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Bone and joint infections may occur at any age but are more common
in children than adults. Optimal management requires early diagnosis and
aggressive initial treatment to prevent disabling sequelae. This
is usually best achieved with care being provided by a multidisciplinary team
of pediatricians and orthopedic surgeons experienced in the specific
issues encountered in care of growing children. Soft tissue infections occur
more frequently than skeletal infections but they are generally
simpler to diagnose and treat with antibiotic therapy. This chapter
reviews the approach to diagnosis and management of these disorders
in children. Soft tissue infections in children, generally less
difficult to diagnose and treat than skeletal infections, remain
important because of their greater frequency of occurrence and the
need for antibiotic therapy, occasionally in conjunction with hospitalization.
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Acute Hematogenous Osteomyelitis
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Acute hematogenous osteomyelitis (AHO) is a disease of young
children. The majority of cases occur before 5 years of age with
up to one third occurring in children younger than 2 years of age.1,2 There
is a male predilection, with males outnumbering females in most
published series by approximately 2:1.1-5 However,
in a more recently published series, males accounted for 52% of
the patients.6 There is frequently a history of some
type of minor blunt trauma2,7 or intercurrent illness,
such as an upper respiratory tract infection.8 Other
risk factors for AHO include immunodeficiency states, sickle cell
anemia, and indwelling vascular catheters. In some areas of the
United States, the incidence of osteoarticular diseases including
AHO has increased with the emergence of community-associated methicillin-resistant Staphylococcus
aureus (CA-MRSA).6
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The majority of bone infections in children are of hematogenous
origin.2 The vascular anatomy of long bones in
children underlies the predilection for localization of blood-borne
bacteria. In children, unlike in adults and young infants, the blood
supply of the epiphysis is separate from the metaphysis.10 The
nutrient artery to the metaphysis empties into a system of venous
sinusoids in which sluggish flow presumably facilitates deposition
of bacteria. During the cellulitic phase of acute
osteomyelitis infection originates on the venous side of the system
and then spreads to the nutrient artery, causing thrombosis of the
nutrient artery.9 The resultant ischemia prevents
host defense mechanisms from reaching the area and allows bacterial
proliferation. Formation of an abscess can then occur which can
rupture into the subperiosteal space with subsequent elevation of
the periosteum, which is loosely adherent in children. If infection
is uncontrolled, purulent material may extend up and down the diaphysis
and circumferentially around the bone (see Figure
234-1). In areas in which the metaphysis is intra-articular,
such as the hip and shoulder, the intraosseous abscess may rupture
into the joint resulting in septic arthritis.9 In newborns
and young infants, blood vessels connect the metaphysis and epiphysis,
and rupture of pus ...