At the end of this lecture we should be able to:
Define acute OM.
Describe the natural history of the evolution of
Describe the clinical and radiographic features of
Define differential diagnosis of acute OM.
Outline Complications of acute OM.
Describe principles of management of children
with acute OM.
Osteomyelitis is a pyogenic
infection of the bone and bone
Age: 50% of cases occur in
Disease of childhood ; but can
occur in adults.
can reach the
From without (an infected
Direct spread (osteomyelitis
tibia from an overlying
chronic ulcer of the leg).
From neighboring focus of
infection such as Mastoiditis
from middle ear infection.
Open fracture of tibia.
This is a potential direct source of bacterial
Osteomyelitis is common in open fractures.
Right leg chronic
osteomyelitis in a 70-year-
old diabetic man.
He has had this wound
for 15 years.
Skin biopsy was negative
S. aureus has also
become an increasing
< 4 y)
Salmonella is a common
pathogen in patients with
children are prone to
infection with a variety of
fungi and bacteria.
The organism usually
reaches the blood
stream from a septic
General: lower vitality; convalescence
from fevers; e.g. measles.
Local : trauma
Sex: Male-to-female : 2:1 . Why?
Factors related to increased incidence in
males may include increased trauma due
to risk-taking behavior or other physical
activities that predispose to bone injury.
long bones (tibia,
sites are the lower
end of femur and
the upper end of
Vascular arrangement :
Blood flow slows down in
large sinusoidal veins.
Vulnerable to minor trauma,
as (site of attachment of
Lack of active phagocytosis
in metaphysis ; as compared
Poor collateral circulation
Anatomy of long bone and distribution of blood supply.
Bacteria pass through nutrient
vessels to the metaphyses where
they lodge and proliferate
Metaphyseal inflammation →
↑ intraosseous pressure
Bone necrosis &bone resorption.
Physeal plate acts as barrier to
epiphyseal extension of infection
because it is avascular.
Sometimes infection can extend
into the adjacent joint
Bone destruction & New bone formation
Organisms once localized in bone→
Bacteria proliferate and induce
inflammatory reaction and cause cell
Bone undergoes necrosis within first
48 hours →
Bacteria and inflammation spread
within the shaft of the bone and may
percolate throughout the haversian
systems and reach the periosteum→
Segmental bone necrosis
sequestrum (dead piece of bone) →
Rupture of periosteum leads to an
abscess in the surrounding soft tissue
and the formation of draining sinus.
Child or infants with a history of
mild trauma followed in 1-3 days
by rapid onset of fever
Child refuses to use the affected
limb (Guarding ).
High temperatures, rapid pulse
Inability to support weight and
asymmetric movement of
extremities are often early signs
in newborns and young infants.
High fever, Night sweats
Fatigue, Anorexia, Weight loss
Restriction of movement
Local edema, Erythema, &
Sharp local tenderness to palpation
and particularly to percussion over
the site of the lesion
Such signs as hyperaemia of the
skin and fluctuation in the region
of the lesion are very late signs and
are evidence of neglected
Painful focal swelling (+hotness & redness).
Localized Focal point (finger tip ) tenderness over
the affected bone (sever tenderness).
Later, edema,warmth, and redness.
Draining sinus and bone deformity are both rare
in acute disease. When present, these symptoms
suggest subacute or chronic infection.
Adjoining joint movement is restricted due to
joint involvement or associated soft tissue
Blood sample: culture & sensitivity.
Blood cultures are positive in up to
50% of children with acute OM.
High C-reactive protein ..
Aspiration is the
“key” to the diagnosis
Don’t wait for
Aspiration of subperiosteal abcess.
Plain X-ray: Normal in first 3 weeks.
Later, rarified bone & periosteal reaction.
Plain X-ray usually only show soft tissue swelling
and loss of normally visible tissue planes
Plain X-ray can be useful in detecting bone
tumors, fractures, and healing fractures.
Osteopenia, lytic lesions, and periosteal changes are
late radiographic signs, but their absence does not
exclude a diagnosis of acute osteomyelitis.
A lucent moth eaten appearance
Periosteal new bone formation
first 3 weeks.
Soft tissue swelling can be seen by 1-
3 days after infection.
Destructive bone changes don't
occur on plain film until 10-14 days
after infection starts.
Initially see a lucent moth eaten
appearance to bone.
There is extension of infection
through the metaphyseal cortex
leading to periosteal new bone
formation which if untreated may
completely encircle the bone
becoming an involucrum which can
envelope the non viable infected
bone which is called a sequestrum.
Enhanced uptake of the radioisotope,
demonstrates ↑osteoblastic activity of the
infected bone and distinguishes
osteomyelitis from deep cellulitis.
It has a false-negative rate (20%),
particularly in the first few days of illness.
Fractures, bone tumors, and surgery also
cause enhanced technetium uptake
Three-phase technetium radionuclide bone scanning
Bone scan :increase
uptake in area of OM
A bone scan is usually
positive 24 hours after
demonstrates a well
defined focus of tracer
activity 1 - 2 hours
post injection that is
radiotracer in same
area on dynamic
MRI can be extremely helpful in unclear situations
MRI: to differinate between pus and blood.
This test is increasingly used to define bone
involvement in patients with a negative bone scan.
Changes in bone marrow caused by inflammation
result in an area of low signal intensity within
bright fatty marrow.
These abnormalities need to be correlated with the
clinical picture before a diagnosis is made, as they
are not specific for osteomyelitis.
• Early detection
• Superior to plan X
ray & CT Scan &
scan in slected
• Sensitivity 90 –
An ultrasound examination can detect
fluid collections (e.g., an abscess) and
surface abnormalities of bone (e.g.,
CT scan can reveal small areas of
osteolysis in cortical bone.
6. Ewing’s sarcoma.
7. Neuroblastoma .
10. In newborns and infants in whom
osteomyelitis may present as a
pseudoparalysis, also consider nervous
system disease (eg, polio), cerebral
hemorrhage, trauma, scurvy, and child
Metastatic infection in
other bones, serous
cavities,brain and lung
carcinoma in a sinus
tract (A rare, long-
term complication ).
The inflammatory exudate
may develop considerable
pressure and penetrate the
cortex causing sinus tracts
through the cortical bone into
the soft tissues and through
carcinoma in a sinus
tract (A rare, long-term
1. Bed rest.
2. Fluids for dehydration
3. Analgesics, antipyretics.
4. Splint for the limb for comfort.
5. Antibiotics :
Adequate dose regimen.
Bactericidal ; Antistaph.
A sufficiently prolonged antibiotic course are
essential [6 weeks in adults and at least 4 weeks
1. Drainage of
2. Bone drilling: To relieve
pressure and evacuate
pus; if sever pain and
local tenderness persists
An acute osteomyelitis becomes
chronic due to :
Improper drainage of pus in the
Undrained cavity in the bone
Formation of sequestrum.
Presence of foreign bodies .
Sequestrum (dead bone).
Histological picture is
Organisms: are usually mixed
infection. mostly staph. Aureus
E. Coli . Strep Pyogen, Proteus.
Chronic osteomyelitis is
characterized by a
protracted course with
The fistulae may close
during a remission.
In exacerbation, body
tenderness and toxicosis
Pus is again discharged
from the fistulae, sometimes
The treatment of chronic
osteomyelitis in children is somewhat
easier in that the child's periosteum
is capable of bone regeneration.
The basic principle is the same, of
eradicating the avascular bone, and
providing a means for the limb to
regenerate a replacement.
It is a special form of chronic
There is a localized abscess
within the bone near the
Arises insidiously without
history of acute attack.
X-ray: circular or oval cavity
surrounded with a zone of
Treatment: De-roofing of the
cavity & evacuation of pus.
Non-suppurative type of OM
affecting the shafts of long bones.
Diffuse thickening of bone with
encroachment of the medullary canal.
X-ray: increased bone density and
cortical thickening .
Treatment: Gutter to release tension
inside the bone.
temperature, Toxemia, inability to walk.
Deformity, sever pain & tenderness.
Limitation of motion and muscle
Aspiration: pus (pus cells and culture
An infant with septic arthritis
of the left hip.
The child holds his hip rigidly
in the classic position of
flexion, abduction, and
external rotation, a position
that maximizes capsular
The patient is relatively
comfortable as long as the hip
joint remains immobile in this
The joint is further
Plain radiography - Anteroposterior and lateral views
Findings are often normal.
Radiography may be helpful when considering hip
involvement in young children.
Look for soft tissue swelling around the joint,
widening of the joint space, and displacement of tissue
In later stages of progression, look for bony erosions
and joint space narrowing.
Ultrasonography is very sensitive in:
detecting joint effusions generated by septic arthritis.
defining the extent of septic arthritis
Needle guided aspiration.
Differentiating septic arthritis from other conditions (eg,
soft tissue abscesses, tenosynovitis) in which treatment
May be the initial best diagnostic and
therapeutic procedure in the vast majority of
May allow thorough decompression of joint
Can be repeated serially to achieve relief of
symptoms, decrease joint effusion, and clear
bacteria and synovial WBCs.
Poor choice in joints with loculations