Enchondroma

Case contributed by Dr Benedikt Beilstein

Presentation

Long-standing right shoulder pain. Clinical examination revealed classic signs of subcacromial impingement. Shoulder arthroscopy was scheduled and pre-interventional imaging requested.

Patient Data

Age: 50
Gender: Female
CT

No fracture. Degenerative changes in the acromioclavicular joint and subchondral cystic lesions at the insertion of the supraspinatus (SSP) tendon.

Ill-defined lucency at the humeral head-neck junction is noted with pleomorphic calcification within the lesion

MRI

T1 hypointense, PD hyperintense lesion at the humeral head-neck junction (at the site of the former growth plate) measuring approximately 2 x 2 x 3 cm with a relatively narrow zone of transition and some intrinsic signal drop-out (due to calcifications, see CT for correlation). The lesion demonstrates vivid peripheral enhancement after IV contrast administration. Some central enhancement is noted due to translesional septae.

There is moderate tendinopathy of the supraspinatus tendon with thickening of the tendon and focal enhancement in keeping with chronic inflammation. Besides, a small bursal partial tear is noted with fluid in the lateral bursa. There is fluid along the long biceps tendon without interruption of the tendon itself.

The AC joint is thickened and demonstrates moderate enhancement. The subacromial space is narrowed. The other rotator cuff tendons are intact with some fluid along the subscapularis tendon. Mild to moderate subdeltoid and subacromial bursitis.

No fracture. Muscle bellys with normal volume. Type II acromion.

---

CONCLUSION: Subacromial impingement with bursitis and partial tear of the SSP tendon on the background of a chronic tendinopathy.

Incidental finding: Ovoid lesion at the head-neck junction of the proximal humerus with predominantly peripheral enhancement and a narrow zone of transition, in keeping with an enchondroma.

Case Discussion

Classic case of an incidental finding.

The patient came to the hospital with chronic shoulder pain and imaging revealed - apart from the classic subacromial impingement which caused her discomfort - an enchondroma.

Since there was some dispute about the benignity of the lesion and possible instability the lesion was excised. Histology confirmed a benign enchondroma with no features of malignant transformation.

PlayAdd to Share

Case information

rID: 58813
Published: 26th Mar 2018
Last edited: 26th Mar 2018
Inclusion in quiz mode: Included

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.