Faculty Bibliography

Salmonella osteomyelitis occurs infrequently in children without sickle cell disease. Similarly, acute osteomyelitis of the epiphysis has been rarely reported. We present a case of primary epiphyseal osteomyelitis caused by Salmonella in the distal femur of an otherwise healthy 17-month-old child. Before isolating an organism, parenteral nafcillin provided ineffective clinical, radiographic, and laboratory responses. Repeated fluoroscopic-guided percutaneous surgical drainages allowed for identification of the Salmonella, but did not resolve the epiphyseal infection, as the infection focus was missed. In the effort to eradicate the infection yet minimize further trauma to the epiphysis, computed tomography-guided drainage was performed and the infection subsequently resolved. Owing to its greater localization accuracy and minimal invasiveness, the computed tomography-guided intervention allowed for precise drainage without compromising the contiguous growth plate. At latest follow-up, the patient was ambulating well, had a normal knee examination, and had no evidence of leg length discrepancy or growth disturbance

Bizarre parosteal osteochondromatous proliferation (BPOP), or Nora's lesion, is an unusual surface-based lesion of bone found most commonly in the hands and feet. In the original description of the lesion and in all publications that followed, one of the key imaging characteristics used to define this entity was the lack of cortico-medullary continuity with the underlying bone. The authors present 4 unique cases of pathologically proven BPOP in which cortico-medullary continuity with the underlying bone was demonstrated on imaging. It is believed that florid reactive periostitis, BPOP and turret osteochondroma may reflect points along the same continuum with trauma the likely inciting event. The authors suggest that, given this continuum, it may be possible to have BPOP lesions demonstrating overlapping imaging features with osteochondroma. If this is the case, strict adherence to the standard imaging criterion of lack of continuity between the lesion and the underlying bone may lead to misdiagnosis of these unusual cases of BPOP as osteochondromas

Magnetic resonance imaging (MRI) is increasingly being used to evaluate muscle injuries because of its unparalleled anatomic resolution and high sensitivity in detecting acute and chronic soft-tissue abnormalities. These features allow detection of characteristic injury patterns that lead to accurate diagnoses and grading of severity. The precise assessment of muscle injuries with MRI plays an important role in determining the treatment plan and prognosis of injured athletes. The article begins with a review of the anatomy and MRI characteristics of normal muscle. The general mechanisms of muscle injury and associated MRI findings are discussed, with emphasis on the most common injuries in both the upper and lower extremities. Several mimics of muscle injury are briefly outlined

We describe five primary soft tissue tumors that had histologic features identical to intraosseous aneurysmal bone cyst. The tumors occurred in three females and two males, who ranged in age from 8 to 37 years (median 28 years). They arose in the deep soft tissue of the upper extremities, thigh, and groin region and typically presented as a rapidly growing mass; no involvement of the adjacent bones was identified. The tumors ranged in size from 2.5 to 9 cm (median 4 cm). Grossly, they were surrounded by a thin rim of bone and on sectioning had hemorrhagic cystic spaces delineated by fibrous septa. Histologically, the cystic spaces were filled with blood and the fibrous septa were composed of fibroblasts, osteoclast-type giant cells, and woven bone. Cytogenetic analysis of one tumor showed 46,XY,t(17;17)(p13;q12), a result similar to that which has been reported for intraosseous aneurysmal bone cyst. The differential diagnosis includes a variety of bone-forming and giant cell-containing tumors, the most important being extraskeletal osteosarcoma. Follow-up showed that four patients are free of disease 16 months to 10 years after surgery; one tumor regrew after incomplete initial excision, but the patient has been free of disease 16 months after a second operation. Soft tissue aneurysmal bone cyst is an uncommon benign tumor that can be treated by simple excision, and it should be distinguished from a variety of other reactive and neoplastic processes

Primary neoplasms of the skeleton are rare, but metastatic involvement is, unfortunately, a common occurrence. This is particularly true for certain primary tumors. Skeletal metastases are clinically significant because of associated symptoms, complications such as pathological fracture and their profound significance for staging, treatment and prognosis. Detection of bone metastases is, thus, an important part of treatment planning. The frequency with which metastases are detected varies considerably with the type of primary tumor and with the methodology utilized for detection. Four main modalities are utilized clinically: plain film radiography, CT scan, nuclear imaging and magnetic resonance imaging. In this discussion, we will review literature on the radiology of skeletal metastases with respect to lesion detection, assessment of response to treatment and possible therapeutic implications. The bulk of the discussion will focus on MRI and nuclear studies since most of the recent advances have been made in these areas.

An unusual presentation of mycotic aneurysm is described. In this case, a large thrombosed mycotic aneurysm of the superficial femoral artery was associated with segmental occlusion of the adjacent artery. Small vessels were delineated in the periphery of the aneurysm on angiography.