Age / Sex : 64 / M
Chief complaint: Left shoulder pain (6MA)
Incidentally detected bony abnormality on FU MRI
What is your diagnosis?
Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer).
Courtesy : 최자영 (Ja-Young Choi), 서울대병원(Seoul National University Hospital)
Focal bone abnormality as a complication of ultrasound diathermy
- Interval development of focal bone abnormality 6 months later
- Subchondral arc lesions with low signal intensity in the superolateral humeral head on T1W and high signal intensity on T2W.
- At the side of the bone facing the body surface
- Without involvement of the deeper aspects of the bone marrow
- Disappearance on 3-month FU MRI (not shown)
Differential Diagnosis: Osteonecrosis
- Caused by thermal damage to the bone tissue
- MR features:
- Imaging appearance similar to focal osteonecrosis
- Subchondral rim or arc lesions with low signal intensity on T1W and high signal intensity on T2W.
- Usually smaller and superficially located (different from osteonecrosis)
- Unique location
- Superficial location without involvement of the deeper aspect of the bone marrow.
- On the sides with thinner overlying soft tissue
- On the side of the bone facing the body surface
- Clinical significance
- Usually mild and transient, with apparent full recovery after termination of therapy
- Ultimately heal itself (mostly reversible)
- Yeh LR, Chen CK, Tsai MY, Teng HC, Lin KL. Focal Bone Abnormality as a Complication of Ultrasound Diathermy: A Report of Eight Cases Radiology. 2011;260(1):192-8.
- Kim SJ, Kang Y, Kim DA, Lim JY, Park JH, Oh JH. Focal Bone Marrow Lesions: A Complication of Ultrasound Diathermy Clinics in Shoulder and Elbow 2019;22(1):40-45.