Musculoskeletal Key

CLINICAL SUMMARY Chondrosarcoma is the second most common primary bone sarcoma, after osteosarcoma. It has a broad spectrum of presentation largely dependent on the grade of the tumor. Treatment is…

Well-Differentiated, Myxoid/Round Cell, Pleomorphic, and Dedifferentiated Subtypes CLINICAL SUMMARY Liposarcoma is the second most common soft tissue sarcoma after undifferentiated sarcoma, and is further subdivided into several distinctive subtypes. It…

CLINICAL SUMMARY Metastatic carcinoma accounts for the large majority of bone malignancies and, along with multiple myeloma, is the first consideration for any destructive bone lesion in a patient older…

CLINICAL SUMMARY Osteosarcoma is the most common primary bone sarcoma. The peak incidence is in adolescence, but it can also occur as a secondary malignancy in older adults. The rapidly…

CLINICAL SUMMARY Lipoma is the most common soft tissue tumor and consists of benign adipose tissue. It is usually easy to identify on physical examination and on imaging studies. Subcutaneous…

Giant Cell–Containing Tumors Giant Cell Tumor, Chondroblastoma, Nonossifying Fibroma, and Chondromyxoid Fibroma SUMMARY All of these lesions contain giant cells. The distinction is often made by observing the background cells,…

CLINICAL SUMMARY Synovial chondromatosis is a benign synovial disorder resulting in the production of numerous small, intraarticular osteochondral bodies. Treatment, consisting of removal of the bodies and synovectomy, is usually…

Schwannoma (Neurilemmoma) and Neurofibroma CLINICAL SUMMARY Schwannomas and neurofibromas are slow-growing, benign nerve sheath tumors that arise either eccentrically from peripheral myelin-producing cells or centrally from intraneural support cells, respectively….

Malignant Fibrous Histiocytoma, High-Grade Pleomorphic Undifferentiated Sarcoma CLINICAL SUMMARY Undifferentiated sarcoma is the preferred term for the previously named malignant fibrous histiocytoma (MFH). This designation probably encompasses a common endpoint…

Diffuse Pigmented Villonodular Synovitis (PVNS) CLINICAL SUMMARY Diffuse PVNS is a benign, proliferative disorder of the synovium with a distinctive complex nodular appearance on MRI. It is most common in…