Acute Osteomyelitis

Infection in bone Osteomyelitis l acute (subacute) l chronic l specific (eg TB) l non specific(most common)

Acute haematogenous OM l mostly children l boys> girls l history of trauma

Acute Osteomyelitis Organism l Gram +ve l staphylococus aureus l strep pyogen l strep pneumonie l Gram -ve l haemophilus influnzae (50% < 4 y) l e.coli l pseudomonas auroginosa, l proteus mirabilis

Acute Osteomyelitis Source Of Infection l infected umbilical cord in infants l boils, tonsilitis, skin abrasions l in adults UTI, in dwelling arterial line

Acute Osteomyelitis Source of Infection: zHematogenous zDirect spread zExogenous

Acute Osteomyelitis Pathology l starts at metaphysis l ?trauma l vascular stasis l acute inflammation l suppuration l necrosis l new bone formation l resolution

Acute Osteomyelitis Pathology: zPrimary focus and stage of inflammation zSpread of infection with pus formation zFormation of subperiosteal abscess zPus tracks toward skin to form a sinus zBone infarction (Sequestrum) zNew bone formation (involucrum)

Acute Osteomyelitis

Age variation Neonates: zExtensive bone necrosis zIncreased ability to absorb large sequestrum zIncreased ability to remodel zEpiphysio-metaphyseal vascular connection leading to secondary septic arthritis

Acute Osteomyelitis Clinical Features l severe pain l reluctant to move l fever l malaise l toxemia

Acute Osteomyelitis Clinical Pictures History: Skin lesion Sore throat Trauma

Acute Osteomyelitis Clinical Pictures Symptoms: zPain, restless zMalaise and fever zThe limb is held still (pseudo paralysis) zSometimes mild or absent (neonates)

Acute Osteomyelitis Clinical Pictures Signs: General and Local Laboratory Tests: yCBC yESR+CRP yBlood culture (+ve in 50-70%) yAspiration (Gram stain + culture and sensitivity)

Acute Osteomyelitis Infant l failure to thrive l drowsy l irritable l metaphyseal tenderness l decrease ROM l commonest around the knee

Acute Pyogenic Osteomyelitis Age variation Adults: zNo subperiosteal abscess due to adherent periosteum zSoft tissue abscess zVascular connection with the joint leading to secondary septic arthritis

Acute Osteomyelitis Adult l commonly thoracolumbar spine l fever l backache l history of UTI or urological procedure l old,diabetic,immunocompromised

Acute Osteomyelitis Diagnosis l History and clinical examination l FBC, ESR, B.C. l X-ray (normal in the first (10-14) days l Ultrasound l Bone Scan Tc 99, Gallium 67 l MRI l Aspiration

Acute Osteomyelitis Radiography zPlain X-ray zUltrasound zBone & gallium scan (Sensitive but not specific) zCT scan zMRI

Acute Osteomyelitis

Differential Diagnosis zAcute Septic Arthritis zAcute monoarticular rheumatoid arthritis zSickle cell crisis zCellulitis zEwing’s Sarcoma

Acute Osteomyelitis Treatment Antibiotics: xType? xRoute? xWhen to start? xWhen to stop xMonitoring?

Acute Osteomyelitis Treatment Surgical Drainage: xIndications? xProcedure? xDrilling?

Acute Osteomyelitis Treatment General: zHospitalization zHydration zElectrolyte replacement zAnalgesia zImmobilization

Acute Osteomyelitis Treatment l supportive treatment for pain and dehydration l splintage l antibiotics l surgery

Acute Osteomyelitis Treatment zAntibiotics: Start blindly after taking blood culture. zOlder child & previously fit adults.(staph inf): I/V flucloxacillin and fusidic acid. 2-3 wks. Then orally 3-6 wks. zChild under 4 (haemophilus inf.): Cefuroxime or cefotaxime or co-amoxiclav. zImmunocompromised pts: Third generation cephalosporins.

Acute Osteomyelitis Treatment zNeonates and infants up to 6 months of age :penicillin-resistant Staphylococcus aureus, Group B streptococcus and Gram-negative organisms. flucloxacillin plus a third-generation cephalosporin like cefotaxime. z Children 6 months to 6 years of age :Haemophilus influenzae. combination of intravenous flucloxacillin and cefotaxime or cefuroxime.

Acute Osteomyelitis Treatment zElderly and previously unfit patients, Gram-negative infections, combination of flucloxacillin and a second- or third-generation cephalosporin. zHeroin addicts and immunocompromised patients Unusual infections (e.g. with Pseudomonas aeruginosa, Proteus mirabilis or anaerobic Bacteroides species) third-generation cephalosporins or a fluoroquinolone preparation, depending on the results of sensitivity tests.

Acute Osteomyelitis Treatment zDrainage: 1.CF do not improve within 36 Hrs. 2.Signs of deep pus.( swelling, oedema, fluctuation). 3.If pus is aspirated.

Acute Osteomyelitis Complications l septicemia l metastatic infection l septic arthritis l altered bone growth l chronic osteomyelitis

Acute Osteomyelitis Prognosis Factors affecting prognosis: zOrganisms zInfected Bone zAge of the Patient zTreatment

Subacute Osteomyelitis Clinical features l long history (weeks, months) l pain, limp l swelling occasionally l local tenderness

Subacute Osteomyelitis Pathology Brodies abscess a well defined cavity in cancellous bone

Subacute Osteomyelitis Investigation l X ray l Bone scan l Biopsy(50%) grow organism

Subacute Osteomyelitis Treatment l antibiotics for 6 months l surgery