Acute Osteomyelitis

Amalina Aminuddin082012100067

• Infection of bone • Mainly affect

children

Introduction

Predisposing factors • Malnutrition and

general debility• Diabetes mellitus• Corticosteroid

administration• Immunosuppressiv

e drugs

• Venous stasis in the limb

• Peripheral vascular disease

• Loss of sensibility• Iatrogenic invasive

measures• Trauma

• Based on duration:• Acute (< 2 weeks )• Subacute (2-3 weeks

)• Chronic ( > 3

weeks )• Based on route of

infection:• Primary(hematogeno

us)• Secondary

• Based on organism• Pyogenic:

Staphylococci, Streptococcus, Pneumococci, Gonococci, H. influenza ,Kingella kingae E. coli, Salmonella sp,

• Non pyogenic: tuberculosis, syphilis,

Classifications

Pathogenesis Children • Hairpin loops stasis• Low oxygen tension • Structure in the

hypertrophic zone of the physis

Infants • anastomoses between

metaphyseal and epiphyseal vessels

Adults • Direct spread

from infection foci

• Local trauma• Hematogenou

s

Pathology • Depend on:• Patient’s age• Site of infection• Virulence of the

organism • Host response.

Acute inflammati

on

Subperiosteal

abscess

Sequestrum

Involcrum

Cloacae

In infants • More common

epiphysial and adjacent joint spread

• Deformed joint, bizzare new bone formation

In adults • Medullary spread in

long bone

Clinical features In child:

• Recent history of infection

• Severe pain, malaise, fever

• Acute tenderness near one of the larger joints

• ‘Pseudoparalysis’.

Infants • History of birth

difficulties, umbilical artery catheterization or a site of infection

• Fails to thrive• Drowsy but irritable. • Metaphyseal

tenderness and resistance to joint movement

Adults • History of some

urological procedure followed by a mild fever and backache.

• Local tenderness• Easily missed

diagnosis in elderly, and in those with immune deficiency,

Diagnostic imaging

•Plain x-ray•Ultrasonography•Radionuclide scanning•Magnetic resonance imaging

• Bone scan reveals increased tracer uptake in the right tibia

• Sagittal T2 reveals marrow edema in the distal tibia which crosses the physis to invade the epiphysis

Investigations • Aspiration analysis• Blood culture• CRP within 12–24 hours • ESR within 24–48 hours

Differential diagnosisCellulitis

• Widespread superficial redness and lymphangitis.

• MRI• Oral or

intravenous antibiotics

Acute suppurative arthritis • Diffuse tenderness • Joint movement abolished

Streptococcal necrotising myositis• Intense pain ,board-like swelling • MRI :muscle swelling, signs of

tissue breakdown.• Intravenous antibiotics surgical

debridement , amputation

Acute rheumatism •Less severe migratory pain•signs of carditis, rheumatic nodules or erythema marginatum

Sickle-cell crisis • Salmonella

Gaucher’s disease •“Pseudo-osteitis’

•enlargement of the spleen and liver.

Management • Supportive treatment for pain and

dehydration.• Splintage (Simple skin traction ,

plaster slab )• Appropriate antimicrobial therapy.• Surgical drainage.

Age Group Types of antibiotics

Neonates up to 6months

• Flucloxacillin + 3rd gen cephalosporin • Flucloxacillin + benzylpenicillin +

gentamycin

Children 6months-6years

• IV flucloxacillin + cefotaxime / cefuroxime

Older child & previously fit adults

• IV flucloxacillin + fusidic acid • For known strep infection :

benzylpenicillin• Allergic to penicillin : 2nd- or 3rd- gen

of cephalosporin like cefotaxime

Elderly & previously unfit patient

• Combination of flucloxacillin + 2nd-/3rd- gen cephalosporin

Condition Types of Antibiotics

Sickle-cell disease patient• Chloramphenicol, • Third-generation

cephalosporin /fluoroquinolone

Heroin Addicts & immunocompromized patient

• Third-generation cephalosporins

• Flouroquinolone (ciprofloxacin)

Patient to be risk at MRSA with acute hematogenous OM

• IV vancomycin + 3rd- gen of cephalosporin

Drainage • When ?

• Clinical features do not improve within 36 hours• Signs of deep pus • Pus is aspirated

• Drained by open operation under general anaesthesia.

• (no obvious abscess) drill into medullary cavity • (extensive intramedullary abscess) cut a small

window in the cortex.• Close wound without drain, • Reapplied traction ,• Encourage movements (crutches)

Complications • Epiphyseal damage and altered bone

growth• Suppurative arthritis• Metastatic infection • Pathological fracture• Chronic osteomyelitis

Referance • Louis Solomon, David Warwick,

Selvadurai, Apley's System of Orthopaedics and Fractures 9th edition

• Maheshwari & Mhaskar ,Essential Orthopedics, 5th edition

• http://www.nejm.org/doi/full/10.1056/NEJMra1213956