A seminar and case report on chronic osteomyelitis focussing on radiological and histological features, differentials plus recent advances.

1. ORTHO PATHO MEET
CHAIRPERSON: DR. SARANG SHETE
PRESENTER: DR. ANMOL R. MITTAL

2. PATIENT DETAILS
NAME : XYZ
AGE: 28 YRS
SEX: MALE
OCCUPATION: LABOURER
ADDRESS- BELAGAVI

3. CHIEF COMPLAINTS
Pus discharge from upper right leg.
Pain in the right upper leg.

4. HISTORY OF PRESENTING ILLNESS
 History of road traffic accident 2 years back following which
he was diagnosed with fracture of proximal aspect of both bone
of the right leg. He was then operated upon for the same with
proximal tibial plating and the limb was immobilized post-op for
2 months.
 1 month later he noticed pus discharge from the distal aspect
of suture site (~3 cms distal to tibial tubercle) for which he was
started on IV antibiotics for a period of 1 month after which the
discharge reduced.

5. 3 months later he had a recurrence and was again started on IV
Antibiotics. As it did not subside after a course of 1 month, the
implant was removed and antibiotics were continued orally.
Since 3 months post op patient was ambulatory without support.
 The patient again noticed pus discharge 2 weeks back for which
he came to KLE OPD and was admitted in view of further
management. (1 year and 10 months from the date of injury)
No h/o fever, significant weight loss/ loss of appetite/ bone pieces
in discharge/ lump or swelling/ Pain not relieved on taking NSAIDs

6. PAST HISTORY
No history of Diabetes Mellitus/ Hypertension/ chronic
medication or blood transfusion/ TB or TB contact/ Asthma/
Allergy to any medication.
FAMILY HISTORY:NOTHING SIGNIFICANT

7. PERSONAL HISTORY
Diet : vegetarian
Appetite : Adequate
Sleep : undisturbed
Bowel & Bladder : Regular
No h/o of any addiction

8. GENERAL PHYSICAL EXAMINATION
A young male patient , moderately built & nourished, conscious,
co-operative & well oriented to time, place & person.
Vitals:
PR:92/min
BP: 110/70 mm of hg
SPO2: 100%
TEMP: Afebrile.
No pallor /icterus/cyanosis/clubbing/ lymphadenopathy/ oedema

9. LOCAL INSPECTION
Ulcer with unhealthy granulation tissue present over the anterior
aspect (~3cms distal to the tibial tubercle) of upper right leg
approximately 5-6 cms distal to the anterior joint line of the knee.
1 in number and (5x3) cms in size with active persistent pus
discharge suggestive of a sinus opening. No bony pieces visible in the
discharge.
It is present at the distal end of a suture line healed in its proximal
length.
Surrounding skin exhibits loss of hair, edema, hyperpigmentation
and is shiny.

10. PALPATION
All the inspectory findings confirmed on palpation.
Local rise of temperature present.
Tenderness present.
Thickening and irregular underlying bony surface palpable around the
wound.
Wound is fixed to the underlying soft tissues and bone.
No palpable lymph nodes
Knee joint ROM full, painless.
No distal neurovascular deficit

11. BLOOD INVESTIGATIONS
Hb-14.6 g/dl
WBC : 14300/uL,
N-68, L- 10, E -01,
M-21
ESR- 110
RBC-3.97
UREA -21
S.CREATININE-0.61
HIV, HBsAg, HCV: NR
CALCIUM : 9.6
PHOSPHOROUS : 3.2
ALP: 41
SGOT: 18 U/L
SGPT:15 U/L
SODIUM:136 mg/dl
POTASSIUM : 4.15 mg/dl

12. X RAY RIGHT LEG
AP/LATERAL

13. CULTURE/ SENSITIVITY
Positive for Staphylococcus epidermidis sensitive to
• Tobramycin
• Gentamycin
• Linezolid
• Vancomycin.

14. DIFFERENTIAL DIAGNOSIS
• Chronic Osteomyelitis
• Cellulitis
• Osteiod Osteoma
• Osteoblastoma
• Ewing’s Sarcoma

15. CHRONIC OSTEOMYELITIS CELLULITIS
Infection of bone present usually
>6 weeks
 Site- long bones, metaphysis>
diaphysis
 Symptom- pain and slow growing
swelling, with frank pus discharge
and flue like symptoms such as
malaise, weakness , tiredness
 X ray – periosteal thickness, lytic
lesion, osteopenia, sequestrum,
involucrum, sinus tract.
 H/o skin infection, diabetes,
immunocompromised state, ulcer,
venous or lymphatic insufficiency.
 Site – MC lower limbs> Periorbital>
Upper limb
Symptoms and signs: low grade fever,
chills, malaise, severe erythema, local
rise of temperature, tenderness, small
amount of pus discharge, peau d’orange,
advancing edge of lesion diffuse,
lymphadenopathy.
X Ray – shows only soft tissue edema

16. OSTEIOD OSTEOMA OSTEOBLASTOMA
Age- 2nd and 3rd decades
Site- lower extremity, long
bones, diaphyseal/metaphyseal.
Symptom- pain relieved by
Nsaids
Imaging- cortical radiolucent
nidus (≤1.5cm) with marked
cortical thickening.
Age- 2nd and 3rd decades
Sites- spine> lower extremity,
long bones, epiphysis>
metaphyseal
Symptom- pain less intense, not
relived by aspirin
Imaging- lytic radiolucent nidus
(>1.5cm) with less reactive
sclerosis with bone expansion.

17. EWING’S SARCOMA
 Age- 1nd and 2nd decades
 Site- lower extremity, long bones, diaphyseal.
 Symptom- pain and rapidly growing swelling, flu like symptoms
such as malaise, weakness.
 Imaging- cortical thickening with onion peel appearance.

18. MANAGEMENT
Patient underwent debridement and curettage and a window was
made with multiple drill holes.
Cortical bone and surrounding soft tissue was sent for
Histopathological testing and post-operatively the patient was
continued on IV antibiotics as per the previous culture sensitivity
report.
Patient was relieved of symptoms partially.

19. HISTOPATHOLOGY
Gross: Received a Grey- white specimen with an irregular outline,
having bony consistency measuring (1.8 x 0.8 x 0.2) cms
Microscopy: Sections studied shows lacunae surrounded by a
considerable number of polymorphonuclear leukocytes, lymphocytic
infiltration in blood vessels and marrow fibrosis. Granulation tissue
noted.
Impression: Features suggestive of chronic osteomyelitis.

20. FURTHER PLAN OF MANAGEMENT
 In case of a recurrence of exacerbation, antibiotic impregnated
cement beads or saucerization with intramedullary reaming followed
by antibiotic impregnated nailing for a period of 6 weeks will be
done.
Simultaneous repeat histopathological and culture studies from the
site.

21. CHRONIC OSTEOMYELITIS
OSTEOMYELITIS is defined as an inflammation of the bone caused by
an infecting organism.
The term is popularly said to be coined by Nelaton in 1834 but was
first instigated by Reynaud in the 17th century
Etymology: OSTEON (Bone) – MYELO (Marrow) – ITIS (inflammation)
Osteomyelitis is considered to be chronic if it lasts more than 6
weeks although the histopathological picture is considered to be a
more reliable marker than the duration.

22. ETIOLOGY
Hematogenous osteomyelitis is considered to have the following etiology based on
history:
1) Staphylococcus aureus: Pressure ulcer, penetrating wound, open fracture, orthopedic
surgery, vascular insufficiency disorder
2) Staphylococcus epidermidis :Indwelling prosthetic device/ implant
3) Streptococcus viridans: Abscessed tooth, gingival disease
4) Escherichia coli: Urinary tract infection
5) Mycobacterium tuberculosis: Tuberculosis
6) Neisseria gonorrhoeae: Gonorrhea
7) Pseudomonas sp.: Puncture wounds, intravenous drugs
8) Salmonella sp.: Sickle cell disease
9) Fungi, mycobacteria: Immunocompromised host

23. Based on age:
1. 2 to 4 weeks old : Group B Streptococcus, Staph aureus, E. Coli
2. 6 months to 4 years : Hemophilus Influenzae, Staph Aureus
3. 4 years to 16 years: S. aureus, S. pyogens, H.influenzae
4. >16 years: Staph aureus, S epidermidis, Gram -ve Bacilli

24. PATHOGENESIS

25. 1. LOCAL FACTORS + PLANKTONIC / STATIONARY BACTERIA
2. COMPROMISE THE VASCULAR SUPPLY
3. MEDULLARY INFECTION SPREADS AND THROMBOSIS CAUSES BONE NECROSIS
4. LACUNAE BECOME DEVOID OF OSTEOCYTES AND FILLED WITH PUS
5. SUPPURATIVE INFLAMMATION EXTENDS THROUGH THE CORTICAL BONE INTO THE PERIOSTEUM
6. PERIOSTEUM BULGES AND EVENTUALLY GETS STRIPPED DUE TO THE PRESSURE
7. COMPROMISES BLOOD SUPPLY TO THE CORTICAL BONE FURTHER
8. SEQUESTRUM IS FORMED
9. INADEQUATE TREATMENT / HOST FACTORS
10. INFECTION IN MEDULLARY SPACES SPREAD AND FORM GRANULATION TISSUE
11. GRANULATION TISSUE FORMS DENSE SCAR TO WALL OFF INFECTED AREA ACCOMPANIED BY PREMATURE BONE
INVOLUCRUM

27. INVOLUCRUM: immature, subperiosteal, reactive, living new bone formation around dead bone.
SEQUESTRUM: A dead piece of bone separated from the living bone by a layer of unhealthy
granulation tissue lying in a cavity.
TYPES:
1. Pencil like/ Cylindrical / tubular : Infants
2. Ring shaped : External fixator
3. Conical/ Annular : Amputation stump
4. Coralliform: Perthe’s , Pyogenic
5. Coke like: Tuberculosis
6. Feathery: Pyogenic infection, TB of rib
7. Dense ivory: Syphilis
8. Sand like: Tubercular osteomyelitis in metaphysis
9. Black (BOMBAY): amputation stump, exposed necrotic bone, fungal infection, calcaneal, ulnar
and tibial osteomyelitis
10.Green: Pseudomonal infection
11. Buttonhole: Pott' puffy tumour, Tuberculosis of skull bones, After radiation therapy
12.Kissing : Paradiscal TB
13.Match stick: Sickle cell disease

29. CIERNY- MADER CLASSIFICATION
(1985)
STAGE TYPE FEATURES
I MEDULLARY Endosteal disease
II SUPERFICIAL Cortical surface infected because
of coverage defect
III LOCALIZED Conical sequestrum that can be
excised without compromising
stability
IV DIFFUSE I, Il and Ill plus mechanical
instability before or after
debridement.
ANATOMIC TYPE

30. CLASS IMMUNE SYSTEM FEATURES
A HOST
(young children: A1+++)
NORMAL Immunocompetent with good
local vascularity.
B HOST COMPROMISED Local(Bl) or Systemic (Bs) or
both (Bls) factors that
compromise immunity or
healing.
C HOST PROHIBITIVE Minimal disability, prohibitive
morbidity anticipated, poor
prognosis for cure, treatment
worse than disease.
PHYSIOLOGICAL CLASS
Anatomic stage and Physiological class are combined to give 12 clinical stages.
APPLICATION: - To decide whether treatment should be
1) Simple or Complex
2) Curative or Palliative
3) Limb sparing or Ablative

31. CLINICAL FEATURES
DURING THE PERIOD OF INACTIVITY:
1.Usually no symptoms
2.Skin over the focus is dusky, thin, scarred, poorly nourished
3.Break in the skin causes ulceration that heals slowly
4.Muscles are scarred & leads to contractures of the adjacent joints
DURING ACUTE EXACERBATION:
1. Aching pain worsening at night, overlying soft tissue becomes edematous, warm,
red & tender.
2.patient is febrile
3.As infection progresses, sinus may open up & drain extruding small sequestrum at
Intervals
4.Intervals between flare ups may be months or years
5.Flare ups may be due to poor general condition & lowered resistance
6.Recurrent toxaemia will eventually cause debility & sometimes fatal amyloidosis

32. DIAGNOSIS
LABORATORY INVESTIGATIONS
1. Nonspecific
2. Gives no indication of severity of infection
3. Raised ESR & HSCRP
4. Raised WBC ( Raised Lymphocytes) in 35% patients
5. Biopsy with Culture & Sensitivity (Gold Standard)

33. NORMAL BONE
CHRONIC OSTEOMYELITIS
TUBERCULAR OSTEOMYELITIS
ACUTE OSTEOMYELITIS

34. HISTOLOGICAL COMPARISON
ACUTE
Neutrophils (may persist for weeks),
lymphocytes and plasma cells with bone
necrosis and reactive new bone formation
Capillary proliferation and fibrosis
Bone marrow space replaced by
inflammatory tissue
Loss of osteocytes from lacunae
Peripheral resorption
Salmonella infection may produce
tuberculoid granules with variable central
necrosis
CHRONIC
Similar features as acute osteomyelitis
with large amounts of polymorphonuclear
leucocytes, macrophages and plasma cells.
Variable degree of marrow fibrosis and
reactive bone formation, minimal marrow
adipose
Periosteum still contains osteogenic
potential in most cases, which contributes
to formation of a bony shell (involucrum)
covering the sequestra

35. RADIOLOGY
PLAIN RADIOGRAPH:
It takes from 10 to 21 days for an osseous lesion to become visible on conventional
radiography, because a 30—50% reduction of bone density must occur before
radiographic change is apparent
Earliest radiographic changes appears after 10-12 days
In early stages, bone appears moth eaten & osteoporotic due to cortical destruction
with sclerotic areas
Periosteum is elevated by subperiosteal laminations of new bone
Gradually each necrotic dense area becomes surrounded by white ring representing
new bone formation, the INVOLUCRUM

37. OTHER INVESTIGATIONS:
MRI: Shows early inflammatory changes in bone marrow and soft tissue. Useful for
detecting intraosseous and sub-periosteal abscess. Reveals well defined rim of high
signal intensity surrounding the focus of active disease.
T1 weighted images: Osteomyelitis shows low intensity
T2 weighted and STIR images: High marrow intensity
 CT: Provides excellent definition of cortical bone, soft tissue and sequestra.
Technetium 99m bone scan: Confirms diagnosis in 24-48 hours in 90% patients.
Negative scan rules out OM.
MOA: Binds to hydroxyapatite crystals. Shows increased uptake in the areas
of increased blood flow or osteoblastic activity

38. Gallium 67 scan: shows increased uptake in areas where leucocytes or bacteria
accumulate. Normal Ga scan excludes presence of osteomyelitis. Useful as follow up
examination after surgery. Best for vertebral OM.
Indium 111 labelled leukocyte scan: Useful in differentiating chronic osteomyelitis
from diabetic neuropathy. Specificity can further be increased by using it in
conjunction with sulphur colloid scans that delineate normal bone whereas the former
highlights involved regions.
USG: Differentiates acute OM from cellulitis, soft tissue abscess, acute septic arthritis,
bone tumors.
Other include FDG-PET and SPECT scans.

39. SINOGRAM: Most important procedure done pre operatively in chronic OM cases to
delineate sinus tracks.
MOLECULAR STUDIES: Identification procedures based on molecular analysis and RNA
or DNA typing are currently in development to facilitate diagnosis in osteomyelitis. The
most commonly used method is PCR technique.

40. TREATMENT
GOAL: Eradication of the infection by achieving a viable and vascular environment.
SURGICAL INTERVENTION IS THE MAINSTAY OF TREATMENT IN CHRONIC OM.
PRINCIPLE OF SURGERY: Success of treatment depends on adequacy of debridement.
Hence, an oncological approach of wide excision should be taken.

41. SEQUESTRECTOMY & CURETTAGE
1. All sinus tracts are excised completely along with sequestra, purulent material &
scarred and necrotic tissue. If sclerosis bone seals off a cavity within the medullary
canal, it is opened into the canal in both directions to allow blood vessels to grow into
the cavity.
2. When medullary canal is infected intramedullary reaming as a debridement
technique has shown favourable results in the treatment of medullary osteomyelitis.
3. Wound is either packed open or closed loosely over drains.

42. AFTER TREATMENT
 Limb is splinted until the wound is healed & then it is protected to prevent
pathological fracture
 Prolonged antibiotic therapy is given usually for 6 weeks
 Bony & soft tissue defects must be filled to reduce chances of continued infection &
loss of function
METHODS TO ELIMINATE THIS DEAD SPACE
1) Bone grafting with primary or secondary closure
2) Use of PMMA beads
3) Local muscle flaps & skin grafting with or without bone grafting
4) Microvascular transfer of muscle, myo-cutaneous, osseous & osteo-cutaneous flaps
5) Use of bone transport ( Ilizarov's technique)

43. Four basic methods of
immediate biological
management of dead space
using living tissue or
cancellous bone graft.

44. PMMA ANTIBIOTIC BEAD CHAINS:
-The rationale for this treatment is to deliver levels of antibiotics locally in concentrations that
exceed the minimal inhibitory concentrations.
-The antibiotic is leached from the PMMA beads into the postoperative wound hematoma and
secretion, which act as a transport medium
-Aminoglycosides are the most commonly employed antibiotics.
-Most commercially available bone cements have a pre-packaged form available with GENTAMICIN
(500mg/40g) which is later fortified with VANCOMYCIN(2-4g/40g) with or without TOBRAMYCIN
(1.2g)
- In short-term implantation, the beads are removed within 10 days and in long-term implantation,
they may be left for 80 days.

45. ANTIBIOTIC BEAD CHAIN TECHNIQUE:
 Used in open fractures, fractures in which soft tissue coverage is impossible after initial
debridement.
 Irrigation done by thorough pulsatile lavage using 9L saline containing bacitracin.
 Several beads are placed on an 18-20 gauge wire and are placed in the bony defect
 Benzoin is then applied on skin edges and is covered with sterile transparent/ lucent
dressing such as OpSite or ioban dressing. It is changed once in 72 hours.

46. BIODEGRADABLE ANTIBIOTIC DELIVERY SYSTEMS
 Bioabsorbable substrates (calcium sulphate or calcium phosphate) that can be mixed with
antibiotics ( Vancomycin or Tobramycin)
 These beads typically resorb by about 8 weeks after surgery
 Polymethylmethacrylate (PMMA) beads connected together in a chain are the most
widely used drug delivery system.
Advantages
 2nd procedure is not required to
remove the implant.
 Calcium in the substrate can be
used in new bone formation.
 As the beads resorb, they are slowly
replaced by new bone & soft tissue
& this process may decrease the
need for further reconstructive or
coverage procedure.

47. INTRAMEDULLARY ANTIBIOTIC CEMENT NAIL
1. Medullary cavity is reamed followed by irrigation using a Reamer Irrigator Aspirator
device.
2. T-95 Chest tube is cut to the desired length.
3. Antibiotic cement mixture is injected into the tube.
4. Ender nail is inserted into the chest tube.
5. Once polymerization is complete, cut and remove the plastic tube.
6. Post-op NWB cast for 6-8 weeks.

48. CLOSED IRRIGATION & SUCTION
 For resistant focal infections, topical instillation of
solution containing mild detergent ( eg. Alevaire) &
one or more antibiotic seems to be effective -
detergent inhibits the formation of penicillinase
 Closed suction antibiotic ingress and egress high
volume irrigation systems (Lautenbach continuous
irrigation method) can be used over 3 to 21 days.
 the material collected through suction tube is
cultured every day until 3 successive negative cultures
are obtained.
 Castille soap has recently been reported to be useful
in this situation.

49. ILIZAROV'S TECHNIQUE
The Ilizarov technique has been helpful in the treatment of chronic osteomyelitis and infected
nonunions. This technique allows radical resection of the infected bone.
 A corticotomy is performed through normal bone proximal and distal to the area of disease.
The bone is transported until union is achieved.
 Disadvantages of this technique include the time required to achieve a solid union and the
high incidence of associated complications.
ADJUNCTIVE TECHNIQUES:
1. HYPERBARIC OXYGEN CHAMBER
2. BONE MORPHOGENIC PROTEINS
3. PLATELET RICH PLASMA
4. IONOPHORESIS DELIVERY OF SILVER IONS

50. SPECIAL SITES OF OSTEOMYELITIS:
1. CALCANEUM: Cancellous bone with thin periosteum. Minimal cortical destruction
and sequestrum. Treated using GAENSLEN or SPLIT HEEL INCISION in acute cases and
Partial calcanectomy using hurricane incision in chronic OM.
2. DISTAL THIRD FEMUR: Periosteum may become completely separated posteriorly by
a subperiosteal abscess, this part of the bone may lose most of its blood supply, and
sinuses often persist. Incision fron 5 cm proximal to knee joint line to 10 cms further
proximally.
3. ILLIUM: Drainage in acute cases and resection in chronic OM.
4. ISCHIUM AND PUBIS: Drainage, Debridement and soft tissue transfer. Resection of
symphysis.
5. METATARSAL: 1st MT retained as much as possible. Rest can be resected with physis
preserved.
6. FIBULA: Entire fibula except the distal ¼th can be removed.
7. SPINE: Lumbar > thoracic > cervical. Simultaneous involvement of the 2 adjacent
vertebral end plates with intervening discs. Treated using IV antibiotics, rest,
immobilization and/or surgery.

52. COMPLICATIONS
 Growth disturbances
 Pathological fractures
 Muscle contractures and atrophy
 Secondary septicaemia
 Epithelioma
 Malignant changes( Squamous cell ca, Reticulum cell ca, Fibrosarcoma)
 Amyloidosis
 Joint stiffness

53. RECENT ADVANCES
1. Silver has been used as a coating for orthopedic implants to minimize infectious risk. Silver-
hydroxyapatite coated implants may enhance the intrinsic osteoconductive property of the implant. (Wafa
2014, Eto 2016)
2. Use of compounds that promote detachment of stationary colonised bacteria into the planktonic state,
where they are easier to eradicate. In this technique indocyanine green dye is placed into the wound and
activated with near infrared light. The light results in the dye releasing molecules that are toxic to the
MRSA. The mechanism of action is varied and unlike standard antibiotics that development of resistance is
unlikely.
3. Bioactive glass which can elute antibiotics and has the unique ability to provide bone scaffolding for
bone ingrowth. The greatest advantage of bioactive glass-based carrier systems is that they can potentially
provide a system for simultaneously eradicating infection and regenerating bone, thereby eliminating the
need for subsequent bone grafting. (Rahman, Pishbin, Nooeaid, 2014)
4. Coating implants with monocyte chemoattractant protein-1 (MCP-1) and Innate defense regulator
peptide-1018 (IDR-1018) has been found to reduce Staph aureus infection in a rat model of open fracture.
in a murine model (CHOE H. 2015)