- 730.__ (Osteomyeliitis, periostitis, and other injections involving bone)
Osteomyelitis Etiology / Epidemiology / Natural History
- Hematogenous: M>F, vertebrae most common site
- Most common organism: S aureus. Pseudomonas aeruginosa in IV drug users.
- Associated with open fractures, diabetics (espcially foot), following musculoskeletal surgery.
- Brodie's Abcess: sclerotic bonesurrounding dense fibours tissue found in chronic osteomyelitis usuallly along the distal tibia.
Osteomyelitis Clinical Evaluation
- Pain, fever, chills, swelling, erythema
Osteomyelitis Xray / Diagnositc Tests
- CBC with differential, ESR (rises within 2 days, continues to rise for 3-5 days even with treatment), CRP (rises witin 6 hours, peaks at 48 hrs, normal witin 1 week), blood cultures, gram stain, CXR. Consider Acid-fast staining, fungal cultures, prolonged incubation times (especially fro infections after arthroscopic surgery).
- Serum IL-6 is indicative of early periprosthetic infection (DiCesare PE, JBJS 2005;87A:1921).
- Xray: demonstrate soft-tissue swelling / loss of tissue planes early. Bone abnormalities require 30-40% bone losss.
- MRI: highest sensitivity and specificity for infection / osteomyelitis. low signal intensity in bone marrow on T1 images may indicate osteomyelits (bone marrow normally has high-signal intensity on T1 images).
- Bone scan: technetium 99m; gallium citrate Ga 67; indium-111 leukocyte-labeled etc.
Osteomyelitis Classification / Treatment
- Stage 1 (Medullary): operative debridment and 4 weeks of antibiotics based on cultures and sensitivities, skeletal stabilization (ex fix), soft tissue coverage (3-7 days after debridement) as indicated.
- Stage 2 (superficial): operative debridment and 2 weeks of antibiotics based on cultures and sensitivities, skeletal stabilization (ex fix), soft tissue coverage (3-7 days after debridement)as indicated.
- Stage 3(Localized): operative debridment and 6 weeks of antibiotics based on cultures and sensitivities, skeletal stabilization (ex fix), soft tissue coverage (3-7 days after debridement) as indicated.
- Stage 4 (Diffuse): operative debridment and 6 weeks of antiobitics based on cultures and sensitivities, skeletal stabilization (ex fix), soft tissue coverage (3-7 days after debridement)as indicated.
- Suppressive treatment with rifampin and a fluoroquilolone or Bactrim for 6 months indicated for patients with contraindications for surgery.
- Surgical Debridement: Resect soft tissuesto supple, well-perfused margins. Resect bone tangentiallyuntil exposed surfaces bleed in a uniform, haversian (cortical)or sinusoidal (cancellous) pattern (paprika sign). All foreign bodies and surgical implants are removed, the woundis lavaged of debris, and the surgical field is prepared forclosure (Sachs BL, CORR 1984;184:256).
- Consider antibiotic beads (vancomycin, tobramycin, gentamycin) especially if lesions with dead space. Beads are typically removed after 4 weeks.
- Consider biodegradeable antibiotic beads (Liu SJ, J Biomed Mater Res 2002;63:807).
- Consider antibiotic impregnated cancellous bone grafts. (Chan YS, J Trauma 2000;48:246).
- Consider Hyperbaric oxygen
- Consider Amputation
- Host Categories: (A)normal, (B)compromised, (C)treatment worse then disease
- Correct any host limitations: smoking, poor nutrition, diabetes control
Osteomyelitis Associated Injuries / Differential Diagnosis
- Healing fracture
- Benign tumor
- Squamous cell carcinoma (Marjoliin's ulcer)
Osteomyelitis Follow-up Care
- Antibiotics generally managed by infectios disease specialitst based on cultures and sensitivities taken during operative debridement.
- Follow responce to treatment with serial ESR and CRP. CRP returns to normal in 1 week, ESR in 3 weeks with adequate treatment.
- Follow-up for wound and ex fix management.
Osteomyelitis Review References
- Calhoun JH, Infect Dis Clin North Am, 2005;19:765.
- Forsbeg, JA, JAAOS, 2011;19:S8-S19