- Type 4 osteogenesis imperfecta is more severe
than type 1 but less severe than type 3. Frac-
tures are most common before PUBERTY. Hearing
loss begins in early childhood and is often pro-
found.
The bones of infants who have osteogenesis
imperfecta are very fragile and may fracture with
the slightest contact, even that of picking up or
holding the infant. Nonetheless, touch and hold-
ing are very important for proper development.
The health-care team can provide suggestions to
minimize the risk for fracture. Treatment for frac-
ture is generally conservative, targeting a balance
between immobilizing the fracture long enough
for it to heal and allowing normal MUSCLEfunction
as quickly as possible. Physical activity helps
strengthen muscles and bone, which in turn mini-
mizes fractures. The most numerous fractures
occur during childhood when the bones are grow-
ing and thus have lower mineral content. The risk
for fracture is lifelong, however, and may increase
in women after MENOPAUSEwhen BONE DENSITYnat-
urally declines. There are as yet no treatments to
overcome the collagen deficiencies of osteogenesis
imperfecta.
See also GENETIC DISORDERS; INHERITANCE PATTERN.
osteomalacia Softening of the bones that most
often occurs as a result of vitamin D deficiency or
abnormalities in vitamin D METABOLISMthat pre-
vent mineral crystals from accumulating in the
BONEtissue. Vitamin D is essential to bone remod-
eling and the bone’s ability to draw calcium and
other minerals from the BLOODcirculation.
Osteomalacia develops when there is insuffi-
cient mineralization of the osteoid, a collagen-
based substance the osteoblasts (bone-forming
cells) produce. Instead of hardening into the bone
matrix, the osteoid simply accumulates within the
bone. Other causes of osteomalacia include
chronic LIVER disease, END-STAGE RENAL DISEASE
(ESRD), hypophosphatemia (insufficient phospho-
rus intake or metabolism), fluoride toxicity, and
excessive antacid consumption.
Symptoms of osteomalacia include
- bone PAIN, especially in the hips
- numbness or tingling around the lips
- MUSCLEweakness
- pathologic bone FRACTURE(fractures that occur
with minimal trauma or spontaneously)
Bone biopsy provides the conclusive diagnosis.
Treatment is usually intense vitamin D supple-
mentation until bone mineralization returns to
normal. Depending on the underlying cause of the
osteomalacia, some people may also need to take
phosphorus supplements. Most people recover
fully with appropriate treatment.
See also ANTACIDS; CALCIUM AND BONE HEALTH;
MINERALS AND HEALTH; OSTEOPENIA; OSTEOPETROSIS;
OSTEOPOROSIS; RICKETS; VITAMINS AND HEALTH.osteomyelitis An INFECTIONof the BONE. Typically
the infection starts elsewhere in the body and
spreads through the BLOODcirculation to the bone,
though may originate in the bone as a complica-
tion of surgery on the bone (such as open reduc-
tion of a FRACTUREorJOINT REPLACEMENT). Bacterial
infection causes most osteomyelitis, though other
pathogens such as fungi (yeast) may also be
responsible. The long bones in the leg are the most
common locations for osteomyelitis in children;
osteomyelitis in adults tends to settle in the hip or
pelvis.Symptoms and Diagnostic Path
Symptoms of osteomyelitis include- PAINfrom the area of the infection
- swelling in the area of the infection
- FEVER
- generalized discomfort and sense of not feeling
well
The diagnostic path begins with a comprehen-
sive medical examination and PERSONAL HEALTH HIS-
TORYto identify any recent infections, injuries, or
surgeries. X-RAYmay show the area of infection,
though other imaging procedures such as bone
scan or MAGNETIC RESONANCE IMAGING (MRI) often
produce more complete information. Biopsy of the
site confirms the diagnosis and can identify the
responsible PATHOGEN. Blood tests such as completeosteomyelitis 343