Hyperostosis, Diffuse Idiopathic Skeletal: A disease of elderly men characterized by large osteophytes that bridge vertebrae and ossification of ligaments and tendon insertions.Hyperostosis: Increase in the mass of bone per unit volume.Acquired Hyperostosis Syndrome: Syndrome consisting of SYNOVITIS; ACNE CONGLOBATA; PALMOPLANTAR PUSTULOSIS; HYPEROSTOSIS; and OSTEITIS. The most common site of the disease is the upper anterior chest wall, characterized by predominantly osteosclerotic lesions, hyperostosis, and arthritis of the adjacent joints. The association of sterile inflammatory bone lesions and neutrophilic skin eruptions is indicative of this syndrome.Hyperostosis Frontalis Interna: Thickening of the inner table of the frontal bone, which may be associated with hypertrichosis and obesity. It most commonly affects women near menopause.Hyperostosis, Sternocostoclavicular: A rare, benign rheumatologic disorder or syndrome characterized by hyperostosis and soft tissue ossification between the clavicles and the anterior part of the upper ribs. It is often associated with the dermatologic disorder palmoplantar pustulosis, particularly in Japan. Careful diagnosis is required to distinguish it from psoriatic arthritis, OSTEITIS DEFORMANS, and other diseases. Spondylitis of pustulosis palmaris et plantaris is one of the possible causes; also, evidence suggests one origin may be bone infection. Bone imaging is especially useful for diagnosis. It was originally described by Sonozaki in 1974.Neuroendocrine Cells: Specialized NEURONS that produce hormones, such as NEUROPEPTIDES or BIOGENIC AMINES. They generally are in the NERVOUS SYSTEM, such as HYPOTHALAMUS, but can be found in other organs or systems. These neurons contain dense neurosecretory granules and PROPROTEIN CONVERTASES allowing the rapidly release of NEUROHORMONES into the blood circulation upon stimulation.Paleopathology: The study of disease in prehistoric times as revealed in bones, mummies, and archaeologic artifacts.Spinal Osteophytosis: Outgrowth of immature bony processes or bone spurs (OSTEOPHYTE) from the VERTEBRAE, reflecting the presence of degenerative disease and calcification. It commonly occurs in cervical and lumbar SPONDYLOSIS.Multiple Pulmonary Nodules: A number of small lung lesions characterized by small round masses of 2- to 3-mm in diameter. They are usually detected by chest CT scans (COMPUTED TOMOGRAPHY, X-RAY). Such nodules can be associated with metastases of malignancies inside or outside the lung, benign granulomas, or other lesions.Longitudinal Ligaments: Two extensive fibrous bands running the length of the vertebral column. The anterior longitudinal ligament (ligamentum longitudinale anterius; lacertus medius) interconnects the anterior surfaces of the vertebral bodies; the posterior longitudinal ligament (ligamentum longitudinale posterius) interconnects the posterior surfaces. The commonest clinical consideration is OSSIFICATION OF POSTERIOR LONGITUDINAL LIGAMENT. (From Stedman, 25th ed)Cervical Vertebrae: The first seven VERTEBRAE of the SPINAL COLUMN, which correspond to the VERTEBRAE of the NECK.Exostoses: Benign hypertrophy that projects outward from the surface of bone, often containing a cartilaginous component.Melorheostosis: A form of osteosclerosis extending in a linear track mainly through one of the long bones of the upper and lower limbs.Ankylosis: Fixation and immobility of a joint.Hyperplasia: An increase in the number of cells in a tissue or organ without tumor formation. It differs from HYPERTROPHY, which is an increase in bulk without an increase in the number of cells.Papilloma, Inverted: A mucosal tumor of the urinary bladder or nasal cavity in which proliferating epithelium is invaginated beneath the surface and is more smoothly rounded than in other papillomas. (Stedman, 25th ed)Osteitis: Inflammation of the bone.Hyperostosis, Cortical, Congenital: A disease of young infants characterized by soft tissue swellings over the affected bones, fever, and irritability, and marked by periods of remission and exacerbation. (Dorland, 27th ed)Paranasal Sinuses: Air-filled spaces located within the bones around the NASAL CAVITY. They are extensions of the nasal cavity and lined by the ciliated NASAL MUCOSA. Each sinus is named for the cranial bone in which it is located, such as the ETHMOID SINUS; the FRONTAL SINUS; the MAXILLARY SINUS; and the SPHENOID SINUS.Skull: The SKELETON of the HEAD including the FACIAL BONES and the bones enclosing the BRAIN.