Age / Sex : 62 / M

Chief complaint : right shoulder pain

1) What is your impression?

Two weeks later, you can see the final diagnosis with a brief discussion of this case.

(Quiz는 quiz일 뿐이오니 답안은 한개만 보내주시기 바라오며, 복수의 답안을 보내주시는 분은 정답이 포함되어 있더라도 부득이 semi-correct answer로 처리토록 하겠습니다.)

Courtesy: 최경희(Choi Kyung-Hee) / 이민희(Lee Min Hee), 서울아산병원(Asan medical center)

Calcific tendinitis of pectoralis major with osseous involvement

Discussion

Findings:

An ovoid shaped juxta-cortical calcification in the proximal humerus is seen with minimal periosteal reaction on plain radiograph. Axial and sagittal reformatted CT show calcification with a “comet-tail” appearance in the humeral attachment of pectoralis major tendon with cortical erosion and extension into the cortex. On MR, associated soft tissue and bone marrow edema surrounding hypointense calcification is identified. 

Differential Diagnosis:

Chondrosarcoma or other chondroid matrix producing neoplasm

Other soft tissue or juxtacortical sarcoma

Myositis ossificans

Aavulsion of the pectoralis major tendon

Diagnosis: Calcific tendinitis in pectoralis major tendon with osseous involvement

Discussion:

Calcific tendinitis is a common disorder caused by calcium hydroxyapatite deposition in

a tendon that occurs in as many as 3% of adults.

Cortical erosion and subperiosteal bone formation have been reported in association with calcific tendinitis in a variety of locations, most commonly the insertion of the pectoralis major and tendons of the hip musculature, although osseous involvement is not usual. Hypotheses of bone erosion include active inflammation and local vascularization at the tendon insertion or mechanical effects of muscle traction. It is unknown why some areas appear more predisposed to erosion.

When underlying bone is affected, the characteristic location of involvement in and near the major tendon attachments of the proximal femur and humerus, as well as the lack of a discrete soft tissue mass, are important clues leading to the correct diagnosis of calcific tendinitis.

The comet-tail or flame appearance of the calcification is a characteristic finding on CT. MR offers superior evaluation of bone marrow, but calcification in adjacent tendon may not be identified which leads to need for correlation with radiographic findings.

References:

1.      Flemming DJ, Murphey MD, Shekitka KM, et al. Osseous involvement in calcific tendinitis: a retrospective review of 50 cases. AJR 2003;181:965-972.

2.      Durr H, Lienemann A, Silbernagl H, Nerlich A, Refior H. Acute calcific tendonitis of the pectoralis major insertion associated with cortical bone erosion. Eur Radiol 1997; 7:1215–1217.

3.      John Cahir, Asif Saifuddin. Calcific tendonitis of pectoralis major: CT and MRI findings. Skeletal Radiol 2005; 34:234–238.

4.      Roxanne Chan, David H, Peter J, Barbara N. Calcifying tendinitis of the rotator cuff with cortical bone erosion. Skeletal Radiol 2004; 33:596–599.

5.      Eric J, Georges Y. Atypical calcific tendinitis with cortical erosions. Skeletal Radiol 2000; 29:690–696.