Summary: A 16-year-old female presented to our outpatient clinic with complaints
of pain in the right foot, lower back, right hand, and left knee. She
had a history of recurrent cellulitis of the right foot. The most recent
episode of active osteomyelitis was diagnosed in the right fourth
phalanx by physical exam, magnetic resonance imaging (MRI) and plain
films. She presented to us after finishing her course of antibiotics
with continued pain to evaluate for multifocal osteomyelitis.
Dr. Muzaffar is a Fellow and Dr. Osman is the
Program Director of the Division of Nuclear Medicine, Department of
Radiology, Saint Louis University Hospital, St. Louis, MO.
A 16-year-old female presented to our
outpatient clinic with complaints of pain in the right foot, lower back,
right hand, and left knee. She had a history of recurrent cellulitis of
the right foot. The most recent episode of active osteomyelitis was
diagnosed in the right fourth phalanx by physical exam, magnetic
resonance imaging (MRI) and plain films. She presented to us after
finishing her course of antibiotics with continued pain to evaluate for
the right foot prior to bone scan demonstrated edematous soft tissue of
the dorsal mid- to distal-foot extending to the soft tissue of the
fourth toe (Figure 1). The proximal phalanx of the fourth toe as well as
surrounding edema enhanced post-contrast. Findings were consistent with
osteomyelitis with cellulitis. Plain films demonstrated normal bones,
soft tissues, and joint spaces. A three-phase bone scan demonstrated
hyperemia to the right forefoot with focal uptake on the delayed image
(Figure 2). High-resolution single photon emission computed tomography
and computed tomography (SPECT/CT) was then performed, demonstrating
intense focal uptake in the proximal right fourth toe corresponding to a
nondisplaced fracture in the distal aspect of the right fourth proximal
phalanx (Figure 3).
Osteomyelitis with associated nondisplaced fracture in right proximal phalanx
Osteomyelitis is an infection of the bone
and bone marrow. Pediatric osteomyelitis is generally considered rare.
In the pediatric population, hematogenous route of infection is the most
common route of infection.1 Imaging this infection can be
problematic, particularly in the pediatric population. Multiple imaging
modalities are being used in the workup of children with known or
suspected osteomyelitis. Radiographs are often negative or inconclusive
early in the development of the disease.2 Skeletal
scintigraphy detects physiological changes as low as 5% in bone
turnover, whereas x-ray requires a 30% to 50% loss of bone
mineralization before morphological changes can be detected.2 Furthermore, skeletal scintigraphy is positive as early as the first 24 hours after the onset of symptoms.3
MRI typically has higher sensitivity than CT in detecting osteomyelitis
and has the advantage of defining the extent of infection and
associated soft-tissue changes. However, CT has the advantage of
providing images with high spatial resolution and superb cortical bone
details.4 In addition, MR imaging in pediatrics has
additional limitations, including increased time for imaging and
susceptibility to metal artifacts.5
Chronic recurrent multifocal osteomyelitis is a rare condition that affects multiple bones.6 The
multifocal nature of such a condition requires whole-body imaging.
Skeletal scintigraphy provides a whole-body evaluation with high
sensitivity, but with variable specificity. In addition to the lack of
anatomic localization, there is an inherent limitation to such a
technique. Employing SPECT/CT is better than employing CT or SPECT
alone. The CT component of the SPECT/CT is typically used for lesion
localization and for attenuation correction. The high-resolution image
acquisition feature of the BrightView SPECT/CT provides a unique
opportunity and value to the field of musculoskeletal imaging. It
provides a superb, sub-mm (0.33 mm) evaluation of skeletal anatomy. The
availability of such technology may improve our ability to characterize
lesions and may affect treatment decisions and patient management.
High-resolution SPECT/CT provides the additional information of bone
detail, which may otherwise be unapparent in other imaging modalities.
In this case, a fracture in the fourth toe was identified on SPECT/CT
and not apparent on MRI or plain film. The detection of such fracture
explained the patient’s right foot pain.
- Mader JT, Shirtliff M,
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- Saigal G, Azouz EM, Abdenour G. Imaging of osteomyelitis with special reference to children. Semin Musculoskelet Radiol. 2004;8:255-265.
Maurer AH, Chen DCP, Camargo EE, Wong DF, et al. Utility of three-phase
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- Pineda C, Vargas A, Rodríguez AV. Imaging of osteomyelitis: Current concepts. Infect Dis Clin North Am. 2006;20:789-825.
- Vijayanathan S, Butt S, Gnanasegaran G, Groves AM. Advantages and
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