Occasionally, there can be a complete absence of ossification in one or more vertebrae. In the skull, individual bones may calcify only at their centers. Another unusual radiographic feature is bony spurs that protrude laterally from the shafts of the ulnae and fibulae. Despite the considerable patient-to-patient variability and the diversity of radiographic findings, the X-ray can be considered diagnostic. Infantile hypophosphatasia
Infantile hypophosphatasia presents in the first 6 months of life, with the onset of poor feeding and inadequate weight gain. Clinical manifestations of rickets often appear at this time. Although cranial sutures appear to be wide, this reflects hypomineralization of the skull, and there is often “functional” craniosynostosis. If the patient survives infancy, these sutures can permanently fuse. Defects in the chest, such as flail chest resulting from rib fractures, lead to respiratory compromise and pneumonia. Elevated calcium in the blood (hypercalcemia) and urine (hypercalcenuria) are also common, and may explain the renal problems and recurrent vomiting seen is this disease.Radiographic features in infants are generally less severe than those seen in perinatal hypophosphatasia. In the long bones, there is an abrupt change from a normal appearance in the shaft (diaphysis) to uncalcified regions near the ends (metaphysis), which suggests the occurrence of an abrupt metabolic change. In addition, serial radiography studies suggest that defects in skeletal mineralization (i.e. rickets) persist and become more generalized. Mortality is estimated to be 50% in the first year of life. Childhood hypophosphatasia
Hypophosphatasia in childhood has variable clinical expression.
Four Evangelists – Matthew, Mark, Luke, and John
Four Doctors of Western Church – Saint Gregory the Great, Saint Ambrose, Saint Augustine, and Saint Jerome
Four Doctors of Eastern Church – Saint John Chrysostom, Saint Basil the Great, and Gregory of Nazianzus and Saint Athanasius
Four Galilean moons of Jupiter – Io, Europa, Ganymede, and Callisto
The Gang of Four was a Chinese communist political faction. The Fantastic Four: Mr. Fantastic, The Invisible Woman, The Human Torch, The Thing. The Teenage Mutant Ninja Turtles: Leonardo, Michelangelo, Donatello, Raphael
The Beatles were also known as the "Fab Four": John Lennon, Paul McCartney, George Harrison, Ringo Starr. Gang of Four is a British post-punk rock band formed in the late 1970s. Four rivers in the Garden of Eden (Genesis 2:10–14): Pishon (perhaps the Jaxartes or Syr Darya), Gihon (perhaps the Oxus or Amu Darya), Hiddekel (Tigris), and Prat (Euphrates). There are also four years in a single Olympiad (duration between the Olympic Games). Many major international sports competitions follow this cycle, among them the FIFA World Cup and its womens version, the FIBA World Championships for men and women, and the Rugby World Cup. There are four limbs on the human body. Four Houses of Hogwarts in the Harry Potter series: Gryffindor, Hufflepuff, Ravenclaw, Slytherin. Four known continents of the world in the A Song of Ice and Fire series: Westeros, Essos, Sothoryos, Ulthos. Each Grand Prix in Nintendos Mario Kart series is divided into four cups and each cup is divided into four courses.