Macrocephaly is a condition in which the human head is abnormally large; this includes the scalp, the cranial bone, and the contents of the cranium. It may be pathological or benign, even a familial genetic characteristic. People diagnosed with macrocephaly will have further testing done to determine if the syndrome is accompanied by any other disorders. Those with benign or familial macrocephaly are considered to have megalencephaly, another form of macrocephaly that will not result in the development of neurological disorders in the patient.
In histology, osteoid is the unmineralized, organic portion of the bone matrix that forms prior to the maturation of bone tissue. Osteoblasts begin the process of forming bone tissue by secreting the osteoid as several specific proteins. When the osteoid becomes mineralized, it and the adjacent bone cells have developed into new bone tissue.
A bone fracture is a medical condition in which there is a partial or complete break in the continuity of the bone. In more severe cases, the bone may be broken into several pieces. A bone fracture may be the result of high force impact or stress, or a minimal trauma injury as a result of certain medical conditions that weaken the bones, such as osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta, where the fracture is then properly termed a pathologic fracture.
Osteogenesis imperfecta (OI), also known as brittle bone disease, is a group of genetic disorders that mainly affect the bones. It results in bones that break easily. The severity may be mild to severe. Other symptoms may include a blue tinge to the whites of the eye, short height, loose joints, hearing loss, breathing problems and problems with the teeth. Complications may include cervical artery dissection and aortic dissection.
Ossification in bone remodeling is the process of laying down new bone material by cells called osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in the formation of normal, healthy bone tissue: Intramembranous ossification is the direct laying down of bone into the primitive connective tissue (mesenchyme), while endochondral ossification involves cartilage as a precursor. In fracture healing, endochondral osteogenesis is the most commonly occurring process, for example in fractures of long bones treated by plaster of Paris, whereas fractures treated by open reduction and internal fixation with metal plates, screws, pins, rods and nails may heal by intramembranous osteogenesis.
A greenstick fracture is a fracture in a young, soft bone in which the bone bends and breaks. Greenstick fractures occur most often during infancy and childhood when bones are soft. The name is by analogy with green wood which similarly breaks on the outside when bent.
The Ilizarov apparatus is a type of external fixation used in orthopedic surgery to lengthen or reshape limb bones; as a limb-sparing technique to treat complex and/or open bone fractures; and in cases of infected nonunions of bones that are not amenable with other techniques. It is named after the orthopedic surgeon Gavriil Abramovich Ilizarov from the Soviet Union, who pioneered the technique.
A skull fracture is a break in one or more of the eight bones that form the cranial portion of the skull, usually occurring as a result of blunt force trauma. If the force of the impact is excessive, the bone may fracture at or near the site of the impact and cause damage to the underlying structures within the skull such as the membranes, blood vessels, and brain.
Child abuse or child maltreatment is physical, sexual, and/or psychological maltreatment or neglect of a child or children, especially by a parent or a caregiver. Child abuse may include any act or failure to act by a parent or a caregiver that results in actual or potential harm to a child, and can occur in a child's home, or in the organizations, schools or communities the child interacts with.
Collagen, type I, alpha 1, also known as alpha-1 type I collagen, is a protein that in humans is encoded by the COL1A1 gene. COL1A1 encodes the major component of type I collagen, the fibrillar collagen found in most connective tissues, including cartilage.
Dentinogenesis imperfecta (DI) is a genetic disorder of tooth development. This condition is a type of dentin dysplasia that causes teeth to be discolored and translucent giving teeth an opalescent sheen. Although genetic factors are the main contributor for the disease, any environmental or systemic upset that impedes calcification or metabolisation of calcium can also result in anomalous dentine.
Wormian bones, also known as intrasutural bones or sutural bones, are extra bone pieces that can occur within a suture (joint) in the skull. These are irregular isolated bones that can appear in addition to the usual centres of ossification of the skull and, although unusual, are not rare. They occur most frequently in the course of the lambdoid suture, which is more tortuous than other sutures. They are also occasionally seen within the sagittal and coronal sutures. A large wormian bone at lambda is often called an Inca bone, due to the relatively high frequency of occurrence in Peruvian mummies. Another specific Wormian bone, the pterion ossicle, sometimes exists between the sphenoidal angle of the parietal bone and the great wing of the sphenoid bone. They tend to vary in size and can be found on either side of the skull. Usually, not more than several are found in a single individual, but more than one hundred have been once found in the skull of a hydrocephalic adult.
Osteochondrodysplasia is a general term for a disorder of the development (dysplasia) of bone ("osteo") and cartilage ("chondro").
A compression fracture is a collapse of a vertebra. It may be due to trauma or due to a weakening of the vertebra. This weakening is seen in patients with osteoporosis or osteogenesis imperfecta, lytic lesions from metastatic or primary tumors, or infection. In healthy patients, it is most often seen in individuals suffering extreme vertical shocks, such as ejecting from an ejection seat. Seen in lateral views in plain x-ray films, compression fractures of the spine characteristically appear as wedge deformities, with greater loss of height anteriorly than posteriorly and intact pedicles in the anteroposterior view.
A pathologic fracture is a bone fracture caused by weakness of the bone structure that leads to decrease mechanical resistance to normal mechanical loads. This process is most commonly due to osteoporosis, but may also be due to other pathologies such as: cancer, infection, inherited bone disorders, or a bone cyst. Only a small number of conditions are commonly responsible for pathological fractures, including osteoporosis, osteomalacia, Paget's disease, osteitis, osteogenesis imperfecta, benign bone tumours and cysts, secondary malignant bone tumours and primary malignant bone tumours.
Toddler's fractures are bone fractures of the distal (lower) part of the shin bone (tibia) in toddlers and other young children. The fracture is found in the distal two thirds of the tibia in 95% of cases, is undisplaced and has a spiral pattern. It occurs after low-energy trauma, sometimes with a rotational component.
Juvenile osteoporosis is osteoporosis in children and adolescents. Osteoporosis is rare in children and adolescents. When it occurs, it is usually secondary to some other condition, e.g. osteogenesis imperfecta, rickets, eating disorders or arthritis. In some cases, there is no known cause and it is called idiopathic juvenile osteoporosis. Idiopathic juvenile osteoporosis usually goes away spontaneously.
A child bone fracture or a pediatric fracture is a medical condition in which a bone of a child is cracked or broken. About 15% of all injuries in children are fracture injuries. Bone fractures in children are different from adult bone fractures because a child's bones are still growing. Also, more consideration needs to be taken when a child fractures a bone since it will affect the child in his or her growth.
Sean Clinch Stephenson was an American therapist, self-help author and motivational speaker. Because he was born with osteogenesis imperfecta, Stephenson stood three feet tall, had fragile bones, and used a wheelchair.
