e. Maturity Rates. The time required for the bones to reach full development
varies for different parts of the skeleton. The skeleton matures somewhat earlier in the
female than in the male. The appearance of the epiphyseal centers of ossification and
their development can be followed by radiographic examination. Some appear at birth
while others appear from time to time during the first 15 years of life. Later, the
epiphysis and shaft of the bone unite. Ordinarily, all have united by the age of 25.
1-11. DESCRIPTIVE TERMINOLOGY
By reviewing the following terms, it will help you understand the discussion of
bones more easily.
a. Extremity. The distal or terminal portion of a bone. An arm or leg is also
referred to as an extremity.
b. Diaphysis, Shaft, or Body. The long, cylindrical part or the principal portion
of a bone.
c. Epiphyseal Zone. The area between the shaft and the end of a bone where
growth or an increase in length occurs.
d. Head. The expanded portion at the end of a bone, usually rounded.
e. Neck. The constricted portion of the bone next to the head.
f. Base. The expanded portion at the end of a bone opposite to its head.
g. Ramas. A branch of a bone.
Process. A general term for a projection.
Spine. A sharp projection.
Tubercle. A small, rounded, rough projection.
(4) Tuberosity. A large eminence (prominence or projection), usually
roughened, for the attachment of tendons or ligaments.
Styloid process. Like a stylus.
Trochanter. A very large, roughened process.
Crest. A projecting ridge of bone.