Shoulder Pain in a 15-Year-Old Boy

Aggressive chondroblastoma of the acromion in a forty-one-year-old patient

“…Periosteal new bone formation and adjacent soft tissue swelling are unusual. 6,7,15 In the present case, tumor dimensions were 65 Â 50 Â 45 mm. There was an evident, gross extension into the adjacent soft tissue with calcification.…”

“…3,6,14 Acromial involvement is unusual, as there are only 2 case reports to date. 7,8,19 There is a slight male predilection and a tendency to appear during the second decade of life. 5,9,10 Pain is nearly always present and is the most common presenting complaint.…”

“…5,9,10 Pain is nearly always present and is the most common presenting complaint. 7,17 Localized swelling, decreased range of motion, and tenderness on palpation are also common clinical characteristics. In our case, pain was the major complaint, with palpable a mass on the dorsum of the scapula.…”

“…Histologically, CB consists of oval mononuclear cells, osteoclast-like multinucleated giant cells, and lacelike deposition of calcified cartilagineous intracellular matrix with chicken wire appearance. 7,11 Microscopic evaluation of the lesion revealed features that were diagnostic for CB.…”

“…6,7,9,18 Although CB is usually nonaggressive and benign, it may show aggressive behavior or malignant transformation and, very infrequently, metastasize. 9,15 It has a predilection for long bones, most commonly the distal femur and proximal tibia.…”