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Age / Sex : 31 / F
Age / Sex : 31 / F
Chief complaint : Ankle joint pain
1) What is your impression?
Two weeks later, you can see the final diagnosis with a brief discussion of
this case.
* Send Application Answers to In Sook Lee, MD (lis@pusan.ac.kr)
Courtesy :
Yun Sun Choi, MD,
Eulji Hospital, Eulji University
Diagnosis: Osteonecrosis involving the bones about the ankle and foot (multifocal osteonecrosis)
Discussion
Findings:
Ankle radiograph
shows a subchondral lucency to be surrounded by sclerosis in the talar dome. There
is also a subtle sclerosis in the distal portion of the tibia. Sagittal STIR
and T1-weighted SE MR images show ischemic foci in the distal portion of the
tibia, the talus, and the calcaneus characterized by serpentine-like borders. There
is an extensive osteonecrosis of the talar dome with subchondral collapse, and
synovitis of the ankle joint. Note the crescent-like subchondral fracture on coronal
T2-weighted FSE MR image.
Differential Diagnosis: None
Diagnosis: Osteonecrosis involving the bones
about the ankle and foot
Discussion:
Osteonecrosis involving the bones about the ankle and in the foot
is uncommon. Occasionally widespread
osteonecrosis in these sites may be seen, particularly in association with
administration of corticosteroid medications or in patients with systemic
diseases such as systemic lupus erythematosus (SLE), hemoglobinopathies or
diabetes mellitus. In this patient, osteonecrosis relates to lupus. Joint pain in SLE should always evoke
the possibility of osteonecrosis as well as that of synovitis. Typical MR
imaging features are encountered, allowing specific diagnosis.
Osteonecrosis of
the talus may appear as a localized, well-demarcated linear to ovoid area of
subchondral talar dome ischemia with bone marrow edema (BME), or it may have a
more diffuse pattern involving the entire body of the talus, similar in
morphology to bone infarcts seen in other locations. Early in the disease,
there is a small hypointense focus in the superior talar dome. This, however,
is frequently overshadowed by diffuse BME pattern throughout the entire talus.
Caution should be taken not to mistake this pattern of BME for infection,
tumor, or reflex sympathetic dystrophy. It is important to exclude a
subchondral fracture or regional migratory osteoporosis if edema is limited to
the talar head and neck.
Osteonecrosis of
multiple joints may occur during SLE. In patient with a
diagnosis of osteonecrosis and
complaints in other joints, these other areas should be fully evaluated with
plain radiographs and, if inconclusive, with MRI.
References:
1. Resnick D,
Kang HS, Pretterklieber ML. Internal derangements of joints, 2nd ed.
Philadelphia: Saunders, 2007:2228-2230
2. Stoller D.
Magnetic resonance imaging in orthopedics and sports medicine, 3rd
ed. Philadelphia: Lippincott Williams & Wilkins, 2007:1024-1033
3. Guillaume MP,
Brandelet B, Peretz A. Unusual high frequency of multifocal lesions of osteonecrosis in a young patient with
systemic lupus erythematosus. Br J Rheumatol
1998; 37(11):1248-1249
4. LaPorte DM, Mont MA, Mohan V, Jones LC,
Hungerford DS. Multifocal osteonecrosis. J Rheumatol
1998;25(10):1968-1974
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