Osteomyelitis is defined as bone inflammation caused by a circulating infection. It is characterized by progressive bone destruction. Common symptoms include severe pain, fever, and unwillingness to use the affected limb. Investigation may include blood tests, bone biopsy for culture and sensitivity, and imaging like x-rays, MRI, or bone scan. Treatment depends on factors like patient health, injury severity, and location; and may involve antibiotics, surgery, or both to clear the infection. Complications can include persistent or spreading infection, amputation, sepsis, or malignant transformation of chronic draining sinuses.

1. Definition
Osteomyelitis is defined
as the inflammation of
the bone caused by a
circulating infecting
organism
Characterized by
progressive
inflammatory
destruction of a bone

2. The root words of ‘osteomyelitis’ orginates from the ancient Greek words ‘osteon’ (bone) and
‘meulinos’ (marrow) combined with ‘itis’ (inflammation) giving it its name
Although it is known that bone is normally resistant to bacterial colonization, there are ways where it
can get infected
The infecting organism may reach bone through blood or through events such as trauma, surgery,
the presence of foreign bodies, or the placement of prostheses that disrupt bony integrity and
predispose to the onset of bone infection
The infective process may remain localized within the bone.
Or it may spread through the bone to involve the marrow, cortex, periosteum and the soft tissue
surrounding the bone
When a bone infection persists for months, the resulting infection is referred to as chronic
osteomyelitis and may be polymicrobial.

3. ◦ The bony skeleton is divided into two parts:
1. The axial skeleton
2. The appendicular skeleton
◦ The axial skeleton is the central core unit, consisting
of the skull, vertebrae, ribs, and sternum (74 bones)
◦ The appendicular skeleton comprises the bones of
the extremities (126 bones)
◦ The common sites of occurrence
spine and ribs in dialysis patients
medial or lateral clavicle in IV drug abusers
foot and decubitus ulcers in diabetics
ANATOMY

4. Structure of the
bone 
There are two types of bone tissue:
• compact bone / cortical bone
• spongy bone / cancellous bone
There are three types of cells that
contribute to bone homeostasis.
• Osteoblasts are bone-forming cell,
• Osteoclasts resorb or break down bone
• Osteocytes are mature bone cells.
An equilibrium between osteoblasts
and osteoclasts maintains bone tissue.

5. Compact bone
Compact bone consists of closely packed osteons or haversian systems.
The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae)
of matrix.
Between the rings of matrix, the bone cells (osteocytes) are located in spaces called lacunae.
Small channels (canaliculi) radiate from the lacunae to the osteonic (haversian) canal to provide passageways through the hard matrix.
In compact bone, the haversian systems are packed tightly together to form what appears to be a solid mass.
The osteonic canals contain blood vessels that are parallel to the long axis of the bone.
These blood vessels interconnect, by way of perforating canals, with vessels on the surface of the bone.

6. Spongy bone
Spongy (cancellous) bone is lighter and less dense
than compact bone.
Spongy bone consists of plates (trabeculae) and bars
of bone adjacent to small, irregular cavities that
contain red bone marrow.
The canaliculi connect to the adjacent cavities,
instead of a central haversian canal, to receive their
blood supply.
The trabeculae of spongy bone follow the lines
of stress and can realign if the direction of stress
changes, making it more flexible compared to
compact bone

7. PREDISPOSING FACTORS
Recent trauma or
surgery
Immunocompromised
patients
Illicit IV drug use
Areas with poor
vascular supply
Systemic conditions
such as diabetes and
sickle cell
Peripheral neuropathy

8. Classification
Osteomyelitis can be classified as:
Acute osteomyelitis ; <2 weeks
Subacute osteomyelitis ; 2-3 weeks
Chronic osteomyelitis ; >3weeks to several months
Primary
- Hematogenous
Secondary
- Post trauma, surgery, or sepsis of any etiology

9. Common infecting organisms based on age
•Newborns (younger than 4 mo)
•S. aureus,
•Enterobacter species,
•group A and B Streptococcus species
•Children (aged 4 mo to 4 y)
•S. aureus,
•group A Streptococcus species,
•Kingella kingae
•Enterobacter species
•Children, adolescents (aged 4 y to adult)
•S. aureus (80%),
•group A Streptococcus species,
•H. influenzae
•Enterobacter species
•Adult
•S. aureus
•occasionally Enterobacter
•Streptococcus species

10. OTHER UNCOMMON ORGANISM BASED ON
ETIOLOGY
•Salmonella
•Sickle cell anemia patients
•However S. aureus is still most common
•Pseudomonas
•IV drug use with AC or SC joint infection or puncture wound
through rubber soled shoes
•Bartonella •HIV/AIDS patient following cat scratch or bite
•Fungal osteomyelitis
•Immunosuppressed,
•long-term IV medications, or parenteral nutrition
•Tuberculosis •Manifestations include Potts disease

11. Osteomyelitis
classification
◦ Can be classified via three main
classifications
◦ Cierny Mader
◦ Weiland
◦ Kelly

12. Cierny Mader Classification
This classification considers host immunocompetence in addition to anatomic
involvement of osteomyelitis.
The anatomical part specifies four stages:
• Stage 1 disease involves medullary bone and is usually caused by a single organism
• Stage 2 disease involves the surfaces of bones and may occur with deep soft-tissue wounds or ulcers
• Stage 3 disease is an advanced local infection of bone and soft tissue that often results from a
polymicrobially infected intramedullary rod or open fracture; stage 3 osteomyelitis often responds well
to limited surgical intervention that preserves bony stability
• Stage 4 osteomyelitis represents extensive disease involving multiple bony and soft tissue layers; stage
4 disease is complex and requires a combination of medical and surgical therapies, and postoperative
stabilization may be needed if the infected bone is an essential weightbearing bone
The second part of the Cierny-Mader classification system describes the
physiologic status of the host, as follows:
• Class A hosts have normal physiologic, metabolic, and immune functions
• Class B hosts are systemically (Bs) or locally (Bl) immunocompromised; individuals with local and
systemic immune deficiencies are labeled as ‘‘Bls’’
• In Class C hosts, treatment poses a greater risk of harm than osteomyelitis itself; the state of the host
is the strongest predictor of osteomyelitis treatment failure, and thus the physiologic class of the
infected individual is often more important than the anatomic stage
Stage 1 and 2 disease usually do not require surgical treatment,
whereas stage 3 and 4 respond well to surgical treatment

13. Weiland
Classification
Weiland classification specifies the following three types:
• Type I osteomyelitis was defined as open exposed bone without evidence
of osseous infection but with evidence of soft-tissue infection
• Type II osteomyelitis showed circumferential, cortical, and endosteal
infection, demonstrated on radiographs as a diffuse inflammatory
response, increased bone density, and spindle-shaped sclerotic thickening
of the cortex; other radiographic findings included areas of bony
resorption and often a sequestrum with a surrounding involucrum
• Type III osteomyelitis revealed cortical and endosteal infection associated
with a segmental bone defect
The Weiland classification categorizes chronic osteomyelitis
as a wound with exposed bone, positive bone culture results,
and drainage for more than 6 months.
This system also considers soft tissue and location of
affected bone. It does not recognize chronic infection if
wound drainage lasts less than 6 months.

14. Kelly Classification
The Kelly classification considers the
following types of osteomyelitis in adults:
Hematogenous
osteomyelitis
Osteomyelitis
in a fracture
with union
Osteomyelitis
in a fracture
with nonunion
Postoperative
osteomyelitis
without
fracture
This system emphasizes the etiology of
the infection along with its relation to
fracture healing

15. Mechanism of
spread
1. Hematogenous
◦ most common etiology in children
◦ vertebrae are the most common hematogenous
site in adults
◦ S. aureus is the most common organism
2. Contigeous-spread
◦ associated with previous surgery, trauma, wounds,
or poor vascularity
◦ can be bacterial (most common), mycobacterial,
or fungal in nature
3. Direct-inoculation

16. HEMATOGENOUS SPREAD
Hematogenous
osteomyelitis in adults
most commonly
involves the vertebrae
Infection may also
occur commonly in the
metaphysis of the long
bones, pelvis, and
clavicle
Commonly being
transported by blood
It may be due to
bacterial or viral
systemic illness
Vertebral osteomyelitis
usually involves two
adjacent vertebrae with
the corresponding
intervertebral disk.
The lumbar spine is
most commonly
affected, followed by
the thoracic and
cervical regions.

17. Primary hematogenous
osteomyelitis is more common
in infants and children
Usually occurs in the long-bone
metaphysis
But it may spread to the
medullary canal or into the joint
Secondary hematogenous
osteomyelitis is also common
and can develop from any
primary focus of infection or
from reactivation of a previous
infection in the presence of
immunocompromised status.
In adults, the location is also
usually metaphyseal

18. The metaphysis is the region of a long bone between the
epiphysis and the diaphysis.
This part contains the growth plate and because of its vascular
characteristics, is the preferred region of hematogenous
osteomyelitis
Presence of U-shaped small end arterioles are present mainly at
the metaphysis region
• Easy for infected embolus to trap
Lack of phagocytosis activity
Highly vascularized region
Why METAPHYSIS is common place?

19. WHAT HAPPENS ONCE BACTERIA ENTERS
THE BONE?
In the long bones, the blood supply
penetrates the bone at the
midshaft but then splits into two
segments traveling to each
metaphyseal endplate.
These vessels are terminal, and
bacteria enter through the nutrient
artery and lodge at the valveless
capillary loops in the junction between
the metaphysis and the epiphysis.
The blood flow through capillary loops
and sinusoidal veins at the epiphyseal-
metaphyseal junction is very slow,
allowing the bacteria to establish and
proliferate.
This region does not permit good
penetration of white blood cells and
other immune mediators, thus serving
to protect the bacteria
As the bacteria continue to multiply,
the scarce functioning phagocytes
release enzymes that lyse the bone,
thereby creating an inflammatory
response.
This results in formation of pus (a
protein-rich exudate containing dead
phagocytes, tissue debris, and
microorganisms), increasing the
intramedullary pressure in the area and
thus further limiting the already
compromised blood supply.
The stasis and cytokine activity
promote clot formation in the blood
vessels, leading to bone ischemia and
then necrosis.
Infection then spreads into the vortex
through the Haversian system and
Volkmann canals and finally into the
subperiosteal space.
The infection and the formation of
pus in this region strip the periosteum
from the shaft and stimulate an
osteoblastic response.
As a result, new bone is formed in
response to the periosteal stripping.
Part of the necrotic bone may separate;
this is referred to as the sequestra
In a severe infection, the entire shaft is
encased in a sheath of new bone,
which is referred to as the involucrum
Once this occurs, a major part of the
shaft has been deprived of its blood
supply
The involucrum can have openings
called cloacae, which allow pus to
escape from the bone, leading to
fulminant disease

20. ◦ The hall mark of infection is
◦ Aggressive and rapidly changing features (lysis, cortical breach and fracture)
◦ Mixed with slower reactions (sclerosis, periosteal reaction and heterotrophic
bone)
◦ If an abscess cavity forms in bone and breaks through the soft tissue and
skin and a discharging sinus is noted, this is a pathognomonic sign of
infection
◦ The hole in the bone develops a sclerotic margin and is called a cloaca

22. History taking
History
• Duration of symptoms
• Any recent travel
• Recent treatments or
surgical procedures
• Immunocompromised
Symptoms
• Severe and constant pain
• fever
• Unwillingness of use
limb
• Anorexia/malaise

23. Examination
• Look for signs of fever, tachycardia, and hypotension suggest sepsis
Vital signs
CALOR (warm) / RUBOR (redness) / DOLOR (pain) / TUMOUR (swelling)
• more common in chronic osteomyelitis
Any draining sinus tract
Poor healing ulcer
Dark skin (malnourished)
Contractures
Muscle wasting

24. Investigations
WBC count
• usually will be markedly high
Blood cultures
Aspiration over the point of maximal tenderness
• Must be sent for c/s for appropriate antibiotics sensitivity
CRP and ESR
• elevated levels
Definitive diagnosis can be obtained through biopsy samples
; tissue fragments from site of infection
•Obtaining sinus tract cultures are not reliable for guiding
antibiotic therapy
•Gold-standard for guiding antibiotic therapy will be bone
culture

25. Bone biopsy
Bone biopsy leads to a
definitive diagnosis by
isolation of pathogens
directly from the bone lesion.
Should be performed through
uninfected tissue and either
before the initiation of
antibiotics or more than 48
hours after discontinuance.
Open or percutaneous needle
bone biopsy with
histopathologic examination
and culture is the routine for
the diagnosis of
osteomyelitis.
This procedure may not be
necessary if blood cultures
are positive with consistent
radiologic findings.
When clinical suspicion is
high but blood cultures and
needle biopsy have yielded
negative results, a repeat
needle biopsy or an open
biopsy should be performed.
A bone sample can be
collected at the time of
debridement for
histopathologic diagnosis in
patients with compromised
vasculature.
To obtain accurate cultures,
bone biopsy must be
performed through
uninvolved tissue.
Cultures of the sinus tract
may be useful if S
aureus and Salmonella species
are isolated

26. Xray findings
Osteomyelitis is primarily a clinical diagnosis
Xrays are usually negative during the early phase
Plain films show lytic changes after at least 50-75% of the bone matrix is destroyed.
Therefore, negative radiographic studies do not exclude the diagnosis of acute osteomyelitis
• Soft tissue swelling within 24-48 hours of infection
Earliest radiological signs:
• Lytic lesion
• Periosteal thickening
• Endosteal scalloping
• Osteopenia
• Loss of trabecular architecture
• New bone apposition
Other typical early bone changes
These changes may not be evident until 5-7 days in children and 10-14 days in adults

27. Magnetic
resonance
imaging
◦ Magnetic resonance imaging
(MRI) is a very useful
modality in detecting
osteomyelitis and gauging the
success of therapy because of
its high sensitivity and
excellent spatial resolution.
◦ The extent and location of
osteomyelitis is demonstrated
along with pathologic changes
of bone marrow and soft
tissue
Chronic Osteomyelitis,
T1- and T2-weighted sagittal MRIs show bone marrow edema in
L1 and obliteration of the disk space between L1 and L2.

28. Radioisotope bone scan
Within 48 hours of bone infection
Technitium- 99 is the choice for
acute hematogenous osteomyelitis
Accuracy 92%

29. Complication
Persistence or extension of infection
Amputation
Sepsis
• most commonly squamous cell
carcinoma (Marjolin's ulcer)
• Risk factors
• chronic draining sinus
• Treatment ; wide surgical resection
Malignant transformation

30. Treatment
Choice of treatment approach should be based on:
• Patient factors
• immunocompetence of patient
• nutritional status
• Injury factors
• the severity of the injury as demonstrated by segmental bone
loss
• Infection location
• metaphyseal infections heal better than mid-diaphyseal
infections
Other factors to consider as it affects prognosis
and treatment include:
• residual foreign materials and/or ischemic and necrotic tissues
• inappropriate antibiotic coverage
• lack of patient cooperation or desire

31. Non operative approach
Suppressive
antibiotics
• Indications - when
operative
intervention is not
feasible
Hyperbaric oxygen
therapy
• Indications - can be
used as adjunct in
refractory
osteomyelitis

32. Antibiotic
treatment
Antibiotic treatment should be based on the identification of pathogens from bone
cultures at the time of bone biopsy or debridement
Bone cultures are obtained first, and suspected pathogens are then covered by
initiation of a parenteral antimicrobial treatment.
However, treatment may be modified once the organism is identified.
Parenteral and oral antibiotics may be used alone or in combination, depending on
microorganism sensitivity results, patient compliance, and infectious disease
consultation
Prophylactic treatment with the bead chain technique has been suggested in open
fractures to reduce the risk of infection.
Systemic antibiotics supplemented with antibiotic beads are preferred
Traditionally antibiotic treatment of osteomyelitis consists of a 4- to 6-week course
However depending on the response, duration can be shortened

33. Hyperbaric oxygen therapy
Refractory osteomyelitis is defined as acute or chronic osteomyelitis that is not cured after appropriate
interventions
refractory osteomyelitis is commonly seen in patients whose systems are compromised
his condition often results in nonhealing wounds, sinus tracts, and, in the worst case, more aggressive infections
that require amputation.
hyperbaric oxygen therapy (HBOT) is capable of elevating oxygen tension in infected bone to normal or above
normal levels
HBOT helps by promoting osteoclast function as the resorption of necrotic bone by osteoclasts is oxygen-
dependent
HBOT facilitates the penetration or function of antibiotic drugs

34. Operative approach
Operative treatment consists of
the following :
• Adequate drainage
• Extensive debridement of
necrotic tissue
• Management of dead space
• Adequate soft-tissue coverage
• Restoration of blood supply
Indications to consider surgical
approach
• acute osteomyelitis that fails to
improve on IV antibiotics
• subacute osteomyelitis
• abscess formation
• chronic osteomyelitis
• draining sinus

35. Surgical approach
The two major aims of surgical treatment are resection of necrotic bone and thorough debridement of
intraosseous and soft-tissue fistula
When a fracture and stable hardware are involved, surgery is used to treat a residual infection after suppressing
the infection until the fracture heals.
Techniques involve hardware removal followed by treatment of an infected non union, often with an external
fixator.
External fixators, plates, screws, and rods may be used to restore skeletal stability at the infection site.
Since hardware tends to become secondarily infected, external fixation is preferred to internal fixation

36. Extensive wound debridement
◦ Remission or cure is most likely with extensive debridement, obliteration of dead space, removal of any hardware,
and appropriate antibiotic therapy.
◦ Debridement of all nonviable or infected tissue is critical because retained necrotic or infected debris can result in
osteomyelitis recurrence.
◦ Bone debridement is performed until punctuate bleeding is noted. *paprika sign*
◦ The remaining tissue is still considered contaminated even after adequate debridement of necrotic tissue.
◦ Studies have shown that marginal resection may be sufficient in normal hosts. However, in compromised hosts,
extensive resection seems to be much more important.

38. Dead space
“Dead space” refers to the soft
tissue and bony defect left
behind after debridement.
Appropriate management of
this space is necessary to reduce
the risk of persistent infection
from poor vascularization of
the area and to maintain the
integrity of the skeletal part.
Dead space must be filled with
durable vascularized tissue,
sometimes from the fibula or
ilium.
Antibiotic-impregnated beads
may be used for temporary
sterilization of dead space
Within 2-4 weeks, the beads may
be replaced with cancellous
bone graft.

39. Dead space management
Goal is to replace dead bone and scar tissue with vascularized tissue
• vascularized bone grafts
• local tissue flaps or free flaps
• antibiotic-impregnated acrylic beads (PMMA)
• vacuum-assisted closure
Options include
• improves wound healing and dead space closure in multiple ways
• remove interstitial fluids
• eliminate superficial purulence or slime
• allow arterioles to dilate, which allows granulation tissue to proliferate
• decrease in capillary afterload to promote inflow of blood
• mechanical force on wound edges draws them in
Vacuum assisted closure

40. Ilizarov technique
The Ilizarov technique is usually suggested by surgeons as its with little associated pain.
The Ilizarov method, promotes bone growth through distraction osteogenesis using a specialized device and systematic approach.
It involves the use of a tissue-sparing cortical osteotomy-osteoclasis technique that preserves the osteogenic elements in the limb. to create a preliminary callus that can
be lengthened.
A high-frequency, small-step distraction rhythm permits regeneration of good-quality bone and leads to fewer soft-tissue complications
The Ilizarov method is based on the concept of "tension stress," in which gradual distraction stimulates bone production and neogenesis
This technique has facilitated limb lengthening, decreased the incidence of many complications, and therefore decreasing the level of surgical intervention necessary.
The advantage of using this procedure is that it minimizes the prevalence of nonunion and thus further bone grafting by producing good-quality bone formation.
However, Ilizarov techniques are often not tolerated well by patients, and other options, including amputation, may be preferred.
A few complications that have been reported include pin-tract infections and cellulitis, flexion contractures above and below the frame, limb edema, and bone-fragment
rotation with malunion

41. Amputation
At the level that will
eradicate infected
tissue to healing tissue
with capacity to heal
Prevent spread of
infection further

42. THANK YOU