Distinguishing Osteomyelitis From Ewing Sarcoma on Radiography and MRI.

OBJECTIVE: The purpose of this study was to determine whether clinical and imaging features can distinguish osteomyelitis from Ewing sarcoma (EWS) and to assess the accuracy of percutaneous biopsy versus open biopsy in the diagnosis of these diseases. MATERIALS AND METHODS: Three radiologists reviewed the radiographs and MRI examinations of 32 subjects with osteomyelitis and 31 subjects with EWS to determine the presence of 36 imaging parameters. Information on demographic characteristics, history, physical examination findings, laboratory findings, biopsy type, and biopsy results were recorded. Individual imaging and clinical parameters and combinations of these parameters were tested for correlation with findings from histologic analysis. The diagnostic accuracy of biopsy was also determined. RESULTS: On radiography, the presence of joint or metaphyseal involvement, a wide transition zone, a Codman triangle, a periosteal reaction, or a soft-tissue mass, when tested individually, was more likely to be noted in subjects with EWS (p ≤ 0.05) than in subjects with osteomyelitis. On MRI, permeative cortical involvement and soft-tissue mass were more likely in subjects with EWS (p ≤ 0.02), whereas a serpiginous tract was more likely to be seen in subjects with osteomyelitis (p = 0.04). African Americans were more likely to have osteomyelitis than EWS (p = 0). According to the results of multiple regression analysis, only ethnicity and soft-tissue mass remained statistically significant (p ≤ 0.01). The findings from 100% of open biopsies (18/18) and 58% of percutaneous biopsies (7/12) resulted in the diagnosis of osteomyelitis, whereas the findings from 88% of open biopsies (22/25) and 50% of percutaneous biopsies (3/6) resulted in a diagnosis of EWS. CONCLUSION: Several imaging features are significantly associated with either EWS or osteomyelitis, but many features are associated with both diseases. Other than ethnicity, no clinical feature improved diagnostic accuracy. Compared with percutaneous biopsy, open biopsy provides a higher diagnostic yield but may be inconclusive, especially for cases of EWS. Our findings underscore the need for better methods of diagnosing these disease processes.

A novel device for long bone osteodistraction: description of device and case series.

The purpose of this study was to present a novel intramedullary device (M-Bone; Phenix, Paris, France) that contains a mechanism for internal osteodistraction and bone transport in patients with segmental bone defects or limb length discrepancy after limb salvage operations. A total of five patients with primary bone tumors were enrolled in the study. After implantation, daily lengthening was performed in an outpatient setting either by the patient or with the help of a therapist, without the use of anesthesia. This unique device offers a totally new approach for the treatment of segmental bone defects or limb length discrepancy. It is designed to expand the remaining native bone by a magnetically activated drive system and induces new bone formation using osteodistraction and bone transport.

Relationships among severity of osteonecrosis, pain, range of motion, and functional mobility in children, adolescents, and young adults with acute lymphoblastic leukemia.

BACKGROUND AND PURPOSE: Up to 38% of children receiving treatment for acute lymphoblastic leukemia (ALL) develop osteonecrosis, often without symptoms. Little is known about the association between the degree of osteonecrosis and functional mobility in this population. The purpose of this study was to examine relationships among the degree of osteonecrosis, pain, range of motion (ROM), and functional mobility in people with ALL. SUBJECTS: Thirty-three subjects aged 5 to 27 years with ALL and osteonecrosis participated. METHODS: The extent of osteonecrosis was determined by magnetic resonance imaging (MRI) of the hip and knee according to 2 classification systems, including the Association Research Circulation Osseous (ARCO) and a knee staging scale. Pain, hip and knee ROM, and the Timed Up and Down Stairs (TUDS) Test were used as measures. RESULTS: Correlations were observed between ARCO and hip pain (r=.34), between hip flexion ROM and hip pain (r=-.34), and between knee pain and time on the TUDS Test (r=-.35). DISCUSSION AND CONCLUSION: Physical therapists should consider that people with ALL may have hip or knee osteonecrosis without clinical symptoms. This notion supports the need for MRI in addition to a comprehensive examination of functional mobility.