Osteomyelitis (Adult)

synonyms:

Osteomyelitis ICD-9

• 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 Anatomy

• see Shoulder anatomy, Elbow anatomy, Wrist anatomy, Hip anatomy, Knee anatomy, Ankle anatomy.

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 indicated 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.
• 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
• Cancer
• Benign tumor

Osteomyelitis Complications

• Squamous cell carcinoma (Marjoliin's ulcer)
• Amyloidosis

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.
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