Sacroiliac Joint: The immovable joint formed by the lateral surfaces of the SACRUM and ILIUM.Sacroiliitis: Inflammation of the SACROILIAC JOINT. It is characterized by lower back pain, especially upon walking, fever, UVEITIS; PSORIASIS; and decreased range of motion. Many factors are associated with and cause sacroiliitis including infection; injury to spine, lower back, and pelvis; DEGENERATIVE ARTHRITIS; and pregnancy.Spondylarthritis: Inflammation of the joints of the SPINE, the intervertebral articulations.Joint DiseasesSpondylitis, Ankylosing: A chronic inflammatory condition affecting the axial joints, such as the SACROILIAC JOINT and other intervertebral or costovertebral joints. It occurs predominantly in young males and is characterized by pain and stiffness of joints (ANKYLOSIS) with inflammation at tendon insertions.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.Injections, Intra-Articular: Methods of delivering drugs into a joint space.Pelvic Bones: Bones that constitute each half of the pelvic girdle in VERTEBRATES, formed by fusion of the ILIUM; ISCHIUM; and PUBIC BONE.Tuberculosis, Osteoarticular: Tuberculosis of the bones or joints.Joints: Also known as articulations, these are points of connection between the ends of certain separate bones, or where the borders of other bones are juxtaposed.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.Nerve Block: Interruption of NEURAL CONDUCTION in peripheral nerves or nerve trunks by the injection of a local anesthetic agent (e.g., LIDOCAINE; PHENOL; BOTULINUM TOXINS) to manage or treat pain.Back Pain: Acute or chronic pain located in the posterior regions of the THORAX; LUMBOSACRAL REGION; or the adjacent regions.Ilium: The largest of three bones that make up each half of the pelvic girdle.Pelvic Girdle Pain: Discomfort associated with the bones that make up the pelvic girdle. It occurs frequently during pregnancy.Manipulation, Orthopedic: The planned and carefully managed manual movement of the musculoskeletal system, extremities, and spine to produce increased motion. The term is sometimes used to denote a precise sequence of movements of a joint to determine the presence of disease or to reduce a dislocation. In the case of fractures, orthopedic manipulation can produce better position and alignment of the fracture. (From Blauvelt & Nelson, A Manual of Orthopaedic Terminology, 5th ed, p264)Pubic Bone: A bone that forms the lower and anterior part of each side of the hip bone.Pain, Referred: A type of pain that is perceived in an area away from the site where the pain arises, such as facial pain caused by lesion of the VAGUS NERVE, or throat problem generating referred pain in the ear.Spondylitis: Inflammation of the SPINE. This includes both arthritic and non-arthritic conditions.Zygapophyseal Joint: The joint that occurs between facets of the interior and superior articular processes of adjacent VERTEBRAE.Arthritis, Infectious: Arthritis caused by BACTERIA; RICKETTSIA; MYCOPLASMA; VIRUSES; FUNGI; or PARASITES.Sciatica: A condition characterized by pain radiating from the back into the buttock and posterior/lateral aspects of the leg. Sciatica may be a manifestation of SCIATIC NEUROPATHY; RADICULOPATHY (involving the SPINAL NERVE ROOTS; L4, L5, S1, or S2, often associated with INTERVERTEBRAL DISK DISPLACEMENT); or lesions of the CAUDA EQUINA.ArthritisLumbosacral 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.Spine: The spinal or vertebral column.Anesthetics, Local: Drugs that block nerve conduction when applied locally to nerve tissue in appropriate concentrations. They act on any part of the nervous system and on every type of nerve fiber. In contact with a nerve trunk, these anesthetics can cause both sensory and motor paralysis in the innervated area. Their action is completely reversible. (From Gilman AG, et. al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed) Nearly all local anesthetics act by reducing the tendency of voltage-dependent sodium channels to activate.HLA-B27 Antigen: A specific HLA-B surface antigen subtype. Members of this subtype contain alpha chains that are encoded by the HLA-B*27 allele family.Osteitis: Inflammation of the bone.Knee Joint: A synovial hinge connection formed between the bones of the FEMUR; TIBIA; and PATELLA.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.Lumbar Vertebrae: VERTEBRAE in the region of the lower BACK below the THORACIC VERTEBRAE and above the SACRAL VERTEBRAE.Anesthesia, Local: A blocking of nerve conduction to a specific area by an injection of an anesthetic agent.Pain Management: A form of therapy that employs a coordinated and interdisciplinary approach for easing the suffering and improving the quality of life of those experiencing pain.Biomechanical Phenomena: The properties, processes, and behavior of biological systems under the action of mechanical forces.Population Groups: Individuals classified according to their sex, racial origin, religion, common place of living, financial or social status, or some other cultural or behavioral attribute. (UMLS, 2003)Temporomandibular Joint Dysfunction Syndrome: A symptom complex consisting of pain, muscle tenderness, clicking in the joint, and limitation or alteration of mandibular movement. The symptoms are subjective and manifested primarily in the masticatory muscles rather than the temporomandibular joint itself. Etiologic factors are uncertain but include occlusal dysharmony and psychophysiologic factors.Temporomandibular Joint Disorders: A variety of conditions affecting the anatomic and functional characteristics of the temporomandibular joint. Factors contributing to the complexity of temporomandibular diseases are its relation to dentition and mastication and the symptomatic effects in other areas which account for referred pain to the joint and the difficulties in applying traditional diagnostic procedures to temporomandibular joint pathology where tissue is rarely obtained and x-rays are often inadequate or nonspecific. Common diseases are developmental abnormalities, trauma, subluxation, luxation, arthritis, and neoplasia. (From Thoma's Oral Pathology, 6th ed, pp577-600)Nonprescription Drugs: Medicines that can be sold legally without a DRUG PRESCRIPTION.Facial Pain: Pain in the facial region including orofacial pain and craniofacial pain. Associated conditions include local inflammatory and neoplastic disorders and neuralgic syndromes involving the trigeminal, facial, and glossopharyngeal nerves. Conditions which feature recurrent or persistent facial pain as the primary manifestation of disease are referred to as FACIAL PAIN SYNDROMES.Antitussive Agents: Agents that suppress cough. They act centrally on the medullary cough center. EXPECTORANTS, also used in the treatment of cough, act locally.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Back: The rear surface of an upright primate from the shoulders to the hip, or the dorsal surface of tetrapods.Electromyography: Recording of the changes in electric potential of muscle by means of surface or needle electrodes.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Sacrococcygeal Region: The body region between (and flanking) the SACRUM and COCCYX.Reflex: An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.MedlinePlus: NATIONAL LIBRARY OF MEDICINE service for health professionals and consumers. It links extensive information from the National Institutes of Health and other reviewed sources of information on specific diseases and conditions.Massage: The systematic and methodical manipulations of body tissues best performed with the hands for the purpose of affecting the nervous and muscular systems and the general circulation.Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Genomic Structural Variation: Contiguous large-scale (1000-400,000 basepairs) differences in the genomic DNA between individuals, due to SEQUENCE DELETION; SEQUENCE INSERTION; or SEQUENCE INVERSION.Evidence-Based Medicine: An approach of practicing medicine with the goal to improve and evaluate patient care. It requires the judicious integration of best research evidence with the patient's values to make decisions about medical care. This method is to help physicians make proper diagnosis, devise best testing plan, choose best treatment and methods of disease prevention, as well as develop guidelines for large groups of patients with the same disease. (from JAMA 296 (9), 2006)Titanium: A dark-gray, metallic element of widespread distribution but occurring in small amounts; atomic number, 22; atomic weight, 47.90; symbol, Ti; specific gravity, 4.5; used for fixation of fractures. (Dorland, 28th ed)Arthralgia: Pain in the joint.