its specific transfer RNA. EC 188.8.131.52.Burning Mouth Syndrome: A group of painful oral symptoms associated with a burning or similar sensation. There is usually a significant organic component with a degree of functional overlay; it is not limited to the psychophysiologic group of disorders.Tetrahydrouridine: An inhibitor of nucleotide metabolism.Contusions: Injuries resulting in hemorrhage, usually manifested in the skin.Agar: A complex sulfated polymer of galactose units, extracted from Gelidium cartilagineum, Gracilaria confervoides, and related red algae. It is used as a gel in the preparation of solid culture media for microorganisms, as a bulk laxative, in making emulsions, and as a supporting medium for immunodiffusion and immunoelectrophoresis.Education, Dental: Use for articles concerning dental education in general.Students, Dental: Individuals enrolled a school of dentistry or a formal educational program in leading to a degree in dentistry.Schools, Dental: Educational institutions for individuals specializing in the field of dentistry.Dental Care: The total of dental diagnostic, preventive, and restorative services provided to meet the needs of a patient (from Illustrated Dictionary of Dentistry, 1982).IndiaCentral Nervous System: The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.Dentistry: The profession concerned with the teeth, oral cavity, and associated structures, and the diagnosis and treatment of their diseases including prevention and the restoration of defective and missing tissue.Materia Medica: Materials or substances used in the composition of traditional medical remedies. The use of this term in MeSH was formerly restricted to historical articles or those concerned with traditional medicine, but it can also refer to homeopathic remedies. Nosodes are specific types of homeopathic remedies prepared from causal agents or disease products.Hoarseness: An unnaturally deep or rough quality of voice.Medicine, Chinese Traditional: A system of traditional medicine which is based on the beliefs and practices of the Chinese culture.Pulmonary Stretch Receptors: Stretch receptors found in the bronchi and bronchioles. Pulmonary stretch receptors are sensors for a reflex which stops inspiration. In humans, the reflex is protective and is probably not activated during normal respiration.Sputum: Material coughed up from the lungs and expectorated via the mouth. It contains MUCUS, cellular debris, and microorganisms. It may also contain blood or pus.Drugs, Chinese Herbal: Chinese herbal or plant extracts which are used as drugs to treat diseases or promote general well-being. The concept does not include synthesized compounds manufactured in China.Bronchiectasis: Persistent abnormal dilatation of the bronchi.