Objectives
At the end of this lecture we should be able to:
Define acute OM.
Describe the natural history of the evolution of
acute OM.
Describe the clinical and radiographic features of
acute OM.
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
marrow.
Age: 50% of cases occur in
preschool-aged children.
Disease of childhood ; but can
occur in adults.

Classification of osteomyelitis
A. Duration-
❖ acute (less than 2 weeks)
❖ subacute ( 2-6 weeks(
❖ chronic (>6 weeks)
B. Mechanism
❖ Exogenous
❖ hematogenous.

The organisms
bone by:
Blood
can reach the
stream
(haematogenous).
From without (an infected
open fracture).
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
contamination.
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
for malignancy.

Gram +ve
Staphylococcus aureus
[70-90 %]
Community-associated
methicillin-resistant
S. aureus has also
become an increasing
problem .
Streptococci pyogen
Pneumococci.
Gram –ve
Haemophilus influenzae(50%
< 4 y)
E .coli
Pseudomonas auroginosa,
Proteus mirabilis.
Organism:
Salmonella is a common
pathogen in patients with
sickle-cell anemia.
Immunocompromised
children are prone to
infection with a variety of
fungi and bacteria.

The organism usually
reaches the blood
stream from a septic
focus
(tonsillitis,
furuncles and
skin
boils,
chest infection).
tonsillitis
boil
furuncles

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.

Diaphysis
metaphysise
E.P
Epiphysis
E.P
Epiphysis
metaphysise

Metaphysis of
long bones (tibia,
femur; humerus)
The commonest
sites are the lower
end of femur and
the upper end of
the tibia.
Site

Vascular arrangement :
Blood flow slows down in
large sinusoidal veins.
Vulnerable to minor trauma,
as (site of attachment of
ligaments).
Lack of active phagocytosis
in metaphysis ; as compared
to diaphysis.
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 →
Exudation
↑ intraosseous pressure
Vascular stasis
Thrombosis
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
E.P

Acute inflammatory
reaction :↑ intraosseous
pressure →
Intense pain
Obstruction of blood flow
Interavascular thrombosis.
Local changes

Suppuration:
pus forms
rapidly which
spread
→
subperiosteal
abscess.

.Acute O.M with an abscess in the medulla

Bone destruction & New bone formation
Sequestration
(necrosis, bone
death).
New bone
formation
(involucrum).

Organisms once localized in bone→
Bacteria proliferate and induce
inflammatory reaction and cause cell
death. →
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→
Subperiosteal abscess→
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.
Subperiosteal abscess.
Involucrum

The diagnosis of
osteomyelitis is
based primarily on
the clinical findings,
with data from the
initial history,
physical
examination and
laboratory tests.

Child or infants with a history of
mild trauma followed in 1-3 days
by rapid onset of fever
Bone pain
General malaise
Child refuses to use the affected
limb (Guarding ).
High temperatures, rapid pulse
and toxemia.
Inability to support weight and
asymmetric movement of
extremities are often early signs
in newborns and young infants.

Sudden onset
High fever, Night sweats
Fatigue, Anorexia, Weight loss
Restriction of movement
Local edema, Erythema, &
Tenderrness
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
osteomyelitis

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
inflammation.
Physical Examination

Blood sample: culture & sensitivity.
Blood cultures are positive in up to
50% of children with acute OM.
CBC:PMN leucocytosis.
High ESR.
High C-reactive protein ..

Aspiration is the
“key” to the diagnosis
Don’t wait for
imaging
Subperiosteal aspiration
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
Radiology:
❑Normal in
first 3 weeks.
❑Soft tissue
swelling
❑Periosteal
elevation
❑Lytic change
❑Sclerotic
change

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.
plain film

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
infection and
demonstrates a well
defined focus of tracer
activity 1 - 2 hours
post injection that is
correlated with
radiotracer in same
area on dynamic
scans.

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.
MRI

:MRI
• Early detection
• Superior to plan X
ray & CT Scan &
radionuclide bone
scan in slected
anatomic location.
• Sensitivity 90 –
100%

An ultrasound examination can detect
fluid collections (e.g., an abscess) and
surface abnormalities of bone (e.g.,
periostitis).
CT scan can reveal small areas of
osteolysis in cortical bone.

1.Rheumatic arthritis
2.Septic arthritis.
3.Cellulitis.
4.Subcutaneous abscess
5.Sickle-cell crisis

6. Ewing’s sarcoma.
7. Neuroblastoma .
8. Osteosarcoma.
9. Fractures
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
abuse.

Septic arthritis.
Chronic OM.
Metastatic infection in
other bones, serous
cavities,brain and lung
Pyameia.
Pathological fracture.
Squamous cell
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
the skin
Squamous cell
carcinoma in a sinus
tract (A rare, long-term
complication ).
Sinus

1. Bed rest.
2. Fluids for dehydration
3. Analgesics, antipyretics.
4. Splint for the limb for comfort.
5. Antibiotics :
Broad spectrum.
Adequate dose regimen.
Bactericidal ; Antistaph.
Injection
A sufficiently prolonged antibiotic course are
essential [6 weeks in adults and at least 4 weeks
in children].

1. Drainage of
subperiosteal abscess.
2. Bone drilling: To relieve
increased intraosseous
pressure and evacuate
pus; if sever pain and
local tenderness persists
hours of
antibiotic
after 24
effective
treatment.

An acute osteomyelitis becomes
chronic due to :
Improper drainage of pus in the
acute stage.
Undrained cavity in the bone
Formation of sequestrum.
Presence of foreign bodies .

❖May follow acute OM
❖May start De Novo:
❑following operation
❑following
open fractures

Pathology:
one of
Bone cavity.
Sequestrum (dead bone).
Sinuses.
Cavities
Cloacae
Involucrum
Histological picture is
chronic inflammation
Organisms: are usually mixed
infection. mostly staph. Aureus
E. Coli . Strep Pyogen, Proteus.

Sequestrum

Chronic osteomyelitis is
characterized by a
protracted course with
remissions and
exacerbations.
The fistulae may close
during a remission.
In exacerbation, body
temperature increases,
tenderness and toxicosis
intensify.
Pus is again discharged
from the fistulae, sometimes
in abundance

Sinogram

Right leg chronic osteomyelitis in
a 70-year-old diabetic man. He
has had this wound for 15 years.
Skin biopsy was negative for
malignancy.
Cortical defect and intramedullary
sequestrum.

Sequestrectomy
& saucerisation
Excision of
sinus tract.
Sequestrectomy & saucerisation

Treatment of
chronic
osteomyelitis in
adults is sometimes
compared to
treating entities
such as giant cell
tumors, in that a
radical resection of
the infected bone is
the first step,
followed by efforts
at reconstruction.

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.

Antibiotic (Gentamycin)
impregnated collagen sheet
(Septocol sheet) to assist in
local control of infection,
Papineau's open bone
grafting technique.

Pathological Fr.
Amyloid disease in long
continued chronic OM with
persistent discharging pus.
Retardation of growth of bone
due to affection of epiphyseal
plate.

It is a special form of chronic
OM.
There is a localized abscess
within the bone near the
metaphysis
Arises insidiously without
history of acute attack.
X-ray: circular or oval cavity
surrounded with a zone of
sclerosis.
Treatment: De-roofing of the
cavity & evacuation of pus.
Brodie’s Abscess

MRI

Non-suppurative type of OM
affecting the shafts of long bones.
No abscesses.
No sinuses.
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.

BoneScan Tec- bone scan in sclerosing OM

Septic arthritis (bacterial,
suppurative, purulent, or
infectious arthritis ) is
inflammation of a synovial
membrane with purulent
effusion into the joint capsule,
usually due to bacterial infection.

1. Haematogenous
❖
❖
❖
2. Acute OM (interarticular
metaphysis)
3. Direct invasion
Pnetrating wound
Intra-articular inj
Arthroscopy

Organisms: Staph. Aureus,
Streptococci
Haemophilus
or
influenza;
E.coli.
Pathology: Infection starts
in the synovial membrane
(synovitis) then articular
cartilage is destroyed.
Subchondral marrow
spaces are filled with pus.

temperature, Toxemia, inability to walk.
Deformity, sever pain & tenderness.
Limitation of motion and muscle
spasm.
Leucocytosis .
ESR.
Aspiration: pus (pus cells and culture
& sensitivity).

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
volume.
The patient is relatively
comfortable as long as the hip
joint remains immobile in this
position.
The joint is further
subluxated

Bacteria
Enzymes
Destroy cartilage
Irreversible joint damage
White cells
Enzymes
Septic Arthritis

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
planes.
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 differ.
Imaging Studies

3 weeks after
presentation, Lt. hip is
dislocated, and new
periosteal bone formation
is noted (an associated
osteomyelitis of Lt.
femur).

May be the initial best diagnostic and
therapeutic procedure in the vast majority of
cases
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
Diagnostic Procedures

Rest
Fluids.
Splint
Systemic
antibiotics.
Arthrotomy
(drainage).

Bone destruction.
Chronic septic
arthritis.
Pathological
dislocation
Growth disturbance
due to destruction
of the epiphysis.

❑Complete recovery
❑Partial loss of the
articular cartilage
❑Fibrous or bony
ankylosis

1. Acute
osteomyelitis
2. Trauma
3. Irritable joint
4. Hemophilia
5. Rheumatic fever
6. Gout
7. Gaucher disease