1. OSTEOMYELITIS
INFECTIOUS ARTHRITIS
D.Goldberg
WRAMC

2. Osteomyelitis Laboratory Tests Erythrocyte sedimentation rate
White blood cell count
Erythrocyte sedimentation rate
C-reactive protein
Bone aspirate
Blood culture
Antigen Assay

3. Osteomyelitis Etiologic agents by age
Organism Total < >10
S. aureus (50%)
Streptococci (9%)
HIb (4%)
CNS (3%)
Ps. aeruginosa (3%)
S. pneumoniae (2%)
Salmonella (2%)
E. coli

4. Osteomyelitis Specimen site No. done No. Pos Blood 381 138 (36%)
Needle aspirate/surg spec (38%)
Joint fluid (65%)
Wound drainage (70%)
Nelson IDCNA 1995

5. Osteomyelitis BONE MONOSTEAL POLYSTEAL Femur 92 12 Tibia 89 18
Humerus
Fibula
Phalanx
Calcaneos
Radius
Ischium
Metatarsal
Ulna
Ilium
Vertebra

6. Osteomyelitis Neonatal Osteomyelitis Nonspecific signs absent
Indolent process
Nonspecific signs absent
Swelling/tenderness
Multiple sites in 50%
Secondary joint space involvement
S. aureus, group B strep, coliforms

7. Osteomyelitis Sickle Cell Disease GNR’s 6% Staphylococcus 8%
Salmonella 60%
GNR’s 6%
Staphylococcus 8%
Pneumococcus 5%

8. Radiologic Diagnosis X-rays: soft tissue swelling periosteal elevation
focal osteopenia
2 week lag

9. Radiologic Diagnosis Tc scan: accumulation in areas of
inc blood flow and bone
formation
positive in 48 hrs
Three-phase scan
false-neg due to poor
blood flow

10. Radiologic Diagnosis gallium scan: inc uptake in areas
of PMN’s, macrophages
do not show bone well
imaging at 24h and 72h
high sens/high radiation
MRI scan: bone vs soft tissue
T2-inc signal in bone
not for screening

11. Septic Arthritis S.A. Inf Arth Non-IA Volume +/+++ +/+++ +
Color turbid turbid sl turbid
Viscosity reduced reduced normal
WBC’s >
PMN’s >80% >60-80% <50%
Glucose < > >0.80
Bacteria %

12. Distribution of Infected Joints
Septic Arthritis
Distribution of Infected Joints
Knee 30%
Hip Ankle 17
Elbow 11
PIP/MCP 7
Shoulder 2
Nelson PED 1972

13. Septic Arthritis Organism 0-1m 1m-5y >5 (4%) (70%) (26%)
(4%) (70%) (26%)
S. aureus % 11% 33%
Hib % 31% 1%
Streptococci 21% 11% 18%
GNR % % 3%
N. gonnorrhea 7% % 7%
Unknown % 34%

14. Therapy Initial regimes: Neonates nafcillin and cefotaxime
children < cefuroxime
children > nafcillin/cefuroxime
Sickle cell nafcillin and ceftriaxone

15. Therapy: Minimal duration- (clinical response, dec ESR)
Gram negative 4-6 weeks
Staph weeks
H. influenzae 2-4 weeks
N. meningitis 2-4 weeks
streptococci 2-4 weeks
Dagan JPID 1992

16. Contraindications to oral therapy
Inability to swallow
Etiologic agent not established
Inability to perform bacteriocidal levels
No effective oral therapy
Failure of parental abiotics