Radiology case 458-821 Clinical presentation: Eccentric old man with high stepping gait and painless swelling of his knee. There is deformity of the bone ends with marked osteosclerosis and bone loss. Fragmentation and extension of the articular surfaces indicates subluxation and continued movement. There is no regional osteoporosis. The hollowing of the distal femur by the tibia is consistent with subluxation and the short collateral ligaments.

disorder of ossification/development of midline bones autosomal dominant, 33% sporadic skull cranial dysplasia Wormian bones basilar invagination clavicles aplasia / hypoplasia, usually lateral portion other skeletal abnormalities small, high scapula wide symphysis pubis acro-osteolysis

Radiology case 336-2116

Collection of Radiology Teaching cases with radiology images and mock exams

Enchondromas are benign cartilaginous neoplasms that originate in the medullary canal of tubular bones, believed to result from growth of residual benign cartilage rests displaced from the physis. They are often incidental findings, occurring in just under 2% of the population based on autopsy series. Approximately half of all enchondromas occur in the tubular bones of the hands and feet, with others are found in the metaphyses of other long bones. They rarely occur in the pelvis, shoulder girdle, and axial skeleton. Diagnostic Radiology/Musculoskeletal Imaging/Tumors Basic/Enchondroma From Wikibooks, the open-content textbooks collection

eosinophilic granuloma

Illustrated Lecture

Ewing's sarcoma is a malignant tumor that belongs to a broader family of tumors that includes PNET (primitive neuroectodermal tumors). In simple terms, these tumors are all pathologically characterized by the so-called "small round blue cells." Ewing's sarcoma almost always occurs in bone, although other members of the PNET family can occur anywhere. Ewing's is pathologically differentiated from other members of the family on the basis of immunohistochemical staining. Ewing's sarcoma was described by James Ewing in 1920. Similar tumors were reported earlier than this, but it was the work of Ewing which established that the disease was separate from lymphoma or neuroblastoma. Diagnostic Radiology/Musculoskeletal Imaging/Tumors Basic/Ewing sarcoma From Wikibooks, the open-content textbooks collection

Illustrated Lecture

Freiberg infraction

Radiology Site. Case Description

Radiology case 331-3141

hemangioma of vertebrae

Definition Most common of osteochondrodysplasias characterized by formation of multiple osteochondromas. Diagnostic Radiology/Musculoskeletal Imaging/Tumors Basic/Hereditary Multiple Exostoses From Wikibooks, the open-content textbooks collection

hyperostosis frontalis interna