Exostoses: Benign hypertrophy that projects outward from the surface of bone, often containing a cartilaginous component.Exostoses, Multiple Hereditary: Hereditary disorder transmitted by an autosomal dominant gene and characterized by multiple exostoses (multiple osteochondromas) near the ends of long bones. The genetic abnormality results in a defect in the osteoclastic activity at the metaphyseal ends of the bone during the remodeling process in childhood or early adolescence. The metaphyses develop benign, bony outgrowths often capped by cartilage. A small number undergo neoplastic transformation.Osteochondroma: A cartilage-capped benign tumor that often appears as a stalk on the surface of bone. It is probably a developmental malformation rather than a true neoplasm and is usually found in the metaphysis of the distal femur, proximal tibia, or proximal humerus. Osteochondroma is the most common of benign bone tumors.N-Acetylglucosaminyltransferases: Enzymes that catalyze the transfer of N-acetylglucosamine from a nucleoside diphosphate N-acetylglucosamine to an acceptor molecule which is frequently another carbohydrate. EC 2.4.1.-.Osteochondromatosis: A condition marked by the presence of multiple osteochondromas. (Dorland, 27th ed)Chondrosarcoma: A slowly growing malignant neoplasm derived from cartilage cells, occurring most frequently in pelvic bones or near the ends of long bones, in middle-aged and old people. Most chondrosarcomas arise de novo, but some may develop in a preexisting benign cartilaginous lesion or in patients with ENCHONDROMATOSIS. (Stedman, 25th ed)Ribs: A set of twelve curved bones which connect to the vertebral column posteriorly, and terminate anteriorly as costal cartilage. Together, they form a protective cage around the internal thoracic organs.Nail Diseases: Diseases of the nail plate and tissues surrounding it. The concept is limited to primates.Parietal Bone: One of a pair of irregularly shaped quadrilateral bones situated between the FRONTAL BONE and OCCIPITAL BONE, which together form the sides of the CRANIUM.Osteopoikilosis: An asymptomatic, autosomal dominant trait in which pea-sized sclerotic spots, prominent in the metaphyseal area, are accompanied by unique cutaneous lesions. These are yellowish papules or plaques with increased elastin content. (From Cecil Textbook of Medicine, 19th ed, pp1434-35)Langer-Giedion Syndrome: Autosomal dominant disorder characterized by cone-shaped epiphyses in the hands and multiple cartilaginous exostoses. INTELLECTUAL DISABILITY and abnormalities of chromosome 8 are often present. The exostoses in this syndrome appear identical to those of hereditary multiple exostoses (EXOSTOSES, HEREDITARY MULTIPLE).Transplant Donor Site: The body location or part from which tissue is taken for TRANSPLANTATION.Hallux: The innermost digit of the foot in PRIMATES.N-Acetylhexosaminyltransferases: Enzymes that catalyze the transfer of N-acetylhexosaminyl groups to an acceptor molecule which is frequently another carbohydrate. EC 2.4.1.Chromosomes, Human, Pair 8: A specific pair of GROUP C CHROMOSOMES of the human chromosome classification.Chromosomes, Human, Pair 11: A specific pair of GROUP C CHROMOSOMES of the human chromosome classification.Heparitin Sulfate: A heteropolysaccharide that is similar in structure to HEPARIN. It accumulates in individuals with MUCOPOLYSACCHARIDOSIS.Hemothorax: Hemorrhage within the pleural cavity.Periostitis: Inflammation of the periosteum. The condition is generally chronic, and is marked by tenderness and swelling of the bone and an aching pain. Acute periostitis is due to infection, is characterized by diffuse suppuration, severe pain, and constitutional symptoms, and usually results in necrosis. (Dorland, 27th ed)Ulna: The inner and longer bone of the FOREARM.Bone Neoplasms: Tumors or cancer located in bone tissue or specific BONES.Chromosomes, Human, Pair 19: A specific pair of GROUP F CHROMOSOMES of the human chromosome classification.