Spinal Dysraphism: Congenital defects of closure of one or more vertebral arches, which may be associated with malformations of the spinal cord, nerve roots, congenital fibrous bands, lipomas, and congenital cysts. These malformations range from mild (e.g., SPINA BIFIDA OCCULTA) to severe, including rachischisis where there is complete failure of neural tube and spinal cord fusion, resulting in exposure of the spinal cord at the surface. Spinal dysraphism includes all forms of spina bifida. The open form is called SPINA BIFIDA CYSTICA and the closed form is SPINA BIFIDA OCCULTA. (From Joynt, Clinical Neurology, 1992, Ch55, p34)Spina Bifida Occulta: A common congenital midline defect of fusion of the vertebral arch without protrusion of the spinal cord or meninges. The lesion is also covered by skin. L5 and S1 are the most common vertebrae involved. The condition may be associated with an overlying area of hyperpigmented skin, a dermal sinus, or an abnormal patch of hair. The majority of individuals with this malformation are asymptomatic although there is an increased incidence of tethered cord syndrome and lumbar SPONDYLOSIS. (From Joynt, Clinical Neurology, 1992, Ch55, p34)Pentalogy of Cantrell: Rare congenital deformity syndrome characterized by a combination of five anomalies as a result of neural tube defect. The five anomalies are a midline supraumbilical abdominal wall defect (e.g., OMPHALOCELE), a lower STERNUM defect, a congenital intracardiac defect, an anterior DIAPHRAGM defect, and a diaphragmatic PERICARDIUM defect (e.g., PERICARDIAL EFFUSION). Variants with incomplete and variable combinations of the defects are known. ECTOPIA CORDIS; CLEFT LIP; and CLEFT PALATE are often associated with the syndrome.Acro-Osteolysis: A condition with congenital and acquired forms causing recurrent ulcers in the fingers and toes. The congenital form exhibits autosomal dominant inheritance; the acquired form is found in workers who handle VINYL CHLORIDE. When acro-osteolysis is accompanied by generalized OSTEOPOROSIS and skull deformations, it is called HAJDU-CHENEY SYNDROME.Meningocele: A congenital or acquired protrusion of the meninges, unaccompanied by neural tissue, through a bony defect in the skull or vertebral column.Neural Tube Defects: Congenital malformations of the central nervous system and adjacent structures related to defective neural tube closure during the first trimester of pregnancy generally occurring between days 18-29 of gestation. Ectodermal and mesodermal malformations (mainly involving the skull and vertebrae) may occur as a result of defects of neural tube closure. (From Joynt, Clinical Neurology, 1992, Ch55, pp31-41)Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Lipoma: A benign tumor composed of fat cells (ADIPOCYTES). It can be surrounded by a thin layer of connective tissue (encapsulated), or diffuse without the capsule.Spinal Cord Injuries: Penetrating and non-penetrating injuries to the spinal cord resulting from traumatic external forces (e.g., WOUNDS, GUNSHOT; WHIPLASH INJURIES; etc.).