The Hip
Home » Orthopaedics » Hematogenous Osteomyelitis: X-ray manifestations

Hematogenous Osteomyelitis: X-ray manifestations


- See Weiland's Classification

- Discussion:
    - in cases of eventually proven osteomyelitis:
           - < 5% of radiographs are abnormal;
           - < 1/3 of radiographs are positive by one week;
           - by 3-4 weeks about 90% of radiographs are positive;
    - although swelling of soft tissue may be noted on early roentgenograms, bone changes in osteomyelitis are usually not apparent for 8 to 12 days after the onset of clinical symptoms;
    - earliest bone changes are those of destruction or resorption, usually seen as mottled areas of decreased density in metaphyseal area;
    - later, a thin line of newly formed bone parallel to the shaft may be detected in the periosteal regions of the metaphysis;
    - new bone results from infection progressing into the subperiosteal region gradually extends along shaft;
    - if infection is not controlled, the new periosteal bone thickens over succeeding few weeks to become an involucrum;
    - Sequestrum:
            - after several weeks have passed and the disease is in chronic phase, sequestra may appear as opaque areas of bone, usually surrounded by radiolucent zone consisting of exudate and granulation tissue;
    - Brodie's abscess:
           - occasionally, an acute metaphyseal osteomyelitis is contained locally by the host defenses;
           - in such instances, the infection becomes surrounded by scar tissue & rim of reactive bone;
           - resulting cavity or cyst is filled with pus, which may ultimately become sterile;
           - bone abscess resulting from this localized form of the disease is called a Brodie's abscess;
           - reference:
                  - Brodie's abscess. A long-term review.

- MRI:
    - active osteomyelitis displays a decreased signal;

- Diff Dx of Radiolucent Lesions


Subacute osteomyelitis presenting as bone tumors.