ROENTGENOGRAPHY AS DIAGNOSTIC TECHINIQUE

MORONIKE OLUBUKOLA AJOKEGROUP: 501

FACULTY: IMFDEPARTMENT: RADIOLOGICAL

MEDICINE

Defining Osteomyelitis

What’s in a Name?

Osteomyelitis (Osteo- bone, Myelo- Marrow, and –itis -Inflammation)

Defining Osteomyelitis

What is it?

It is an infection of the of the bone or bone marrow which leads to a subsequent

Inflammatory process.

TYPES OF OSTEOMYELITIS

Acute, subacute and chronicPediatric and adulthoodHematogenous, by direct spread, contigous,

associated with diseaseTraumatic and post traumatic

Acute Osteomyelitis

Types of Acute Osteomyelitis

I. Hematogenous Osteomyelitis

II.Direct Inoculation Osteomyelitis

Acute Osteomyelitis

Hematogenous Osteomyelitis:

Bacterial seeding from the blood.

Seen primarily in Children.

The most common site is the Metaphysis at the growing end of Long Bones in Children, and The Vertebrae and pelvic in Adults.

Acute Osteomyelitis

Direct Inoculation Osteomyelitis

Direct contact of the tissue and bacteria as a result of an Open Fracture or Trauma.

Tend to involve multiple organisms.

Acute Osteomyelitis

Causative Organisms: Staphylococcus aureus (Mainly)

Streptoccous pyogens or pneumoniae. (Less)

H.Influenzae (Young Children)

Salmonella (Sickle-Cell)

Acute Osteomyelitis

Imaging: First 10 days X-Rays Show No Abnormality. By the end of the 2nd Week signs of

rarefaction of Metaphysis and New Bone Formation.

With Healing there is Sclerosis and thickening of Cortex.

MRI may help to distinguish between Bone and Soft-Tissue Infection.

Joint involvement common Septic arthritis X-ray findings Initial radiographs often normal for as long as 7-10 days Localized soft-tissue swelling adjacent to metaphysis

with obliteration of usual fat planes (after 3-10 days) Area of bone destruction (lags 7-14 days behind

pathologic changes) Involucrum = cloak of laminated /spiculated periosteal

reaction (develops after 20 days) Sequestrum = detached necrotic cortical bone (develops

after 30 days) Cloaca formation = space in which dead bone resides

Radiological studiesX-Ray:

First sign is soft-tissue edema at 3-5 days after infection.

Bony changes are not evident for 14-21 days:

1. early radiographic signs of rarefraction (thining of bony tissue sufficient to cause decreased density of bone) of the metaphysis and periosteal new bone formation

2. increasing ragged if treatment is delayed

3. sclerosis and thickening of the bone at healing

Approximately 40-50% focal bone loss is necessary to cause detectable lucency on plain films.

Plain-film radiograph showing osteomyelitis of the second metacarpal (arrow). Periosteal elevation, cortical disruption and medullary involvement are present.

Osteomyelitis of index finger metacarpal head secondary to clenched fist

injury

Osteomyelitis of elbow

Septic arthritis of right hip

The above X-ray of the right ankle of a 10-year-old boy shows lucency in the tibial metaphysis secondary to acute hematogenous osteomyelitis (AHO).

The above X-ray of the left ankle of a 10-year-old boy shows lucency in the tibial metaphysis secondary to acute hematogenous osteomyelitis (AHO).

Here is an X-ray of an AHO lesion extending into the growth plate.

Streptococcal osteomyelitis in a 3-year-old patient presenting with periosteal new-bone formation of the tibia

Subacute Osteomyelitis

Results from a less virulent Microorganism, or a patient with an elevated resistance.

Occurs Mostly at the Distal Femur or Proximal Tibia

On X-Ray we See Brodie’s Abcess:

Small and Oval in shape

It is surrounded by sclerotic bone

May be mistaken for Ostieoid Osteoma

A Brodie abscess is a subacute osteomyelitis with a predilection

for the ends of long bones and the carpus and tarsus. Plain radiographic findings include the following: (1) a central area of radiolucency with a surrounding thick rim of reactive bone sclerosis, which may persist for months; (2) pathognomonic tortuous parallel lucent channels extending toward the growth plate; (3) a variable degree of periosteal new-bone formation; and (4) associated soft-tissue swelling.

Brodie’s abscess, a localised radiolucency usually seen in the metaphyses of long bones. It is sometimes difficult

Treatment of Brodie’s abscess in the metaphysis includes surgical curettage

Subacute Osteomyelitis An image depicting subacute osteomyelitis

Chronic Osteomyelitis

Chronic osteomyelitis is a severe, persistent, and sometimes

incapacitating infection of bone and bone marrow. It is often a recurring condition because it is difficult to treat definitively.

This disease may result from

(1) inadequately treated acute OSM (2) a hematogenous type of osteomyelitis; (3) trauma, (4) iatrogenic causes such as joint replacements and the internal fixation of fractures; (5) compound fractures; (6) infection with organisms, such as Mycobacterium tuberculosis and Treponema species (syphilis); and (7) contiguous spread from soft tissues, as in diabetic ulcers or ulcers in peripheral vascular disease

RadiographyFindingsPlain radiographic findings in acute or sub acute osteomyelitis are deep soft-tissue

swelling, a periosteal reaction, cortical irregularity, and demineralization. The chronic phase of the disease is characterized by thick, irregular, sclerotic bone interspersed with radiolucency, an elevated periosteum, and chronic draining sinuses.

Sclerosing osteomyelitis of Garré most commonly affects the mandible and appears with a focal sclerosing periosteal reaction on radiologic studies.

Chronic recurrent osteomyelitis is benign self-limiting condition that primarily affects long bones in children and adolescents. The metaphysis of long bones are usually affected, and changes may be symmetrical. The appearances are those of confluent areas of bone lysis.

.False Positives/NegativesStress fractures, osteoid osteomas, and other causes of periosteitis may

mimic acute or chronic osteomyelitis.

Osteomyelitis, chronic. Sequestrum of the lower tibia

Osteomyelitis, chronic. Sclerosing osteomyelitis of the lower tibia. Note the bone expansion and marked sclerosis.

Sequelae of Osteomyelitis:Chronic

•Sinus –Intermittent drainage

•Sequestrum –Dead bone

(sclerotic) –Failure to resorb

•Involucrum –New bone envelope •Pathologic fracture

Tuberculous osteomyelitis of sternum

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http://emedicine.medscape.com/article/785020-workup#a0720