Presentation
Vague history of trauma to left shoulder about 6 weeks back. Complaining of increasing swelling in left scapular region with restricted active shoulder movements. No fever.
Patient Data
There is periosteal reaction from scapular body - sunburst type. There is no fracture.
There is soft tissue thickening abutting supra and infraspinatus fossa of the scapula. It elevates supraspinatus and infraspinatus muscle bellies. There are echogenic lines like rays from the underlying scapular cortex. Cortex is grossly irregular. There is true flow in soft tissue thickening. Teres minor muscle belly abutts scapular cortex and underlying cortex is normal.
Rotator cuff tendons are intact and normal. There is no subdeltoid - subacromial bursal effusion. There is no gleno-humeral joint effusion. There is no collection in the scapular region.
Case Discussion
Adolescent male presented with scapular region swelling for the last few weeks. Radiograph, as well as ultrasound, shows an aggressive type of periosteal reaction involving scapula - sunburst type. It is seen with primary malignant bone tumors like osteosarcoma or Ewing's sarcoma and in osteoblastic metastasis.
Considering the patient's age, a primary bone tumor is more likely the etiology. However, there is no follow up available.