II. Definitions

  1. Osteomyelitis
    1. Inflammation of bone due to infection

III. Classification: Waldvogel System

  1. Acute Osteomyelitis: Hematogenous Seeding
    1. Child with long bone metaphysis infection
    2. Elderly or Immunocompromised with Bone Infection
  2. Chronic Osteomyelitis: Wound associated (surgery, Trauma)
    1. Adult with open injury to bone and soft tissue
  3. Contiguous spread of infection
    1. No generalized vascular disease
    2. Generalized vascular disease

IV. Types

  1. Acute Osteomyelitis (hematogenous spread)
    1. Typical case is a 1-2 week history of fever, Joint Pain in the long bone of a child
    2. Inflammatory bone changes on presentation
  2. Chronic Osteomyelitis (contiguous spread)
    1. Typical case is a 4-6 week history of malaise, regional pain at an open wound in an adult
    2. Necrotic bone changes on presentation

VI. Symptoms

  1. Progressive, localized musculoskeletal pain
    1. Associated erythema and edema of overlying skin
  2. Constitutional, systemic symptoms
    1. May be absent in adults (esp. Immunocompromised, Chronic Osteomyelitis)
    2. Fever (esp. Acute Osteomyelitis)
    3. Malaise
    4. Lethargy or listlessness
    5. Irritability (young children)

VII. Signs

  1. Localized erythema
  2. Soft tissue infection (e.g. Cellulitis)
  3. Bony tenderness
  4. Joint effusion
  5. Decreased range of motion
  6. Exposed bone
  7. Probe To Bone Test (esp. Diabetic Foot Osteomyelitis)

VIII. Differential Diagnosis

  1. Cellulitis or other soft tissue infection
  2. Charcot Foot
  3. Peripheral Arterial Disease Related Chronic Skin Wound
  4. Gout
  5. Fracture
  6. Malignancy
  7. Osteonecrosis
  8. Bursitis
  9. Sickle Cell Vasoocclusive Pain Crisis
  10. SAPHO Syndrome (Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis)

IX. Causes

X. Labs

  1. Inflammation markers
    1. General
      1. More useful in children, especially in ruling out Osteomyelitis (serial negative markers)
      2. Higher Test Sensitivity, but low Test Specificity
    2. Complete Blood Count (CBC)
      1. Leukocytosis
      2. Thrombocytosis
    3. Erythrocyte Sedimentation Rate (ESR) exceeds 70
      1. Test Sensitivity: 28%
    4. C-Reactive Protein (CRP) >8 mg/dl
  2. Bone Biopsy and Culture (Gold Standard)
    1. Test Sensitivity: 95%
    2. Specificity: 99%
    3. Polymicrobial infections are more common in Chronic Osteomyelitis
    4. Consider specific testing in atypical cases (e.g. Mycobacterium tuberculosis)
    5. Organism specific PCR testing
      1. Consider for rapid diagnosis or for culture while on antibiotics
    6. Variable effect on treatment
      1. Mikus (2013) J Vasc Interv Radiol 24(4): S31-2 [PubMed]
  3. Blood Culture
    1. Test Sensitivity: <50%
    2. Positive Blood Culture with clinical findings suggestive of Osteomyelitis may obviate the need for bone culture
  4. Superficial wound culture
    1. Not recommended due to contamination

XI. Imaging

  1. Approach
    1. XRay is typically performed initially as first study given in low cost, readily available
    2. MRI is preferred as a definitive study with best efficacy
    3. Alternatives when MRI contraindicated (risk of False Positives)
      1. Bone Scan with Tagged Leukocyte Scan or SPECT Scan
      2. CT
      3. PET/CT
      4. SPECT Scan
      5. Sulfur Colloid Marrow Scan
    4. Differential Diagnosis of Abnormal Imaging Findings (False Positive causes)
      1. Recent surgery or Trauma related findings
      2. Healed Osteomyelitis
      3. Arthritis
      4. Bone Neoplasm
      5. Paget Disease of Bone
      6. Peripheral Vascular Disease related poor uptake or tissue necrosis
  2. Osteomyelitis XRay
    1. First line study due to low cost and high availability
    2. Narrows differential diagnosis by ruling out other causes
    3. Typically normal in first 2-3 weeks (esp. acute Osteomyelitis in Children)
      1. Earliest findings may include soft tissue swelling, periosteal reaction
    4. Typical appearance is the "rat bite" (lytic lesions) of destroyed bony cortex
      1. Lytic changes not visualized until 50-75% of bone matrix is destroyed
  3. Osteomyelitis Bone Scan
    1. Low Test Specificity (can not distinguish Osteomyelitis from Trauma or recent post-surgical changes)
    2. Distinguishes Cellulitis from Osteomyelitis
    3. In combination with Leukocyte Scintigraphy, efficacy approaches that of MRI
      1. Consider in patients for whom MRI is contraindicated (e.g. due to Pacemaker)
  4. Osteomyelitis MRI
    1. Best Test Sensitivity and Specificity (except in region of surgical hardware)
    2. Perform with IV Contrast
    3. Best distinguishes soft tissue infection from Bone Infection and defines infection margins
  5. Osteomyelitis PET
    1. Very high Test Sensitivity and Test Specificity, but cost prohibitive
  6. Osteomyelitis CT
    1. Avoid for Osteomyelitis evaluation unless MRI contraindicated
    2. May also identify Soft Tissue Abscess, gas formation, foreign bodies and bony destruction
  7. Bone Ultrasound
    1. May have niche applicability (e.g. Sickle Cell Disease related Osteomyelitis)
    2. May diagnosis soft tissue findings (Soft Tissue Abscess, Periostitis)
    3. Used for Ultrasound-guided needle aspiration

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Related Studies

Ontology: Osteomyelitis (C0029443)

Definition (NCI) An acute or chronic inflammation of the bone and its structures due to infection with pyogenic bacteria.
Definition (NCI_NCI-GLOSS) Inflammation of the bone caused by an infection, which may spread to the bone marrow and tissues near the bone. Osteomyelitis can cause severe pain in the infected bone. If it is not treated, it can kill bone tissue.
Definition (CSP) inflammation of the bone marrow and adjacent bone caused by a pyogenic organism; it may remain localized or may spread through the bone to involve the marrow, cortex, cancellous tissue, and periosteum.
Concepts Disease or Syndrome (T047)
MSH D010019
ICD9 730.20, 730.2
ICD10 M86 , M86.9, M86.99
SnomedCT 203244005, 156801003, 203207005, 240141009, 268020008, 156810006, 203206001, 60168000
LNC LP128775-6, MTHU040697
English Osteomyelitides, Unspecified osteomyelitis, OSTEOMYELITIS, Unsp.osteomyelitis-site unspec, Unspecified osteomyelitis of unspecified site, Unspecified osteomyelitis, site unspecified, Osteomyelitis, unspecified, Unspecified osteomyelitis NOS, osteomyelitis (diagnosis), osteomyelitis, Osteomyelitis NOS, Osteomyelitis NOS-unspec, Osteomyelitis [Disease/Finding], bones infections, bone infection, a bacterial infection of the bone or bone marrow, bone infections, unspecified osteomyelitis, bones infection, Osteomyelitis, Unspecified osteomyelitis (disorder), Unspecified osteomyelitis NOS (disorder), Unspecified osteomyelitis of unspecified site (disorder), OM - Osteomyelitis, OSTM - Osteomyelitis, Osteomyelitis (disorder), Pyogenic inflammation of bone, Osteomyelitis, NOS, Pyogenic inflammation of bone, NOS, Osteomyelitis [Ambiguous]
French OSTEOMYELITE, Ostéomyélite SAI, Ostéomyélite non précisée, site non précisé, Ostéomyélite non précisée, Ostéomyélite
Portuguese OSTEOMIELITE, Osteomielite NE, Osteomielite NE de localização NE, Osteomielite
Spanish OSTEOMIELITIS, Osteomielitis NEOM, Osteomielitis no especificada, Osteomielitis no especificada, localización no especificada, osteomielitis no especificada, SAI (trastorno), osteomielitis no especificada, SAI, Unspecified osteomyelitis NOS, osteomielitis no especificada, de sitio no especificado (trastorno), osteomielitis, no especificada (trastorno), osteomielitis no especificada, de sitio no especificado, osteomielitis, no especificada, inflamación piógena del hueso, osteomielitis (trastorno), osteomielitis, Osteomielitis
German OSTEOMYELITIS, unspezifische Osteomyelitis, Stelle unspezifisch, unspezifische Osteomyelitis, Osteomyelitis NNB, Osteomyelitis, nicht naeher bezeichnet, Osteomyelitis, Knochenmarkentzündung
Dutch niet-gespecificeerde osteomyelitis, niet-gespecificeerde osteomyelitis, plaats niet-gespecificeerd, osteomyelitis NAO, Osteomyelitis, niet gespecificeerd, osteomyelitis, Myelitis, Osteo-, Osteomyelitis
Italian Osteomielite non specificata, sede non specificata, Osteomielite NAS, Osteomielite non specificata, Osteomielite
Japanese 骨髄炎, 詳細不明の骨髄炎、部位不明, 骨髄炎NOS, 詳細不明の骨髄炎, コツズイエン, コツズイエンNOS, ショウサイフメイノコツズイエン, ショウサイフメイノコツズイエンブイフメイ
Swedish Osteomyelit
Czech osteomyelitida, Blíže neurčená osteomyelitida, neurčené lokalizace, Osteomyelitida, Osteomyelitida NOS, Blíže neurčená osteomyelitida
Finnish Osteomyeliitti
Korean 골수염, 상세불명의 골수염
Polish Zapalenie kości i szpiku
Hungarian nem meghatározott osteomyelitis, Osteomyelitis, osteomyelitis k.m.n., Nem meghatározott osteomyelitis, hely nem meghatározott
Norwegian Osteomyelitt, Betennelse i bein og beinmarg, Betennelse i ben og benmarg

Ontology: Infection of bone (C2242472)

Definition (MEDLINEPLUS)

Like other parts of the body, bones can get infected. The infections are usually bacterial, but can also be fungal. They may spread to the bone from nearby skin or muscles, or from another part of the body through the bloodstream. People who are at risk for bone infections include those with diabetes, poor circulation, or recent injury to the bone. You may also be at risk if you are having hemodialysis.

Symptoms of bone infections include

  • Pain in the infected area
  • Chills and fever
  • Swelling, warmth, and redness

A blood test or imaging test such as an x-ray can tell if you have a bone infection. Treatment includes antibiotics and often surgery.

Definition (NCI_CTCAE) A disorder characterized by an infectious process involving the bones.
Definition (NCI) An acute or chronic infectious process affecting the bones.
Concepts Disease or Syndrome (T047)
ICD9 730.90, 730.9
ICD10 M86.9
SnomedCT 203325000, 203315005, 203314009, 203206001, 111253001
English Bone infection NOS, of unspecified site, Bone infectn.NOS-site unspecif, Infection in bone, bone infection (diagnosis), bone infection, Bone infec NOS-unsp site, Infection of bone NOS, Infection;bone(s), Infection of bone, Bone Infections, Bone infection NOS (disorder), Bone infection NOS, of unspecified site (disorder), Bone infection, Infection of bone (disorder), bone; infection, infection; bone, Bone Infection, Unspecified infection of bone, Bone infection NOS, Unspecified infection of bone, site unspecified
Spanish infección de hueso, Infección ósea, Infección ósea no especificada, Infección ósea no especificada, localización no especificada, Infección ósea NEOM, infección ósea, SAI, infección ósea, SAI (trastorno), infección ósea, SAI, de sitio no especificado, infección ósea, SAI, de sitio no especificado (trastorno), Bone infection NOS, infección de hueso (trastorno), infección del hueso, infección ósea
Dutch niet-gespecificeerde infectie van bot, plaats niet-gespecificeerd, botinfectie NAO, botinfectie, niet-gespecificeerde infectie van bot, bot; infectie, infectie; bot
French Infection osseuse non précisée, Infection osseuse, Infection osseuse SAI, Infection osseuse non précisée, site non précisé
German Knocheninfektion NNB, Knocheninfektion, unspezifische Knocheninfektion, unspezifische Knocheninfektion, Stelle unspezifisch
Italian Infezione ossea non specificata, sede non specificata, Infezione ossea NAS, Infezione ossea non specificata, Infezione ossea
Portuguese Infecção óssea NE, Infecção óssea NE, localização NE, Infecção óssea
Japanese 詳細不明の骨感染症, 詳細不明の骨感染症、部位不明, 骨感染, ショウサイフメイノコツカンセンショウブイフメイ, ホネカンセン, コツカンセンNOS, コツカンセン, 骨感染NOS, ショウサイフメイノコツカンセンショウ
Czech Kostní infekce NOS, Blíže neurčená kostní infekce, lokalizace neurčena, Blíže neurčená kostní infekce, Kostní infekce
Hungarian Csont fertőzés, Csont fertőzés k.m.n., Csont nem meghatározott fertőzése, Csont nem meghatározott fertőzése, hely nem meghatározott