History 65 year old man with increasing right elbow pain.
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Sagittal proton density MRI through the right elbow on 4/07.
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Coronal Inversion Recovery images of MRI of 4/07.
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Axial proton density and fat suppressed post gadolinium images (same section) MRI of 4/07.
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Findings Radiographs demonstrate an increasing soft tissue olecranon prominence with ongoing destruction of the subjacent bony olecranon. Additionally, enthesophyte at the triceps insertion has been avulsed. MR images demonstrate a thick, rim enhancing fluid collection with adjacent high signal of the soft tissue. The marrow of the olecranon demonstrates a marrow edema pattern and there has been a high grade disruption of the triceps tendon insertion.
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Sagittal proton density MRI through the right elbow on 4/07.
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Coronal Inversion Recovery images of MRI of 4/07.
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Axial proton density and fat suppressed post gadolinium images (same section) MRI of 4/07.
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Diagnosis - Infectious Bursitis/Osteomyelitis Comments: A true bursa such as the olecranon bursa is a synovial lined sac that can become inflammed from infectious and non infectious entities. In either situation, the underlying bone is susceptible to the same aggressive process. MRI is highly suggestive for infection when a marrow edema pattern is present in a diffuse pattern with adjacent soft tissue edema. Thick, enhancing soft tissue or bony lesions in the setting of possible infection are essentially diagnostic. The triceps destruction with avulsion is just a “collateral” injury.
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Resources • Resnick, D. Kransdorf, M. Bone and Joint Imaging. 3rd Edition. 2005. • Karchevsky, M. MRI Findings of Septic Arthritis and Associated Osteomyelitis in Adults. AJR. Jan. 2004. 182: 119-122. •
www.emedicine.com/emerg/topic349.htm
Further Reading • Bursitis and Tendinitis - Chapter from the HSS Manual of Rheumatology and Outpatient Orthopedic Disorders on HSS.edu Sign up for our monthly eNewsletter to find out when a new case will be posted.
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